Hi guys, I am trying to get my backyard yeast to give a try to a lambic beer. I put some plum and peach rinds in a pint of a 1030 hopped wort a week ago, after 48 hs it has started to show activity so I put it on a stir plate for a day. After that it started working hard forming a nice krausen. Now it is still fermenting , a bit slower though but it has a rate of 3 bubbles/min. It smells very good, no funky odor at all, something fruity(there are pieces of peachs though) maybe a bready aroma. I was wondering what kind of microbes might be there, it has a mild greeny colored layer atop the wort, and another whitish layer as well. I am planning on adding a quart of 1030 unhopped wort to enhance cell count and then step it 1.5 gal, but Iam not very sure what I am going to end up with.I would like to brew a 1070 lambic beer, do you think this planned starter could work properly for this proposal? Here some photos:
I have done an award winning sour with this method. I would step it up once more, maybe twice to give the yeast and good bacteria time to grow strong, raise the alcohol, and lower the pH to kill off any of the bad stuff. At that point try to wash the yeast with sterile water and get it to just yeast (remove the hops and trub from your starters. Do a standard starter with no hops, no stir plate, no shaking. Let it ferment and drop clear, then draw a sample taste and gravity. This will give you a better idea of what you have. If it is super fruity, and mildly acidic, great. If it smells foul, don't touch it.
I am a bit worried about some pathogens (eg. E. Coli) , I have read some bacteria can live even at a pH below 3.5. Is it a bad idea to add ethyl alcohol?
There shouldn't be anything harmful that would make it through those cylces. Step up your current starter, then again. Crash, decant, wash, new starter. Then taste if it smells good. I wouldn't add alcohol to the starters as the concentration could kill off good bacteria or yeast as well. By going through the cycles of stepping up you are naturally selecting yeast/bacteria that will thrive in an alcoholic and low pH system.
be sure there are no fruit flys or other flying beasts. those bastards will do a fine job making vinegar. good luck. you are more adventurous than I. Cheers.
