Food Storage and Temperature Control Lecture PDF

The Storage and Temperature Control of Food Linear Workflow of Food Delivery & unload Refrigerate Preparation (raw) Cook Preparation (high-risk)...

The Storage and Temperature Control of Food Linear Workflow of Food Delivery & unload Refrigerate Preparation (raw) Cook Preparation (high-risk) Hot Hold Serve. Delivery and unloading of raw material In the food industry, incoming and outgoing materials need to be properly shipped, received, handled and stored to prevent the risk of biological, chemical or physical hazards. Effective checklist should be in place Deliveries should only be accepted from approved suppliers Deliveries Should all be checked before storage. Delivery vehicle should be clean and, if necessary, refrigerated Outer packaging should be in good condition (not contaminated, e.g. from bird dropping) Food should be of good quality and suitably labelled and date coded. Sufficient shelf-life for it to be used Deliveries Chilled food should be delivered below 5oC Frozen food should be delivered at/below -18oC Food should be checked with calibrated probe thermometer and details recorded Satisfactory deliveries should be moved to storage within 15 min of unloading Deliveries Reject the delivery if: If high risk food is delivered in an unrefrigerated vehicle o Exception: in certain circumstances involving short journeys the temperature of the food should be checked, if below 8oC, it may be accepted Food from unapproved supplier/source Unsatisfactory delivery vehicles Out of date packages Damaged packaging Evidence of pests Chilled food above 8oCFrozen food above -15oC Deliveries Raw food and high-risk food should be completely segregated to avoid risk of contamination No—food items (esp. chemicals), and strong-smelling food which may cause cause taint problems should be delivered separately Delivery records should be filled for accepted food and rejected food, including details of check, e.g. temperature Delivery area should be kept clean, tidy and ready for deliveries  Rejecting item Rejecting deliveries Separate rejected items from accepted items Inform the delivery person about the cause of rejection Obtain a signed adjustment or credit slip Log the incident on the invoice or receiving document  Raw meat and poultry Raw meat should be stored between -1oC and +1oC, and humidity of around 90% Should be kept for up to a week, although processed raw meet and offals have a shorter life Products should not touch the wall surface Only approved suppliers should be used Eggs Raw eggs are source of Salmonella Salmonella maybe present inside the egg or on the shell, esp. if contaminated with chicken faces Should be stored at constant cool temperature below 20oC Fluctuation of temperature may result in condensation on the shell and Salmonella being sucked into the egg from the surface Stock rotation is essential The rule is (First in, first out) Eggs Retailer should label eggs by “sell by” to ensure a minimum of 7 days “best before” date shelf life for the consumer Caterer should: Purchase from reputable supplier In UK: lion-branded eggs and date coded are preferred Store eggs under refrigeration Observe “best before” date Reject: Soiled, cracked and out of date eggs  Meat, pies, pasties and sausage rolls Only approved suppliers Preferably stored under refrigeration - Temperature around 7oC, with good air (pastry remain crisp) Cooked to high temperature 90oC (few bacteria survive) Stock rotation is important and such products should be sold on the day of production or the next day If anything is added to pies or pasties after baking store at or below 5oC Fluctuation of temperature may result in condensation and mold growth (keep constant) Do not store with raw meat or vegetables If sold hot from retail outlets they must be cooked thoroughly  If stored, maintain above 63oC  Or microwaved as required If reheated:  Must be thoroughly reheated in an oven and never in display unit designed only  Fruits and vegetables Although each fruit and vegetable has its own optimal storage condition; A general Guide: If cut or peeled: store under refrigeration (esp. melon and tomato) Tropical fruits (pineapples and bananas): Stored at 10oC to 13oC (to avoid chill injury) Dry stores are used for storage of fruits and vegetables: Avoid warm, moist conditions and condensation (because it encourage bacterial spoilage and mold growth)  Fruits and vegetables Avoid low