摘要
秋葵中富含黏性多糖类成分。本文研究干燥方式对秋葵多糖结构特征和抗氧化性能的影响。将秋葵原料分别用热风干燥、自然干燥和真空冷冻干燥处理,用水提醇沉法制备获得水溶性多糖,然后对其基本理化性质、单糖组成、红外光谱、黏度和抗氧化性进行比较分析。结果显示:3种多糖主要由I型鼠李糖半乳糖醛酸(RG-I)果胶组成,具有不同的线性程度。3种多糖红外图谱相似,固体形貌具有一定差异,分子质量分布也有一定差异性。通过测定其表观黏度,发现3种多糖在一定质量分数下均具有弱凝胶性质,其中热风干燥处理的秋葵所提取的多糖黏度最大。此外,3种多糖均具有一定的清除DPPH自由基、羟自由基以及螯合金属离子的能力,其中自然干燥处理的秋葵多糖的体外抗氧化能力最强。上述3种干燥方法所得秋葵多糖各有特点,可根据多糖的用途来决定秋葵干燥方式。
Okra is rich in viscous polysaccharide.This paper intended to study the effects of different drying methods on the structure and antioxidant properties of okra polysaccharide.After the okra raw material dried by hot air,natural drying and vacuum freeze-drying,the water-soluble polysaccharide was prepared by water extraction and alcohol precipitation method.Then,the basic physicochemical properties,monosaccharide composition,infrared spectrum,viscosity and antioxidant properties of okra were compared and analyzed.The results showed that the three polysaccharides were mainly composed of type I rhamnogalacturonan(RG-I)pectin,but with different linearity.Infrared spectra of the three polysaccharides were similar,while the solid morphology and molecular weight distribution were different to some extent.By measuring the apparent viscosity,it was found that the three polysaccharides had weak gel properties at a certain mass fraction,among which the polysaccharide viscosity was the highest in okra dried by hot air.In addition,the three polysaccharides all had certain ability of scavenging DPPH free radical,hydroxyl free radical and chelating metal ion,among which the antioxidant ability of okra polysaccharide was the strongest after natural drying treatment in vitro.In conclusion,the polysaccharides obtained from okra through the above three drying methods have their own characteristics,and the final drying method of okra can be determined according to the purpose of the final polysaccharide.
作者
王喆
马璐瑶
林海峰
聂少平
殷军艺
Wang Zhe;Ma Luyao;Lin Haifeng;Nie Shaoping;Yin Junyi(State Key Laboratory of Food Science and Technology,Nanchang University,Nanchang 330047)
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2022年第2期310-318,共9页
Journal of Chinese Institute Of Food Science and Technology
基金
“十三五”国家重点研发计划重点专项(2017YFD0400104)
国家自然科学基金面上项目(31871775)。
关键词
秋葵
多糖
干燥方式
结构特征
抗氧化
okra
polysaccharide
drying method
structural characteristics
antioxidant
