RAW MILK - DO ITS BENEFITS OUTWEIGH THE DANGERS?
INTRODUCTION
Milk is a nutritious food that provides protein, vitamins, minerals and fatty acids. Prior to the introduction of pasteurization in the early- to mid-1900s, all milk was consumed raw in its natural, unprocessed state.
With the growing popularity of natural, local, farm-sourced foods and the perception that raw milk is healthier, its consumption is increasing. Raw milk advocates argue that it has superior health and nutritional benefits and that pasteurization eliminates these advantages.
However, government and health experts disagree and advise against consuming it. There are restrictions and regulations in many countries on sale of raw milk. In this article we shall have a look at the benefits of consuming raw milk, why pasteurization and legal provisions are world over.
What Is Raw Milk?
The milk which has not been subjected to any heat treatment like pasteurization or boiling or UHT to destroy all the pathogen bacteria is Raw milk. Primarily it is fresh milk, as obtained from the udder of a healthy milch animal, mainly cows or buffaloes but also goats, sheep, camels or yaks.
Raw Milk may be consumed directly or used to make a variety of products, including khoa, curd, cottage cheese and ice cream. In India, the co-operatives and private dairies have access to only 20% of the milk produced. Approximately, 34% of the milk is sold in the unorganized market while 46% is consumed locally.
The Pasteurization Process
Pasteurization involves heating the milk to kill bacteria, yeasts and molds. The process also increases the product’s shelf life.
The most common method of pasteurization involves heating raw milk to at least 72°C for a minimum of 15 seconds. This is called as High temperature short time (HTST) pasteurization of milk. However, traditionally a batch process was used wherein milk was heated to minimum 62 deg C for 30 min. It is called Low temp long time (LTLT). Good quality pasteurized milk can last for 2-3 weeks under refrigeration.
For a long life of milk, even Ultra-heat treatment (UHT) wherein milk is heated 138°C for at least 2 seconds. With aseptic packing, UHT milk can last up to 9 months till opened for consumption and does not require any refrigeration till opened.
Pasteurized milk is often also homogenized, a process of applying extreme pressure to disperse the fatty acids more evenly, improving appearance and taste.
- Raw milk advocates argue that it’s a complete, natural food containing more amino acids, antimicrobials, vitamins, minerals and fatty acids than pasteurized milk.
- They also claim that it’s a better choice for those with lactose intolerance, asthma, autoimmune and allergic conditions./li>
- Pasteurization was first introduced in response to an epidemic of bovine (cow) tuberculosis in the US and Europe in the early 1900s. An estimated 65,000 people died over a 25-year period from contaminated dairy. But advocates of Raw Milk argue that it is the lack of clean milk production which leads to milk contamination and hence disease.
- They claim that the heating process during pasteurization reduces the overall nutrition and health benefits of milk.
However, most of these claims are not backed up by science and are beliefs only and is argued by those favouring pasteurization
- Pasteurizing milk does not result in a significant loss of vitamins, carbohydrates, minerals or fats. Studies have found only minor losses of the water-soluble vitamins B1, B6, B9, B12 and C. Considering the already low levels of these nutrients in milk, these losses were insignificant And these minor losses are easily made up elsewhere in your diet, as these vitamins are widespread and found in many fruits, vegetables, whole grains and — in the case of vitamin B12 — animal proteins.
- Levels of the fat-soluble vitamins A, D, E and K also minimally decrease during pasteurization
- Calcium and phosphorus which are important minerals for healthy bones and metabolism are very heat stable are also not lost
- Studies have found no significant differences in the fatty acid profiles of raw and pasteurized milk, though pasteurization may increase the digestibility of fatty acids.
- No significant differences in major nutrients or fatty acids have been observed in studies conducted with raw, pasteurized and UHT-treated milk from different samples in the same dairy .
- About 80% of milk protein is casein, while the remaining 20% is whey. These may help muscle growth, improve insulin resistance and lower heart disease risk. Pasteurizing milk does not reduce casein levels, as this type of protein is heat stable.
