Polyphenols in kombucha: impact of infusion time on extraction and investigation of their behavior during “fermentation”

C-Glucosidic ellagitannins, which are the main polyphenolic compounds in oak heartwood, are extracted by wine during aging in oak barrels. Although such maturing of alcoholic beverages in oak barrels is a multi-centennial practice, very little is known on the impact of these ellagitannins on the organoleptic properties of red wine. The objectives of the present investigation were (i) to isolate oak ellagitannins and to hemisynthesize some made-in-wine flavano-ellagitannins, such as acutissimin A; (ii) to analyse their concentration ranges depending on the cultivar area and (iii) to evaluate their sensory impact on the basis of their human threshold concentrations and dose/response relationships in different types of solutions.

A seven years survey (2003 to 2009) has been carried out over old traditional vineyards cv. Cencibel in La Mancha region (Spain). Seven plots with more than 35 years old were sampled from veraison to harvest, measuring soluble solids (ºBaumé) and acid concentration (g/l in tartaric acid).

In this study, a soil mapping methodology at subplot level (scale 1:5000) for vineyard soils was developed. The aim of this mapping method was to establish mapping units, which could be used as basic units for ‘terroir’ characterisation and vineyard management (precision viticulture).

Certain grape varieties contain negligible levels of isobutyl methoxypyrazine (IBMP) in grapes. However, it has long been known that grape stems

One of the main challenges in the wine industry is to understand how different wine processing techniques and practices can influence the overall quality of the final product.