Food (hygiene) rules are there even if we don’t know them. ex a basic rule is that a group of food poisoning organisms can not grow below pH 4. , , , , When we are making wine we don’t want to get sick or kill someone with anaerobic botulism which will grow above pH 4. Techies and the folks writing winemaker columns ignore the rule since grapes are lower than pH 4 and other rules as 8% alcohol (on the finished wine). If I am making shelf stable 64 ounce bottles of 100% fruit juice punch or juice pouches I have to know which safety rules are critical (HACCP) All in all the wine rules are extremely complicated since they act in concert , , , , pH works with anaerobic conditions (no oxygen) which works with residual CO2 (redox potential) which works with osmotic pressure (dissolved solids) which works in concert with increasing alcohol from 8% to 11% to 14% to 20% which works in concert with SO2 which works in concert with types of metabolizable food (residual sugar) which works with ppm phenolic compounds (tannin),. . . . and there are probably more which only a university professor knows. This forum could be shut down for lack of use if the rules had only one critical factor, , or we all started with a perfect red grape must that was sprayed with sulfur compounds such that it produced 25 years of shelf life.