Nearly a week after our kefir arrived, I have some new thoughts (and a bit of research) to share about the fermented food.  Mostly, I was curious about how kefir differs from the fermented milk product I'm most familiar with --- yogurt.

Our kefir sulked for a day, then gelled up its first cup of whole milk (from the grocery store) in 48 hours.  After that, it's been gelling up a cup every day, despite our cold trailer (down to 40 or so at night).  That experience alone is a major selling point for kefir over yogurt for the low-tech --- kefir bacteria and fungi will keep working anywhere between 39 and 86 degrees Fahrenheit, while yogurt need a special warming container to hold the critters at 110 degrees.

How about flavor?  To my untrained taste buds, kefir and yogurt taste identical.  Yes, kefir is runnier than store-bought yogurt, but when I went through a phase of making yogurt at home, it ended up at about the same consistency as this homemade kefir, so no big difference there.  Unfortunately, Mark's not a fan of the kefir/yogurt taste, so I have to doctor his dose with cocoa and honey.  My favorite way to eat kefir is the same as my favorite way of eating yogurt --- swirling in some unsweetened, homemade applesauce (see below).

While researching the differences between kefir and yogurt, I discovered one tidbit that should help even those of you who aren't likely to make your own fermented milk products.  The beneficial bacteria in both foods are found primarily in the whey (the clear, runny part).  So, if you buy Greek yogurt (what we've been buying), you get a higher protein content but less of the good stuff because the whey has been strained off.  Ditto if you pour off the whey that tends to separate out of plain store-bought yogurt --- stir it back in instead for best health benefits.

So, what are the beneficial critters in kefir and yogurt?  Yogurt only contains bacteria, and usually you get just one or two strains of Acidophilus sp. and Streptococcus sp. in your yogurt.  Kefir is a symbiotic arrangement between bacteria (up to thirty species including Lactobacillus spp., Enterococcus durans, Lactococcus lactis, Leuconostoc spp., Acetobacter spp., and Streptococcus spp.) and fungi.  The latter are perhaps the real selling point of kefir over yogurt since these yeasts don't pass through your gut, instead colonizing your intestinal linings where they help you resist invasions of E. coli and intestinal parasites.  So eating kefir can cause long-term positive effects in your bowels, in contrast to yogurt, which will only influence your digestion for about 24 hours after ingestion.

Which brings me to another point --- how long to culture kefir.  I've been culturing just until the milk starts to goop up, but further reading suggests I might get more benefit out of culturing the kefir longer.  Over time, the microflora of the milk changes, with the dominant critters giving way to others in a steady progression of Lactococci, then Lactobacilli, next Leuconostoc, then yeasts, and finally Acetobacter.  I need to do more reading on the benefits of each kind of microorganism and on how to tell visually when the kefir has reached each stage, but from my first round of research, it sounds like reaching the yeast stage would be most beneficial.

More on my experiments in later posts, but I'll close with a few more tidbits I stumbled across during my research.  Did you know that you can use the whey from kefir to jump-start lactofermented vegetables, reducing or eliminating the need to add salt?  And that kefir grains grow 5 to 10% daily, so I should have a starter culture to share with one lucky family member within a month.  (Put in your orders today!)

Phew, that's a long post, but I'm always excited to learn more when we add new livestock to the farm.