What Are Kefir Grains ?
Kefir grains are the natural mother culture of both milk and water kefir. They are not actual grains as in rice, millet or other such grains. Rather, they look kind of granular, hence their name.
These grains are naturally occurring in nature and they cannot be made. Only starter cultures in powder form are made in the laboratory.
Both milk and water grains composed of a number of bacteria and yeasts living together in a symbiosis relationship. Each batch of kefir grains may differ from another in the number of bacteria and yeasts strains. Kefir grains feed on the food derived from the milk or sugar-water in which they are placed in. This process of them eating and feeding will cause byproducts such as enzymes, lactic acid, carbon dioxide and a little ethanol (alcohol).
Kefir grains digest the lactose in milk which is why kefir is usually suitable even for those who are lactose intolerant. When all the food present in milk or sugary-water is consumed, there is no more food left and the beverage is considered done.
Long Live Kefir Grains !
As the grains feed on food, they will grow and reproduce. This means to say that with proper care, live grains will last forever. So, if your grains are healthy, they will serve you and your descendants for years to come!
Grains Be Contaminated ?
You bet they can! The good news is that this very seldom happens. The bacteria and yeasts that makes up live kefir grains are strong and resilient. They usually overcome pathogenic bacteria, which is why candida sufferers use kefir as part of their regiment to combat candida.
However, if you are unable to care for the grains properly, you may face issues such as grain contamination or your grains start to ‘die-off’ (due to starvation!), You will know your grains are contaminated if you see colors that is not native to the grains present such as yellow, orange, blue, green or gray.
The complexity of the milk kefir grain is a mixture of protein, amino acids, lipids [fats] and soluble-polysaccharides.
While milk kefir has been compared to yogurt (though it has superior properties compared to yoghurt), Kefir’s microflora is much more complex. The exact composition of microorganisms that form the grains usually varies slightly, depending on the media where they are cultured, and so water and milk kefir differ in some microorganisms that may specifically grow on milk and not fruit, and the other way around. Also, depending on the fruits used to culture Water Kefir, we may be adding new friendly yeast and bacteria to our grains.
The Complex Microflora
Milk Kefir Grains Composition
Below is a list of the bacteria and yeast strain that is commonly (though not exactly the same in every batch) found in a batch of milk grains.
Species : Lactobacilli (Lb)
Strains : Lb. acidophilus
Lb. casei subsp. casei
Lb. casei subsp. rhamnosus
Lb. paracasei subsp. Paracasei
Lb. delbrueckii subsp. bulgaricus
Lb. delbrueckii subsp. Lactis
Lb. kefiranofaciens subsp. kefirgranum
Lb. kefiranofaciens subsp. kefiranofaciens
Species : Streptococci (S)
Strains : S. thermophiles
Species : Lactococci (Lc)
Strains : Lc. lactis subsp.
Lc. lactis subsp. lactis biovar. diacetylactis
Lc. lactis subsp. Cremoris
Species : Leuconostoc (Leuc)
Strains : Leuc. mesenteroides subsp. cremoris
Leuc. mesenteroides subsp. mesenteroides
Species : Enterococci (Ent)
Strains : Ent. Durans
Strains : Dekkera anomala / Brettanomyces anomalus
Kluyveromyces marxianus / Candida kefyr
Pichia fermentans / C. firmetaria
Yarrowia lipolytica / C. lipolytica
Debaryomyces hansenii / C. famata
Deb. [Schwanniomyces] occidentalis
Issatchenkia orientalis / C. krusei
Galactomyces geotrichum / Geotrichum candidum
Kluyveromyces lactis var. lactis
Sacc. subsp. torulopsis holmii
Sacc. turicensis sp. nov
Strains : A. aceti
Water kefir grains contain bacteria from the lactobacilli species, streptococci and leuconostoc and fewer strains of yeasts compared to milk kefir grains.
Live Grains VS Starter Culture Packs
So, is it better to use live grains or starter culture?
Advantages of using live grains
Advantages of using starter culture packs
1. Health Properties – live grains contain many more strains and species of probiotics and need not be replenished. In fact, they reproduce.
2. Cost – starter culture packs are much costlier and needs to be replenished after a few rounds.
1. You know what exactly are the strains of culture used (for those who wants to avoid certain strains or yeasts)
2. Convenient – not much care needed