General Concepts of Food Analysis and Testing PDF

CHAPTER 28 FOOD ANALYSIS Food Analysis is at the heart of safety and quality monitoring. Sampling and analysis of food may be conducted for various purposes, such as surveillance, data collection, monitoring for enforcement, quality control/process monitoring, research, public informati...

CHAPTER 28 FOOD ANALYSIS Food Analysis is at the heart of safety and quality monitoring. Sampling and analysis of food may be conducted for various purposes, such as surveillance, data collection, monitoring for enforcement, quality control/process monitoring, research, public information / survey. Different types of samples are collected and submitted to the laboratory for analysis. Some are sample units from lots or consignments of foods or ingredients. This chapter briefly describes some of the major factors that should be considered when collecting sample units, shipping them to a laboratory, preparing them for analysis, and analysing them. The broad objectives of testing articles of food are Ø Protecting Public Health The most important objective of food testing is to protect public health. Detection of naturally occurring toxins, contaminants, use of unsuitable ingredients, addition of food-additives more than permitted level and failure of declaration of allergic ingredients will all contribute to this objective. Ø Detecting fraudulent activities This is particularly true for imported food where inspection of the manufacturing process establishment is not an option. Ø Providing customers with information to make informed choices Product labelling plays a very important role to help consumers make informed choices about what products to buy. Labelling information ranges from details that may provide guidance on the quality of the food (e.g. Nutritional Facts) to information on the presence or otherwise of substances (e.g allergens, gluten, added sugar) that a consumer may wish to avoid, for ethical or health reasons. Sampling followed by analysis is a vital tool to help check the veracity and accuracy of the labelling information. A Special Book for Food Safety Officer Page 608  Ø Ensuring compliance to the National Food Standards Sampling and analysis is an essential tool to evaluate whether foods meet the compliance to National standards. Enforcement alerts industry that products are being monitored for the purpose of consumer protection and legal compliance. Ø Surveillance and Enforcement Sampling and analysis aid inspection activities either as part of, or associated with, visits to establishments and identify food sector or products where enforcement attention is required. Sampling and analysis are also of use during the investigation of complaints, break outs of food borne illnesses, and follow-up purposes. Ø Providing advice on food safety and quality to Food Business Operator (FBO) Informing food producers or retailers of sampling and analytical results highlight issues that they were not aware of, thus allowing them to take prompt action. Ø Promoting fair trade and deterring bad practice Businesses and consumers alike need to know where they stand. It is, therefore, important that food law is effective and is enforced efficiently and consistently. Fair and effective enforcement helps honest and diligent food businesses and is supported by industry. TYPES OF SAMPLES Broadly there are two types of samples drawn by the Food Safety Officers in our country (a) Legal Sample The enforcement of food law is primarily the responsibility of Food Safety Officials of the State/UTs. To deliver a well- balanced enforcement service and effectively protect consumers, state authorities need to have effective sampling policies, procedures and programmes in place. Effective routine sampling is an essential element in delivering a well-balanced enforcement service and should therefore feature in the enforcement activity of Food Authorities. Legal samples are those samples, where after analysis, if an adverse result is received legal action shall be initiated along with relevant enforcement action for quick relief. In other word these samples can be used for prosecution. Legal samples are drawn as per the sampling procedure detailed in the FSS Act, 2006, rules & Regulations made there under and the entire procedure is to be strictly followed by the Food Safety Officers. (b) Surveillance Sample The samples drawn for purposes of surveillance, survey and research, and cannot be not be used for prosecution. This may be a ongoing process and is normally initiated by the Food Authority. The policy, plan and programme all may be formulated by the Food Authority and is normally forwarded to the State Authorities for drawing samples as per the guidelines enumerated in the plan. The surveillance sampling may also be done by the Central Authorities or jointly by the Central and State Authorities. This type of sampling is done to monitor the safety and quality of food manufactured, sold or imported in the country. A Special Book for Food Safety Officer Page 609 Field Level & Laboratory Sampling Sampling procedure to be followed for collecting sample The persons responsible for drawing the samples should 1. Check all the available information about the commodities/retail packages etc. to be sampled and determine what quantities should be sampled. See also minimum size of samples as listed in the FSS Rules and Regulations, 2011. 2. A representative sample from the lot should be collected Procedure for Representative Sampling Probability sampling deals with the selection of a representative sample from a lot based on chance eliminating human bias. The probability of including any item in the sample is known and the sampling error can be calculated. Probability sampling uses some form of random selection (Figure 10). In a random selection method, the analyst must set up some process or procedure that assures that the different units in the sample population have equal probabilities of being chosen. The following are the most common probability sampling techniques: Simple random sampling In this case, the number of units in the population are known. Each unit is assigned an identification number and a certain number of these identification numbers are selected according to the sample size by using random number tables or computer-generated random numbers. The sample size is determined according to the lot size. The units selected randomly are analysed, and the results are taken as the estimate of the lot. A simple random sample is meant to be an unbiased representation of a group. Example of how to get a simple random sample: put 100 numbered small apples into a basket (this is the population N). Select 10 apples from the basket without looking (this is your sample n). Note that it's important not to look as you could (unknowingly) bias the sample. Simple random sampling is useful when the lot size is small. Since we know the sample size (n) and the lot (N) and it becomes a simple matter of division: n/N x 100 or 10/100 x 100 = 10% This means that every apple in basket has a 10% or 1 in 10 chance of being selected using this method. Systematic sampling: If a systematic pattern is introduced into random sampling, it is referred to as "systematic (random) sampling". For instance, if the pre-packaged foods (Biscuit packet) in a store are arranged in such a way that numbers can be attached ranging from 0001 to 1000. Choose a random starting point, e.g. 25, and then pick every 25th packet thereafter (25, 50, 75, 100……….1000) to give a sample of 40. This method is also used when a complete list of sample units is not available, but when samples are distributed evenly over time or space, such as on a production line. The first unit is selected at random followed by every nth unit after that or at regular time intervals (8h, 16h, 24h………...nth h). Stratified sampling: If the lot is widely dispersed, it may be extremely costly to reach them or perhaps, the lot is not homogeneous and the sub-groups are very different in size. In such a case, precision can be increased through stratified sampling. The segments are based on some predetermined criteria such as geographic location, size or demographic characteristic. Stratified sampling involves dividing the A Special Book for Food Safety Officer Page 610 population (size N) into a certain number of mutually exclusive homogeneous subgroups (size N1, N2, N3, etc.) or strata. Random samples are obtained from each or stratum. This can be used only when subpopulations of similar characteristics can be observed within the whole population. Let us consider a company that produces tomato juice in different plants. If the residual activity of poly galacturonase in tomato juice produced in a particular day is to be evaluated, we can stratify the samples from various batches of each production plant into a subgroup and then select samples from each subgroup for analysis. Cluster sampling: In cluster sampling also, the population is divided into subgroups or clusters followed by randomly selecting only a certain number of clusters for analysis. The main difference between cluster sampling and stratified sampling is that in the latter samples are taken from every single subgroup, while in cluster sampling