Impact of heating must before fermentation on Chardonnay wines

The interactions among aromatic compounds and proteins is an important issue for the quality of foods and beverages. In wine, the loss of flavor after vinification is associated to bentonite treatment and this effect can be the result of the removal of aroma compounds which are bound wine proteins. This phenomenon was recently demonstrated for long chain fatty acids and their ethyl esters (1). Since these latter compounds are spectroscopically silent, their association with proteins is not easy to measure.

Viura is a synonym for Macabeo and currently it is the most widely planted white grape variety in D.O.Ca. Rioja, with 3,569 ha, representing 84% of the white grape cultivated area. It is a generous-yielding grape, presenting low values of titratable acidity and with large and compact clusters which makes it susceptible to Botrytis cinerea. Thus, this variety not always satisfies the wine grower’s prospects. Nowadays, the available plant material is scarce, moreover, it was selected on the basis of other quality criteria, not currently requested.

Bioactive polyphenols from grapes and wines, like stilbenes and flavonols (SaF), are often determined to nutritional evaluation, but also for many other purposes. The objective of this study was to quantify SaF in red wines from “Campanha Gaúcha”, a large and young viticultural region from South Brazil. Moreover, through statistical analysis, evaluate the influence of these compounds according to varieties, production process, harvest years and micro-regions of cultivation. A total of 58 samples of red wines were analyzed by high-performance liquid chromatography coupled to diode array detector (HPLC-DAD) for determination of trans-resveratrol (R), quercetin (Q), myricetin (M), kaempferol (K), trans-e-viniferin (V) and their precursor, cinnamic acid (C).

An intelligent packaging might, among others, provide information and allow monitoring of the quality of the packed product or its surrounding environment. A recent project on micro-flow wine bottles closed with aluminium screw cap and tightness liner, highlighted the importance of monitoring the internal overpressure continuously, in real-time and at least for 72 hours, since the internal pressure on the tightness liner and the micro-flow are related. Real-time and continuous measurements are not the standard methods of measurement of the overpressure, yet. The most used equipment for the determination of the pressure in wine bottle is the aphrometer, a destructive device that supplies a single value of pressure.

Fining is a technique that is used to remove unwanted wine components that affect clarification, astringency, color, bitterness, and aroma. Fining involves the addition of adsorptive or reactive material in order to reduce or eliminate the presence of certain less desirable wine components and to ensure that a wine remains in a particular stable state for a given period of time Recently concerns have been raised about the addition of animal proteins, such as gelatin, to wine due to the disease known as bovine spongiform encephalopathy (Mad Cow disease). Although the origin of gelatins has been moved to porcine, winemakers are asking for substitute products with properties and application protocols similar to the traditional animal-derived ones, making the use of plant-derived proteins in fining a practically viable possibility. As a consequence, various fining agents derived from plants have been proposed, including proteins from cereals, legumes, and potato.