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Milk PowerPoint Presentation

Milk

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Milk

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  1. Milk

  2. Definitions ‘Raw milk’ means milk produced by the secretion of the mammary gland of farmed animals that has not been heated to more than 40 °C or undergone any treatment that has an equivalent effect. ‘Milk production holding’ means an establishment where one or more farmed animals are kept to produce milk with a view to placing it on the market as food. ‘Dairy products’ means processed products resulting from the processing of raw milk or from the further processing of such processed products.

  3. HEALTH REQUIREMENTS FOR RAW MILK AND COLOSTRUMPRODUCTION Raw milk and colostrum must come from animals: do not show any symptoms of infectious diseases communicable to humans through milk and colostrum; are in a good general state of health, present no sign of disease that might result in the contamination of milk and colostrum are not suffering from any infection of the genital tract with discharge, enteritis with diarrhoea and fever, or a recognisable inflammation of the udder; do not have any udder wound likely to affect the milk and colostrum; to which no unauthorised substances or products have been administered and that have not undergone illegal treatment, if authorised products or substances have been administered, the withdrawal periods prescribed for these products or substances have been observed.

  4. HEALTH REQUIREMENTS FOR RAW MILK AND COLOSTRUMPRODUCTION Brucellosis, raw milk and colostrum must come from: cows or buffaloes belonging to a herd which is free or officially free of brucellosis; sheep or goats belonging to a holding officially free or free of brucellosis or females of other species susceptible to brucellosis, to herds regularly checked for that disease under a control plan that the competent authority approved. Tuberculosis, raw milk and colostrum must come from: cows or buffaloes belonging to a herd which is officially free of tuberculosis; or females of other species susceptible to tuberculosis, to herds regularly checked for this disease under a control plan that the competent authority approved. If goats are kept together with cows, such goats must be inspected and tested for tuberculosis.

  5. HYGIENE OF MILK AND COLOSTRUM PRODUCTION HOLDINGS Requirements for premises and equipment 1. Milking equipment and premises where milk and colostrum are stored, handled or cooled must be located and constructed so as to limit the risk of contamination of milk and colostrum. 2. Premises for the storage of milk and colostrum must be protected against vermin, have adequate separation from premises where animals are housed and, where necessary to meet the requirements, have suitable refrigeration equipment.

  6. HYGIENE OF MILK AND COLOSTRUM PRODUCTION HOLDINGS 3. Surfaces of equipment that are intended to come into contact with milk and colostrum (utensils, containers, tanks, etc. intended for milking, collection or transport) must be easy to clean and, where necessary, disinfect and must be maintained in a sound condition. This requires the use of smooth, washable and non-toxic materials. 4. After use, such surfaces must be cleaned and, where necessary, disinfected. After each transport, or after each series of transports when the period of time between unloading and the following loading is very short, but in all cases at least once a day, containers and tanks used for the transport of milk and colostrum must be cleaned and disinfected in an appropriate manner before re-use

  7. Hygiene during milking, collection and transport Milking must be carried out hygienically, ensuring in particular: before milking starts, the teats, udder and adjacent parts are clean; milk and colostrum from each animal is checked for organoleptic or physico-chemical abnormalities milk and colostrum from animals showing clinical signs of udder disease are not used for human consumption otherwise than in accordance with the instructions of a veterinarian; milk and colostrum obtained from such animals before the end of the prescribed withdrawal period are not used for human consumption; and teat dips or sprays are used only after authorisation or registration colostrum is milked separately and not mixed together with raw milk.

  8. Hygiene during milking, collection and transport Staff hygiene 1. Persons performing milking and/or handling raw milk must wear suitable clean clothes. 2. Persons performing milking must maintain a high degree of personal cleanliness. Suitable facilities must be available near the place of milking to enable persons performing milking and handling raw milk to wash their hands and arms.

  9. Hygiene during milking, collection and transport Immediately after milking, milk and colostrum must be held in a clean place designed and equipped to avoid contamination. Milk must be cooled immediately to not more than 8 °C in the case of daily collection, or not more than 6 °C if collection is not daily;

  10. Filtering of milk During milking different contaminating materials may get into milk (epithelium, fur, feed etc) so it has to be filtered. Dirt →indicate high microbial contamination Removing visible contaminating materials As quick as possible after milking Disadvantages: contaminating materials are comminuted→microbe count↑ Paper filters

  11. Refrigeration Essential for maintaining the original quality of milk: It stops or inhibits (reduce the rate) bacterial growth prolongs the non specific inhibitory effects of the milk and prevents changes in the constituents of milk used for processing. Growing of microbes influenced by: Initial cell count Quality and kind of microbes Temperature of milk Milk from healthy animal: 103-104 bacteria/ml

  12. Changes of microbe count at different storage temperature

  13. Refrigeration Quickly With slow stirring to save lecitine cover of the fatdrops →lipase →rancid taste Flash cooling Storage

  14. Hygiene during milking, collection and transport During transport the cold chain must be maintained and, on arrival at the establishment of destination, the temperature of the milk must not be more than 10 °C.