only randomly selected clusters are sampled. The clusters selected for sampling may be either totally inspected or subsampled for analysis. This sampling method is more efficient and less expensive than simple random sampling, provided clustering is possible. Considering the above said tomato juice example, when using cluster sampling we would group them similar to the previous case, but we would select randomly just a few subgroups for the purpose of study. Composite (Bulk) sampling: This is used to obtain samples from bagged products such as flour, seeds, and larger items in bulk. Small aliquots are taken from different bags, or containers, and combined into a single sample (the composite (Bulk sample) that is used for analysis after mass reduction. Collecting the sample can be at random (Figure 11) or systematic (Figure 12). Composite sampling can also be used when a representative sample of a whole production day in a continuous process is needed. Equal aliquots are taken at different times (random or regular), and then a representative sample is obtained by mixing the individual aliquots. A typical example of composite sampling is a sampling plan for nutritional labelling. A composite of 12 samples with at least six subsamples are taken and analysed for compliance with nutrition labelling regulations. A Special Book for Food Safety Officer Page 611 SAMPLE DIVISION When a number of incremental samples have been taken and a large bulk sample created, a sample divider may be used to reduce the total sample size. For example, 10 kg of bulk sample grain may be reduced to two equal portions of 5 kg. Each 5 kg may be divided to get four samples of 2.5 kg. Which on further dividing provides eight x 1.25 kg samples. Repeated use can further reduce the size of the sample until an appropriate quantity for the final samples is reached. The following sample dividers can be used: § Coning and Quartering rods § Riffle splitter § Centrifugal divider § Boerner Divider Coning and quartering rods: Mix the sample thoroughly on a clean non-absorbent surface. Draw the grain into a conical heap. Flatten the top of the heap and divide into quarters using iron rods. Reject the two diagonally opposite quarters and mix the remaining two (Figure 14). Repeat the complete process until the required laboratory sample is obtained. Riffle Splitter: A riffle splitter (sometimes known as a Jones splitter) is a mechanical device with a series of alternating chutes that deposit one-half of the sample into one discharge bin and the other half into a second bin. The basic components of a riffle splitter include the scoop, an even number of chutes, or riffles, and a pair of collection pans (Figure 15A). The method is limited to free-flowing samples. Riffle splitters utilize multiple fractions (chutes), increasing the number of increments in each round. Riffle splitters can perform well, but the results rely on the skill and training of the operator. The sample needs to be fed into the riffle splitter. Coning and quartering A Special Book for Food Safety Officer Page 612 Centrifugal divider: This is another very useful sample divider, which uses centrifugal force to mix and scatter the material over the dividing surface. In this divider the material flow downwards through a hopper into a shallow disc. When this disc is rotated by an electric motor the material is thrown out by centrifugal force and fall downward. The circle or the area where the material falls is equally divided into two parts by a stationery baffle so that one half fall into one spout and another half in another spout. Boerner Divider: Is an apparatus that divides a composite sample into two equal representative samples with gravity. The Boerner Divider is calibrated to provide accurate splits of + /– 1% on a 1000g sample. The sample is placed in the hopper and then released by moving a valve or slide gate located in the hopper throat. The grain through gravity is evenly dispersed over a cone that has 38 pockets or openings. The grain falling down the sides of the cone is cut into 38 separate streams and all these steams re-joins into two streams and empties into the two pans at the bottom. Since the composite sample passes through 38 different streams to later join into two separate streams, it results into two accurate representative samples that are then collected in two pans for further processing. Devices used to divide and prepare a representative laboratory sample from the bulk sample. Preparing the Laboratory Sample from bulk sample by FSO The sample finally submitted to the laboratory by the FSO is described as the laboratory sample and will take the form of one of the four samples prepared from the Bulk sample. The bulk sample shall be divided to obtain the required number of laboratory samples by use of the apparatus described above. The minimum amount of sample that needs to be collected from the bulk sample for chemical and physical analysis other than microbiological analysis is defined in the FSS Rules and Regulations. The minimum quantity of sample to be sent to the laboratory. The FSO must ensure that he prepares four replicates of the sample for analysis and archiving. FSO divide the sample into four parts and mark and seal or fasten up each part in such a manner as its nature permits and take the signature or thumb impression of the person from whom the sample has been taken in such place and in such manner as may be prescribed by the Central Government. At that A Special Book for Food Safety Officer Page 613 time if person refuses to sign or put his thumb impression, the Food Safety Officer shall call upon one or more witnesses and take his signature or thumb impression, in lieu of the signature or thumb impression of such person. (i) Send one of the parts for analysis to the Food Analyst under intimation to the Designated Officer. (ii) Send two parts to the Designated Officer for keeping these in safe custody. and (iii) Send the remaining part for analysis to an accredited laboratory, if so requested by the food business operator, under intimation to the Designated Officer. If the test reports received under point (i) and (iii) are found to be at variance, then the Designated Officer shall send one part of the sample kept in his custody, to referral laboratory for analysis, whose decision thereon shall be final. When a sample of any article of food or adulterant is taken, the Food Safety Officer shall, by the immediate succeeding working day, send the sample to the Food Analyst for the area concerned for analysis and report. Where the part of the sample sent to the Food Analyst is lost or damaged, the Designated Officer shall, on a requisition made to him, by the Food Analyst or the Food Safety Officer, despatch one of the parts of the sample sent to him, to the Food Analyst for analysis. An article of food or adulterant seized, unless destroyed, shall be produced before the Designated Officer as soon as possible and in any case not later than seven days after the receipt of the report of the Food Analyst: Provided that if an application is made to the Designated Officer in this behalf by the person from whom any article of food has been seized, the Designated Officer shall by order in writing direct the Food Safety Officer to produce such article before him within such time as may be specified in the order. SAMPLING OF IMPORTED FOOD ARTICLES BY AUTHORISED OFFICER Authorised officer at the ports shall conduct visual inspection and take the sample of import food products The Authorised Officer shall draw two parts of food sample of each description or measures (except for aseptic sealed packages); and forward to the food analyst such quantity of sample as specified under the Food Safety and Standards (Laboratory and Sample Analysis) Regulations, 2011. All the requirements of sampling, storage and transportation are the same as described above for the FSO. A Special Book for Food Safety Officer Page 614 TOOLS USED IN SAMPLING All sampling tools must be designed and manufactured so as to serve their intended purpose and preserve the original characteristics of the sampled goods. Sampling tools must meet these general requirements: (a) They must be robust enough to withstand handling operations; (b) They must be easy to clean; (c) All parts must be made of materials resistant to: o the effects of the goods being sampled (e.g. fruit acid or chemicals); o the cleaning agents (e.g. bleach or surfactants); o they must also conform to safety requirements. (d) They must also conform to safety requirements. Sampling devices used for different food products depend on the physical form of the food (e.g liquid, powder, granules, seeds, grains etc.). These include: Sampling liquids: vacuum pumps, dipping vessels, pipette-type samplers, sampling scoops, piston- tube samplers etc. Sampling solids in powder or granulated form: spear samplers, tube-type samplers, zone samplers, sampling trowels, spiral samplers, Sampling frozen goods: hand-drill samplers, etc. Examples of few samplers, Stirrer (Plunger) It is a device used for manual mixing in vessels. It contains a surface sufficient to produce adequate disturbance of the products for mixing liquids and semi-solid products in large as well as small