Food Safety in Dairy Industry

Created by Team Pravara (DT Students)

What is food safety in dairy industry?

Food is only good for us when it is safe otherwise it can create huge problem. Milk is highly nutritious food that is ideally suited for growth of pathogenic and non-pathogenic organisms. Raw milk contains number of dangerous pathogenic organisms. This type of milk is obviously not safe for human consumption. Thus, food safety means to make the unsafe milk absolutely safe for human consumption and after consumption of the milk consumer should not fall ill or feel bad. In large scale, this can be only possible in dairy industry by adopting some advance techniques like pasteurization, ultra high temperature (UHT) treatment of milk and by following strict rules and regulations regarding hygiene, cleaning and sanitization of the plant. In this regard dairy industries can follow any food safety standards and system of National and International Standard Regulation Authorities. In India, the most important Organization is FSSAI (Food Safety and Standards Authority of India). It is an autonomous body established under Ministry of Health and Family Welfare, Govt. of India in 2006. It is mandatory for any

Food Business Operator (FBO) starting from a small sweets shop owner to big dairy industries like AMUL to take food license from FSSAI. One central license is to be valid for five years and after the tenure, food industry has to renew its license. During this period, any product of any company can be picked up from market at any time and checked by the FSSAI approved laboratory. After testing if any food product is found faulty in terms of food safety, the company's license can be cancelled instantly and legal action also can be prosecuted against the company. So day by day food safety laws has become very strict taking into consideration the consumer food safety matter very seriously.

List of outbreaks related to dairy industries

  • Moringa milk arsenic poisoning in 1955: It occured in Japan due to presence of arsenic in milk powder used to feed infants by Moringa Milk Industry.

  • Listeria outbreak in cheese in California in 1985 due to presence of Listeria organism.

  • Salmonellosis outbreak in milk in United States in 1985.

  • Salmonella in ice cream in USA in 1994 due to faulty pasteurization.

  • Chinese milk scandal in 2008: Melamine found in baby food.

What is food hazards?

Food hazards generally mean those microbiological and chemical agents make milk unsafe for human consumption. They can be grouped into following three categories:

1. Microbiological Hazards: Since, milk is an excellent medium for the growth of micro-organisms, dairy products are susceptible to microbiological hazards. Modern methods of control of food borne disease depends on the detection of causative micro-organisms coming from cattle, human handlers, feeds, soils, environment etc.

2. Chemical Hazards: Residues of animal drugs - sulfa drug, sulfamethazine antibiotics like penicillin, tetracycline cause health hazard and violation of regulatory concern. Other chemical contaminants are pesticides used on crops which are used as fodder for dairy cattle and chemical germicidals like iodophores, hypochlorites etc. used in dairy industry for cleaning and sanitization purposes. Dishonest traders intentionally add several chemicals contaminants like urea, starch, caustic soda, maltodextrin, ammonium compounds, vegetable oils etc. to make more profit. These chemical contaminants are considered very critical hazards because once they get entry into milk, this is almost impossible to eliminate them. In this case, we have to keep strict vigilance on the quality of milk.

3. Functional Hazards: Functional hazards are very important to the processor. If a package is slack filled, a product has a poor taste or appearance. This is quite unappetizing and dissatisfied customers will surely complain to the manufacturer.

How to eliminate the pathogenic micro-organisms from milk?

The two most common methods used in dairy industry to destroy the pathogens and non-pathogens in milk are as follows:

  1. By Pasteurization: Heating milk at 72 deg.C for 15 sec. and cooling the milk immediately after heating below 5 deg.C. This is called pasteurized milk and it is safe for two days stored below 5 deg.C.

  2. By Ultra High Temperature (UHT) Treatment: Heating milk at 135 to 150 deg.C for 1 to 3 sec. and in this case there is no need of cooling milk below 5 deg.C. This milk is called UHT milk and it remains safe for consumption for six months when stored at ambient temperature.

So, this is mandatory to declare the shelf-life of particular milk on the label of the packet to make the consumer alert regarding the safety of the milk.

Are you thinking that the heat treatment is sufficient for food safety? Answer will be certainly, no because when we are talking about microbiological contamination of milk, we have to think about following two terms:

  1. Pre-processing Contamination: Contamination of milk before heat treatment - this is not a problem at all because all mico-organisms are eliminated by heat treatment.

  2. Post-processing Contamination: There is always chance of contamination of milk by micro-organisms after processing or heat treatment when we are not following proper cleaning and sanitization method and personnel hygiene in plant. In this case, the particular micro-organism coliform bacteria specially Escherichia coli plays an important role as its presence in milk indicates the improper cleaning and sanitization methods and unh