Tips
Is there too much residual copper in your wine?
The use of copper sulfate for fining in wine is well established and widely used. The level of residual copper is highly regulated and, yet, does not appear to be regularly checked by many winemakers. Based upon the results of our testing for residual copper this year, we outline why some caution is needed with this additive. Sulfide […]
Lets be clear about filtration
Introduction Filtration of wine is normally used as an important step in the final stages of winemaking to ensure clear and stable wine. Discussion of the types and sizes of microbes that can cause spoilage are included to demonstrate one of the main reasons for employing effective filtration. Some of the aspects of filtration are […]
Technical issues when using non-traditional wine packaging
Introduction There are numerous reasons why the use of traditional packaging for wine is changing. These can be for quality, environmental, cost or marketing reasons. Changing the form of the packaging can involve a number of technical challenges and problems, as the recent trend to screwcap bottles has demonstrated. In this article we look at […]
Yeast nutrition and successful fermentations
Introduction Successful primary fermentations of grape juice depend upon a number of factors: nutritional aspects are of critical interest as more becomes known about the nutritional needs of yeast. The following article discusses some of the relevant issues in regard to yeast nutrition in fermentations. Nutrients A number of different nutrient types are necessary for […]
Wine analysis during crushing and pressing
Introduction There are a number of different tests that are done on juice and must at the time of crushing and pressing. These tests are explained below with some new developments in tests and equipment noted. Testing during crushing and pressing The main analyses performed during the process of crushing and pressing grapes are well […]
Mannoproteins – How are they used in winemaking?
Introduction Mannoproteins are a naturally occurring group of proteins found in the cell walls of yeasts. In particular, the mannoproteins in the wine yeast Saccharomyces cerevisiae have been studied extensively. The beneficial winemaking properties of mannoproteins, including tartrate stabilisation, are discussed in this article. Properties of mannoproteins It has been observed for many years that […]
Is the drinking water at your winery safe to drink?
Introduction Laboratory testing for a winery usually is thought of as dealing only with wine, but there is another important liquid that should be tested regularly – your drinking water. If your winery is not on “town water”, that is if you use tank water for drinking water then you may be risking the health […]
Alcohol and Standard Drinks Statements
June 2013 Introduction The accurate measurement of alcohol in wine is relatively easy for experienced laboratory operators with the correct equipment and techniques. The use of this measurement on labels, however, is a regulatory minefield. In this article we discuss the best technique to measure alcohol and the best way to use the data correctly. […]
Care and Handling of Cuvettes
Proper maintenance of quartz cuvettes is an essential part of spectrophotometric analysis. The following notes are based on the recommendations of Australian Standard AS 3753-2001. Cuvettes in regular use should be stored either: a) in a box lined with a suitably soft material (possibly one supplied by the manufacturer); b) immersed in distilled water; c) […]
Survey of Yeast Assimilable Nitrogen Status in Chardonnay and Shiraz Grapes from the Granite Belt 2012 Vintage
Yeast Assimilable Nitrogen (YAN) is necessary for yeast growth and fermentation activity in grape must. It is comprised of two major components, amino acid nitrogen (AAN) and ammonia nitrogen (AN). Maintaining an adequate supply of YAN is essential for a successful fermentation, as both deficiency and excess of nitrogen can cause problems. Low YAN […]
Take care of your pH electrode!
Measuring pH is one of the most important tests in the winery but it can also be one of the most frustrating. A sluggish or non-reproducible response indicates that the pH reading may not be accurate. Can you trust the equipment you’re using? Taking a few simple steps to look after the electrode each time […]
Post Fermentation spoilage compound analysis
With harvest coming to an end in most regions of Australia, many of you will be happy to put the challenges of this growing season behind you! Primary and secondary fermentations are now in full swing which brings a new set of challenges, such as producing wines without excessive levels of spoilage compounds. Three compounds […]
Product Tip: Malic acid testing by Thin Layer Chromatography (TLC)
For best results take note of the following: Sample make sure your Sample spots are as small & concentrated as possible. always allow the spots to dry between applications. Solvent It is most important to ensure the plate is completely dry between the applications of Solvent & Indicator. Use warm air from a hairdryer to […]
Lab Tip: De-gas your TA sample to get accurate results
It is good practice in a winery lab to always degas wine samples prior to analysis of titratable acidity (TA). This is of particular importance at this time of year for wines that have just finished primary or secondary fermentation, as they can contain a high concentration of dissolved carbon dioxide. In wine, carbon dioxide […]
Product Tip : Dilution rates for samples when using Enzymatic Test Kits
The concentrations of the Standards we supply with our kits are designed to give a good working range with a typical spectrophotometer. For example, the Ammonium Standard is typically 40 mg/L (ppm); this gives an absorbance of around 0.5 absorbance units. Likewise the Malic Acid Standard is typically around 0.2 g/L and gives an absorbance […]
Product recommendation March 2012 – Anchor NT50
Anchor NT50: A yeast for producing fruity red wines NT 50 enhances red berries (strawberry, raspberry and cherry), black berries (blackberry and black currant) and spicy aromas in red wines. It is suitable for wine with or without wood maturation. It is most suited for vinifying Shiraz, Grenache, Pinot Noir, Gamay, Cabernet Franc and Zinfandel. […]
Preparing your winery laboratory for vintage
Introduction There are a number of things to consider in preparing your wine lab for vintage. The major areas of laboratory equipment and the consumables needed to run them, the calibrations of the equipment and the standardisation of the consumable solutions are discussed below. The membership of proficiency programs is also promoted as a way […]
Botrytis cinerea: Australian vintage 2011
Introduction The amount of vineyards affected throughout South East Australia by Botrytis cinerea in vintage 2011 was very high. In this article we look at the effects this fungus can have on wine quality, how to test the impacts and what can be done to overcome these effects. What is Botrytis Cinerea? Botrytis cinerea is […]
Automation in the Wine Laboratory
Introduction The introduction of automated methods of testing in wine laboratories has been ongoing for many years. In this article the tests that can be easily automated and the types of instruments available are discussed. The benefits and the problems of installing automated equipment are also outlined. Why automate? One of the main aims of […]
Agricultural chemical residue analysis in wine
Introduction Agricultural chemicals are used widely in the wine industry to ensure that sound grapes are delivered to wineries. The use of these chemicals is tightly controlled by government agencies. Limits are set for the amount of residual chemical that is allowed in wine and elaborate testing is available commercially to ensure that these limits […]