vessels. It is an equipment commonly used to mix the milk or cream to make it uniform in composition throughout the container or can. It is usually made up of stainless steel or aluminum or any metal which will not adversely react with the milk or any other dairy product. It consists of a disc containing several perforations. A long handle is fixed to it at the centre which helps in its to and fro movement in the milk or dairy product. Design of the container should be such that it should not damage the inner surface of the container during mixing. Agitator It is an apparatus used for mechanical agitation of the liquid or semi-solid products. Agitators are mostly provided with a propeller and are introduced into transport, tanks through the inspection port. Paddles agitators consist of usually flat blades attached to a vertical shaft and normally operated at low speed (100-rpm). Dipper This device consists of a small cup fixed to one end of a long handle and is mainly used to collect the sample from the container. The tapered form of the cup permits nesting of the dippers. The capacity of the dipper is usually 50 ml. A Special Book for Food Safety Officer Page 615 Tube Samplers The tube samplers are advantageous in that a representative sample can be obtained regardless of how long the milk has stood before sampling. A column of milk which represents the milk from top to bottom of the container is collected as sample. Piston-tube sampler Syringe-like sampler consisting of a body and a piston. Made from PTFE or polypropylene (PP) with a stainless-steel connecting rod. The piston-tube sampler has three different uses: (i) it can be used like a large syringe to suck in liquids of medium viscosity; (ii) it can be transformed by a slight adjustment into a pipette which is especially suitable for drawing of aggressive liquids or foodstuffs; or (iii) thick or semi-solid materials may be sampled when the end is removed and the sampler is inserted into the material. After withdrawal the contents of the sampler are pushed out into a wide mouth container using the piston. It can be used for liquids, oils, emulsions, pastes. Borers The borers are used for sampling of powdered products. For example, milk powder, flour etc. It should be made entirely of polished stainless steel. The protruding borer edge and point should be sufficiently sharp to serve as a scraper and to facilitate sampling. Sampling Trowel (Sampling scoop/hand scoop): Trowel are made from plastics (PP) or metal (stainless steel), of variable volumes and different handle lengths. Sampling of solids such as grain, free flowing powders and granules. Spiral screw sampler: The sampler consists of a robust spiral body and a handle made from metal (stainless steel). Usual dimensions: lengths from 35 cm, diameter up to 3 cm. The spiral sampler is pressed into the sampled material by pushing and twisting, which ensures the sample is loaded into the spiral. The sampler is then withdrawn and the sample is scraped off by a spatula or scraper into the wide mouth container. Used for paste-like foodstuffs such as peanut butter vegetable or animal fat, jam or honey. Sampler for frozen foods (ice borer) The sampler consists of two parts: a borer and a borer head (sampling cylinder) The sampling cylinder is detachable. The sampler operates on the principle of a screw: the sampler screws into the sample material and simultaneously extracts and conveys the sample into the sampling cylinder. Sampling from frozen and deep-frozen materials and semi-solid substances e.g Deep-frozen goods such as meat or fruit juice concentrates. Hand drill sampler (Conical sampler, tubular sampler), Conical or tubular hand drill with sharp cutting edges and a solid handle, drilling depth 13 cm. Taking samples from soft and semi-solid materials. The sampler into is inserted into the material diagonally taking care drill does not touch the bottom. Then a half turn is made with the drill and pulled out of the sample. The upper approx. 2.5 cm of sampled material is removed. Useful for cheese, butter, cottage cheese paneer, solidified oils etc. A Special Book for Food Safety Officer Page 616 Spear-type sampler: This is a metal or plastic sampler. Made of stainless steel or polypropylene (PP). Usually equipped with a telescopic rod. Used for taking direct samples of bulk goods from sacks, bags or plastic drums, if these goods are in powder or granulated form. The sampler is introduced into the product by piercing the packaging. When the desired zone is reached the sample, chamber is opened using the telescopic handle. As soon as the probe is filled with the sample, the spike of the probe is screwed shut, the spike is withdrawn, and the sample is transferred into a wide mouth container. The hole in the packaging must be closed using tape or a sticker (or a control seal). Also suitable for vertical zone sampling of free-flowing materials such as grain, sugar, flour, semolina, milk powder. Zone sampler: The zone sampler is a metal spear-type sampler with a body having several openings (closed chambers) along its length. The sampler has a robust body made of stainless steel or anodised aluminum. Useful for taking of samples from bulk goods in transport containers, big bags, silos and tanks or goods packed in bags, sacks, barrels or drums. It is suitable for both very fine powders, granules and coarse grains, semolina and nuts. Sampling is possible up to a depth of 2.5 metres. Used for cross-sectional sampling. The zone sampler of appropriate length is introduced into the material at different angles. Samples can be taken from several depths at the same time. In this way, you can check visually whether the product is homogenous throughout its entire volume. Sampling by hand This method is appropriate for all species of grains, legumes, oilseeds etc. Moreover, it is potentially the most suitable method for seed that could get damaged using triers, seeds with wings, seeds with low moisture content. Hands must be washed and the procedure carried out wearing gloves. The open hand is pushed into the container, hand with seeds inside is closed and then hand is withdrawn, taking great care that fingers remain tightly closed around the seeds to prevent escape. Sampling devices used in the bulk sampling of food A Special Book for Food Safety Officer Page 617  Schematic of apparatus for use in sampling of stationary lots in bulk and bags A Special Book for Food Safety Officer Page 618 ACCEPTANCE SAMPLING Acceptance sampling is one of the main areas of statistical quality control and is an inspection procedure. For food safety and quality, acceptance sampling techniques are a commonly used procedure used to determine whether to accept or reject a specific quantity of food lot. Sampling inspection plans are used to assess safety of the food for human consumption and the “fitness for use” of batches of products. The steps involved are, o A random sample is taken from a large quantity of items and tested or measured relative to the quality and / or safety characteristic of interest. o If the sample passes the test, the entire quantity of items is accepted. o If the sample fails the test, either (a) the entire quantity of items is subjected to 100 percent inspection and all defective items repaired or replaced or (b) the entire quantity is returned to the supplier. This provides protection not only to the consumers but also motivates producers to make quality product following good hygienic practices. They may be used for evaluation of attributes or variables or both. Acceptance sampling involves the application of a predetermined plan to decide whether a lot of goods meet defined criteria for acceptance. The risks of accepting “bad” or rejecting “good” lots are stated in conjunction with one or more parameters, for example, quality indices of the plan. Statistical plans can be designed to regulate the probabilities of rejecting good lots or accepting bad lots. They are applicable to Stationary lots and moving as in a production stream. Acceptance sampling is employed in food testing when one or several of the following hold: (i) Testing is destructive. (ii) The cost of 100% inspection is very high. (iii) 100% inspection takes too long The presence of a well-designed plan is important as it provides a consistent model to guide samplers, and serves as a reminder of the important elements of the overall sample analysis program. The precise definition of an acceptance sampling procedure will require the setting or selection of: § The characteristic to be measured § Lot size § An attribute or variables sampling plan § The Limiting Quality (LQ) level for isolated lots; or the AQL (Acceptable Quality Level), for a continuous series of lots § The level of inspection 6. The size of the sample § The criteria for acceptance or rejection of the lot § The procedures to be adopted in cases of dispute A Special Book for Food Safety Officer Page 619 THE CHARACTERISTIC A characteristic is a property, which helps to identify, or differentiate between, items within a given lot. The characteristic may be either quantitative (a specific measured amount) or qualitative (meets or does not meet a specification). Three types of characteristics associated with inspection of food