Tips
Obscuration, Unsatisfactory Bentonite and Sulfur Dioxide Strikes Again! – Testing Times May 2017
Introduction This month we look at some more curly issues we’ve received in the lab. Helping to solve them has involved some intricacies of testing and we’ve had to call upon our many years’ experience in sorting out some of these problems in our own laboratories. Sulfur dioxide test problems – again! Many wineries do […]
Safety considerations in your wine lab this vintage
Greg Howell Vintessential Laboratories Vintessential has built and opened three new wine testing laboratories in the past year – in Orange New South Wales, Hobart Tasmania and the Margaret River region of Western Australia. If our experience is any guide, your lab may be working outside the requirements of the appropriate Australian Standards! A winery […]
Tip: pH Electrode Care
pH ELECTRODE CARE Never leave the electrode in juice or wine for longer than it takes to get a stable measurement of pH. Tannins, proteins etc in the sample can build up on the membrane and cause a sluggish response. Take the measurement, then rinse the electrode immediately with distilled […]
Tip: The importance of climate change (in your lab!)
It’s winter and it’s cold. But it needn’t be in your lab. Having well maintained heating and cooling systems in your lab is necessary to keep the temperature as close to 20˚C as possible. This not only makes for a comfortable and safer working environment, it can be critical in achieving accurate results. Here are […]
Tip: Measuring dissolved CO2 in the winery
The level of dissolved carbon dioxide in a wine can greatly effect the taste of the wine, too little and the wine can seem flat and flabby and too much can cause a wine to taste harsh and tannic. Measuring carbon dioxide in the winery can be done a number of ways but the quickest […]
Tip: Using spike analysis as a QC in the lab
Many wine labs now have improved quality control systems in place and routinely analyse samples in duplicate and run the same control wine sample each day, plotting the results on control charts. These are great ways to monitor repeatability and reproducibility, two very important quality parameters that indicate how precise a method is. A third […]
Tip: Troubleshooting enzymatic calibration curves
With an increasing number of labs upgrading from benchtop spectrophotometers to automatic discrete analysers for their enzymatic testing, it is worth noting that the major difference between the two approaches (apart from speed!) is in the calculation of the sample results. A discrete analyser calculates a calibration curve from a series of known standard solutions. […]
Tip: Conducting micro testing without a micro lab
In a perfect world a winery micro lab would be established in its own room, separate from any other winery or lab activities. It would have a laminar flow cabinet and dedicated personnel trained in aseptic techniques. In practice, space and budget constraints don’t always allow for this, but that shouldn’t prevent labs from adding […]
Tip: A closer look at absorbance
Absorbance readings taken from spectrophotometers during enzymatic analysis should be considered carefully before they are used to calculate important wine parameters. Many spectrophotometers have a photometric range up to about 3.0 absorbance, but this does not necessarily mean that any value up to 3.0 is an accurate reading. Spectrophotometers don’t directly measure absorbance, they actually […]
Tip: Cuvettes – a closer look at a common consumable
You use them every day for your enzymatic analysis and probably don’t think too much about them. But the quality and correct use of your disposable cuvettes are critically important for ensuring accurate enzymatic or colorimetric results. We use high quality disposable cuvettes in our NATA accredited labs, for analysis as well as for validation […]
Tip: Correct micropipetting technique
One of the most crucial factors in enzymatic analysis is volumetric accuracy. Taking care to properly use and maintain micropipettes will save you time, money and frustration in the long run. It helps to pre-wet new pipette tips by aspirating and dispensing the liquid before pipetting. This forms a thin film on the inner wall […]
Tip: Cuvettes – a closer look at a common consumable
You use them every day for your enzymatic analysis and probably don’t think too much about them. But the quality and correct use of your disposable cuvettes are critically important for ensuring accurate enzymatic or colorimetric results. We use high quality disposable cuvettes in our NATA accredited labs, for analysis as well as for validation […]
How to fix Stuck and Sluggish Fermentations
Stuck and sluggish fermentations can be a major concern during vintage and, in the worst cases, lead to irreversible wine spoilage. Problem fermentations are now better understood, which makes it possible to use prevention tools such as selected yeast strains, yeast hulls and winemaking practices. Restarting stuck ferments with Fermichamp yeast Stuck and sluggish fermentations […]
Tip: Calibration Procedure for Micropipettes
SCOPE This procedure describes the method generally used to calibrate all micropipettes. Check the individual manufacturer specifications for acceptable error ranges at nominal volumes. RECOMMENDED FREQUENCY Every 3 months REAGENT REQUIREMENTS • Distilled Water PROCEDURE 1.1 Each pipette should be tested at its maximum capacity, and again at no more than 20% of its total capacity […]
Do you know what levels of trace metals are in your wine?
Introduction Wine contains a number of metal ions in very small, that is, trace amounts. These trace metals are generally harmless and in fact can be essential micro nutrients for humans. Most countries have legal limits on the level of certain trace metals in wine. The recent change in limits on manganese in China is […]
Winemaking with grapes affected by Botrytis cinerea
Botrytis cinerea is a weather driven fungus which causes the grapevine diseases botrytis bunch rot and grey mould. The ideal conditions of its development are humidity, high crop density, and important vegetation development with the following consequences: Poor juice yields. Low must nitrogen and vitamins content, due to the consumption by Botrytis cinerea for its […]
A simple and easy way to organise your lab for vintage
Introduction Prior to your busy vintage period, it’s important to be as organized as possible in your laboratory. One way to do this is to generate 3 main lists of what you require to effectively run your lab – we show you how below. By having all the tests you do documented as Test […]
Can petiole analysis help improve wine quality?
Introduction The time of year has come when the nutrient levels in grapevines are usually analysed. The article below explains the reason behind this widespread practice and how to avoid problems with testing, plus how this information can be used to help improve wine quality. Nutrients Like all plants, vines need certain nutrients to ensure […]
Why use enzymes in winemaking?
Enzymes are commonly used in winemaking. However, unlike yeast where the impact on the juice or must is easily observed and measured, the impact of enzymes is not so obvious. This article spells out the major applications of enzymes in winemaking and highlights the benefits of using these useful products. What are enzymes? Enzymes are naturally – occurring proteins. Each particular enzyme has a specific structure. […]
