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88 WINES&VINES November 2016 WINEMAKING users to transfer data to a computer through a USB connection. Features of the MegaQuant Wave Many of the enzymatic test kits produced by Megazyme can be performed using the MegaQuant Wave, and for many of these, the test settings are preinstalled and permit automated results analy- ses. The software used by the MegaQuant Wave was developed exclusively for this instrument. As required by many tests used for wine analysis, a major feature is the capability to perform up to four absorbance readings per sample. For tests that are unable to be programmed, the Mega- Quant Wave can be used as a stan- dard spectrophotometer. Another exclusive feature is that the dilution factor of each individual sample can be input while performing that sample test, and the automated results analy- sis will account for that dilution factor. The instrument also comes with the other elements required to run flow-through analyses. On start-up, the main LCD screen shows the four primary menu choices: run tests, manage tests, settings and utilities. The MegaQuant Wave comes with many of the Megazyme test kit procedures preinstalled, including all of the major analytes used for wine analysis. The touchscreen directs the user to the list of tests from which to select an analysis. In order to be accurate, a stylus should be used to scroll through the choices on the screen and se- lect one from the various options. Once a test has been selected, a number of parameters need to be entered prior to starting a test. The system prompts the user to enter the number of samples and usually a blank test for reference. Once the number of samples is entered, the system will prompt the user to in- sert the first tube. At this stage the user must also enter the dilution factor of each sample, and this is accounted for in the final calcula- tion of results. The user then pre- pares the first round of reagent additions to the series of tubes scheduled for analysis and waits the appropriate amount of time for the enzyme to incubate. After the initial incubation pe- riod, the tubes are inserted se- quentially into the instrument. When the first absorbance read- ings are completed, a second round of reagent additions is re- quired. The user adds the appro- priate reagents to the sample tubes and waits for the second incubation period to complete. The tubes are then inserted into the instrument to record the sec- ond round of absorbance readings; results are calculated, stored and printed or output to a computer using SFCapture so that no results are lost. To conserve the system lamp life, there is an automatic lamp shut off if too long a period of time elapses between the initial setup and the last activity. The delay to restart the lamp is only about 40 seconds. The additional equipment needed to run the enzymatic tests includes some automatic pipets and tips for injecting the reagents and samples. Today there is a wide range of automatic pipets from which to choose, ranging from simple pipets from Dynalon for less than $30 for a single volume dis- penser to options well above $100. There are also pipets that are multi-volume dispensers that cost several hundred dollars. Be sure to check the lower priced pipets for their accuracy, as some are very affordable and can be accurate for up to 5,000 injections. The down- side of these less expensive pipets is that they are not repairable, whereas the better quality pipets are. To perform the majority of the enzymatic tests used in wine analy- sis, only two or three multi-volume pipets are required (1 ml, 200 mi- croL and 20 microL). Megazyme recommends using the disposable 12 mm borosilicate tubes with the MegaQuant Wave. These tubes are very inexpensive and, with care, can be reused sev- e r a l t i m e s b e f o r e t o o m a n y scratches make them not useful. Another consideration is the time it takes to clean between uses, which may be the best reason to just dispose of them. Depending on the Megazyme test, the standard full-size test vol- ume is about 3 ml. However, a major advantage of the Mega- Quant Wave is that the cost per test can be reduced by half, if half the volumes of all reagents are used in the test, thereby obtaining twice as many tests per kit. Performing the tests with these lower volumes is easily achieved using the recom- mended 12 mm borosilicate tubes. When evaluating whether to pur- chase an instrument that has an important component of the total cost, it is important to factor in the cost per analysis for each manu- facturer. When making that com- parison, be sure that the evaluation is based on the same criteria. Megazyme, Randox and Astoria- Pacific have different volumes of reagents that are used, and a win- ery's cost should be evaluated based on the amount of reagent that will be used in that winery. Don't compare the cost of one company's full volume analysis to another's half volume analysis cost or the cost of even smaller volumes of test reagents. Another important consider- ation is test accuracy. When one is adding 20 µl and the volume is reduced to 10 µl, there is a greater chance that a larger error will be introduced in just the natural variance of the reagent added to the sample. The advice in this case is: Don't try to save on the cost of the analysis until you know your average error. In my laboratory I have run acetic acid, L-malic acid, glucose, fructose, SO 2 free and total tests on this instrument. Every one of the test results came well within the standards expected for any wine analysis. The precision of the tests was excellent. In the malic acid test, for example, it is not unusual in a triplicate test to have results that varied by no more than 3 ppm on a 50 ppm sample. It should be noted that Unitech Scientific has what appears as a similar instrument to Megazyme. It is slightly more expensive but, more importantly, does not contain the exclusive software of Mega- Quant Wave and therefore does not offer the same functionality. Randox Monza The Randox Monza has many of the same functional abilities and procedural steps as the Mega- Quant Wave. The table "Analysis ENZYMATIC ANALYSIS EQUIPMENT SUPPLIERS Company Phone Website Advantage Bundling SP (866) 286-3546 onestoplabsupplies.com Alpine Scientific (530) 756-6082 alpinescientific.com Astoria-Pacific International (800) 536-3111 astoria-pacific.com Beckman Coulter Inc. (714) 993-5321 beckmancoulter.com Bruker Optics– Bruker AXS Inc. (608) 276-3000 brukeroptics.com Cynmar Corp. (800) 223-3517 cynmar.com Enartis USA (707) 838-6312 enartis.com Forston Labs (800) 301-1259 forstonlabs.com Hach Co. (800) 227-4224 hach.com Hanna Instruments (800) 426-6287 hannainst.com/usa Optek-Danulat Inc. (888) 837-4288 optek.com Megazyme (312) 212-4361 megazyme.com Randox Food Diagnostics (304) 728-2890 randoxfood.com Shimadzu Scientific Instruments (800) 477-1227 shimadzu.com Thermo Fisher Scientific (800) 225-1480 thermoscientific.com/water Unico (732) 274-1155 unicosci.com Unitech Scientific LLC (562) 924-5150 unitechscientific.com Veris Technologies Inc. (785) 825-1978 veristech.com Vinotec Napa (707) 953-7072 vinotecnapa.com Vintessential Laboratories (613) 598-72242 vintessential.com.au VWR International (951) 303-4553 vwr.com For more information about the suppliers listed above, visit winesandvines.com/buyersguide or see Wines & Vines' 2016 Buyer's Guide.