MP Board · Class 12 · Biology · Microbes in Human WelfareExplain the role of lactic acid bacteria (LAB) in the preparation of curd and mention two health benefits associated with it.

Lactic acid bacteria such as Lactobacillus and other commonly used bacteria grow in milk and convert it into curd. During this process, these bacteria produce acids that coagulate and partially digest the milk proteins, specifically casein. A small amount of curd added to fresh milk as an inoculum or starter contains millions of lactic acid bacteria, which at suitable temperatures multiply and convert milk to curd, also improving its nutritional quality by increasing vitamin B12. Health benefits include: first, LAB play a very beneficial role in checking disease-causing microbes in our stomach by maintaining a healthy gut flora; second, they significantly enhance the nutritional value of milk by increasing the concentration of essential vitamins, particularly vitamin B12, which is vital for normal functioning of the brain and nervous system as well as the formation of red blood cells.