建立牛血清白蛋白-葡萄糖(BSA-Glucose)热加工模拟体系,用荧光光谱法测定激发光谱/发射光谱(λex/λem)=370nm/440nm荧光值,研究加热温度、加热时间、初始pH值、蛋白质浓度、抗氧化剂对晚期糖基化末端产物(advanced glycation end products,AGEs)形成的影响。结果表明:随着加热温度升高和加工时间延长,AGEs含量呈现先增加后减少的趋势,分别在100℃、60min时达到最大值;初始pH值对AGEs形成具有重要影响,pH7.0时产生AGEs最多,碱性条件次之,酸性条件最少;茶多酚、迷迭香酸、甘草黄酮对AGEs的生成具有显著的抑制作用;金属离子中Fe3+、Fe2+、Al3+、Zn2+和Ca2+对AGEs的形成无显著影响。因此,加工条件如加热时间、加工温度及初始pH值对BSA-Glucose模拟体系中AGEs的形成具有重要影响,且食品级天然抗氧化剂茶多酚、迷迭香酸和甘草黄酮可抑制AGEs形成,金属离子对AGEs形成无影响。
This paper reports on the results of an investigation into the effects of temperature,heating time,initial pH,protein concentration and antioxidant type on the formation of advanced glycation end products(AGEs) in a simulated thermal processing system consisting of BSA and glucose.Fluorescence intensity at an excitation/emission wavelength of 370 nm/440 nm was used as a measure of the formation of AGEs.The results showed that the production of AGEs tended to first increase to the maximum at 100 ℃ and 60 min,respectively,and then decrease with increasing temperature and prolonged heating time.Initial pH was an important variable that influences the formation of AGEs;the largest amount of AGEs were formed at pH 7.0,followed by alkaline conditions,and the formation of AGEs was minimized under acid conditions.The formation of AGEs was substantially affected by tea polyphenols,liquorice flavonoids and rosemary acid but little affected by Fe2+,Fe3+,Al3+,Zn2+ or Ca2+.Hence,the formation of AGEs is affected importantly by process conditions including heating time,temperature and initial pH,and is inhibited by tea polyphenols,liquorice flavonoids and rosemary acid as food-grade natural antioxidants but is not affected by metal ions.