Some startup companies have claimed that they can commercially and sustainably produce an animal-free “milk.” As a dairy chemist, I have to caution that unless we reimagine milk as a simple mixture of a couple of basic components with added color, these claims are not likely to be realized anytime soon.
Various terminologies are being used to describe these “novel” processes. One popular term is precision fermentation, which is the same as microbial fermentation used more than 30 years ago to produce recombinant calf rennet. To make rennet via microbial fermentation, the gene from the calf was inserted into an industrial strain (yeast or bacteria) that was then grown in a fermenter. The rennet protein was then isolated and purified.