【摘要】 分析了单宁对增加杨梅汁花色苷稳定性的效果 .在 p H=4 .5和 p H=3.2时加入单宁使杨梅汁最大吸收波长和最大吸光度增大 .在 p H为 1.0时单宁浓度增大导致杨梅汁最大吸收波长增大 ,但最大吸光度没有增加 .单宁和杨梅汁花色苷的辅助色素反应为放热反应 ,其ΔH等于- 8.4 81k J/ mol,Δ S为 7.2 86 J/ mol.温度的升高促进辅助色素反应向分解方向进行更多还原

【Abstract】 The effect of tannin on the stability of anthocyanin in Yangmei ( Myrica rubra )juice is rather significant.In the Yangmei juice at pH1.0,pH3.2 and pH4.5, the Cy 3 Gl and tannin copigmentation consist in an increase in the visible band intensity (except at pH 1.0)and in a shift of band toward longer wavelengths. At pH3.2, the Cy 3 Gl and tannin copigmentation is a exothemic process.The change in enthalpy(Δ H )and entropy (Δ S ) is 8.481 kJ/mol and 7.286 J/mol,respectively.更多还原