Lactose and Fermentation

If there is a nation whose understanding of food, nutrition, and digestion is even worse than Britain's, it is India. Although the British influence could be showing it's hand there too, I suppose.

Case in point, "Fermented delicacies" by Vibha Varshney on the DowntoEarth.org website.

Other fermented foods also have medicinal uses. Dahi is said to check diarrhoea. Nutritionists say it regenerates damaged gut epithelium. “Fermentation converts lactose into glucose and galactose, which is easily digestible by even the lactose- intolerant. Also, milk does not have essential vitamins like B₁, which bacteria in the curd provide,” says P R Sinha, National Dairy Research Institute, Karnal.

First, dahi.

Strained yoghurt, yoghurt cheese, labneh (Arabic لبنة), or Greek yoghurt is yoghurt which has been strained in a cloth or paper bag or filter, traditionally made of muslin, to remove the whey, giving a consistency between that of yoghurt and cheese, while preserving yoghurt's distinctive sour taste. Like many yoghurts, strained yoghurt is often made from milk which has been enriched by boiling off some of the water content, or by adding extra butterfat and powdered milk.

Now. It's digestion that splits the compound sugar, lactose, into the simple sugars glucose and galactose.

Fermentation turns the lactose into lactic acid, which accounts for the sour taste of most unprocessed commercial yogurts. Fermentation is produced by various bacteria and yeasts, which produce the lactic acid as a waste product. It is the lowered lactose content that makes yogurts and other fermented foods well tolerated by the lactose intolerant.

Could you say that the bacteria split the lactose into glucose and galactose and then produce the lactic acid as a secondary step? This is not the way it's usually described. In fact, the bacteria in your colon are normally considered to be either lactose fermenters or lactose digesters. The fermenting bacteria are the ones that create the gas that so plagues those of us who eat lactose-containing products.

And wait a second. Milk doesn't have vitamin B₁? The U.S. National Dairy Council begs to differ.

Significant quantities of this vitamin are found in milk with an average of 0.04 mg per 100g. AS the RDA for thiamin [vitamin B₁] varies between 1.0 and 1.5 mg for the adults, two glasses of milk per day would supply about 12 to 19 percent.

Nope, I'd say this is a confusing mistake. I don't know whether the man from the National Dairy Research Institute is to blame or, more likely, whether the reporter garbled the account. Either way, don't take it as read.