humidity and excessive ventilation (result in dehydration) Examine fruits for molds regularly Transit wrapping (esp. non-breathing) plastic films may need to be removed to avoid condensation Stock rotation Raw fruits and vegetables are implicated in foodborne outbreaks (Salmonella and E-coli) Examples: Tomatoes, spinach, broccoli, lettuce, cut melon, and raspberries Washing and brushing help to reduce bacteria, soil, dust, insects and some chemicals. However, unlikely to remove  Ice cream Should be kept in clean, dedicated freezer Must not be stored with raw material Always kept frozen Discarded if defrosted Defrosted ice cream is a hazard because if temperature is high enough its ideal nutrient for growth of pathogens such as Salmonella Use tubs completely before new tubs are started Nothing should be placed on top of open tubs Lid should be kept on Texture ice-cream is more temperature sensitive than other frozen food; it may be held at -12oC before use  Milk and Cream Should be stored under refrigeration 5oC Placed in refrigerator or cold store as soon as received Imitation cream should also be refrigerated Crates of milk should not be stored below raw meat.  Flour and Cereal Stored in mobile stainless steel containers Lids must be tight fitting Large stock of flour kept in original sacks must be stored cleared of the ground and free of damp Condensation may result in mold growth on wet flour Regular cleaning of storage containers Frequent inspection Stock rotation Check for rodents and insects  Canned Food Usually kept in dry store, which is cool, well ventilated and free of condensation Stock rotation (esp. can of high acid fruit such as prunes and tomato, may blow if stayed longer than recommended). However, some cans e.g. canned fish in oil maybe kept at least 5 years Check weekly  Remove cans if: Blown, leaked, rusty  Reject cans if: Food discolored, have unusual smell, texture or interior of can is rusty o On opening: Place in the refrigerator in covered container Mold contamination can occur Physical contamination: metals parts Acid food can attack the wall and excessive amount of tin or iron may end up in the food, leading to developing metallic taint  Some meat cans have been pasteurized, therefore store under refrigeration  Wrapping and packaging Wrapping and packaging materials should be stored in clean and dry areas. Cling films Vacuum packing  Unfit food and damaged stock What should you do with unfit food and damaged stock? A. Change the expiry date? B. Give to the needy people? C. Mark clearly and discarded? Codes Stock rotation to ensure older food is used first But some products do not require a ‘use-by’ or ‘best-before’ date. In this case use color coding , color for each day of the week. Food past its “use by date” should be segregated from food intended to for sale Traceability Food business must be able to trace food items or material involved in food production process Should have written system in place (product type, quantity, source, date) Possibility of recalls  Dry-goods store Rooms used for the storage of fruits and vegetables, dried, canned and bottled foods should be kept: o Dry o Cool (temperature 10oC -15oC) o Well lit o Well ventilated o Free from condensation risk o Shelves should be easy to clean non- absorbent o Clean and tidy o Rodent and bird-proofing o Clear of the wall and off the floor: allow cleaning and pest control o Stock rotation o Store non-food items e.g. cleaning equipment's & chemicals away from dry-good stores  Refrigerator Refrigerator and walk-in cold room should be accessible and away from heat sources They should be in well ventilated area, away from direct sun rays High humidity should be avoided: it causes condensation in food Regular maintenance Regular defrosting (if not automatic) Frequent cleaning (at least weekly): warm water and soda bicarbonate maybe used, removes mold and yeast Drip trays should be emptied Dry after cleaning Bring to correct operating temperature before reloading Stock should be kept in back-up chill during cleaning  Operating temperature Optimum temperature for refrigerator is between 1oC & 4oC Cook-chill food with maximum shelf life of 5 days: betw. 0oC & 3oC Maximum legal temperature for high risk food stored in refrigerator is 8oC Cold food on a display food buffet may rise above 8oC on one occasion for up to 4 hours What are the action required if refrigerator display temperature of 12oC ?  