Scientists make milk like beer. Will it make milk taste better?

People who pay attention to health know that drinking milk regularly is a good thing. It not only supplements calcium, but also provides the body with high-quality protein. But some people cannot drink milk, either because they are intolerant or allergic, which is a headache. Is there a way to make milk more nutritious and meet the drinking needs of more people? You won't believe it, but this method has been developed. It is artificial milk made using 3D printing and fermentation technology. Today, let's take a look at what it looks like.

Making milk from yeast

Milking a cow drop by drop is a way that has been passed down for several years, but it is being changed by new technology. So how do we get rid of the shackles of raising cows and get fresh milk directly? Milk made with simple chemical reagents is not milk, and it is not nutritious or safe. If you want to know how to do it, you must first understand milk.

The so-called milk is animal breast milk, a white or slightly yellow liquid secreted by the mammary glands of female mammals, 87% of which is water, and the rest includes nutrients such as protein, fat, carbohydrates, vitamins and minerals. What we usually call milk is basically cow's milk.

The key to simulating milk is to create a liquid with the same ingredients as milk. Scientists have tried many methods, and finally focused their attention on an ancient method, which is yeast fermentation. To put it simply, it is to use yeast to create a liquid similar to the nutrients in milk. Does it sound incredible? In fact, this is a collection of ancient human wisdom and the application of new technologies.

The picture comes from Tuchong.com

There is a reason why yeast fermentation was chosen. Friends who are familiar with yeast know that it is a type of eukaryotic organism, mainly used for brewing production. It is one of the important fermentation bacteria in our daily lives, such as soy sauce, wine, vinegar, bread and other foods. It is used to make milk, not only because it is easy to cultivate, but more importantly, its genes are already very clear, and it is also the most commonly used receptor cell in gene cloning experiments. We can transfer genes from other organisms to yeast, and then obtain the desired proteins and other components through gene expression. A scientific research team has produced the anti-cancer drug vinblastine by genetically modifying yeast.

3D printing has new uses

Let's talk about the manufacturing process of artificial milk. First, a yeast strain called Buttercup was found, and the cow DNA sequence that had been obtained was printed out using 3D printing technology, and then these gene sequences were implanted into these yeast strains. The second step is to add these yeasts to plant sugars such as corn syrup for fermentation, and then obtain casein and whey protein, which are the main protein components in milk. The third step is to separate these proteins from the yeast and residual sugar, and then filter, purify, and dry them to finally make pure protein powder. The last step is to mix the protein powder with water, vitamins, minerals, vegetable fats and sugars according to the proportions in natural milk, and a cup of fresh artificial milk is born. It sounds simple, but the technological content here is indeed high. For example, the purification of protein is more time-consuming.

Some people may ask, will there be a big difference between the milk made in the laboratory and natural milk? In fact, the difference in taste is not that big, because taste is mainly related to ingredients. Since the main ingredients are the same, the taste is naturally similar. However, artificial milk should lack some flavor substances naturally present in feed, and there will definitely be some differences if you taste it carefully. From the perspective of nutritional ingredients, the main nutrients in natural milk are all here, and some desired ingredients are added, such as human milk oligosaccharides that are beneficial to health. Of course, some unwanted ingredients can also be deleted, such as lactose that causes lactose intolerance.

As for the difference between the two, artificial milk has a longer shelf life, while natural milk has richer ingredients. Of course, the biggest difference at this stage is that artificial milk is too expensive, but I believe it will definitely be cheaper in the future, so those who want to try it should be patient.

However, many people have expressed concerns about this matter, thinking that although reducing the number of cattle and sheep does reduce a certain amount of greenhouse gas emissions, it also has a significant impact on traditional agriculture and animal husbandry. Personally, I think technology always has two sides, so please wait and see.

This article is a work supported by Science Popularization China Starry Sky Project

Author: Zhang Yu

Reviewer: Chen Ran (Deputy Research Librarian (Science Communication)/Senior Engineer, COFCO Nutrition and Health Research Institute)

Produced by: China Association for Science and Technology Department of Science Popularization

Producer: China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.