Oh, it works more or less, but it doesn't taste the same as cake yeast to me.
Ah, gotcha... when you said it was a dud, I thought it just wasn't working at all for you.
Yup, that's the way I mix dry yeast, but it just doesn't taste the same in old bread recipes. Very strange that in this very small town I can find quite good rye bread...not as good as home made though. I have to order rye flour from King Author flour co.
Yeah, I feel you... fresh yeast does impart a slightly different flavor. I also get my rye flour from King Arthur. I have only ever found a few bakeries that make a good rye loaf though... and I no longer live near any of them

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I saw that you were looking for fresh yeast to make a sourdough starter... if the unique flavor means that much to you, have you considered the following options:
1) Make your own starter from wild yeast - there are many strains of wild yeast that exist naturally and can be found in high concentrations on fruit peels. Often, the strains of yeast associated with certain fruits produce metabolic byproducts that smell like the fruit they are associated with. My mother is microbiologist and had a culture collection of yeasts she had isolated from various fruits back in the day, including one that smelled exactly like fresh blueberry pie! I know a lot of old school bakers make starters by fermenting fruit peels with flour, then discarding the peels before using the starter for baking (a classic rustic baking technique). This also gives you the opportunity to experiment with different fruits and find the unique flavor profile you like.
Example link - she grinds up the whole apple... but you can also just peel the apple and throw the peel into the flour mix... the peel can then be removed and will prevent unwanted addition of crushed fruit to a recipe. I have done similar experiments with various fruits in the past and the results can be quite nice!
2) Are you aware of Carl's Friends? I have never tried it, but a friend who also bakes once told me about it. Apparently it's an exchange, of sorts, that passes around a sourdough starter culture that has been in continuous use since the mid-1800's. I don't know if they still do it or not, but supposedly they distributed it for free to anyone who sent a self-addressed, stamped, envelope. It is sent in a semi-dry form that you have to restart and culture though. I never got a chance to try it, but the results were supposedly pretty good.
Best of luck!