Milk Quality Monitoring And Testing Procedures PDF

Principles of Food and Dairy Sciences course (T 105) Biotechnology Program Students Level (1) BY Dr. OSAMA IBRAHIM ABDEL-SALAM EL BATAWY Prof., Food Science Department, Faculty of Agriculture, Ain Shams University, MONITORING COMPONENTS OF NORMAL MILK AN...

Principles of Food and Dairy Sciences course (T 105) Biotechnology Program Students Level (1) BY Dr. OSAMA IBRAHIM ABDEL-SALAM EL BATAWY Prof., Food Science Department, Faculty of Agriculture, Ain Shams University, MONITORING COMPONENTS OF NORMAL MILK AND ITS QUALITY CONTROL  Milk sampling Appropriate sampling is the primary and basic requirement for monitoring its normal components. The milk in the containers must be thoroughly mixed to have uniform distribution of its milk before a collection of the milk sample. There should be random sampling of the packed milk from shops monitoring its components. (1)  Milk sampling milk for hygienic monitoring ✓ Sampling milk for bacteriological tests require a lot of care. ✓ Containers for sampling are sterilized in an autoclave for 15 min at 120° C to avoid environmental contamination. (2) (VI) ✓ In the field condition, disinfection of the containers can be done with 70% Alcohol swab and washing them in boiled water for 1 minute. (2) (VI)  Preservation of milk samples Milk samples for chemical tests (4) ▪ Milk samples for butter-fat testing may be preserved with chemicals like Potassium dichromate (0.5 ml of 14% solution in 250 ml sample bottle). ▪ Refrigerated milk samples are warmed up to 20ºC in water bath at 40 ºC, homogenized and a sample is then collected monitoring its fat. ▪ Sodium azide can be used at rate of 0.1 percent. ✓ Milk samples can’t be kept waiting at room temperature in the laboratory. ✓ If it can not be processed immediately, it can be stored at freezing temperature till can be processed for analysis. ✓ In field condition, ice box can be used to store samples.  Labeling and records keeping ✓ Milk samples are labeled with name of the farmer, address and date such 1-23112013. ✓ This date is also used as a code for the sample. This information is also recorded on computerized data sheet and dead record register. ✓ The arrangements may be made so as the farmer may be able to see the processing of his milk sample if interested but through window. ✓ The record may be provided to the farmer if he is interested to have.  ORGANOLEPTIC TESTS Introduction (5) ❑ Organo-leptic test rapidly detects poor quality milk at the milk collection point. ❑ Milk grader is required to have good sense of sight, smell and taste. Materials There is no need of any equipment and testing reagent.  Procedure Open can of the milk. Smell the milk immediately. Observe the appearance of the milk. In case the grader is unable to make a clear decision for the quality of milk, then taste the milk. Look at the lid and the container to check its cleanliness.  Comments Abnormal smell and taste may be caused by: 1) Atmospheric smell (methane, or cowy odor). 2) Physiological smell in animal body that might be due to hormonal imbalance, cows in late lactation or spontaneous rancidity of milk. 3) Bacterial products 4) Chemical or bacterial colors in milk. 5) Advanced acidification (pH < 6.4).  CLOT ON BOILING TEST Introduction ✓ Clot on boiling (C.O.B) is quick and simple. ✓ It is one of the old tests for too acid milk (pH