Food Quality Control: An Introduction

Introduction to Food Quality Control

• Food quality control maintains quality within acceptable levels and minimizes vendor costs.
• Food quality control utilizes technological, physical, chemical, microbiological, nutritional, and sensory parameters.
• Quality attributes assessed are sensory properties (flavor, color, aroma, taste, texture) and quantitative properties (sugar, protein, fiber content), and hidden attributes (peroxides, free fatty acids, enzymes).
• Consumer protection is the primary and ultimate goal of food quality control
• Food laws and regulations cover marketing, production, labeling, food additives, dietary supplements, GMP, HACCP, federal laws/regulations, and inspections to standardize procedures.

History of Food Quality Control

• Around 2500 BC, Mosaic and Egyptian laws addressed meat contamination
• Around 2000 years ago, India had regulations against grain and fat adulteration
• Laws of Moses contained decrees on food similar to modern food laws
• The Old Testament prohibited meat consumption from animals not intentionally slaughtered.
• Ancient food regulations existed in Chinese, Hindu, Greek, and Roman cultures
• Athens controlled beer and inspected wines to ensure purity
• Roman government controlled food to protect consumers from poor quality and fraud
• Trade guilds in European communities supervised member integrity and product quality
• In 1419, a proclamation prohibited wine adulteration of wine from different regions
• A Commonwealth statute regulated butter quality in 1649
• France's Livre des Métiers outlined trade guild practices in the thirteenth century
• Chemistry was used to fight food adulteration in the seventeenth and eighteenth centuries
• Robert Boyle used specific gravity principles to detect food adulteration scientifically

Industrial Revolution in the Nineteenth Century

• Standardization developed in the second half of the nineteenth century due to industrial growth
• Uniform measures for length and weight were pursued, with the acceptance of the meter and kilogram as standards in the 1870s.
• The industrial revolution had significant impacts on food production, regulations, and control
• Public health issues arose in industrialized centers due to rapid urbanization and factory systems
• Overcrowding and unhygienic conditions prompted calls for public health reform and improved food supplies
• Friederich Accum's Treatise on Adulteration of Foods and Culinary Poisons (1820) revealed fraudulent practices in England
• A municipal service for food and beverage control was established in Amsterdam in 1858
• England enacted the first comprehensive modern food law, "An Act to Prevent the Adulteration of Food and Drink," in 1860
• The act provided a scientific approach to food problems by appointing an analyst to assess food purity
• A municipal service for drinking water control was established in Budapest, Hungary, seven years later
• Similar laws emerged in Belgium, Italy, Austria, Hungary, and Scandinavian countries
• The volume of activity in institutions led to the control of 176,000 food samples, of which 11,000 were adulterated in Massachusetts (1882-1907)
• Australia, Canada, and the US passed food regulations

The Twentieth Century

• India amended food adulteration controls (1919-1941) and enacted the Prevention of Food Adulteration Act in 1954
• Food control was slow to emerge in the Far East until the 1940s-1960s
• Latin American countries enacted food laws with differences in legal systems based on Spain and Portugal
• Independent African states emerging in the late 1950s were influenced by European food control services
• French territories adopted French food enactments, while British territories followed British procedures
• Factors such as corruption and lack of visionary leadership have contributed to many African countries' inability to make reasonable headway
• There is a lack of skilled personnel to create suitable food laws, along with shortages of equipment and materials

Definitions of Food Quality Terms

• Quality control monitors processes and prevents non-conformity, as well as assuring a standard of excellence and correcting defects
• Product quality conforms to specific standards or specifications
• Food quality control ensures food protects consumers at all processes of production
• Food quality assurance involves planned actions to provide confidence in product quality, prevent defects, and is a proactive process
• Food hygiene includes conditions and measures ensuring food safety and suitability at all stages of the food chain
• Good hygienic practices involve practices regarding the conditions and measures needed to ensure the safety and suitability of food at all stages of the food chain
• Quality assurance is a process oriented and focuses on defect prevention and Quality control is product oriented and focuses on defect identification

Importance and Objectives of Food Quality Control

• Food quality control ensures consumers eat and handle safe food
• Food quality control protects customers from contaminated foods, ensures correct weight and quality
• Food quality control protects businesses from unreliable suppliers and false quality accusations
• Food quality control ensures food laws are met and regulations are followed
• The objectives of food quality control include evaluation of quality standards, judging product conformity, evaluating optimum quality, improving quality through experimentation, good vendor relations, and developing quality consciousness.