items. Characteristics of food associated with inspection (i) Commodity defects characteristics that may be expressed by two excluding situations as passed/not passed, yes/not, integer/not integer, spoiled/not spoiled (e.g. as applied to visual defects such as loss of colour, mis-grading, extraneous matter, insect infestation etc). Type of Sampling plan - Attribute (ii) Compositional characteristics: characteristics that may be expressed by continuous variables. They may be normally distributed (e.g. most analytically determined compositional characteristics such as moisture content) or they may be non-normally distributed. Type of Sampling plan- Variables with unknown standard deviation' for normally distributed characteristics and 'attributes' for characteristics whose distributions deviate significantly from normal. (iii) Health-related properties (e. g. in the assessment of microbial spoilage, microbial hazards, irregularly occurring chemical contaminants etc). Type of Sampling plan- Quantitative Specified sampling plans to be proposed appropriate to each individual situation (e. g. for microbiological control). LOT SIZE A quantity of a food material delivered at one time and known, or presumed, by the sampling officer to have uniform characteristics such as origin, producer, variety, packer, type of packing, markings, consignor, etc. Where the size or boundary of each lot in a large consignment is not readily established, each one of a series of wagons, lorries, ship's bays, etc., may be considered to be a separate lot. There is no mathematical relationship between sample size (n) and lot size (N). However, to reduce the risk of making an incorrect decision for larger lots. The ratio f = n/N influences the sampling error only when the lot size is small. Moreover, in an objective of consumer protection (in particular health), it is recommended, to choose samples of larger sizes when the lot sizes are large. ATTRIBUTE AND VARIABLE PLANS IN ACCEPTANCE SAMPLING Acceptance sampling is "the middle of the road" approach between no inspection and 100% inspection. There are two major classifications of acceptance plans: by attributes (accept or reject) and by variables. The properties of foods can usually be classified as either attributes or variables. The major sampling plans used in food analysis are: Attribute sampling plan Variable sampling plan A Special Book for Food Safety Officer Page 620 ATTRIBUTE SAMPLING PLAN In attribute sampling plan, sampling is done to decide the acceptability of a lot based on the number of unacceptable items in the sample. The acceptability of an item depends on the presence or absence of a characteristic. In the case of canned fruit, each can that weighs 1 kg or more is accepted, and each unit that weighs less than 1 kg is rejected. If the number of rejected units exceeds a predetermined number, the lot is rejected. If the number of rejected units is less than the predetermined number, the lot is accepted. This plan is based on the binomial or Poisson distribution. There are two types of attribute sampling plan viz., two-class attribute sampling and three-class attribute sampling, which are often used when assessing microbiological contamination of foods. VARIABLE SAMPLING PLAN When actual quantitative information can be measured on sampled items, rather than simply classifying them as acceptable or unacceptable, variables sampling plans can be used. Variable plans are those for which a quality characteristic is measured quantitatively on each item inspected. The average measurement is compared with the standard and used for the acceptability decision. For e.g. salt content, moisture. This type of sampling usually produces data that have a normal distribution such as in the per cent fill of a container and total solids of a food sample. To achieve the same operating characteristic as an attribute plan, a variable sampling plan requires fewer samples than an attribute plan since more information is available in the measurements. When a lot is rejected, the measurements in relation to the specification limits give additional information helps to prevent rejected lots in the future. Such sampling plans have a much greater ability to distinguish between good and bad lots. However, only a single characteristic may be measured with each sampling plan. Also, some characteristics are not measurable on a continuous scale, such as appearance, texture of meat, colour, or odour. This plan is usually based on normal distribution. A Special Book for Food Safety Officer Page 621 BASIC/CLASSICAL METHOD FOR FOOD ANALYSIS Food Testing and analysis is an essential part of the food safety ecosystem to assure that the food is safe to consume. For the same, FSSAI recognizes and notifies NABL accredited food laboratories under Section 43 of Food Safety and Standards Act,2006. FSSAI through its Scientific Panel on Methods of Sampling and Analysis is involved in revision of the existing testing methodologies and new parameters for analysis of various food articles. So far 13 new manuals on methods of food analysis have been finalized including Milk and Milk Products, Oil and Fats, Fruits and Vegetable products, etc. A Methods Review Group has been constituted to review manual of methods and update them, with experts from Scientific/Research Institutions, Regulatory Bodies, Independent Scientific experts (including instrumentation companies, private labs) etc. A method used to detect the certain components of a food mixture and to identify the main class of food. Types of Food Test: 1. Benedict’s Test (for sugar) 2. Biuret Test (for protein) 3. Ethanol Emulsion Test (for fat) 4. Iodine Solution Test (for starch) 1. TEST FOR SUGAR Benedict’s Test Benedict’s test is a chemical test that can be used to check for the presence of reducing sugars in a given analyte. Therefore, simple carbohydrates containing a free ketone or aldehyde functional group can be identified with this test. The test is based on Benedict’s reagent (also known as Benedict’s solution), which is a complex mixture of sodium citrate, sodium carbonate, and the pentahydrate of copper (II) sulfate. When this solution exposed to reducing sugars, the reactions undergone by Benedict’s reagent result in the formation of a brick-red precipitate, which indicates a positive Benedict’s test. An image detailing the changes in the colour of Benedict’s reagent (from clear blue to brick-red) that are triggered by exposure to reducing sugars is provided below. A Special Book for Food Safety Officer Page 622 Benedict’s Test Procedure Preparation of Benedict’s Reagent One litre of Benedict’s reagent can be prepared by mixing 17.3 grams of copper sulfate pentahydrate (CuSO4.5H2O), 100 grams of sodium carbonate (Na2CO3), and 173 grams of sodium citrate in distilled water (required quantity). Here, the copper (II) sulfate acts as a source of Cu2+ ions, the sodium carbonate provides an alkaline medium, and the sodium citrate forms complexes with the Cu2+ ions. Distilled water is used as a solvent. The purity of Benedict’s reagent can be checked by heating it in a test tube. No changes in the blue colour of the solution upon heating is an implication that the reagent is pure. Testing for Reducing Sugars One millilitre of the analyte sample must be mixed with 2 millilitres of Benedict’s reagent and heated in a bath of boiling water for 3 to 5 minutes. The development of a brick-red coloured precipitate of cuprous oxide confirms the presence of reducing sugars in the analyte. Interpreting the Results of Benedict’s Test Colour of the Precipitate g % of Reducing Sugar Green 0.5% Yellow 1% Orange 1.5% Red 2% 2. TEST FOR PROTEIN Biuret Test The biuret test is a chemical test that can be used to check for the presence of peptide bonds in a given analyte. Therefore, the biuret test can be also be used to gauge the amount of protein present in the analyte. In this test, the presence of peptides results in the formation of pale purple coloured (or mauve coloured) coordination compounds of the copper (II) ion (when the solution is sufficiently alkaline). An image detailing a positive biuret test and the characteristic pale purple colour that denotes it is provided below. A Special Book for Food Safety Officer Page 623 It can be noted that several variants of the biuret test have been developed. Notable examples of such variations include the modified Lowry test and the BCA test. It can also be noted that the intensity of the purple colour and, therefore, the absorption at 540 nanometers is directly proportional to the concentration of proteins in the given analyte (as a consequence of the Beer-Lambert law). A positive reaction for this test is also received when the analyte contains biuret molecules ([H2N-CO]2NH) since the bonds in this molecule are similar to peptide bonds. Biuret Test Procedure The procedure that can be followed to conduct a biuret test is provided below. An aqueous solution of the analyte must be prepared by dissolving it in water. A small amount of this aqueous solution must be treated with 1% sodium hydroxide or potassium hydroxide. To this mixture, a few drops of CuSO4 (aq) must be added. If the solution turns purple upon the addition of copper (II) sulfate, the presence of protein in the analyte is confirmed. 