A while ago I was with a friend and she told me she is lactose intolerant. But that she does eat matured cheeses that are 18 months old. Because then the lactose is gone! Is this something right?
Answer
Dear Simon,
I think this is a very plausible story! Cheese undergoes a ripening process as you indicated. This means that the cheese actually ferments slowly. After all, so-called starter cultures are added to the milk: these are (usually) lactic acid bacteria that, over time, will give the cheese its typical taste and smell. During this fermentation, the bacteria will actually burn, or metabolize, the milk sugar present in the cheese. This causes the typical holes in some cheeses, which are created by carbon dioxide. In addition, a group of aroma components are also created. The bacteria also start to metabolize the proteins present: this also creates typical odor and taste components.
To give you an idea: even yogurt, which is fermented for a much shorter time (but at a higher temperature), in principle no longer contains lactose. So after 18 months there will certainly no longer be any lactose.
Hopefully this can reassure you!
Regards
Bruno De Meulenaer
Answered by
Prof. Dr. ir. Bruno De Meulenaer
Food Science Food Chemistry
http://www.ugent.be
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