Milk is a universal nutrient consumed by millions of people without distinction of social or economic class. The Indian milk market has matured well beyond the Amul brand, which was launched by a farmers coop, promoted by Dr Kurian to usher in milk revolution. While in the semi-urban and rural areas loose milk is largely distributed by local sellers, in larger cities and metropolitan towns a number of branded suppliers have established a distribution network. Consumers have concerns regarding adulteration (with water, vegetable oils, detergents, caustic soda, urea, starch, blotting paper, white paint and so on). There are concerns regarding packaged brands too. Consumer Voice carried out comparative tests of nine leading brands of packaged milk. The test, carried out at an NABL accredited lab, shows that most of the packaged milk brands are safe. These test results have put to rest consumer concerns about packaged milk.
Test criteria: Consumer Voice tested nine popular brands of packaged toned milk on a range of quality, safety and acceptability parameters. Milk is expected to be high in fat content as well as milk solids not fat (SNF), which is an indicator of the quality of milk. Hence, the test parameters included quality of milk fat, milk solids not fat, saturated fat, cholesterol, calcium and vitamin A. The brands were further subjected to adulteration, safety and acceptability tests i.e. neutralisers, detergent, urea, caustic soda, formaldehyde and melamine, microbiological tests, tests for lead and arsenic, phosphatase test and sensory (organoleptic) test. The tests were conducted at an NABL-accredited laboratory. The presence of nutrients were given a weightage of 49 per cent as compared to the presence of contaminants (35 per cent), sensory tests (10 per cent) and packing/marking (6 per cent). All brands were found to be free from adulterants and heavy metals and therefore had an equal ranking on this criteria.
Ananda tops list: The overall top brand with 88/100 was Ananda followed by Kwality, Heritage and DMS with each scoring 87. It was followed by ‘Madhusudan’ and ‘Mother Diary’ with 86/100. Amul and Paras scored 85 and 84 points. It may be noted that these ratings show that there are only marginal differences between competing brands.
Safety: All brands were considered safe after tests for presence of adulterants: neutraliser, detergent, urea, formaldehyde and melamine. Tests were also conducted for presence of heavy metals that have a relatively high density and are toxic or poisonous at high concentrations. Milk samples were also analysed for presence of lead and arsenic. As per the requirements laid down by FSS regulation, lead should not be more than 2 ppm and arsenic not more than 0.1 ppm. All the brands cleared these tests since lead and arsenic were not found. Alkaline phosphatase (ALP) is an enzyme naturally present in all raw milk and is considered to be an indicator of proper milk pasteurisation. Complete pasteurisation will inactivate the enzyme to below levels that are detectable by conventional methods. Because the heat stability of ALP is greater than that of pathogens that may be present in the milk, enzyme serves as an indicator of product safety. However, the failure to detect ALP activity does not guarantee that the product is pathogen-free. All nine brands were found to be free of ALP. Hence, all brands were found to be safe from any adulterants and contaminants.
Microbiology: A high level of microbial count in milk may be due to not maintaining cold chain during storage and transportation (below 8 degree celsius) from plant to retailer and retailer to consumer. High level of aerobic plate count was found in Consumer Voice Tests conducted in 2011 and 2015. Food Safety Standard Regulations and Bureau of Indian Standards (BIS) states that milk should meet the specified requirement of aerobic count and coliform content at processing/plant level only. The fact is proper temperature needs to be maintained all the way to the delivery point – the cold chain must be maintained at 8 degrees celsius to avoid microbial growth. Consumers are advised to buy milk from refrigerated booths/retailing units of manufacturers. As per FSS regulations, total plate count should not be more than 30,000/gram at plant level. Plate count was below the limit in all the nine brands purchased from the retail shop. Total plate count was found highest in Paras (13,000 cfu/ml) but it was within the limit. The rating on microbiological parameters had differences with Ananda scoring full marks and Paras scoring the lowest. Consumers are advised to boil milk before consuming to destroy the bacteria.
Coliform count: Coliform bacteria is destroyed at a temperature of 46 degree celsius, which means pasteurisation can easily eliminate them up to a certain limit. The presence of coliform bacteria in pasteurised milk indicates that there were unsanitary conditions or practices after pasteurisation. All nine brands cleared this test. Pasteurisation is the process of heating a food, usually liquid, to a specific temperature for a definite time and then cooling it immediately. This process slows microbial growth in food. Unlike sterilisation, pasteurisation is not intended to kill all micro-organisms in the food. Instead, pasteurisation aims to reduce the number of viable pathogens so they are unlikely to cause diseases (assuming the pasteurised product is stored as indicated and consumed before expiry date). Pasteurisation is typically associated with milk. It is the main reason for milk’s extended shelf life.
Keep it safe at home: Consumer Voice advises not to boil milk for extended period of time. Do not leave your milk out in the open after boiling; refrigerate it immediately. Do not heat milk repeatedly. Stir the milk while boiling. Do not use microwave ovens to heat and re-heat milk.
(Prof Sri Ram Khanna is managing editor of Consumer Voice and former dean and head of Commerce, Delhi School of Economics)