Traditionally in a region of the Caucasus Mountains, kefir was prepared with raw, full-cream goat or cow's milk. Fresh milk with the addition of kefir grains stored in a goatskin leather bag was left for 24 hours to ferment at room temperature. This initiated the fermentation process. Separation of the grains was achieved by forcing the contents to a corner of the leather bag by hand, where most of the grains were retained. The liquid-kefir was separated from most of the grains by pouring the contents into a container. This kefir had a moderate sour taste, creamy in texture and consistency with an alcohol content of around .5% by volume. During cold conditions, the goatskin bag was kept in the sun during sunny cold days, or hung near a fireplace. Apparently, it was a custom to hang the bag near a door way, where by anyone passing by would shake the leather bag. This was possibly performed as a religious ritual, with a beneficial consequence by assisting the culture-process.
Maturation Larger quantity of liquid-kefir was stored in sealed wooden barrels of clay crocks, where secondary fermentation preserved the beverage as the beneficial kefir ripened over some days. Ripened kefir was enjoyed over extensive periods as it matured, for a powerful anti-oxidant produced in kefir through fermentation, preserved the nutritious beverage without the need for refrigeration. As portions of liquid kefir was removed from the barrel or crock for immediate consumption, more freshly strained kefir of the day, was added to replenish the vessel.
To elaborate further. A mixture of freshly strained kefir of the day, sometimes with the addition of fresh milk including the crushed root of another anti-oxidant rich ingredient, Snow Rose [Rhododendron caucasicum] was stored in wooden barrels, or clay crocks. The sealable vessel was plugged airtight. Over some days, this produced a foaming effervescent beverage, with an alcohol content of around 2% and up to 3% v/v. The kefir had exceptional good keeping quality, with a substantial increase in some B group vitamins. Folic acid [Vit. B9] increases by more than 100% at 2-days storage. Research shows that at, cholesterol and milk sugar content reduce at the end of the initial fermentation with the grains, with less reduction of these components during maturation in a sealed container. This provides a more nutritious beverage with a better health-promoting profile compared to the freshly strained liquid-kefir, including the non-fermented fresh milk.
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