There has been some speculation over the efficacy of instant bakers yeast in producing ethanol elsewhere on these pages. So I’m reporting my results here for what its worth.
Mixed the following:
10L clarified “sour mash”, i.e. that what was left in the kettle from a previous distillation without the nasty bits that gravitated out.
2 L bottled water.
2.5 kg cane sugar.
Pinch of Nutrifeed (horticultural/hydroponic salts)
Pinch of MgSO4
Vit B tablet
Teaspoon of NaHCO3 as buffer
10g (one packet) of instant yeast.
I’ve measured the SG using a 10ml A grade pipette and a jewellery scale, and found the fresh mix to be 1.082 kg/L.
Two weeks hence, the SG measures 1.022 kg/L. The decrease in density is presumably due to the conversion of the sugar into C02 and ethanol via separate metabolic pathways. According to this nifty calculator, I can expect around 7.9% alcohol based on the SG measurements.
I’ll let the mash sit for another day or three until the fizzing peters out. Once distilled, I’ll update this thread with some more numbers to see if the yield was as predicted.