Hot food Hot food not intended for rapid consumption should be cooled rapidly Not to be placed immediately into the refrigerator. WHY? Raise the temperature of the refrigerator/stored food Increase ice build-up Condensation may also occur, resulting in an unacceptable drip on stored food below  Contamination o Avoid contamination o Label o Adequately cover  Packing and rotation of food Do not overload refrigerator Allow good air circulation 3 cm gap should be allowed between stored trays Stock rotation of food items in the refrigerator (slow growth of Listeria monocytogens) Soft cheese and pate have been associated with Listeria monocytogens The storage life of perishable food under refrigeration Shelf life varies according to operating temp. and type of food Example: At 1oC: Most vegetables will keep at least two weeks Butter two months Fresh beef 1 week Chilled display cabinets Load correctly Load line should not be exceeded Should be away form heat  Temperature monitoring Monitor cabinet thermometer readings regularly using digital or infrared thermometer Record temperature at least twice a day Monitoring temperature of the food Keep temperature record or data logger print out Thermometer  Digital probe Thermometer Monitoring hot and cold Must be cleaned and disinfected Calibrated (ice and boiling water)  Common errors with using digital probe thermometer Failing to clean and disinfect before using Not allowing sufficient time for an accurate reading Not taking the core temperature Not using calibrated thermometer Taking false temperature (touching bones or side container)  Infrared thermometer  Cooking Core temperature 75oC A disinfected digital probe thermometer should be used to check core temperature Correct cooking indicator: o Color and texture changes (no pink bits) o Juices of poultry running clear Cooked food should (unless immediately cooled), be kept hot at or above 63oC, or served for immediate consumption Hot food on a display food buffet is allowed to fall below 63oC for maximum period at once of up to 2 hours  Microwave Often used for cooking and reheating food o Advantage: quick o Disadvantage: risk of cold spots (growth of bacteria) Bloody chicken indicates undercooking, the chicken should be replaced Usual reason for undercooking chicken:  Inadequate thawing time  Inadequate cooking time for the size of the chicken  Defective oven What should the internal cooking temp. of chicken should be? How to check?  Cooling of hot food Rapid cooling of hot food to be chilled or frozen is important to prevent spore germination or multiplication of surviving pathogens Recommended: cool food below 10oC in less than 1.5 hours FDA regulation: Cool joints from 60ºC to 21ºC in 2 hours, and from 21ºC to 7ºC within further 4 hours Ice water baths cool faster than cold air Large quantities of liquid (e.g. gravies), intended for reheating are ideal for anaerobic spore-forming bacteria Food poisoning o Problems with large quantities: Cool spots during cooking or reheating Failure to stir Base of the pan being bigger than the heat source Uneven distribution of heat Cooling rules: Minimize bulk: the smaller the size of food the faster it will cool. Maximize surface area ( use square or rectangular containers) Shallow containers rather than deep containers Fanning: 10 cm away ( food should be covered) Blast chillers: equipment for rapid chilling of food. chilled air 2ºC to 7ºC  Methods for cooling food Effective methods for cooling food quickly and safely Ice-water bath Blast chiller Ice paddle Ice or cold water as ingredient  Methods for cooling food The following factors affect how quickly the food will cool Thickness or density of the food The denser the food, the slower it will cool Size of the food The larger the amount the slower it will cool Storage container Stainless steel transfer heat away from food faster than plastic. Shallow pans let the heat disperse faster the deeper ones  Food preparation Equipment Make sure workstations, cutting boards and utensils are cleaned and sanitized Quantity Only remove as much as food from the cooler as you can prep in a short period of time Storage Return prepped food to the cooler or cook it just prior to consumption  Food service Food covers and sneeze guards Cover food and install sneeze guards to protect food from contaminants Covers protect food from contamination and help maintain food temperatures Food in display should be kept:sneeze guards Hot: at or above 63ºC Cold: