As a non-thermal processing technology,high hydrostatic pressure(HHP)can be used for starch modification without affecting the quality and flavour constituents.The effect of HHP on starch is closely related to the tre...As a non-thermal processing technology,high hydrostatic pressure(HHP)can be used for starch modification without affecting the quality and flavour constituents.The effect of HHP on starch is closely related to the treatment time of HHP.In this paper,we investigated the impacts of HHP treatment time(0,5,10,15,20,25,30 min)on the microstructure,gelatinization and thermal properties as well as in vitro digestibility of oat starch by scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,13C NMR and differential scanning calorimeter.Results showed that 5-min HHP treatment led to deformation and decreases in short-range ordered and doublehelix structures of oat starch granules,and further extending the treatment time to 15 min or above caused the formation of a gelatinous connection zone,increase of particle size,disintegration of short-range ordered and double-helix structures,and crystal structure change from A type to V type,indicating gelatinization occurred.Longer treatment time also resulted in the reduction in both the viscosity and the stability of oat starch.These indicated that HHP treatment time greatly influenced the microstructure of oat starch,and the oat starch experienced crystalline destruction(5 min),crystalline disintegration(15 min)and gelatinization(>15 min)during HHP treatment.Results of in vitro digestibility showed that the rapidly digestible starch(RDS)content declined first after treatment for 5 to 10 min then rose with the time extending from 15 to 30 min,indicating that longer pressure treatment time was unfavourable to the health benefits of oat starch for humans with diabetes and cardiovascular disease.Therefore,the 500-MPa treatment time for oat starch is recommended not more than 15 min.This study provides theoretical guidance for the application of HHP technology in starch modification and development of health foods.展开更多
Starch is the major carbohydrate in oat （Avena sativa L.） and starch formation requires the coordinated actions of several synthesis enzymes. In this study, the granule morphology, composition and physicochemical pr...Starch is the major carbohydrate in oat （Avena sativa L.） and starch formation requires the coordinated actions of several synthesis enzymes. In this study, the granule morphology, composition and physicochemical properties of oat starch, as well as the expressions of starch synthesis genes were investigated during oat endosperm development. Under the scanning electron microscopy （SEM）, we observed that the unique compound granules were developed in oat endosperms at 10 days post anthesis （DPA） and then fragmented into irregular or polygonal simple granules from 12 DPA until seed maturity. The amylose content, branch chain length of degree of polymerization （DP=13-24）, gelatinization temperature and percentage of retrogradation were gradually increased during the endosperm development; whereas the distribution of short chains （DP=6-12） were gradually decreased. The relative expressions of 4 classes of 13 starch synthesis genes characterized in this study indicated that three expression pattern groups were significantly different among gene classes as well as among varied isoforms, in which the first group of starch synthesis genes may play a key role on the initiation of starch synthesis in oat endosperms.展开更多
在单因素试验的基础上,利用Box-Benhnken中心组合试验和响应面分析法优化莜麦淀粉提取工艺条件,并检测了其理化性质。结果表明:莜麦淀粉最佳提取工艺参数为料液比1∶11.59,提取温度48.84℃,提取时间137.31 min,p H 8.73,该条件下莜麦淀...在单因素试验的基础上,利用Box-Benhnken中心组合试验和响应面分析法优化莜麦淀粉提取工艺条件,并检测了其理化性质。结果表明:莜麦淀粉最佳提取工艺参数为料液比1∶11.59,提取温度48.84℃,提取时间137.31 min,p H 8.73,该条件下莜麦淀粉的提取率为75.58%。与对照组比,莜麦淀粉溶解度较小,糊化温度较高,莜麦淀粉糊冻融稳定性、热糊稳定性和冷糊稳定性均较差,易发生老化。展开更多
基金supported financially by the National Natural Science Foundation of China (Grant No.31760468 and32060515)Inner Mongolia Autonomous Region Science and Technology Plan Project (No.2020GG0064)
文摘As a non-thermal processing technology,high hydrostatic pressure(HHP)can be used for starch modification without affecting the quality and flavour constituents.The effect of HHP on starch is closely related to the treatment time of HHP.In this paper,we investigated the impacts of HHP treatment time(0,5,10,15,20,25,30 min)on the microstructure,gelatinization and thermal properties as well as in vitro digestibility of oat starch by scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,13C NMR and differential scanning calorimeter.Results showed that 5-min HHP treatment led to deformation and decreases in short-range ordered and doublehelix structures of oat starch granules,and further extending the treatment time to 15 min or above caused the formation of a gelatinous connection zone,increase of particle size,disintegration of short-range ordered and double-helix structures,and crystal structure change from A type to V type,indicating gelatinization occurred.Longer treatment time also resulted in the reduction in both the viscosity and the stability of oat starch.These indicated that HHP treatment time greatly influenced the microstructure of oat starch,and the oat starch experienced crystalline destruction(5 min),crystalline disintegration(15 min)and gelatinization(>15 min)during HHP treatment.Results of in vitro digestibility showed that the rapidly digestible starch(RDS)content declined first after treatment for 5 to 10 min then rose with the time extending from 15 to 30 min,indicating that longer pressure treatment time was unfavourable to the health benefits of oat starch for humans with diabetes and cardiovascular disease.Therefore,the 500-MPa treatment time for oat starch is recommended not more than 15 min.This study provides theoretical guidance for the application of HHP technology in starch modification and development of health foods.
基金supported by the National Natural Science Foundation of China (31230053)the Ministry of Education (MOE) of China and Agriculture and Agri-Food Canada (AAFC) Ph D Research Program
文摘Starch is the major carbohydrate in oat （Avena sativa L.） and starch formation requires the coordinated actions of several synthesis enzymes. In this study, the granule morphology, composition and physicochemical properties of oat starch, as well as the expressions of starch synthesis genes were investigated during oat endosperm development. Under the scanning electron microscopy （SEM）, we observed that the unique compound granules were developed in oat endosperms at 10 days post anthesis （DPA） and then fragmented into irregular or polygonal simple granules from 12 DPA until seed maturity. The amylose content, branch chain length of degree of polymerization （DP=13-24）, gelatinization temperature and percentage of retrogradation were gradually increased during the endosperm development; whereas the distribution of short chains （DP=6-12） were gradually decreased. The relative expressions of 4 classes of 13 starch synthesis genes characterized in this study indicated that three expression pattern groups were significantly different among gene classes as well as among varied isoforms, in which the first group of starch synthesis genes may play a key role on the initiation of starch synthesis in oat endosperms.
文摘在单因素试验的基础上,利用Box-Benhnken中心组合试验和响应面分析法优化莜麦淀粉提取工艺条件,并检测了其理化性质。结果表明:莜麦淀粉最佳提取工艺参数为料液比1∶11.59,提取温度48.84℃,提取时间137.31 min,p H 8.73,该条件下莜麦淀粉的提取率为75.58%。与对照组比,莜麦淀粉溶解度较小,糊化温度较高,莜麦淀粉糊冻融稳定性、热糊稳定性和冷糊稳定性均较差,易发生老化。
文摘以燕麦粉为原料,采用稀碱法从中提取淀粉,结合响应面法分析燕麦淀粉提取最佳条件,结果表明在pH值为10.4,液固比为6.7,时间为2.9 h时,淀粉中蛋白质残留最低,为1.19%,淀粉得率63.38%。经加中性蛋白酶处理后能有效地降低燕麦淀粉中残留蛋白质的含量,加酶量48 AU/kg,温度50℃,液固比6,pH值为7.0,时间60 m in时,燕麦淀粉中蛋白质的残留量可降为0.6%左右,淀粉得率60.26%。