  15. Hygiene requirements of transportation Clean, intact, odourless Disapproved quality milk must not be filled into the tank Prohibited to use it for other purposes Compartments of the tank should be emptied separately Hose (cleaning, disinfection) Workers personal hygiene

  16. Transportation • Bulk tank is divided into 2-5 parts • Double layer • Reqiurements of bulk tank: • Temperature and amount of milk can be measured • Sample taken at reception • Documentation • Empty totally • Cells, tubes, surfaces desinfiction and cleaning

  17. Reception of milk Quantitative reception Volume or weight Qualitative reception Phisycal-chemical-microbiological parameters Temperature Organoleptic properties pH value or acid degree Physical purity Density Inner substances (fat, protein, solids- non fat content) Antibiotic residues Freezing point Somatic cell count Microbe count

  18. Reception of milk Plant and raw milk qualifying laboratories Arriving in the plant, the temperature of milk ≤ 10 °C Organoleptic inspection Sourness, curdling, taste-, colour-, odour-deffects of milk Acid degree Density (1029-1033 g/cm3) Freezing point (foreign water)

  19. Reception of milk, Antibiotic residues • ≥MRL → prohibited to use for human consumption, feed, milk products • (allergy, starter cultures are inhibited)

  20. Reception of milk Somatic cell Indicates secretion status, case of mastitis Total count Indicates of milking and handling hygiene Detection of total count Fast microbiological methods

  21. Prestorage Stainless Steel Dairy Milk Silo (30 000-200 000 l) Electrical mixer ≤ 6 °C Hygiene requirements: Technological suitability, working properly, Intact inner surface Continuous temperature registration Ventillation filter hygiene Filling rate, Cleaning, desinfection, continuous checking

  22. CRITERIA FOR RAW MILK AND COLOSTRUM A representative number of samples of raw milk and colostrum collected from milk production holdings taken by random sampling (must be checked) The checks may be carried out by, or on behalf of: the food business operator producing the milk; the food business operator collecting or processing the milk; a group of food business operators; or in the context of a national or regional control scheme.

  23. CRITERIA FOR RAW MILK AND COLOSTRUM • (*) Rolling geometric average over a two-month period, with at least two samples per month. • (**) Rolling geometric average over a three-month period, with at least one sample per month, unless the competent authority specifies another methodology to take account of seasonal variations in production levels.

  24. However, if raw milk from species other than cows is intended for the manufacture of products made with raw milk by a process that does not involve any heat treatment, food business operators must take steps to ensure that the raw milk used meets the following criteria: Plate count at 30 °C (per ml) ≤ 500 000 (*) Somatic cell ≤1.500 000 cell/ml (*) Rolling geometric average over a two-month period, with at least two samples per month.

  25. Food business operators need not comply with the temperature requirements : (a) the milk is processed within two hours of milking; or (b) a higher temperature is necessary for technological reasons related to the manufacture of certain dairy products and the competent authority so authorises.

  26. REQUIREMENTS CONCERNING DAIRY ANDCOLOSTRUM-BASED PRODUCTS TEMPERATURE REQUIREMENTS Food business operators must ensure that, upon acceptance at a processing establishment, milk is quickly cooled to not more than 6 °C; and kept at that temperature until processed. However, food business operators may keep milk and colostrum at a higher temperature if: (a) processing begins immediately after milking, or within four hours of acceptance at the processing establishment; or (b) the competent authority authorises a higher temperature for technological reasons concerning the manufacture of certain dairy or colostrum-based products.

  27. REQUIREMENTS FOR HEAT TREATMENT Pasteurisation is achieved by a treatment involving: (i) high temperature for a short time (at least 72 °C for 15 seconds); (ii) low temperature for a long time (at least 63 °C for 30 minutes); or (iii) any other combination of time-temperature conditions to obtain an equivalent effect, such that the products show, where applicable, a negative reaction to an alkaline phosphatase test immediately after such treatment.

  28. REQUIREMENTS FOR HEAT TREATMENT • Ultra high temperature (UHT) treatment is achieved by a treatment: • involving a continuous flow of heat at a high temperature for a short time (not less than 135 °C in combination with a suitable holding time) such that there are no viable microorganisms or spores capable of growing in the treated product when kept in an aseptic closed container at ambient temperature, and • sufficient to ensure that the products remain microbiologically stable after incubating for 15 days at 30 oC in closed containers or for seven days at 55 oC in closed containers or after any other method demonstrating that the appropriate heat treatment has been applied.

  29. Heat treatments

  30. Cleaning and disinfections in milk industry Types of contamination From milk components (fat, lactose, protein, minerals) Milkstone is a complex heterogeneous mixture of organic and inorganic substances which adhere tenaciously to milk heating surfaces. It is a substance closely related to boiler scale in steam generators, the relationship being that both are the result of heat treatment. The hard-water minerals cause boiler scale in a manner similar to the formation of milkstone by the mineral salts of milk.

  31. Cleaning and disinfections in milk industry Scale CaCO3, Fe, SO4, Transport vehicles Dust, mud, oils etc. Surfaces Stainless steel Aluminium Plastic

  32. Cleaning and disinfection procedures 5 PHASES Rinsing: Wet the surface, milk residues are partly removed, Low fat content (sour milk products): 30 °C High fat content (butter, cream): 40-50 °C Chemical washing Required concentration 60-65 °C Rinsing Disinfection Steam, hot water, disinfecting agents Rising (remove chemicals)

  33. Technology of cleaning and disinfections Manual or automatic Manual: disassembled instruments In the closed milk processing systems, the containers are cleaned by means of CIP. CIP – 'Cleaning in Place' – refers to the automatic cleaning processes which run in a circuit within a production plant without the plant or its components having to be disassembled.

  34. Technology of cleaning and disinfections • CIP is designed either as no-recovery/single use or as a recovery system. In the "no-recovery system", the cleaning solution is pumped from the batch tank into the CIP circuit and discarded after the cleaning step. In cleaning with recovery, on the other hand, the chemically and biologically active ingredients are pumped in a circuit from the CIP system through the piping into the production plant and back into the recovery tanks. The cleaning media involved – with the addition of fresh media - can be used several times.