Waterkefir is a refreshing light alcoholic (0.3-2.0%) sparkling drink.
Waterkefir is made by adding 6 teaspoons of waterkefir grains to 2 l of water, 100-150 gram of sugar and 2 figs. The mixture is left to ferment at room temperature for 2-3 days and flavoured with, for example, lemon juice. It should be drunk cold.
Waterkefir, also known as tibi, probably originates from Mexico and is not related to the more common normal (milk-)kefir.
In the early 20 th century waterkefir became known in Europe . It is now mainly used in Belgium, Switzerland and Italy, but can be obtained in other countries.
Waterkefir grains have a structure resembling sugar grains and consist of a mixture of micro-organisms. The grains contain both yeasts and lactic acid bacteria, but the (limited) literature is very contradictory on the exact composition of the grains. Probably the composition is not constant and varies with the origin of the grains.
Waterkefir grains (source)
The following yeasts and bacteria have been isolated :
Yeasts : several Candida, Brettanomyces, Saccharomyces, Cryptococcus and Rhodotorula species.
Bacteria : Lactobacillus hilgardii, Lactobacillus casei and other Lactobacillus species, several Bacillus species, Brevibacterium vermiforme and Lactococcus lactis .
The yeasts are responsible for the alcohol, carbon dioxide and flavour; the bacteria for the flavour and the acids.
The sugar-like structure is caused by dextrans. Dextrans are polysaccharides, related to starch, that are made by the micro-organisms as storage foods from the sugar in the liquid. Which species are responsible for the dextrans is not yet known.
The figs in the recipe are necessary for a good product, as it has been shown that figs contain an (unknown) growth factor for the micro-organisms. Instead of figs, fig pulp can be used. Raisins and cactus leaves (Mexico) can be used, but give a slightly different product as they do not seem to have the growth factor.
Many different health promoting effects are attributed to waterkefir and tibi, but these have not properly been studied and no scientific literature is available to support any of the claims.