Lima Adriano, Pereira José Alberto, Baraldi Ilton, Malheiro Ricardo
School of Agriculture, Polytechnic Institute of Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; Universidade Tecnológica Federal do Paraná, Campus Medianeira, Avenida Brasil, 4232, Bairro Independência, CEP 85884-000 Medianeira, Paraná, Brazil.
REQUIMTE/LAQV, School of Agriculture, Polytechnic Institute of Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal.
Food Chem. 2017 Apr 15;221:1197-1205. doi: 10.1016/j.foodchem.2016.11.039. Epub 2016 Nov 9.
Grapevine leaves (Vitis vinifera L. var. Malvasia Fina and Touriga Franca) under culinary treatment (blanching and boiling at 60, 75 and 90min) were studied for their color, pigments and volatile fraction changes. Blanching and boiling caused a decrease in luminosity and a loss of green coloration in both varieties, while a yellow-brownish color arose. Significant correlations were established between the loss of green color (monochromatic variable a) and the total chlorophylls content. The main volatiles in fresh leaves [(Z)-3-hexenal, (Z)-3-hexen-1-ol, and (Z)-3-hexenyl acetate] were drastically reduced by blanching and suppressed by boiling. Other compounds like pentanal and 6-methyl-5-hepten-2 one arose from blanching and boiling. A boiling time of 60min is adequate for the culinary process of grapevine leaves, since the product is considered edible and the pigments and volatile changes are not as drastic as observed at 75 and 90min of boiling.
对烹饪处理（在60、75和90分钟进行焯烫和水煮）后的葡萄叶（酿酒葡萄品种马尔瓦西亚菲娜和弗朗卡杜丽佳）的颜色、色素和挥发性成分变化进行了研究。焯烫和水煮导致两个品种的葡萄叶亮度降低和绿色褪去，同时呈现出黄棕色。绿色的损失（单色变量a）与总叶绿素含量之间建立了显著的相关性。鲜叶中的主要挥发性成分[（Z）-3-己烯醛、（Z）-3-己烯-1-醇和（Z）-3-己烯基乙酸酯]在焯烫时大幅减少，在水煮时被抑制。其他化合物如戊醛和6-甲基-5-庚烯-2-酮则因焯烫和水煮而产生。对于葡萄叶的烹饪过程，60分钟的水煮时间就足够了，因为此时产品被认为是可食用的，而且色素和挥发性成分的变化不像水煮75分钟和90分钟时那么剧烈。