Food Supply Chain

• The food supply chain involves the peasant household, processing industry, distribution center, wholesaler, retailer, and consumer
• The food supply chain comprises five links: product material supplying, production processing, packing storage and transporting, sale, and consumer expending
• The food supply chain is a networked structure composed of physical, information, finance, technical, standardized, security, and value-added connections

Quality Procedures and Food Contamination

• Food is unavoidably exposed to hazards along the supply chain
• Risk factors at each supply chain phase help to ensure an effective quality system
• Steps of the supply chain must be carried out strictly, with care, and according to standard procedures
• Potential risks, responsibilities, and their best solutions must be explored at each supply chain phase
• Food contamination can be physical, chemical, microbiological, or due to other contaminants
• Adulteration is a major physical contamination, mixing inferior quality with a superior product
• Adulteration reduces taste, color, odor, and nutritional value
• Adulteration provides advantage and profits for the adulterator
• Food products prone to adulteration include spices, milk, edible oil, beverages, sweets, pulses, sugar, processed foods, rice, and cereal products
• Chemical contamination involves toxic chemicals that elicit harmful effects when consumed
• Chemicals in food production can affect quality and disguise deterioration
• Food additives like coloring matter, preservatives, artificial sweeteners, antioxidants, emulsifiers/stabilizers, and flavor enhancers should be of approved quality
• Microbiological contamination of food is a prevalent health problem
• Microbiological criteria should be established to ensure good quality and safe food
• Freedom from pathogenic microorganisms must be ensured in raw materials, ingredients, and finished products at any stage
• Microbiological examination of food products must be adopted widely, with established criteria to define food acceptability
• Food poisoning is often results from consumption of old, used, residual, fermented, or spoiled food
• The enterococcus streptococcus faecalis causes Gastroenteritis
• Clostridium perfringens contaminates inadequately refrigerated food and causes food poisoning
• Bacillus cereus is reported to be the etiologic agent in numerous food poisoning outbreaks
• Aflatoxin causes liver cancer and Flavism (hemolytic anemia) and Lathyrism is a disease, which paralyses the lower limbs.

Other Food Contaminants

• Metals are often unintentional contaminants of food and are toxic when present beyond trace amounts
• Metals enter food through air, water, soil, industrial pollution and utensils
• Enamelware of poor quality contributes antimony and galvanized utensils leach zinc
• Tin plate used for containers is a major source of tin contamination
• Copper from aluminum utensils is an essential trace element for the human body but its contamination is toxic
• Fumigants may contaminate food by reacting with food constituents, producing or destroying essential nutrients
• For example, ethylene oxide reacts with inorganic chloride to form ethylene chloro hydride, which is toxic
• Solvents used for oil extraction may react with the foodstuff, forming toxic products
• During processing, lipids may undergo changes, decreasing product value

Methods of Food Quality Control

• Food manufacturers have realized that competition in a global market requires continual improvement of product and service quality
• They follow the process improvement cycle: PLAN (plan improvement), DO (implement plan), CHECK (analyze data), and ACT (take action)
• The quality control process consists of raw materials, in-process elements, product, and service.
• Major factors causing variability in finished product quality are people, equipment, and methods/technologies.
• Proper statistical process control methods are vital for product quality assurance.
• The value of quality characteristics is used to provide feedback on how processes may be improved.
• Statistical quality control measures the finished product, samples over days/weeks, and accepts or rejects lots based on sample information
• Statistical process control methods identify factors in the process variability, eliminating their effects before a worse product is manufactured
• Control charts provide on-line feedback of information about the process.
• Public health authorities have been concerned with filth and foul odors in urban areas.
• The first early inspection systems, based on sensory evaluations, were legally enforced at the beginning of the 20th century
• Initial bacteriological techniques detected pathogenic bacteria in foods
• The food and beverage industry have applied stricter product inspection procedures and more effective production methods to conserve the freshness of raw materials.
• The establishment of Good Manufacturing Practices (GMP) and Good Hygienic Practices (GHP) in many countries has significantly reduced the risk of spoilage and pathogenic microorganisms in modern food products.
• In addition to compliance with national and international food regulations, food manufacturers follow international quality standards (ISO, HACCP)
• In recent years, there has been increased focus on traceability in food production

