The technology of high-power ultrasound and its effect on the color and aroma of rosé wines.

Background: The application of high-power ultrasound (US) has been studied extensively to obtain value-added red wines using short maceration times. It is a technique of wide interest for the extraction of aromatic compounds and compounds responsible for color, so it could also be an important tool to use in the elaboration process of rosé wines. Thus, this study focused on the effect of the application of US on the phenolic, aromatic, and sensorial profile of rosé wines.

Rapid and Non-Destructive Analysis of Corky Off-Flavors in Natural Cork Stoppers by a Wireless and Portable Electronic Nose.

This article discusses the use of a handheld electronic nose to obtain information on the presence of some aromatic defects in natural cork stoppers, such as haloanisoles, alkylmethoxypyrazines, and ketones. Typical concentrations of these compounds (from 5 to 120 ng in the cork samples) have been measured. Two electronic nose prototypes have been developed as an instrumentation system comprise of eight commercial gas sensors to perform two sets of experiments.

Use of Microwave Maceration in Red Winemaking: Effect on Fermentation and Chemical Composition of Red Wines.

The objective of this study was to evaluate the effect of microwave treatment of crushed grapes on the yeast population of the must and on the development of alcoholic fermentation, as well as on the extraction of different compounds from the grapes such as polysaccharides and amino acids that can affect the organoleptic quality and stability of the wine. This study demonstrated for the first time the effect of the microwave treatment of grapes on native yeast species and their diversity, producing an increase in fermentation kinetics and a decrease in the lag phase. The microwave treatment produced a positive effect on the extraction of amino acids and polysaccharides from the grapes, resulting in significantly higher amounts of the main amino acids of the must and some major volatile compounds in the treated samples.

Effect of Microwave Maceration and SO Free Vinification on Volatile Composition of Red Wines.

This study evaluates the effect of microwave treatment in grape maceration at laboratory scale on the content of free and glycosidically bound varietal compounds of must and wines and on the overall aroma of wines produced with and without SO. The volatile compounds were extracted by solid phase extraction and analyzed by gas chromatography-mass spectrometry, carrying out a sensory evaluation of wines by quantitative descriptive analysis. Microwave treatment significantly increased the free and bound fraction of most varietal compounds in the must.

Effect of Power Ultrasound Treatment on Free and Glycosidically-Bound Volatile Compounds and the Sensorial Profile of Red Wines.

This study presents the effect of the application of high-power ultrasound to crushed grapes, at a winery-scale, on the content of varietal volatile compounds (free and glycosidically-bound) in musts and on the overall aroma of wines. Two different frequencies (20 kHz and 28 kHz) were tested and the combination of grape sonication and different maceration times on wine aroma was also evaluated. The volatile compounds were isolated by solid phase extraction and analyzed by gas chromatography-mass spectrometry, carrying out a sensory evaluation of wines by quantitative descriptive analysis.

Evaluation of the Storage Conditions and Type of Cork Stopper on the Quality of Bottled White Wines.

The effects of different storage conditions, light exposure, temperature and different commercially available cork stoppers on the phenolic, volatile and sensorial profile of Verdejo wines were studied. Two natural corks of different visual quality and a microgranulated cork stopper were investigated over one year at two different storage conditions. One simulating light exposure and temperature in retail outlets and the other simulating optimal cellar conditions (darkness and 12 °C).

Effects of the pre-fermentative addition of chitosan on the nitrogenous fraction and the secondary fermentation products of SO -free red wines.

Background: Different red winemaking were carried out to evaluate the effects of the prefermentative addition of chitosan, as an alternative to the use of SO , on the secondary products of alcoholic fermentation, yeast available nitrogen (YAN), biogenic amines and ethyl carbamate.

Results: The wines made with chitosan presented higher total acidity and higher content of tartaric and succinic acids than those made only with SO . The use of chitosan in winemaking resulted in wines with higher glycerol and diacetyl content without increasing the concentration of ethanol, acetic acid, acetaldehyde or butanediol.

Effect of Wine Lees as Alternative Antioxidants on Physicochemical and Sensorial Composition of Deer Burgers Stored during Chilled Storage.

Wine lees from two grape varieties ( L. Cv. "verdejo" and "palomino") were studied as natural preservatives in deer burgers compared with the traditional additive sodium ascorbate.

Mango by-products as a natural source of valuable odor-active compounds.

Background: The aromatic potential of mango by-products was evaluated to seek natural and cheap sources of odor-active compounds. Volatile compounds in mango peel and seed were chemically characterized and compared with those in mango pulp using headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME/GC-MS).

Results: More than 60 volatile compounds were detected in mango by-products, whose aromatic activity was estimated using odorant activity values (OAVs).

Natural extracts from fresh and oven-dried winemaking by-products as valuable source of antioxidant compounds.

Winemaking by-products are a natural source of antioxidant components; however, due to their highly perishable and seasonal nature, they may require a prior conservation step before being processed. Natural extracts from fresh and oven-dried red grape agro-industrial by-products were obtained by ultrasound assisted extraction (UAE), using a hydroalcoholic solution as extracting solvent. Extracts were analyzed by HPLC-DAD-ESI-MS, to know the feasibility of winemaking by-products as natural sources of phenolic compounds, as well as the effect of the oven-drying treatment on the phenolic composition.

Fingerprints of acacia aging treatments by barrels or chips based on volatile profile, sensorial properties, and multivariate analysis.

Background: Despite the acceptance of the use of chips as an alternative enological practice to traditional barrels, there is substantial interest in looking for parameters that enable the aging technique to be identified. In the present study, the volatile compound composition and sensorial characteristics of wines aged with chips and barrels of acacia wood were monitored with the aim of finding fingerprints that could be used to discriminate between the two types of aging.

Results: Principal component analysis (PCA) calculated from chemical outputs permitted the two aging techniques to be distinguished.

Bioactive Flavonoids, Antioxidant Behaviour, and Cytoprotective Effects of Dried Grapefruit Peels (Citrus paradisi Macf.).

Grapefruit (Citrus paradisi Macf.) is an important cultivar of the Citrus genus which contains a number of nutrients beneficial to human health. The objective of the present study was to evaluate changes in bioactive flavonoids, antioxidant behaviour, and in vitro cytoprotective effect of processed white and pink peels after oven-drying (45°C-60°C) and freeze-drying treatments.