McRae Jacqui M, Falconer Robert J, Kennedy James A
The Australian Wine Research Institute, PO Box 197, Glen Osmond SA 5064, Australia.
J Agric Food Chem. 2010 Dec 8;58(23):12510-8. doi: 10.1021/jf1030967. Epub 2010 Nov 11.
The astringency of red wine is largely due to the interaction between wine tannins and salivary proline-rich proteins and is known to change as wine ages. To further understand the mechanisms behind wine astringency change over time, thermodynamics of the interactions between poly(l-proline) (PLP) and grape seed and skin tannins (preveraison (PV) and commercially ripe) or Shiraz wine tannins (2 years old and 9-10 years old) was analyzed using isothermal titration calorimetry (ITC). The nature of these interactions varied with changes to the tannin structure that are associated with maturation. The change in enthalpy associated with hydrophobic interaction and hydrogen bonding decreased with tannin age and the stoichiometry of binding indicated that grape tannins associated with more proline residues than wine tannins, irrespective of molecular size. These results could provide an explanation for the observed change in wine astringency quality with age.
红葡萄酒的涩味很大程度上归因于葡萄酒中单宁与富含脯氨酸的唾液蛋白之间的相互作用，并且已知其会随着葡萄酒的陈酿而变化。为了进一步了解葡萄酒涩味随时间变化的背后机制，使用等温滴定量热法（ITC）分析了聚（L-脯氨酸）（PLP）与葡萄籽和葡萄皮单宁（转色前（PV）和商业成熟）或设拉子葡萄酒单宁（2年和9 - 10年）之间相互作用的热力学。这些相互作用的性质随与成熟相关的单宁结构变化而变化。与疏水相互作用和氢键相关的焓变随着单宁陈酿时间的增加而降低，并且结合化学计量表明，无论分子大小如何，葡萄单宁比葡萄酒单宁与更多的脯氨酸残基结合。这些结果可以解释观察到的葡萄酒涩味品质随陈酿时间的变化。
