Resources

Winery Effluent Water Testing

Knowing your waste is the first step to developing and maintaining a wastewater management system that works for your winery. The composition of your wastewater will change during the course of the season (vintage to non-vintage), so regular monitoring is crucial to understanding its characteristics and to developing effective treatment strategies. Analysis of wastewater post […]

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. […]

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 […]

Sparkling Wine: a peculiar lab sample

Introduction Sparkling wine is a bit of a strange substance to work with in a laboratory as it contains those pesky bubbles. Of course the bubbles are why we call it sparkling wine. But what exactly do we mean by ‘sparkling wine’? Sparkling wine – the Australian definition The definition actually varies from country to […]

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 […]

Yeast based wine additives – Are the many claims made about these products justified?

Introduction There are a number of products made from Inactive Dry Yeast (IDY) that are used in various ways in modern winemaking. Many claims are made about their properties and benefits, however not all these claims have been scientifically proven leading to some confusion amongst winemakers. This article looks at the proven benefits of these […]

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. […]

Nitrogen compounds and supplements

January 2013 Introduction Yeasts have a strict need for nitrogenous compounds during fermentation of grape juice. Most grape must is deficient in nitrogen and so supplements are normally added to increase the level of nitrogen compounds in the must. By having a sufficient level of nitrogen, the yeast can ferment the must to dryness with […]

New developments in Botrytis cinerea testing

Introduction The following is a written version of a presentation by the author to a meeting of the Interwinery Analysis Group in Adelaide on 26 July 2013. Botrytis cinerea – What is it? Botrytis cinerea is a common mould that occurs on many fruits. If you have ever seen strawberries with a grey fuzzy mould […]

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 […]

Irrigation Water Analysis

DO YOU KNOW THE QUALITY OF YOUR IRRIGATION WATER Water quality guidelines recommended for irrigation and general on-farm and domestic use have been developed by the Primary Industries and Natural Resource Management Ministerial Counicils. The guidelines cover several water parameters that should be analysed to ensure your water is suitable for its intended use. At […]

Grapevine Petiole Analysis

Petiole testing can provide a snapshot of the nutrient status of the vine. Obtaining quantitative information on nutrient levels can assist in determining the effectiveness of fertiliser applications and also help identify the cause of any specific vine problems. The following table outlines nutrient guidelines for the full list of parameters tested in our Petiole […]

Allergen Residue Analysis

From 1 July 2012, new allergen labelling requirements came into effect in the European Union (EU). If milk (casein) or egg products have been used and the wine has not tested negative for these residues using a technique with a detection limit of 0.25mg/L, then the presence of allergens must be indicated on the label. […]

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 […]