Fermented Milks | Health Effects of Fermented Milks

Abstract

In many parts of the world, from the distant past, fermented milks have been consumed as valuable food sources. They have also been recognized as foods that have health effects. The modern-day interest in the health effects of fermented milks is said to have been stimulated by the theory of longevity formulated by Metchnikoff in the early twentieth century. This hypothesis proposed that people consuming fermented milk regularly live longer, as lactic acid bacteria (LAB) ingested in the fermented milk colonize the intestine and inhibit putrefaction caused by harmful bacteria, thus slowing the ageing process. The studies that followed Metchnikoff’s claims proved that the LAB from yogurt does not colonize the intestinal tract. Based on the assumption that LAB of the intestinal origin may colonize the host’s intestines, many trials have been done, beginning with Lb. acidophilus or bifidobacteria, as advocated in the 1920s. These days, the development of fermented milk products is aimed at the ability to colonize or to enhance health functions. The microorganisms from such fermented milks are generally referred to as probiotics. Several principal health effects so far studied over the world are summarized. They are usually divided into two groups. One group refers to ‘nutritional function’, which is expressed as the function of supplying more nutrition efficiently. The other is ‘physiological function’, which includes the prophylactic and therapeutic functions beyond nutritional effects.