New Delhi: Preserved milk, which is designed to have an extended shelf life, may pose health risks due to a lack of essential nutrients. It is often subjected to various treatments, such as pasteurization or homogenization, which can lead to a loss of vitamins and minerals. Additionally, some preservation methods, such as ultra-high temperature treatment, can cause a significant reduction in the nutritional value of milk. Consuming preserved milk with low nutritional value can contribute to nutritional deficiencies and related health problems.


"Milk is an ideal environment for microorganisms to grow, and pasteurization is necessary to destroy disease-causing bacteria and extend the shelf life of milk. However, improper preservation or storage of milk can lead to contamination by various pathogenic bacteria, which can cause illness. Also, heat has an adverse effect on the flavour and odour of milk," said Dietician Umang Malhotra.


Concerns Related To The Consumption Of Preserved Milk:


The extended shelf life of milk, when processed, invites careful consideration of related health matters. The process has both advantages and disadvantages, impacting consumer health and waste management. Consuming preserved milk carries a risk of bacterial contamination, which can pose a threat to one's health. 


In this regard, Umang said, "The 'cooked' flavour of boiled milk is attributed to the loss of dissolved gases (CO2 and O2). When milk is heated, the heat-labile whey proteins undergo denaturation. The whey proteins are completely denatured in one hour when heated at 77.5°C, in 30 min at 80°C, and in 5 min at 90°C. Post-pasteurization contamination with spoilage bacteria can also limit the quality and shelf life of milk."


"Another concern revolves around the potential for increased oxidization due to the exposure of milk to oxygen during aseptic packaging. This could lead to the degradation of fatty acids and antioxidants, impacting the overall health benefits that milk provides," he further added.


Additionally, the use of preservatives in milk to enhance shelf stability, preserve texture, and increase palatability also poses potential health risks. According to Dietician Umang, "Some preservatives used in milk preservation, such as sodium benzoate and potassium sorbate, have been linked to health problems such as allergic reactions, asthma, and hyperactivity in children." 


Disadvantages Of Ultra Pasteurization:


Dietician Garima Goyal said that for the extended shelf life of milk, they undergo thermal processing such as ultra-high-temperature processing (UHT) and ultra pasteurization. While these techniques have revolutionized dairy markets with considerable pros, it is important to look at the disadvantages and ways to tackle them.


1. Loss of nutrients: Processes used to extend shelf life can cause milk to lose some vitamins and enzymes. Due to their high heat sensitivity, levels of vitamin C and some B vitamins may drop during preservation. The body's capacity to digest and assimilate nutrients may also be hampered by weakened milk-digesting enzymes.


2. Alteration in taste: Due to these kinds of thermal processing, certain compounds such as peptides are formed leading to an alteration of taste in milk. A bitter/oxidized or stale taste can be noticed in some milk.


3. Potential to cause allergy: The structural alterations that occur in milk proteins during these preservation methods could potentially lead to increased allergenicity, impacting individuals with lactose intolerance or milk protein allergies.


4. Hormonal changes: Studies suggest that thermal treatment for long shelf life could influence the levels of certain hormones in milk, potentially affecting their bioavailability and interaction with the human body. Though there is no concrete evidence, one may opt for minimally processed or raw milk.


Adulterants That May Be Present In Preserved Milk:


Milk adulteration is a major global concern because milk is consumed as a healthy dairy product in every part of the world. The fraudulent practise of milk adulteration is on the rise, raising concerns about the purity and quality of milk. 


In this regard, Aman J Jain, Co-Founder and CEO, Doodhvale spoke about the adulterants present in milk that can pose a serious threat to our overall health.


"From extending shelf life with toxic formalin to falsely resetting milk with caustic soda, and even cancer-causing dioxane, the health risks are dire. Altering milk's natural attributes by adding starch or oils can lead to severe consequences, especially for people with existing medical conditions. Milk that's made thicker using urea might seem richer, but it's like a fancy disguise hiding health issues like possible vomiting, and harm to kidneys, and may even appear fatal."


"Furthermore, cattle hormone injection endangers health. While oxytocin's use is banned, its persistence raises alarm. Artificial hormone consumption correlates with fluctuating blood pressure, vision impairment, memory issues, and heart disease," he added.


"Consuming preserved milk with an extended shelf life necessitates mindfulness of overall dietary variety and informed selections for a well-rounded nutrient intake. As a dietician, I stress the significance of label examination, supply rotation, and consulting with a healthcare professional to ensure adequate nutrition despite the extended shelf life of preserved milk," Richa Anand, who is the Chief Dietician at Dr. LH Hiranandani Hospital, Powai, Mumbai, concluded.