pH

  The Power of Hydrogen, or pH, is a measure of how acidic (<7) or basic (>7) a solution is on a logarithmic scale. It’s the most fundamental analysis in all of winemaking informing us of microbial inhibition, chemical speciation, and tartrate stability.  At wine pH (~pH 3-4), there are no dangerous pathogens to human life, and this has largely shaped the traditions and legislature around winemaking. Since there is no risk of food born illness, winemakers have far more leeway with winery sanitation than with other food products. Nevertheless, pH helps winemakers understand the proclivity of wine towards spoilage, thus giving them a framework for sanitary demand. Rather than thinking of sanitation as an absolute, we can address its demand as a spectrum relevant to the style of wine one hopes to achieve. The limits for cleaning and sanitation are well-defined: Clean: removal of soil and 90% reduction of colony forming units. Disinfection: a reduction of 99.9% of colony forming unit