Preparing and Sending Samples

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 […]