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For Harvest Essential Analyses The 10 most important laboratory analyses and contingency tests By Jean L. Jacobson Alcohol analysis (seen above at at Enartis Vinquiry) is used to calculate potential alcohol content as well as actual content post-fermentation. For decades winemakers have relied on these test results in addition to physical and organoleptic evaluation of the fruit, juice and must to determine when to harvest and proceed into primary and secondary fermentation. With today's technological and enologi- cal advancements, winemakers have the tools and information to make excellent winemaking decisions and the ability to consistently produce quality wines. Wine- makers know their "must-have" analysis plan prior to harvest and have contingency plans. What are the must-have analyses, and why have they chosen them from the plethora of analyses available? pH, ammonia (NH3 H Commercial lab analyses Let's look at what ETS Laboratories of St. Helena, Calif., and Enartis Vinquiry Laboratories of Windsor, Calif., consider 26 WINES & VINES OCTOBER 2012 istorically, basic grape and juice analyses prac- ticed by most wineries or requested from commercial laboratories included Brix, titratable acidity (TA), ) and malic acid. their basic or core panel juice analyses. Both laboratories include Brix, TA, pH, malic acid, NH3 and alpha amino nitro- ing simple nitrogen to the yeast for the initial phase of fermentation and NOPA to measure the more complex amino nitrogen used after the initial start of fermentation. NOPA results do not contain the amino acid Proline, which is not utilized by Saccharomyces yeast and can contribute more than 50% of the amino acid content from an analysis that measures total amino acids, leading to false reported levels of nitrogen available to the yeast. The NH3 independent of each other, NH3 provid- results plus the liter, or parts per million (ppm), equal the yeast assimilable nitrogen or yeast available nitrogen (YAN.) NOPA results are reported as mg N2 ETS Laboratories also includes tartaric acid, potassium and glucose + fructose in its basic juice panel. The addition of tar- per gen (or NOPA), which measures nitrogen via the OPA (orthophthaldialdehyde) method using spectrophotometry. They include both nitrogen methods since NH3 and alpha amino nitrogen are taric acid and potassium rounds out your acid profile, which is helpful for possible acid adjustments, and the glucose + fruc- tose supplies the information to calculate potential alcohol. You can opt for their enhanced juice panel, which contains the analyses from their basic juice panel plus the addition of the Scorpion VA-Producer Juice Panel, which gives you genetic detection of organisms that contribute to volatile acidity (VA) such as Acetobacter and Gluconobacter and the yeasts Hanse- niaspora and Kloeckera. Enartis Vinquiry offers a second juice panel containing the analyses from their core juice panel with additional analysis for potassium and an organic acid profile (includes the major wine acids: malic, tartaric, lactic and acetic), thus provid- ing information needed for possible acid adjustments and more. The lactic acid data can tell you if malolactic fermenta- tion has begun (posing a possible co- fermentation scenario), and the acetic acid data is a marker for spoilage. The final analysis addition to the above panel is a rapid semi-quantitative Botrytis risk as- sessment. Botrytis cinerea, a necrotrophic