- Some loss of whey protein may occur as they get denatured during prolonged heating but not at pasteurization temperature during a short time. Pasteurization appears to have minimal impact on its digestibility and nutritional composition.
- One study in 25 healthy people drinking either raw, pasteurized or UHT milk for a week found that the proteins from pasteurized milk had the same biological activity in the body as raw milk proteins.
- Raw milk has been associated with a reduced risk of childhood asthma, eczema and allergies. However, studies show only an associated risk reduction, not necessarily a direct correlation.
- Increased exposure to microbes within farming environments has also been associated with a reduced risk of asthma and allergies, which may account for some of these results.
- Lactose is a milk sugar. It’s digested by the enzyme lactase, which is produced in your small intestines. Some people don’t make enough lactase, leaving undigested lactose to ferment in the bowel. This causes abdominal bloating, cramps and diarrhea.Raw and pasteurized milk contain similar amounts of lactose. However, raw milk contains the lactase-producing bacteria Lactobacillus, which is destroyed during pasteurization. This should, theoretically, improve lactose digestion in raw milk drinkers.
- However, in a blind study, 16 adults with self-reported lactose intolerance drank raw, pasteurized or soy milk for three 8-day periods in randomized order, separated by 1-week washout periods. No differences were found in digestive symptoms between raw and pasteurized milk..
- Milk is rich in antimicrobials, including lactoferrin, immunoglobulin, lysozyme, lactoperoxidase, bacteriocins, oligosaccharides and xanthine oxidase. They help control harmful microbes and delay milk spoilage. Their activity is reduced when milk is refrigerated, regardless of whether it’s raw or pasteurized.
- Pasteurizing milk reduces lactoperoxidase activity by around 30%. However, other antimicrobials remain mostly unchanged.
SUMMARY: Claims that raw milk is more nutritious than pasteurized milk and a better choice for those with Lactose Intolerance, Asthma, autoimmune and Allergic conditions have shown to have little or new truth.
- Due to its neutral pH and high nutritional and water contents, milk is an ideal feeding ground for bacteria.
- Milk essentially comes from a sterile environment within the animal. From the moment the animal is milked, the potential for contamination begins with the udder, skin, feces, milking equipment, handling and storage .Contaminations are not visible to the naked eye and are often not detectable until growth is significant
- The majority — but not necessarily all — bacteria are destroyed during pasteurization. The ones that survive, mostly do so in a damaged, non-viable form.
- Studies show that raw milk contains significantly higher quantities of harmful and introduced bacteria (from contaminations from different sources)than pasteurized milk.
- Keeping milk refrigerated helps suppress bacterial growth, no matter if it’s raw or pasteurized.
- Harmful bacteria that may be present in milk include Campylobacter, Salmonella, Escherichia coli (E.coli), Staphylococcus aureus and Listeria monocytogenes. Symptoms of infection are comparable to those of other foodborne illnesses and include vomiting, diarrhea, dehydration, headaches, abdominal pain, nausea and fever .
- These bacteria can also cause serious conditions, such as hemolytic uremic syndrome, miscarriage, reactive arthritis, chronic inflammatory conditions and, rarely, death.
- Any person consuming milk contaminated with these bacteria is susceptible but the risk is higher for pregnant women, children, older adults and those with weakened immune systems.
- More recent data has shown that raw milk or cheese causes 840 times more illnesses and 45 times more hospitalizations than pasteurized dairy..
- Currently, many countries ban raw milk for human consumption, including Australia, Canada and Scotland. It’s prohibited in 20 American states, while other states restrict its sales. In addition, it cannot be sold across American state lines.
However, the number of outbreaks is increasing, especially in states that have legalized its sale
SUMMARY Raw milk can contain harmful bacteria that may lead to serious illness, particularly in pregnant women, children, older adults, and immunocompromised people. Infections are more frequent and severe than those caused by pasteurized sources.
The Bottom Line
Raw and pasteurized milk are comparable in their nutrient contents. While raw milk is more natural and may contain more antimicrobials, its many health claims aren't evidence-based and don’t outweigh potential risks like severe infections caused by harmful bacteria, such as Salmonella, E. coli and Listeria.
