Sourdough starter with whey?

Hi all,

It's my first post here, but I've been reading and enjoying these pages for quite some time. I'm looking for some advice.

A couple of months ago, I picked up a package of what I guessed was a sourdough starter mix in a fairly good food/baking shop in Tokyo. I already had a healthy sourdough culture in my fridge, but I was just curious and it wasn't expensive or heavy, so I just added it to my major purchases of flours, vital gluten, dried fruits, grains, etc. It's a 100g package (say, 3oz or so) but has no included information on how to use it. I searched the web-site of the company that produced it [Tomizawa] for more info and they were completely silent about its use, as well. I suppose it must be explained in some Japanese baking books that are WAY beyond my meagre Japanese reading skills.

On the label it's called "whole sour" and then, in parentheses, it says "sour seed" in Kanji (Chinese) characters. The label says it contains rye flour, wheat flour and whey (powder) but there's no mention of proportions. The recommended 'Use-by' date is approaching...

I've been baking 'New York Style' light rye bread successfully for years (without sourdough starter, mostly from bread machine recipes) but the main reason I started my first sourdough culture (with pineapple juice and rye flour) was eventually to bake real 'Bauernbrot' rye bread at home. (I'm not quite skilled enough to do that yet.)

I'm wondering what to do with this stuff. Does it need special care and feeding? Does it need milk instead of water or fruit juice? Is there really such a thing as a 'rye starter' as opposed to a regular 'wild yeast' starter? I have a respectable bread-baking library here at home, but my problems are more of the 'information-overload' kind...too much advice, quite a lot of it conflicting, and almost none of it relevant to the brutal Japanese climate I'm living in! (We're actually having a beautiful Spring this year--almost like Autumn weather--warm days and cool nights. I shouldn't complain...)

I apologize if this sounds like a 'rant' or if there are too many questions, but I'd appreciate any advice about this starter mix. I also want to thank Floyd and all the contributors to this great bakers' resource!

Best to all,

copyu