After some help from others on this forum, I've been enjoying some really good kefir. Lately, I've been "slow brewing" it: I put the kefir grains in a gallon-size glass jar, add whole milk, and let it warm up for two-three hours -- enough to warm up to maybe around 60° or so, but not really enough to reach room temperature. Then I put the jar in the fridge and wait a week, maybe stirring a time or two along the way. For the first 5-6 days, nothing much seems to happen ... but then it begins to thicken, and winds up quite thick indeed. But -- and here is the key for me -- though it is a bit tangy and very frothy and thick, it is not sharp or sour. Like drinking a milk shake -- utterly delicious! And of course, I work on drinking up that gallon while the next one is brewing.