Is Pasteurized and UHT treated milk hygienically safe for consumption?


Is Pasteurized and UHT treated milk hygienically safe for consumption?

Milk is a nutrient enriched liquid that is primarily produced by the mammary glands of the mammals to feed the human population. Human infant’s breastfed before they are able to digest solid food. Early lactation fortifies the immune system having antibodies and reduces the risk of many diseases, beside this, it comprises many vital nutrients including lactose and protein. Interspecies feeding of milk is common particularly among humans, many of whom consume the milk of other mammals.

Milk is considered as the world’s most complete food having 84 % water, 4% fat, 4.6% lactose and 3 % protein. The composition may vary according to the animal type, breed and physical characteristics. Milk is naturally hygienic and safe for consumption but contaminated from various sources air, feed, soil, milking equipment, cow’s udders, feces, flies and manure. Milk is an intricate biological fluid and highly vulnerable to bacterial contamination, therefore, it serves as an excellent growth medium for the majority of microorganisms1.

The Food industry faces great economic losses by bacterial spoilage due to a large number of microorganisms in raw milk and post-pasteurization contamination, pasteurization itself can’t guarantee the removal of microorganisms. Pasteurized milk has a comparatively short shelf life where UHT (Ultra-high temperature processing) milk can be stored for three to six months at ambient temperature as it is heated to 135-140EC for a few seconds2.

Total viable bacterial count is one of the acceptance criteria for checking quality and safety of dairy products. Research indicated that organism such as Coliform and E. coli is a burning health issue as they can bring out a serious hamper to human health, especially to children as they are vital consumers of milk. In several countries, have total viable bacterial count in pasteurized milk ranges from 5×103 – 5×105 CFU m LG13.

In a novel research published in ‘American Journal of Food Technologyto access the microbial status of processed and raw milk samples collected from different local small farms and markets in Bangladesh. The researchers found that available commercial pasteurized and UHT milk in Bangladesh was contaminated by pathogenic bacteria which are a threat to public health. These virulence factors in milk is very alarming for the milk industry of Bangladesh needs core attention of the regulatory authorities to strictly implement the hygiene practice for the milk processing industry4.


  1. Islam, M.A., S. Roy, A. Nabi, S. Solaiman and M. Rahman et al., 2018. Microbiological quality assessment of milk at different stages of the dairy value chain in a developing country setting. Int. J. Food Microbiol., 278: 11-19.
  2. Meunier-Goddik, L. and S. Sandra 2011. Liquid Milk Products: Pasteurized Milk. Encyclopedia of Dairy Sciences. 2nd Edn., Elsevier, Accedmic press, Cambridge, Massachusetts, United States pp: 274-279.
  3.  Zhang, Y., P.Y. Hong, M.W. LeChevallier, W.T. Liu, 2015. Phenotypic and phylogenetic identification of coliform bacteria obtained using 12 coliform methods approved by the US environmental protection agency. Appl. Environ. Microbiol., 81: 6012-6023.
  4. Muzahidul Islam, Sadia Afrin, Firoz Ahmed, Barun Kanti Saha and Md. Nur Hossain, 2021. Microbiological Quality Assessment of Raw and Commercial Milk Available in the Local Market and its Acceptability. American Journal of Food Technology, 16: 1-8.