I beg to differ on the "Dunder is the yeast-rich foam leftovers from one batch of rum that is used to start the yeast culture of a second batch" or the yeast cake etc etc. there are a multitude of recipes that use "dunder" UJSSM for the most common example and it is the skanky shite thats left in the boiler after a strippin or first run of a wash thats added back to the next wash, ie sour mash ... More @Wikipedia
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