The dose-response effect on polyphenol bioavailability after intake of white and red wine pomace products by Wistar rats.

Wine pomace by-products are an important source of phenolic acids with significant health benefits. However, phenolic acid bioavailability in vivo has been little studied and there are few comparative studies on bioavailability between red and white wine pomace and the effect of intake of different doses. The qualitative and quantitative profile of phenolic acid metabolites in plasma and urine samples from Wistar rats was obtained by gas chromatography/mass detection, after oral administration of four doses (50, 100, 150, and 300 mg) of both the red and the white wine pomace products (rWPP and wWPP, respectively). The antioxidant capacity of the plasma samples assessed by both the ABTS and the FRAP levels was also evaluated. The results showed that neither the bioavailability nor the antioxidant capacity in vivo of the rWPP increased at high doses. However, both parameters were dependent on the intake of the wWPP.

Application of the Just-About-Right Scales in the Development of New Healthy Whole-Wheat Muffins by the Addition of a Product Obtained from White and Red Grape Pomace.

The aim of this study was to evaluate the adequacy of sensory attributes, by the use of just-about-right (JAR) scales and penalty analysis, of new healthy whole-wheat muffins with high fibre content due to the addition of two products obtained from white and red grape pomace. Furthermore, the nutritional, colour and texture properties of the muffins were evaluated. For that, five formulations of whole-wheat muffins were studied: a control muffin made with 100% whole-wheat flour and muffins made with 10 and 20% of white and red grape pomace product, respectively. The incorporation of grape pomace products in the recipe led to muffins with "high-fibre content", which would imply healthy properties in these muffins. The hardness and chewiness increased whereas the springiness, cohesiveness, resilience and colour parameters decreased when the grape pomace products were incorporated. The sensory analysis indicated high levels of acceptability of the muffins that incorporated white and red grape pomace products at concentrations of 10%. The penalty analysis showed that none of the attributes evaluated affected the acceptability of the new muffins significantly; only the darker colour of the muffins caused by the red grape pomace product could affect the acceptability, although this fact was not clearly demonstrated.

Applications of Wine Pomace in the Food Industry: Approaches and Functions.

Winemaking generates large amounts of wine pomace, also called grape pomace. This by-product has attracted the attention of food scientists and the food industry, due to its high content in nutrients and bioactive compounds. This review mainly focuses on the different published approaches to the use of wine pomace and its functions in the food industry. Traditionally, wine pomace has been used to obtain wine alcohol, food colorings, and grape seed oil. More recently, research has focused in the production of other value-added products, such as extracts of bioactive compounds, mainly phenols, recovery of tartaric acid, and the making of flours. The most common functions associated with wine pomace products are their use as antioxidants, followed by their use as fortifying, coloring, and antimicrobial agents. These products have mainly been applied to the preparation of meat and fish products and to, a lesser extent, cereal products.

Wine consumption habits and consumer preferences between wines aged in barrels or with chips.

BACKGROUND: The use of oak wood pieces in winemaking is increasing, but the acceptance of this technique by consumers is unknown. For that reason, the main aim of this study was to measure consumers' opinion of red wines made with this new technique, their acceptance of them and their intention to purchase these wines. A preference ranking test was also carried out. RESULTS: A specific questionnaire was drawn up for this study and 65 frequent red wine consumers tasted four wines, two aged traditionally in barrels and two macerated with chips, and a forced choice preference test was carried out. Fifty-five per cent of respondents said that they would not buy wines made using oak chips, although most respondents would buy these wines if, after tasting them, they were as pleasant and had the same quality as the wines aged traditionally in barrels. CONCLUSION: Wines obtained with oak wood fragments were not significantly rejected either by consumers who answered the questionnaire or by consumer tasters, which could be due to the large disparity of preferences found among tasters. The results clearly indicate that producers should develop each wine taking into account the specific preferences of each consumer group.

alpha-Tocopherol, MDA-HNE and 8-OHdG levels in liver and heart mitochondria of adriamycin-treated rats fed with alcohol-free beer.

Different studies indicate that oxidative stress and mitochondrial damage are key factors in different pathogenic process. The aim of this study was to investigate the possible protective role of alcohol-free beer on adriamycin-induced (ADR) heart and liver toxicity using biomarkers of oxidative stress. This effect was compared with the effect of alcohol beer intake and with a control group. Rats were randomly divided into six groups. The first group received no adriamycin, was fed with water and was regarded as the control group; the second group was injected with a ADR (two cycles of 5mg/kg); the third and fourth groups were fed with alcohol-free and beer for 21 days, respectively and the fifth and sixth groups were fed with alcohol-free and beer beginning 7 days before the administration of a first dose of ADR. Beer was administrated intragastrically and ADR (two cycles of 5mg/kg) was intraperitoneally. The levels of MDA+4HNE (malondialdehyde and 4-hydroxynonenal) in heart mitochondria was higher in the group treated with ADR alone than in the control groups, and it was lower in the groups treated with ADR that drank beer than in the ADR group alone. However, no difference was observed in liver mitochondria between the group treated with ADR and the group treated with ADR that drank beer. Significant decrease in the levels of heart and liver alpha-tocopherol was observed in the ADR group when compared to the control groups, and this decrease was normalized by beer treatment. Interestingly, the levels of antioxidant alpha-tocopherol in liver were significantly higher in rats that consumed alcohol-free beer than in those that consumed alcohol beer. Intake of alcohol-free beer showed a DNA protective effect to decreases significantly the levels of 8-OHdG levels in heart and liver increased by the ADR-treatment. In conclusion, this study clearly indicated that alcohol-free beer consumption significantly reduces the adriamycin-induced oxidative stress.

Multivariate evaluation of changes induced in red wine characteristics by the use of extracting agents.

The aim of the present work was to study the effect of both vintage and the use of four types of pectinolytic enzymatic preparations on the quality of red wine using factor analysis. We also studied the evolution of the factors obtained along two years of storage of the wine. The results obtained from the factor analysis revealed that the addition of pectinolytic enzymes enriched the phenolic composition and elicited an improvement in the visual aspect of the wine, which persisted during the storage period considered.