Grape quality assessment

Day, R.E. (1981) Juice preparation procedures. Proc. Grape Quality Assessment from vineyard to juice preparation. Aust. Soc. Vitic. Oenol. Adelaide, pp. 57-65. 

Monagas, M., Hemandez-Ledesma, B., Garrido, I., Martm-Alvarez, P.J., Gomez-Cordoves, C., Bartolome, B. (2005). Quality assessment of commercial dietary antioxidant products from Vitis vinifera L. grape seeds. Nutr. Cancer, 53, 244-254. 

Table 20.13 provides data on the average composition of grape musts. For the quality assessment of grape must, its relative density at 20 °C is decisive. This is measured with a special aerometer (must balance). The must weight M, expressed in Oechsle degrees, is directly read off. 

The grape spirits permitted are subjected to rigorous quality standards, performed by the laboratories and tasters panel of the IVDP. Turbidity, color, aroma, and taste are evaluated. Ethyl carbamate, total higher alcohols, acetaldehyde, ethyl acetate, methanol, 2-butanol, 1-buta-nol, allylic acid, and cyanidric acid concentrations are analyzed calcium, copper, and iron contents determined and the alcohol content, total acidity, and density assessed. All must be below designated limits (Regulamento n° 84/2010). 

Vltlcultural aspects. Vitlcultural research would benefit from detailed investigations concerning influences of major preharvest variables on monoterpene composition of fruit. Different pruning techniques, trellis designs, soil characteristics and climatic variables have yet to be assessed for their impact on grape flavorants. Research has been carried out on some of these factors in relation to wine quality (92,93) and now their effect on fruit... 

Villani, T.S., Reichert, W., Ferruzzi, M.G., Pasinetti, G.M., Simon, J.E., and Wn, Q.L. 2015. Chemical investigation of commercial grape seed derived products to assess quality and detect adulteration. Food Chem., 170 271-280. 

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