Rapid Methods of Food Quality Control

• Ion mobility spectrometry (IMS) or differential mobility spectrometry (DMS) identifies and quantifies analytes with high sensitivity including storage, process and quality control as well as the characterization of food stuffs
• Electronic-nose comprises an array of electronic chemical sensors and a pattern recognition system. This method has other applications too, including uses to detect bacterial growth on foods, freshness of fish, process control of cheese, sausage, beer and bread, and detection of off-flavors in milk and dairy products.
• Immunochemical methods are based on antigen–antibody interaction to enhance the detectability of the analyte in an amplification step. E. Coli, Clostridium, Salmonella, and Shigella have also been similarly detected.
• Enzyme Immunoassay (EIA) detects unique protein carbohydrate markers located within the body or the flagella of the cell.
• Biosensors comprise a biological sensing element coupled to a transducer for signal processing to detect unwanted microbial activity or the presence of a biologically active compound. Examples are glucose and pesticides for food.
• Flow cytometry (FCM) achieves specific detection of pathogenic strains using immunofluorescence techniques allowing microorganism detection at the single-cell level also differentiating the viable non-culturable (VBNC) form of bacteria from healthy cultivable cells.
• Polymerase chain reaction (PCR) isolates DNA, amplifies target sequences, separates amplification products by agarose gel electrophoresis, estimates fragment size using ethidium bromide, and verification of results by cleavage/sequencing
• Pulsed-field gel electrophoresis (PFGE) is a restriction-based typing method that separates DNA fragments and provides a DNA "fingerprint"
• Magnetic separation separates Salmonella from food and faecal matter using myeloma protein and hybrid antibody, and is used to test milk yogurt and meat and vegetables, and to detect and isolate the specific protein of S. aureus.
• Near-infrared (NIR) spectroscopy has key benefits, high speed, requires no complex sample preparation or processing, has low cost, and is suitable for on-line process monitoring and quality control.
• X-ray is a newer technology started making into roads in the food industry in the early 1990s. It can also be used to detect contamination like glass, bone, rubber, stone or plastic. It quickly and consistently identifies substandard products.
• Computer vision consists of an illumination source, an image acquisition device, processing hardware, and software modules. They provide fast identification and analysis of food surfaces.

Food Quality Parameters

• Key food quality parameters include the production method, place, trace-ability of the ingredients, safety, nutritional value, sensory properties, functional properties, and the biological value

Areas for Food Quality Control

• Domestic food production and distribution; involve use of improved agricultural techniques with consequence in environment Includes: soil contamination with pesticides and other residues and the use of agricultural and veterinary chemicals, residual effects, microbial /chemicals, and food processing hazards/ poor manufacturing transport or storage
• Food imports and exports

Challenges for Food Control Authorities

• Increasing incidences of foodborne illness and emergence of new foodborne hazards
• Rapid growth of advanced technologies in food production, processing, and marketing
• Application of science-based food control systems focusing on consumer protection
• Global increase in food trade and harmonization of food safety and quality standards
• Changes in education standard awareness and lifestyles, including rapid urbanization
• Growing consumer awareness of food safety and quality issues

Food Quality Assurance Objectives

• Quality assurance is an on-going, broad effort applied daily to prevent defects proactively, and accounts for both worker and management interest
• Needs documentation of all processes and procedures
• It's effective QA system makes decisions on how the system should operate. As well as being straight forward, concise and simple, and practical to save time and costs.
• Also uses the data generated and be confident with them to make a manual
• It has a quality Assurance manual to describe the policies of the organization, objectives, functional activities, and specific QA
• The Main Components of Quality assurance include: implementation by cooperative effort, orderly prevention, periodic assessment, and corrections
• The major features of Quality Assurance include Management who handles responsibilities such as creating and monitoring the QA program. QA formulates a plan and is responsible for the QA plan adherence, and provides expertise. Lastly the analyst is responsible for the details.