Smoke Taint in Grapes and Wine : Factsheet

What is smoke taint?

Smoke from fires, particularly bushfires, can affect the flavour of grapes. The impact of smoke on grapes and the resultant wine varies considerably and a lot of research is being done at the moment to better understand this important issue.

Wine made from grapes that have been smoke affected have been described as having some of the following attributes: “burnt” “ashtray” “charred” “salami” “disinfectant” etc. Wine can be unfit for sale if the taint is too great.

When are grapes most susceptible to smoke taint?

The time of the season is critical for the impact that smoke uptake can cause....

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ANCHOR® Yeast Australian Distributors

Vintessential is now the Australian National Distributor for ANCHOR®, the Leading New World Wine yeast. 

All ANCHOR® winemaking products are now available for prompt delivery throughout Australia from Vintessential.

The ANCHOR® range caters for a wide range of wine styles.

The products available for vintage 2012 are:

• Alchemy I - A yeast blend to enhance aromatic esters in white wines
• Alchemy II - An aromatic yeast blend to enhance volatile thiols in white wines
• Exotics 
• N96 - A strong fermenting, all-purpose wine yeast 
• NT112 - A yeast for producing full bodied red wines
• NT116  
• NT202 - A yeast for the production of aromatic red wines
• NT45 - A...

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Measuring Yeast Assimilable Nitrogen (YAN)

Maintaining an adequate supply of nitrogen is essential for a successful fermentation, as both deficiency and excess of nitrogen can cause problems.

Increased production of hydrogen sulphide is associated with low nitrogen availability, which can then lead to sluggish or stuck ferments.

Conversely, excess nitrogen present at the completion of fermentation can be used by undesirable microorganisms, which can lead to wine spoilage.

Managing nitrogen levels is necessary to avoid these problems and to maximise the control you have over the fermentation.

This is initially achieved through vineyard practices such as the application of nitrogen-containing fertilisers. However, many factors can affect the level of nitrogen...

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Vintage Woes

Introduction

Another vintage and the usual suspect samples, and more, arrived in our laboratories. The main feature of this vintage that will be remembered is the highest atmospheric temperatures ever recorded in Southern Australia. The temperatures in the high 40s on the Celsius scale that were experienced in February affected fruit throughout South East Australia with many vineyards having fruit that was burnt or shriveled. The high temperatures also contributed to the tragic Victorian bushfires that caused loss of life and property. Many vineyards were also affected with fruit that was tainted from smoke exposure.

Smoke taint

Without doubt the main issue we...

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All you ever wanted to ask about wine tannins but were too afraid to ask

Introduction

The topic of tannins is about to come up at the Annual ASVO Oenology seminar on October 6th in Adelaide. To try and prepare those attending the seminar, the following article discusses some basic concepts about tannins and their application in wine. It’s difficult to discuss tannins without getting into some serious chemistry; so the article starts as simply as possible for those who haven’t studied chemistry (and for those who did some Wine Chemistry but who forgot the details once they walked out of the exam room!).

What are tannins?

The name tannin originally comes from the leather industry. The...

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Smoke taint in Winegrapes from the Victorian Bushfires of 2009

Introduction

In the May 2007 issue of Grapegrower and Winemaker we discussed the impact of smoke from bushfires in the North East and Eastern regions of Victoria on grapes grown in these and surrounding regions (1). This current vintage has seen an unprecedented incidence of bushfires in Victoria, in several cases involving vineyards being burnt. The consequences for the 2009 vintage are, at the time of writing this article, not totally determined but are expected to be more severe than 2007.

The 2009 Victorian bushfires

The horrific bushfires that have occurred in Victoria, starting on 7th February, have seen the greatest loss...

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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 of checking that your lab is running well and doing what it is supposed to do: generate accurate data so that sound decisions can be made during the winemaking process in the rush of vintage.

Consumables

One of the major upsets that can happen in a busy laboratory, such...

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Malolactic Fermentation Monitoring

Introduction

Accurate monitoring of Malolactic fermentation (MLF) is one of the most critical analytical parameters in red winemaking, but one that is commonly overlooked prior to bottling. We are often asked to investigate causes of red wine spoilage, and one of the first questions we ask the winemaker is “what was the malic acid concentration prior to bottling?” Unfortunately, many winemakers simply do not bother to check or assume that MLF has gone to completion based on no more visible signs of fermentation, or by using qualitative methods such as Paper Chromatography.

Types of test available

This paper will only discuss methodologies available...

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Successful Malolactic Fermentations

Introduction

Malolactic fermentation (MLF) can be one of the most problematic areas that a winemaker has to manage. The advent of commercial preparations of bacterial cultures for MLF has both simplified and improved this difficult area. Research is ongoing on MLF and the results of this work is helping to further improve these preparations and thus helping to make MLF less troublesome.

Background

Along with D-tartaric acid, L-malic acid (malic acid) is the other major acid to be found in grape juice. Other acids such as citric acid and acetic acid can also be found in juice in smaller amounts. Of the major...

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Managing potential microbial problems during crushing or pressing grapes

Introduction

The crushing or pressing of grapes may seem like one of the simplest parts of the winemaking process, however it is at this stage that problems may start which will affect the quality of the wine at a later stage. These problems are mainly related to the microbiology (and related chemistry) of what is happening in the must once the crushing or pressing has taken place.

Grapes skins

Problems can arise once the grape skin is broken. The precious skin of the grape berry has done well to protect its contents from rain, heat and microbial pests throughout the growing season. The...

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