Hey, sorry I've been away from my computer for a few days and have missed several questions. I'll probably be like this until holidays are past.
Cathe,
One thing I did that seemed to mellow out the Kefir REALLY quickly, was put a tight mesh on the lid of the jar and screw a metal band on it (canning jar). Letting it 'air out' as it ferments keeps it from developing that 'sourdough bread' smell.
I also set the jar (mesh lidded) in the oven with light on for about an hour and (to make long story short) it 'off gassed' even quicker and or developed a really super mellow flavor.
Bacterias like warmer temperatures, approaching body temps. Yeasts do fine and prefer cooler temps. So, fermenting at room temp will develop more yeasts (and ergo that 'sour' smell).
Bacterias like you get for making yogurt and used in the warmed milk, will prefer warmer summer day ferments or sitting near or in a warm spot. So try sitting your jar in the oven with light on. You could leave the door ajar too. Just don't let it get TOO hot.
I also noticed a nice flavor after fermenting the grains in some coconut milk (canned) once or twice a month.
Just some hopefully helpful tips for anyone 'playing around' with the ferment time and flavors!
P.S. Now I always ferment my Kefir with the 'aerated' mesh lid.

Also, if I've missed any PMs or Emails about grains, please PM or Email me again before Monday. I should have enough to ship out some more grains, now that Thanksgiving is behind me ....
Another Note: I appoligize to all, I've been pulled in twenty directions the last few weeks and it's gonna get worse. I have 6 birthdays in Dec, 4 in January, and 3 in Feb...on top of holiday shopping and my brothers are coming to visit..so trying to get house ready...I'll be very sporatic and seem very disjointed in my posts! I do love you all and will try to help answer some of the questions as I can!

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