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46 W i n e s & V i n e s A P R i L 2 0 1 4 I n the March 2014 issue of Wines & Vines, I described the basic wine lab- oratory and discussed the minimum laboratory equipment and analytical procedures for soluble solids, total acidity, pH, ethanol, sulfur dioxide and sample preparation. In this article, I will examine more complex testing proce- dures, the equipment needed to run those tests and different strategies to get your best analysis "bang for the buck." Bottled wine integrity One of the most challenging aspects of winemaking, but absolutely one of the most important, is ensuring the integrity of the final packaged product. To maintain the public's trust, wineries must be certain that the wines they release are stable. Microbiological testing of the wine is essential to having that assurance. This is an area where most winemakers and many laboratory personnel are out of their ele- ment. What looks clean is not necessarily so from a microbiological perspective. To gain that assurance, many wineries send samples to an outside service laboratory. The full micro-analytical set-up can be quite costly, and it includes acquisition of some way to sterilize equipment. Some basic supplies are also necessary, such as transfer hoods, and the media and plates to measure the bottles in question. However, there is a testing approach where many difficulties can be reduced, if not eliminated, for those wanting a more immediate, hands-on understanding of their bottle integrity. One of the better systems has been developed by Sartorius. They have a prepackaged filter unit called Biosart that comes with a grid. They also have a wide selection of media that helps select the microbes that might be present in a bottle. With just a little bit of preparation and practice, it is possible to get a good idea of the integrity of a bottling run about four days after bottling. If this system is used as a screening test, only those sam- ples that fail the testing procedure need to be sent out for analysis and validation. When a winery adopts this type of sys- tem, that winery can sample more fre- quently and know from the start that a particular bottling was clean. Amino and ammonium nitrogen The easiest and least expensive test for fer- mentable nitrogen uses the Formol test. It is a simple titration of the ammonia ion in the free form and amino acid-derived ammonia. This test is conducted by titration with formaldehyde. If a winery laboratory does not have a spectrometric instrument, this test is the best way to determine the fer- mentable nitrogen level of juice. Dr. Barry Gump of Florida Interna- tional University developed a new version of this test that combines the analysis of fermentable nitrogen with total acidity analysis (reference). By first running total acidity, the result is a sample titrated to pH 8.2. Then by adding formaldehyde to that sample and re-titrating, it is possible to determine fermentable nitrogen. Even more important, if a winery has one of the auto-titrators such as the Hanna 901, all it takes is to switch the program from TA to Formol, add the formaldehyde and push the button. The most complete solution is to pur- chase one of the multi-purpose enzymatic titrators such as the Randox Monza. With one of these instruments it is possible to analyze many different substances in a wine. The enzymatic method allows dis- crimination between free ammonium ions and those associated with amino acid- derived ammonia. This will tell you more about the overall health of your grapes, which will help inform your vineyards on best practices for their grapes. Ramping Up Your Winery's Lab Second installment in wine lab series discusses more complex equipment and testing By Richard Carey When Maryland's Boordy Vineyards built its new space (see "Ready for the 21st Century" in the December 2013 issue of Wines & Vines), the owners set aside a dedicated laboratory area. W I N E M A K I N G