3.TEST FOR FATS Emulsion test Emulsion tests can be used to test for the presence of lipids in a sample. In this test, the sample is required to be suspended in ethanol causing lipids (if present) to be dissolved. This is because lipids are soluble in alcohol. Then, this liquid is gradually poured into water. 4.TEST FOR STARCH Iodine Test In simple words, starch can be defined as the most important complex carbohydrate compounds. It is a polysaccharide and glucoside reserve of plants. It is a renewable and biodegradable product, so it can act as a perfect raw material and a substitute for fossil-fuel components in making detergents, glues, plastics, etc. The starch molecules comprise a large number of glucose units that are bound together by glycosidic bonds and are produced by all vegetables and other plant sources through the process of photosynthesis. The starch molecules function as energy storage in plant cells, which is necessary for their growth, development, and reproduction. Barley, potatoes, maize, rice, wheat are a few examples of plant products from which starch are extracted and distributed to different industries. A Special Book for Food Safety Officer Page 624 Materials Required Knife Spatula Porcelain tile. Iodine solution Food sample – Potato or any other vegetables or fruits. Procedure o Take a fresh Potato which is washed, cleaned and dried. o Peel off the skin of the potato. o Cut the potato into small cubes or slices. o With the help of clean and dried Spatula, place the potato samples on the clean and dried porcelain tile. o Add 2 to 3 drops of dilute iodine solution on the potato samples. o Keep the slide undisturbed and observe the changes. Observations There will be a change in colour. A blue-black colour develops on the slice or cubes of the potato samples. Result The result is positive. According to the observation the food sample or the potato slice turned to blue-black on adding the iodine solution. This proves the presence of starch in the given plant source. This was a simple experiment which is used to check for the presence of starch. This Iodine Test for Starch can be performed for both the liquid and solid food samples. A Special Book for Food Safety Officer Page 625  Minimum quantity of Laboratory sample Article of Food / Material Quantity Milk 500 ml Sterilized Milk / UHT Milk 500 ml Malai / Dahi 200 g Yoghurt / Sweetened Dahi 500 g Chhana / Paneer / Khoya / Shrikhand 250 g Cheese / Cheese spread 200 g Evaporated Milk / Condensed Milk 200 g Ice-cream / Softy / Kulfi / Ice candy / Ice lolly 300 g Milk Powder / Skimmed Milk Powder 250 g Infant Food / Weaning Food 500 g Malt Food / Malted Milk Food 300 g Butter / Butter Oil / Ghee / Margarine / Cream / Bakery Shortening 200 g Vanaspati, Edible Oils / Fats 400 g Carbonated Water 3L Baking Powder 100 g Arrow root / Sago 100 g Corn flakes / Macaroni Products / Corn Flour / Custard Powder 200 g Spices, Condiments and Mixed Masala (Whole) 500 g Spices, Condiments and Mixed Masala (Powder) 500 g Nutmeg / Mace 250 g Asafoetida 100 g Compounded Asafoetida 150 g Saffron 20 g Gur / jaggery, Icing Sugar, Honey, Synthetic Syrup, Bura 250 g Cane Sugar / Refined Sugar / Cube Sugar, Dextrose, Misri / Dried Glucose Syrup 200 g Artificial Sweetener 200 g Fruit Juice / Fruit Drink / Fruit Squash 1L Tomato Sauce / Ketch up / Tomato Paste, jam / Jelly / Marmalade / Tomato Pure / 300 g Vegetable Sauce Non-Fruit Jellies 200 g Pickles and Chutneys 200 g Oilseeds / Nuts / Dry Fruits 250 g Tea / Roasted Coffee / Roasted Chicory 500 g Instant Tea / Instant Coffee / Instant Coffee-Chicory Mixture 100 g Sugar Confectionery / Chewing Gum / Bubble Gum 100 g Chocolates 200 g Edible Salt 200 g Iodised Salt / Iron Fortified Salt 200 g Manual for Food Safety Officers (draft for designing) 1 kg Atta / Maida / Suji / Besan / Other Milled Product / Paushtik Fortified Atta / Maida 500 g Biscuits and Rusks 200 g Gelatin 150 gms Bread / Cakes / Pasties 250 gms Catechu 150 g Vinegar / Synthetic Vinegar 300 g Food Colour 25 g Food colour preparation (Solid / Liquid) 25 g/100 mL A Special Book for Food Safety Officer Page 626  Natural Mineral Water / Packaged Drinking Water 4000 ml in three minimum original sealed packs Silver Leaf 2g Prepared Food 500 g Proprietary Food, (Non-Standardised Foods) 500 g Canned Foods 6 sealed cans Food not specified 500 g Food packaging material taken from manufacturer 8 x 1000 x 9 sq.cm. surface area Food packaging material from small consumer packages Complete packaging material used for one container A Special Book for Food Safety Officer Page 627 CHAPTER 29 MODERN ANALYTICAL TECHNIQUES INTRODUCTION The aim of food products analysis is obtaining results, which provides information about the composition of food products or food raw material sample. This obtaining information can be carried out on different levels. These levels can be the following: elemental, molecular, and structural. The level of the chemical elements (elemental) means that answer can be given to the question that what (qualitative analysis) and how much (quantitative analysis) can be found in the given sample. Although, on the molecular level the answer can be given about what compounds and crystalline forms consist of the sample from the building elements. The examination of the structure can mean arrangement of the molecules as well (e.g.: determining the order of the amino acids in a protein). The difficulty of the analytical task differs among levels. Any technique selected for food analysis depends on what the researcher is looking for, and there is a host of food properties from which to choose. The development and application of analytical methods and techniques in food science has grown parallel to the consumers concern about what is in their food and the safety of the food they eat. MODERN ANALYTICAL TECHNIQUES/ INSTRUMENTAL ANALYTICAL METHODS FOR FOOD ANALYSIS At the beginning of the twentieth century scientists began to take more and more advantage of the different opportunities provided by the measured components’ physical correlations. With the help of them they developed better and better instrumental analytical methods which they found solution for several problems of the classical analytical methods. Such physical characteristics are for example: conductivity, electrode potential, light absorption, light emission, fluorescence and the mass-charge ratio, which were started to be used for quantitative analysis. Furthermore, highly effective chromatographic and electrophoretic techniques were also used to substitute distillation, extraction or precipitation, applied to divide the mixture of components of food or food raw material samples with unusually complex matrix before the qualitative or quantitative determination. The aforementioned new methods, used for the separation and determination of different components, are called instrumental analytical methods. The rapid development of the computer and electronics industry highly contributed to the improvement and spread of the modern instrumental analytical methods. characteristics of the analytical methods 1. Selectivity, 2. Specificity, 3. Ruggedness, 4. Measurement range, 5. Linearity, 6. Detection limit, 7. Quantitation limit, A Special Book for Food Safety Officer Page 628  8. Accuracy, and 9. Precision. 1. Atomic absorption spectrometry In atomic absorption spectrometry (AAS) the analysed element is transformed into free ground state atoms with energy transfer (in a flame or graphite furnace). Through this atomic vapour a light with the wavelength characteristic for the element that is directed through and the decrease of the intensity of light is measured. The wavelength of the used light determines the quality of the analysed material, while the relative decrease of the intensity of light determines the relative and absolute quantity of the element. Hollow Cathode Lamp Flame Monochromator Detector Or Polychromator 2. Gas chromatography Gas chromatography is a column chromatography technique, where the mobile phase is gas and the stationary phase is either an immobilized liquid or a solid packed in a closed tube. GC is useful for separation of thermally stable volatile components of a mixture (for example fatty acid methyl esters). During the gas–liquid GC the sample is vaporized and injected into the head of the column. By using a controlled temperature gradient, the sample is transported through the column by the mobile phase, which usually is an inert gas. The volatile components then are separated based on boiling point, molecular size, and polarity. GC has been used for the determination of fatty acids, triglycerides, cholesterol and other sterols, gases, solvent analysis, water, alcohols, and simple sugars, as well as oligosaccharides, amino acids and peptides, vitamins, pesticides, herbicides, food additives, antioxidants, nitrosamines, polychlorinated biphenyls, drugs, flavor compounds, and many more. 3. Supercritical fluid chromatography Supercritical fluid chromatography (SFC) refers to chromatography that is performed above the critical pressure (Pc) and critical temperature (Tc) of the mobile phase. A supercritical fluid (or compressed gas) is neither a liquid nor a typical gas. The combination of Pc and Tc is known as the critical point. A supercritical fluid can be formed from a conventional gas by increasing the pressure or from a conventional liquid by raising the temperature. Carbon dioxide frequently is used as a mobile phase for SFC, because it is not a good solvent for polar and high molecular-weight compounds. Other supercritical fluids are nitrous oxide, trifluoromethane, sulphur hexafluoride, pentane and ammonia. The high diffusivity and low viscosity of supercritical fluids mean decreased analysis times and improved resolution compared to LC. A Special Book for Food Safety Officer Page 629  SFC offers a wide ranges of selectivity adjustment, by changes in pressure and temperature as well as changes in mobile phase composition and the stationary phase. SFC makes possible separation of nonvolatile, thermally labile compounds that are not amenable to GC. SFC can be performed by using either packed columns or capillaries, and has used primarily for nonpolar compounds. Fats, oils, and other lipids are compounds which SFC is increasingly applied. 