Cameron Begg wrote "He mentioned "Candida" as the yeast genus responsible. Any ideas George?" I have heard of Candida yeast, and have heard of some species of them being associated with problems like chronic fatigue syndrome. The skepticism I mentioned about yeast being involved with chile mash fermentation was primarily about Saccaromyces sp. which convert carbohydrates to alcohol and carbon dioxide. Candida sp. could very produce lactic acid or acetic acid under these conditions. Need to look these up to confirm. The species that springs to mind is Candida utilis, but I am not sure of its properties. George Nelson 70431.3065@compuserve.com