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January 2018 WINES&VINES 93 WINERY & VINEYARD EQUIPMENT www. .com Setting new standards in test technology Find out why our loyal customers include some of the biggest names in winemaking. Your trusted partner for quality control in the wine industry US distributor Booth 1740 tity for later results). Follow with 3 ml sterile water to rinse any residual sorbate. Open a Biosart Media ampoule and place on the filter disk. Immediately remove the funnel wall place the funnel top on the filter base and cap the bottom. Incubate in a warm spot for three days and check for growth. Biosart has photos to guide the procedure. pH: a small footprint meter The most important factor in pH measurements is probe quality and its maintenance. Based on experience, accurate measure- ments from a probe that has been properly cared for is about 18 months, even if it is used infre- quently. The Edge meter has cali- bration reminders and GLP (good laboratory practices) icons to re- mind you of maintenance times. SO 2 : so simple to run With the Hanna mini-titrator, the free SO 2 and total SO 2 tests are conducted essentially in the same way, only using different reagents. The testing protocol for both tests is Ripper chemistry-based. The CDR WineLab and MegaQuant Wave use similar enzymatic based chemistry in their instruments. For CDR WineLab, different test kits are used to distinguish be- tween free and total SO 2 . Mega- zyme's MegaQuant Wave has three combinations of test kits for SO 2 . A combination kit that has both free and total analyses, one with only free and one for total. Each have the same number of tests per kit. For the Hanna titrator, the free SO 2 takes a shorter time to run than total because the total test requires time to break the bound form into free before the analysis can be run. For CDR WineLab and the MegaQuant Wave, the timing is the reverse. Using the Hanna instrument for measuring free SO 2 , the acid reagent and potas- sium iodide are added to the sample and the test is begun. The titrant measures the inflection point in the titration curve and calculates the ppm of free SO 2 . For the MegaQuant Wave, the free SO 2 test is based on fuschin and aldehyde binding. The tests using CDR are basically the same as the Megazyme tests. The lowest amount of free SO 2 detectable by the Hanna ti- trator is 1 ppm, for the Mega- Quant Wave 2 ppm and for CDR WineLab 1 ppm. For both MegaQuant Wave and CDR, the total test is based on thiol groups. The MegaQuant Wave uses Ellman's reagent and CDR uses a proprietary reagent. The lowest amount of total SO 2 for the Hanna titrator is 30 ppm, for the MegaQuant Wave it is 5 ppm and for CDR WineLab it is 15 ppm. Titratable acidity: step motor accuracy, and quick A defined function mini-titrator was one of the best advances in lab analysis when this particular instrument was released. The step motor advance was essential to this meter's position in this arena. CDR has stepped up the game with this titrimetric method of analysis. The lowest amount of acidity that the Hanna titrator can mea- sure is 0.1 g/L, and for the CDR WineLab it is 1 g/L. Upgrade lab procedures along with lab technology All small to medium-sized win- eries should evaluate their labo- r a t o r y, u p d a t e t h e i r g o o d l a b o r a t o r y p r o c e d u r e s o n a regular basis, and then upgrade the lab to incorporate the best analysis technology they can find for their needs. It should be noted that no matter the size of the laboratory, all analyses should be under con- stant examination, whether wet chemistry-based or the advanced techniques described here. On a regular basis (once a quarter, semiannually or at least once per year) all tests should be verified that they are within a standard error by an outside source such as ETS Laboratories. Richard Carey, Ph.D., is a wine consul- tant in Lancaster, Pa., and owner of Ta- manend Wine Inc. He wrote a software program to help small wineries keep track of their wine production records and results of laboratory analyses. He would like to thank the suppliers who provided the equipment that he used for this article.