below 5ºC  Service Staff Guidelines for Serving Food Handling dishes and glassware Correct Incorrect  Storage of frozen food At -40oC: frozen food can be kept for years without noticeable deterioration However, most catering & retail freezers operate at -18oC: gradual loss of flavor and toughing of texture Frozen food should meet the following: Use approved suppliers Reject deliveries above -15oC or showing signs or thawing Do not keep unrefrigerated more than 15 minutes Do not use display freezer for freezing fresh food Do not fill fill display above limit Regular inspection Freezer door opened as minimum as possible Effective stock control and stock rotation system Freezing and refreezing Ice crystals formation e. g. ice crystals formed in ice cream which has been refrozen Food which has been frozen, thawed and thoroughly cooked maybe refrozen quite safely although flavors and texture will be altered and nutritional value lowered Thawing of frozen food Poultry, joints of meat should be thoroughly thawed NEVER thaw food at room temperature (25ºC-30ºC) Thaw food in the following ways Refrigeration Thaw food in a cooler at 5ºC or lower Separate from other food to avoid drip Thawing of frozen poultry is best in a Thawing cabinet or at 10ºC to 15ºC in well ventilated area  Thawing of frozen food Running water Requirement: 1. Submerge food under cold running water 2. Care must be taken (poultry) to avoid contamination of the sink & surrounding surfaces 3. The flow of the water must be strong enough to wash loose food bits into the drain 4. Always use a clean and sanitized food-prep sink when thawing food this way  Cook-chill Process Portioning Storage at Distribution Regenerati Bulk Cooking at Blast Preparation Packaging or below at or below on to at Serving Storage least 75oC chilling Labeling 3oC 3oC least 75oC  Cook-chill rules Good quality raw material Good design linear workflow to avoid cross-contamination Controlled thawing of frozen ingredient Implantation of HACCP system High standards of personal hygiene Food cooked without delay to internal temperature of 75ºC Food portioned and chilled to below 3ºC within 2 hours of cooking Hygienic food containers with date marked Refrigeration between 0-3ºC Maximum life of 5 days (including day of production and day of consumption) If temp. of food exceeds 5ºC it should be eaten within 12 hours, if it exceeds 10ºC during storage or distribution it should be destroyed Refrigerated vehicle for distribution Service should be within 15 min and temp. should not drop below 63ºC Sous vide Cooking raw or par-cooked food in a sealed pouch under vacuum Core temp. as high as 95ºC for 2 min Should be blast chilled to below 3ºC within 2 hours of cooking In UK: storage of 8 days is the maximum recommended Risks: Anaerobic bacteria, spore-forming bacteria, e.g. Clostridium Botulinum  Cook-freeze Similar to Cook-chill (same first 4 stages) Include blast freezing in blast freezers (reduces temp. to -20ºC in less than 90 minutes) Rapid freezing prevent the formation of ice crystals which result in poor texture and loss of nutritional value Keep frozen containers at -20ºC Cook-freeze process Portioning Storage at Distribution Regenerati Bulk Cooking at Freeze Preparation or below at or below on to at Serving Storage least 75oC Packaging chilling 3oC 3oC least 75oC Labeling  Reheating and holding Reheating is a major potential hazard Food should be reheated rapidly to at least 75oC then held at 63oC or above until serving Tools for reheating: Specialist regeneration oven Microwave (industrial, domestic should not be used in commercial practice) Boil liquid products (e.g. soups) for several minutes. Cool before serving to prevent scalding  Hot holding Keeping food hot, pending service bains-marie Liquids, semi liquids, vegetable and ready-to-eat meat can be kept in bains-marie Bring to operating temperature before use Should not be used for reheating Hot cupboard and hot plates May be used for storing reheated products o Monitor temp. every 2 hours o Food below 63oC, maybe reheated once and stored above 63oC or consumed o Hot food below 63oC for longer than 2 hours should be discarded  Supervisor Role Implementing policy of storage and temperature control and HACCP plan Communicate procedure correctly to staff Staff need training Monitor correct implementation of procedure (e.g. stock rotation) Documentation Corrective actions and compliance Monitor traceability Thank You