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W i n e s & V i n e s M A R C H 2 0 1 4 79 WineEast Alcohol has both a different refractive index and a different spe- cific gravity than water, and its presence will introduce significant errors in your readings when a refractometer is used to measure soluble solids. While a refractometer is used prior to beginning fermentation, the hydrometer is used during both harvest and fermentation. Be sure you have enough tubes to allow the hydrometer to sink its full length. A lab should have at least one that will cover the range of grape soluble solids, typically from 0° to 30° Brix. This hydrometer is not expensive. If you need one for high-Brix grapes such as late-harvest, limited-range hydrometers, such as one for 30° to 45°Brix, are available. Most importantly, be sure you have a +5° to -5° Brix hydrometer. This type is not as inexpensive as the 0° to 30°, but it is highly useful to determine accurately when fermentation has ended. These fragile devices can be protected by a cover made out of PVC pipe. Glue a cap on one end of the correct diameter pipe and place a piece of foam in the tube. Then put another cap on the other end. It won't protect a hydrometer that is dropped, but it will protect against something tipping onto it. Total acidity Every laboratory should have glassware to run the manual wet chemistry tests such as the burettes used for total acidity tests. However, this equipment is not the best way to run routine total acidity tests. For a complete total acidity analysis you will need a hot plate or microwave, burette stand, holder and burette, and a pH meter. It will take several minutes for the first test, but after that, you can run several tests fairly quickly. Even if you plan to run more tests later that day, do not leave reagent in the burette because it will start to evaporate and could alter your results. Many people put this reagent back into their stock bottle because they don't want to waste it, and because of the time it takes to make and standardize the stock and working solutions. However, it does not take much to alter the standardized solutions, and then errors can occur. It is preferable to get one of the simple titrators made by Hanna Instruments, which allows titrating from standardized solutions. Setup time is reduced, you can run one or a dozen tests, and it makes little difference in the overall time to run one test from another. It's easy to clean up and maintain. Over the long haul, it is more cost effective that the manual method, and because it is easy, everyone has the incentive to run the test. Calculating pH There are many fine pH instruments on the market. However, this is one case where you need to spend some money, as the cost is almost always directly related to the precision and accuracy of the output. Just because some manufacturers claim to have a certain level of accuracy doesn't mean they will be able to make that mea- surement for long or repeatedly. The ideal lab would have a bench measuring meter and a port- able one to take to the bin/tank and measure directly from the container. If you must make a choice, get the bench model. It will EASTERN WINE LABS Serving the Analytical needs of East Coast Wineries WWW.EASTERNWINELABS.COM Ph 609-859-4302 Cell 609-668-2854 chemist@easternwinelabs.com AOAC Member EasternWineLab_Mar09.qxp 1/22/09 9:47 AM Page 1 Basic Hoe comes with a Hillup and a Takeaway Blade. Additional attachments include .3 Tooth Cultivator, Undercutter Blade, Rotary head, " NEW " Rolling Cultivator and "Vine Auger". The Green Hoe Company, Inc. 6645 West Main Road, Portland, NY 14769 PHONE (716) 792-9433 FAX (716) 792-9434 WWW.GREENHOECOMPANY.COM GREEN GRAPE HOE Trellis Supplies • Notched Metal Post, Wood • Anchors • Wire • Tools • Gripples • Dura-Line Training & Tying Supplies •Tree-fix • Wire ties • AgLoc • Klip-on • Grow Tubes • Training Stakes • Tying Products Wildlife Control • Bird netting • Side Applied Netting • BirdGard • Scare Devices • Deer Fence & Deterrents Spring Pruning and Tying Supplies FINGER LAKES TRELLIS SUPPLY BUY ONLINE! www.fingerlakestrellissupply.com 315-904-4007 4041A Railroad Ave. info@fingerlakestrellissupply.com Williamson, NY 14589