4. High-performance liquid chromatography Originally, high-performance liquid chromatography (HPLC) was the acronym for high pressure liquid chromatography, reflecting the high operating pressures generated by early columns. By the late 1970s, high performance liquid chromatography had become the preferred term, emphasizing the effective separations achieved. HPLC can be applied to the analysis of any compound with solubility in a liquid that can be used as the mobile phase. Although most frequently employed as an analytical technique, HPLC also may be used in the preparative mode. There are many advantages of HPLC over traditional low-pressure column liquid chromatography, because many analyses can be accomplished in 30 min or less, a wide variety of stationary phases, improved resolution and greater sensitivity, because various detectors can be employed, and easy sample recovery, because of less eluent volume to remove. A basic HPLC system consists of a pump, injector, column, detector, and data system. HPLC is widely used for the analysis of small molecules and ions, such as sugars, vitamins, and amino acids, and is applied to the separation and purification of macromolecules, such as proteins and polysaccharides. 5.Gas Chromatography-Mass Spectromatry (GC-MS) Gas Chromatography–Mass Spectrometry (GC-MS) is a hyphenated analytical technique that combines the separation properties of gas-liquid chromatography with the detection feature of mass spectrometry to identify different substances within a test sample. GC is used to separate the volatile and thermally stable substitutes in a sample whereas GC-MS fragments the analyte to be identified on the basis of its mass. The further addition of mass spectrometer in it leads to GC-MS/MS. Superior performance is achieved by single and triple quadrupole modes. A Special Book for Food Safety Officer Page 630 Foods and beverages have several aromatic compounds existing naturally in native state or formed while processing. GC-MS is exclusively used for the analysis of esters, fatty acids, alcohols, aldehydes, terpenes etc. GCMS is also used to detect and measure contaminants, spoilage and adulteration of food, oil, butter, ghee that could be harmful and should to be controlled and checked as regulated by governmental agencies. It is used in the analysis of piperine, spearmint oil, lavender oil, essential oil, fragrance reference standards, perfumes, chiral compounds in essential oils, fragrances, menthol, allergens, olive oil, lemon oil, peppermint oil, yiang oil, straw berry syrup, butter triglycerides, residual pesticides in food and wine. 6. Infra-red (IR) spectroscopy Infra-red spectroscopy is used to measure IR radiation absorbed by or reflected from a sample. The absorption of IR radiation is related to the changes of vibrational or rotational energy states of molecules. Its applications for analysis of gaseous, liquid or solid samples, identification of compounds and their quantitative analysis etc. The IR spectrum obtained for functional groups of molecules, constitution of molecules and interaction among molecules provides information about the samples. Main components of an instrument, 1. radiation source 2. measuring (and reference) cell 3. wavelength selector 4. detector (transducer) A Special Book for Food Safety Officer Page 631 MASS SPECTROMETRY In the food industry, food safety and quality are still performed as an important issue all over the world, which are directly related to people’s health and social progress. Consumers are gradually looking for quality seals and trust marks on food products, and expect manufacturers and retailers to provide products of high quality. All of these factors have underlined the need for reliable techniques to evaluate the food quality (Haiyan and Yong, 2007). Protein, Fiber and fat content are the routine biochemical food quality parameters which are employed world-wide to determine the quality of any food matrices. Mass spectrometry (MS) is an extremely valuable analytical technique in which the molecules in a test sample are converted to gaseous ions that are subsequently separated in a mass spectrometer according to their mass-to-charge (m/z) ratio and detected. The mass spectrum is a plot of the (relative) abundance of the ions at each m/z ratio. Note that it is the mass to charge ratios of ions (m/z) and not the actual mass that is measured. If for example, a biomolecule is ionised by the addition of one or more protons (H+ ions) the instrument measures the m/z after addition of 1 Da for each proton if the instrument is measuring positive ions or m/z minus 1 Da for each proton lost if measuring negative ions. The development of two ionisation techniques, electrospray (ESI) and matrix-assisted laser desorption/ionisation (MALDI), has enabled the accurate mass determination of high-molecular-mass compounds as well as low-molecular-mass molecules and has revolutionised the applicability of mass spectrometry to almost any biological molecule. Applications include the new science of proteomics as well as in drug discovery. The latter includes combinatorial chemistry where a large number of similar molecules (combinatorial libraries) are produced and analysed to find the most effective compounds from a group of related organic chemicals. Mr is sometimes used to designate relative molar mass. Molecular weight (which is a force not a mass) is also frequently and incorrectly used. Mr is a relative measure and has no units. However, Mr is numerically equivalent to the mass, M, which does have units and the Dalton is frequently used. The essential features of all mass spectrometers are therefore 1. production of ions in the gas phase; 2. acceleration of the ions to a specific velocity in an electric field; 3. separation of the ions in a mass analyser; and 4. detection of each species of a particular m/z ratio. The instruments are calibrated with standard compounds of accurately known Mr values. In mass spectrometry the carbon scale is used with 12C ¼ 12.000000. This level of accuracy is achievable in high-resolution magnetic sector double-focussing, accelerator mass spectrometers and Fourier transform mass spectrometers. The mass analyser may separate ions either by use of a magnetic or an electrical field. Alternatively, the time taken for ions of different masses to travel a given distance in space is measured accurately in the time-of-flight (TOF) mass spectrometer (Section 9.3.8). Any material that can be ionised and whose ions can exist in the gas phase can be investigated by MS, remembering that very low pressures, A Special Book for Food Safety Officer Page 632 i. e. high vacuum, in the region of 106 Torr are required (Torr is measure of pressure which equals 1 mm of mercury (133.3 Pa; atmospheric pressure is 760 Torr)). The majority of biological MS investigations on proteins, oligosaccharides and nucleic acids is carried out with quadrupole, quadrupole–ion trap and TOF mass spectrometers. In the organic chemistry/biochemistry area of analysis, the well-established magnetic sector mass spectrometers still find wide application and their main principles will also be described. The treatment of mass spectrometry in this chapter will be strictly non-mathematical and non-technical. However, the intention is to give an overview of the types of instrumentation that will be employed, the main uses of each, complementary techniques and advantages/disadvantages of the different instruments and particular applications most suited to each type. Data analysis and sample preparation to obtain the best sensitivity for a particular type of compound will also be covered. Components of a mass spectrometer 1. A high vacuum system (106 torr or 1 m torr): These include turbomolecular pumps, diffusion pumps and rotary vane pumps. 2. A sample inlet: This comprises a sample or target plate; a high-performance liquid chromatography (HPLC), gas chromatography (GC) or capillary electrophoresis system; solids probe; electron impact or direct chemical ionisation chamber. 3. An ion source (to convert molecules into gas-phase ions): This can be MALDI; ESI; fast atom bombardment (FAB); electron impact or direct chemical ionisation. 