The use of macerating enzymes and fermentation tannins to enhance red wine colour and structure
Pectin, cellulose and hemicellulose are structural polysaccharides in the middle lamella and primary cell walls of grape cells (Ducasse et al. 2010).)Grape skins contain approximately 75% more cell wall tissue than grape pulp (Vidal et al. 2001).
Results from the 2013 South African vintage red wine enzyme trials
The use of enzymes in white wine production is standard in most wineries. The use of red wine enzymes is less common, with many winemakers who feel "their wines have enough colour" or "there is not really a way to tell if it worked or not."
Ensuring high quality wine production through the use of Dynastart® in yeast rehydration (2012)
With effective yeast protection and appropriate nutritional management, the winemaker can ensure a regular and complete alcoholic fermentation (AF), produce quality wines and avoid organoleptic deviations or adverse effects on the onset of malolactic fermentation (MLF).
Effect of rehydration nutrient on the production of volatile sulfur compounds by active dry wine yeasts (Febuary 2012)
It is well known that the concentration of aroma compounds produced by the yeast Saccharomyces cerevisiae is a function of nutrient availability. During wine fermentation, yeast utilise the nutrients found in the grape juice and produce an array of volatiles such as esters, higher alcohols, volatile fatty acids, carbonyls and sulfur compounds...
Tools for managing Brettanomyces in wines (January 2012)
Brettanomyces bruxellensis yeasts produce a number of compounds that can spoil wine. Volatile phenols (4-ethylphenol [E4P] and 4-ethylguaiacol [E4G]) are associated with dreaded animal notes. Although this depends to a great extent on the wine, the 600 μg/L content ([E4P] + [E4G]) is retained as the alteration threshold. For primeur wines, this value is lower and is higher on the contrary, for high quality, long life wines.
Press wine improvement through an early and appropriate fining (October 2011)
In red winemaking, press wines account for a significant part of the volume. Beside the quantitative aspect, these wines have qualitative aspects that winemakers can benefit from by blending them with free run wines. Rich in phenolic compounds and in color, press wines bring roundness and volume to the blend, therefore nicely complementing wines that may lack structure..
Assimilation of organic and mineral forms of nitrogen by the yeast during alcoholic fermentation.An impact study on fermentation kinetics (September 2011)
Careful management of the yeasts nutritional requirements during alcoholic fermentation is essential to ensure a healthy and complete fermentation. Nitrogen, minerals, trace elements and vitamins, are all essential compounds that contribute to the vitality of the yeast.
The role of certain residues from phytosanitary treatments in bacteria inhibition during malolactic fermentation in wines. (July 2011)
Malolactic fermentation (MLF) is a major concern for winemakers. A number of parameters must be considered and integrated in order to be able to trigger MLF. In the last few years, the use of selected Oenococcus oeni strains has become commonplace. Preventive inoculation techniques ensure satisfactory success rates, but difficulties persist in certain situations...
Use of non- Saccharomyces yeasts for the vinification of Tempranillo
Companies in the wine sector working on developing biodiversity know that the initiation of spontaneous alcoholic ferments (wild ferments) does not result from only one species, nor from a specific yeast strain. The wine, after spontaneous alcoholic fermentation, is the sum of fermentative actions from different species which colonize the medium in sequential steps during the course of the fermentative process. As a result, the outcome and final product is unique for each fermentation.
Citric acid metabolism in lactic bacteria and controlling the diacetyl content in wine
Diacetyl (2,3-butanedione: C4H6O2, Figure 1) is an acetoinic molecule responsible for the ’buttery’ character perceived in wine during malolactic fermentation (MLF), which is by no means universally appreciated by wine tasters.
The effects of fermentation temperature and co-fermentation on the wine aromatic composition of sauvignon blanc
A series of temperature-controlled fermentations In Sauvignon blanc juice were conducted in order to evaluate the responses of yeast in both single and dual-strain environments.
Biogenic amines : avoid spontaneous MLF
Although consequences are considered moderately dangerous, biogenic amines are the second cause of food poisoning in Europe. For sensitive consumers, they suffer headaches, flushing and nausea.....
Maximising aroma preservation in white and rosé wines
All winemakers are concerned with quality, to greater or lesser extents within budget constraints. In terms of white winemaking, the appearance of the wine is secondary to the nose of the wine, so it is critical that a wine of quality be expressive of both varietal characters and terroir.
Impact of fining treatments on juice quality
In terms of juice handling, international winemaking practices vary significantly from country to country. In Australia, as in many other countries, it is typical to treat the free-run and pressings fractions of juice separately, whilst in India winemakers do not always take a pressings fraction.
Fining agents part 1: Proteinaceous fining agents
This is the first in a two-part series of LAFFORT inforbriefs on fining agents. In Part 1 we focus on proteinaceous fining agents, which are commonly used for the removal of phenolics. Discussions are presented to support the characteristics of each fining agent.
Fining agents part 2: Non-proteinaceous fining agents
In Part 2 of this series on fining agents, we analyse the non-proteinaceous fining agents. This includes a discussion of the structures of fining agents and what they are typically used for, including the new egg albumin alternative, BIOLEES®.
Techniques for dealing with awkward malolactic fermentations
Alcoholic fermentation (AF) is generally followed by a second process, malolactic fermentation (MLF), caused by lactic bacteria, mainly Œnococcus œni species. This reduces acidity in the wine and develops its aromas, as well as ensuring microbiological stabilization.
Optimizing the aromas of wines made from Sauvignon Blanc and other grape varieties with «Sauvignon» aromas: impact of a yeast rehydration nutrient and inoculation with mixed yeasts
Saccharomyces cerevisiae winemaking yeast is the key factor in enabling must to express its aromatic potential (Murat et al., 2001, Swiegers et al., 2005; Dubourdieu et al., 2006). Several metabolic pathways are involved in forming aromatic compounds, such as fatty acids and higher alcohols.
Zymaflore FX10® : Using directed breeding to improve a reference strain unsuited to modern winemaking conditions
Tannins vs. oak chips: what does each contribute to your wine?
Prefermentation maceration in red winemaking: risk control and alternatives
Low-temperature prefermentation maceration is undeniably useful for producing fruity wines. However, this technique involves a certain number of microbiological risks. There must be adequate cooling capacity to maintain a sufficiently low temperature, as there is a real risk that indigenous flora will grow, leading to poor development of selected yeasts, sluggish fermentation kinetics, or even organoleptic spoilage.
Yeast strain and nutritional modulation of aroma intensity, longevity and winemaker preference in Sauvignon Blanc wine*
Recently we have focused much research on the impacts that yeast strain and yeast nutritional status have on the production of both varietal and non-varietal (ie fermentation-derived) aroma production in Sauvignon Blanc (van der Westhuizen et al., 2008; Swiegers et al., 2008). Saccharomyces cerevisiae winemaking yeast is the key factor in enabling must to express its aromatic potential (Murat et al., 2001, Swiegers et al., 2005; Dubourdieu et al., 2006).
Stuck ferments: causes and solutions
An analysis by LAFFORT of the possible causes for stuck fermentations and more importantly, ways to treat them, has led to a strategic approach to the effective management of stuck fermentations, coupled with the innovative use of products purpose-designed for problem solving. Even in a very difficult year for stuck fermentations, such as 2008 in South Australia, the stuck fermentations experienced were corrected using the LAFFORT protocol.