4. A mass filter/analyser: This can be: TOF; quadrupole; ion trap; magnetic sector or ion cyclotron Fourier transform (the last is also actually a detector). 5. A detector: This can be a conversion dynode, electron multiplier, microchannel plate or array detector. High vacuum system Ion Mass Data Inlet Detector source filter system A Special Book for Food Safety Officer Page 633 MASS SPECTROMETER Mass spectrometer is an analytical tool that is used to measure the mass-to-charge ratio of ions. The results are presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures. A mass spectrum is a plot of the ion signal as a function of the mass-to-charge ratio. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. In order to measure the characteristics of individual molecules, a mass spectrometer converts them to ions so that they can be moved about and manipulated by external electric and magnetic fields. The three essential functions of a mass spectrometer, and the associated components, are: Ø A small sample is ionized, usually to cations by loss of an electron. (The Ion Source) Ø The ions are sorted and separated according to their mass and charge. (The Mass Analyzer) Ø The separated ions are then measured, and the results displayed on a chart. (The Detector) Because ions are very reactive and short-lived, their formation and manipulation must be conducted in a vacuum. Atmospheric pressure is around 760 torr (mm of mercury). The pressure under which ions may be handled is roughly 10-5 to 10-8 torr (less than a billionth of an atmosphere). Each of the three tasks listed above may be accomplished in different ways. In one common procedure, ionization is effected by a high energy beam of electrons, and ion separation is achieved by accelerating and focusing the ions in a beam, which is then bent by an external magnetic field. The ions are then detected electronically and the resulting information is stored and analyzed in a computer. A mass spectrometer operating in this fashion is outlined in the following diagram. The heart of the spectrometer is the ion source. Here molecules of the sample (black dots) are bombarded by electrons (light blue lines) issuing from a heated filament. This is called an EI (electron-impact) source. Gases and volatile liquid samples are allowed to leak into the ion source from a reservoir (as shown). Non- volatile solids and liquids may be introduced directly. Cations formed by the electron bombardment (red dots) are pushed away by a charged repeller plate (anions are attracted to it), and accelerated toward other electrodes, having slits through which the ions pass as a beam. Some of these ions fragment into smaller cations and neutral fragments. A perpendicular magnetic field deflects the ion beam in an arc whose radius is proportional to the mass of each ion. Lighter ions are deflected more than heavier ions. By varying the strength of the magnetic field, ions of different mass can be focused progressively on a detector fixed at the end of a curved tube (also under a high vacuum). A Special Book for Food Safety Officer Page 634 When a high energy electron collides with a molecule it often ionizes it by knocking away one of the molecular electrons (either bonding or non-bonding). This leaves behind a molecular ion (colored red in the following diagram). Residual energy from the collision may cause the molecular ion to fragment into neutral pieces (colored green) and smaller fragment ions (colored pink and orange). The molecular ion is a radical cation, but the fragment ions may either be radical cations (pink) or carbocations (orange), depending on the nature of the neutral fragment. Various types of Mass Spectrometry 1. AMS (Accelerator Mass Spectrometry) 2. Gas Chromatography-MS 3. Liquid Chromatography-MS 4. ICP-MS (Inductively Coupled Plasma-Mass spectrometry) 5. IRMS (Isotope Ratio Mass Spectrometry) 6. Ion Mobility Spectrometry-MS 7. MALDI-TOF 8. SELDI-TOF 9. Tandem MS 10. TIMS (Thermal Ionization-Mass Spectrometry) 11. SSMS (Spark Source Mass Spectrometry) 12. Rarely used Mass Spectrometry Ionization Types A Special Book for Food Safety Officer Page 635 CHAPTER 30 QUALITY ASSURANCE & QUALITY CONTROL Quality Quality can be defined as a measure of purity, strength, flavor, color, size, workmanship, and condition, and or any other distinctive attribute or characteristic of the product. Countries where food is abundant, people choose foods based on a number of factors which can in sum be thought of as "quality." Quality has been defined as degree of excellence and includes such things as taste, appearance, and nutritional content. We might also say that quality is the composite of characteristics that have significance and make for acceptability. Acceptability, however, can be highly subjective. Quality and price need not go together, but food manufacturers know that they generally can get a higher price for or can sell a larger quantity of products with superior quality. often "value" is thought of as a composite of cost and quality. More expensive foods can be a good value if their quality is very high. When we select foods and when we eat, we use all of our physical senses, including sight, touch, smell, taste, and even hearing. The snap of a potato chip, the crackle of a breakfast cereal, and crunch of celery are textural characteristics, but we also hear them. Food quality detectable by our senses can be divided into three main categories: appearance factors, textural factors, and flavor factors. A Special Book for Food Safety Officer Page 636 QUALITY MANAGEMENT SYSTEM Quality Management System (QMS) focuses on optimizing the quality of the output and no wonder both Quality Assurance (QA) and Quality Control (QC) are the basis of a QMS. Moreover, together with the industry-specific quality legislations and standards, QA and QC make up the structure of the Quality Management System. One of the fundamentals of ISO-9001, “continuous improvement” also suggests that the progress concerning Quality Assurance (QA) never stops. This means that you should always have a critical appraisal of your firm’s Quality Assurance (QA) System to ensure consistent improvements. Quality Assurance The ISO 9000:2015 standard, clause 3.3.6 defines Quality Assurance as: “Part of quality management (3.3.4) focused on providing confidence that quality requirements (3.6.5) will be fulfilled” Quality Assurance (QA) relates to a set of planned activities within the product manufacturing process that ensure the safety and the quality of the product. Quality Control The ISO 9000:2015 standard, clause 3.3.7 defines Quality Control as: “Part of quality management (3.3.4) focused on fulfilling quality requirements (3.6.5)” In other words, Quality Control (QC) refers to the systematic set of processes used to ensure that the product meets the required quality standards. Quality Assurance (QA) is a combination of activities throughout the manufacturing process that ensures the quality of the product. Consequently, Quality Control (QC) is a set of processes used to secure that the product meets the quality requirements. The main point of Quality Assurance (QA) is to prevent any defects before they occur. Therefore, Quality Assurance (QA) is a proactive activity by its nature. On the contrary, Quality Control (QC) aims to identify any possible issues and verify the quality of the output. Inherently, Quality Control (QC) is a reactive activity and it is conducted only after the Quality Assurance (QA). A Special Book for Food Safety Officer Page 637  DIFFERENCE BETWEEN QUALITY ASSURANCE & QUALITY CONTROL QUALITY ASSURANCE (QA) QUALITY CONTROL(QC) Focus PREVENT IDENTIFY & VERIFY To prevent any defects before they To identify any possible issues, and occur when manufacturing the verify the quality of the product or product. output. Nature PROACTIVE REACTIVE Quality Assurance is a proactive Quality Control is a reactive activity activity in nature – looking to reduce and it is completed after the Quality the number of defects by measuring Assurance. the processes. Processes SOPs Testing process Supplier Management Deliverable peer review Training Management Inspections Change Control Product sampling Project audits Documentation Process checklists Duration LONG-TERM SHORT-TERM Quality Assurance (QA) is a medium to Quality Control (QC) is a much long term process within the product shorter-term activity usually at the design period. final stages when the output is produced. A Special Book for Food Safety Officer Page 638  Life Cycle FULL PRODUCTION LIFE CYCLE TESTING LIFE CYCLE Set of QA activities are planned Quality Control (QC) related throughout the whole product procedures are placed at the testing development life cycle. life cycle. Aa a tool MANAGERIAL TOOL OPERATIONAL TOOL Quality Assurance (QA) can be Quality Control (QC) could be an perceived as a managerial tool for operational tool, for identifying and preventing various quality issues. correcting the defects before the products enters the market. Responsibility EVERYONE SPECIFIC PERSONNEL Quality Assurance (QA) requires the The designated testing team is whole team involvement. responsible for the Quality Control (QC) procedures. A Special Book for Food Safety Officer Page 639 QA & QC IN FOOD ANALYSIS & TESTING Quality Assurance in Food Science Food testing is an integral and important part to ensure food safety. FSSAI through its Quality Assurance (QA) Division works towards fulfilling the vision of providing safe and wholesome food to the citizens of our country by strengthening its food testing laboratory infrastructure & capacity building across the country. Quality Assurance Division is responsible for: § Recognition and notification the notified of Primary and Referral laboratories. § Strengthening of country's food testing system through the 72 State Food Testing Laboratories under Central Sector Scheme. § Ensuring availability of approved Food Testing Methods by compilation of testing methods through 'Manuals of Methods of Analysis' with constant updating. § Conducting Food Analyst Examination (FAE) and Junior Analyst Examination (JAE). § Conducting of Targeted Surveillance to ensure food safety in the country. § Organizing training programs for strengthening capacity of the laboratory personnel of State Food, Primary Notified and Referral food testing laboratories. § Partnership with various national and international bodies such as AOAC International, ICMSF for smooth function of activities related to quality assurance. FSSAI has formulated a scheme to provide support to State Food Laboratories for upgrading the laboratory infrastructure along with trained manpower for utilizing the sophisticated test equipment. Six Initiatives of the scheme are given below, 1. Support Mobile Food Labs 2. Strengthen Referral Food Testing Laboratories 3. Strengthen State Food Testing Laboratories 4. Develop food testing culture in schools / colleges 5. Capacity Building of Food Testing Personnel 6. Incentivize States to use facilities available in FSSAI notified private Labs. The 'Scheme to Strengthening of Food Testing Laboratories (SOFTeL)' enable the States/UTs: o To analyse the regulatory and surveillance samples drawn by the FSO within the shortest possible time frame; o To analyse the safety parameters in food samples such as Heavy metals, Pesticide residues, Antibiotic and drug residues and naturally, occurring toxic substances along with Microbiological examination; To ensure compliance of FSSAI standards on food; o To enable the laboratories to achieve ISO 17025 certification through NABL, India; o To become a resource point for training and facility up-gradation for other existing Government / Public Food testing laboratories in the State; and o To introduce online laboratory data management system through Laboratory Information Management System (LIMS). A Special Book for Food Safety Officer Page 640 Quality Control in Food Science Quality control (QC) is not an optional in food processing; neither is it something that is only done by large manufacturers. It is an essential component of any food processing business. The purposes of quality control are: o To protect the customers from dangers (e.g. contaminated foods) and ensure that they get the weight and quality of food that they pay for. o To protect the business from cheating by suppliers, damage to equipment (e.g. stones in raw materials) and false accusations by middlemen, customers or suppliers. o To be sure that food laws operating in a country are complied with. In general, the quality control procedures used should be as simple as possible and only give the required amount of information (too little information means the test has not done its job, too much information and management decisions may be delayed or confused). Quality control is used to predict and control the quality of processed foods. It is no use producing a food, testing it to find the quality and then trying to find a buyer for that particular batch of food. Quality control is used to predict the quality of the processed food and then control the process so that the expected quality is achieved for every batch. This means that quality specifications must be written and agreed with suppliers or sellers and control points must be identified in the process. The food industry developed essentially to provide food products to consumers, allowing them to conveniently and safely cook meals at home. Bringing the farm to the home, and developing new food products, expanding the possibilities of cooking and nutrition. Recent decades have seen increasingly complex demands on the food industry, from the needs of more adventurous, educated, and health-conscious consumers, as well as from the pressures of government health agencies who are increasingly implementing initiatives to address national health problems through diet. The food science industry was born out of these increasingly complex challenges, such as consumers demanding more meat-free and vegan options, governments pressuring food producers to drastically reduce the salt content of their products, our increasing demand for convenience products, and our growing knowledge of the relationship between food and health fuelling a need for food products that meet a multitude of nutrition goals. Food science strives to understand the complex chemistry/biochemistry of food, to address the food industry’s constantly evolving demands. Food science helps to develop new food products that meet the high quality, safety, and nutrition standards that have always been the hallmark of the food industry. A Special Book for Food Safety Officer Page 641 The purpose of quality control in food science In developing new consumable products, the food science industry is required to carry out stringent quality control procedures, primarily, to ensure the safety of the food. Given that the end product is destined for human consumption, it is of utmost importance that products being developed by food science continue to meet high safety standards. Additionally, quality control is vital for ensuring that consumers simply get the product that they expect, in terms of quality, taste, texture, size, shape, shelf life, and smell. This is vital in ensuring food companies retain the trust and loyalty of their customer base. Further to this, quality control is employed by the food science industry to ensure that the food products being developed adhere to the food laws within the countries destined to receive the product. How is quality control carried out in food science? Usually, companies operating within the food science sector follow a regime of processes that ensure the products being developed meet certain quality standards. Quality control can be proactive. It can prevent the detrimental impact of failing quality standards before it happens. Proactive quality control processes are put in place to prevent a defect before it occurs, for example, this could be anything from checking the functioning of machinery, taste testing and visually inspecting food items, to scanning products to check for contamination. The ultimate aim of these activities is to develop production methods of a food item that are reliable and aren’t prone to defects, therefore, creating consistently high-quality food each time. Quality control processes can also be reactive. Processes are implemented by food science companies that have the aim of identifying and correcting a default that would result in a product failing quality control checks. These methods remove faulty items from production runs before they are shipped. Reactive methods can also be used to locate a wider problem in the food production system, alerting scientists to parts of the production that may be failing, or are not reliable enough to produce consistently high-quality products. This helps scientists decide how to develop and evolve their food production methods. It is generally agreed upon that good quality control procedures involve a sophisticated quality management system, one that has been developed to assess quality at each stage of the production process. It is also agreed that successful systems are those where each member of the team holds responsibility for quality control. Often, food quality control systems must meet specific requirements, those laid out by the governing bodies of the country in which the food company is operating in. For example, numerous countries enforce Good Manufacturing Practices (GMP) and the system Hazard Analysis and Critical Control Points (HACCP). These standards can be used to guide companies in their quality control practices by outlining standards that must be met. A Special Book for Food Safety Officer Page 642 Significance of QC Without quality control in food science, the industry would not be able to develop new food products to meet the ever-changing and increasingly complex demands of today’s consumer. Quality control allows scientists to create innovative food items that respond to various needs, as well as continuing to improve the quality of food available to consumers. Therefore, it is vitally important. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx A Special Book for Food Safety Officer Page 643  OUR SELECTION Website: www.swaeducation.com A Special Book for Food Safety Officer Page 644 Connect with us: Youtube.com/Swaeducation.com Swa Education Swaeducation_official Facebook.com/Swaeducation.com A Special Book for Food Safety Officer Page 645