Oat milk has gained widespread consumer acceptance for its creamy texture,β-glucan content,and environmental sustainability.However,its relatively low protein content(typically 2-3 g/serving)presents a nutritional li...Oat milk has gained widespread consumer acceptance for its creamy texture,β-glucan content,and environmental sustainability.However,its relatively low protein content(typically 2-3 g/serving)presents a nutritional limitation,largely due to poor protein solubility.This study investigated how processing conditions influence protein content and functional stability in oat-based systems by applying two treatments:(1)α-amylase enzymatic hydrolysis,and(2)pH-shifting(from pH 7 to 12 and back)with mild heating(50℃for 10 or 30 min).Oat protein solutions were formulated from two sources:oat flour(OF)and oat protein isolate(OPI).Results suggests that α-amylase pretreatment effectively reduced starch-driven viscosity in OF,facilitating better sample handling and centrifugation.Following pH-shifting and heat treatment,both OF and OPI solutions showed significantly improved protein solubility,with protein content increased from 2.0 to~6.5 g/serving.These changes were accompanied by reduced precipitation,smaller particle sizes,and more negative zeta potential values,indicating enhanced colloidal stability.SDS-PAGE analysis revealed the presence of low-molecular-weight protein fractions,supporting increased solubilization.Fluorescence microscopy confirmed the formation of smaller,more uniformly dispersed particles in treated samples compared to controls.However,noticeable darkening or browning occurred under high-pH heating,indicating potential challenges in color control.The findings provide useful information for future industrial applications and product innovation in the plant-based beverage sector.展开更多
The application of potato protein(PP)in food industry has been limited due to its low water solubility,poor emulsification and stability.Herein,it was found that the pH-shifting combined with microwave heating signifi...The application of potato protein(PP)in food industry has been limited due to its low water solubility,poor emulsification and stability.Herein,it was found that the pH-shifting combined with microwave heating significantly increased the solubility of PP(from 24.0%to 89.0%)and surface hydrophobicity(from 125 to 207).The particle size of PP was significantly reduced(from 249.95±1.15 mm to 90.37±1.03 nm).SDS-PAGE analysis indicated that the microwave treatment did not disrupt the primary structure of PP.A complex formation between modified potato protein(MPP)and pectin(PC)at the optimum mass ratio of MPP to PC of 4:1 and pH 5 was characterized by fluorescence spectroscopy,fourier transform infrared spectroscopy,scanning electron microscopy and transmission electron microscopy,which showed that MPP and PC had electrostatic interaction.Moreover,the effect of mass ratios of MPP to PC from 5:1 to 1:2 on the phase behavior of MPP-PC soluble complexes was evaluated by the phase diagram andζ-potential measurement.These results showed that the dispersibility,emulsification and thermal stability of the protein were improved by forming MPP-PC complexes.This study provides a valuable reference for the improvement of physicochemical and functional properties of PP which is conducive to broaden the application of the protein in food industry.展开更多
大豆分离蛋白(soybean protein isolate,SPI)是食品工业中一种重要的植物蛋白。然而,其致密的球形聚集结构导致分子柔韧性降低,严重影响了其功能特性。因此,本文采用脉冲电场(pulsed electric field,PEF)和pH偏移技术对SPI进行改性处理...大豆分离蛋白(soybean protein isolate,SPI)是食品工业中一种重要的植物蛋白。然而,其致密的球形聚集结构导致分子柔韧性降低,严重影响了其功能特性。因此,本文采用脉冲电场(pulsed electric field,PEF)和pH偏移技术对SPI进行改性处理,研究了脉冲电场和pH偏移的三种不同组合处理方式(先PEF后pH偏移、先pH偏移后PEF、PEF联合pH偏移)对SPI结构和功能特性的影响。结果表明:三种方法中,PEF联合pH偏移处理对SPI聚集结构的影响最为明显,处理后的SPI具有最高的溶解度(90.23%)、最小的浊度(0.074)、最大绝对ζ-电位值(44.4 mV)和最小的颗粒大小(63.5 nm)。PEF联合pH偏移处理能够诱导SPI二三级部分的解折叠,使得球状堆积态的SPI转换为“熔球态”,并具有更低含量的α-螺旋和β-折叠,以及更高含量的无规卷曲,蛋白结构整体呈现松散和无序状。经不同方法改性后的SPI均表现出更好的功能特性,对SPI功能特性的改善效果排序如下:PEF联合pH偏移>先pH偏移后PEF>先PEF后pH偏移。与未处理组相比,PEF联合pH偏移得到的SPI的乳化性(EAI)、乳化稳定性(ESI)、起泡活性(FA)和与叶黄素的结合常数分别提高了119.24%、39.33%、59.03%和245.81%。综上,采用脉冲电场和pH偏移的不同组合处理能够显著影响SPI的结构和功能特性,其中PEF联合pH偏移处理能诱导SPI高级结构的更大程度的展开,改善其功能特性。展开更多
基金supported by the USDA National Institute of Food and Agriculture,Hatch project 7009323.
文摘Oat milk has gained widespread consumer acceptance for its creamy texture,β-glucan content,and environmental sustainability.However,its relatively low protein content(typically 2-3 g/serving)presents a nutritional limitation,largely due to poor protein solubility.This study investigated how processing conditions influence protein content and functional stability in oat-based systems by applying two treatments:(1)α-amylase enzymatic hydrolysis,and(2)pH-shifting(from pH 7 to 12 and back)with mild heating(50℃for 10 or 30 min).Oat protein solutions were formulated from two sources:oat flour(OF)and oat protein isolate(OPI).Results suggests that α-amylase pretreatment effectively reduced starch-driven viscosity in OF,facilitating better sample handling and centrifugation.Following pH-shifting and heat treatment,both OF and OPI solutions showed significantly improved protein solubility,with protein content increased from 2.0 to~6.5 g/serving.These changes were accompanied by reduced precipitation,smaller particle sizes,and more negative zeta potential values,indicating enhanced colloidal stability.SDS-PAGE analysis revealed the presence of low-molecular-weight protein fractions,supporting increased solubilization.Fluorescence microscopy confirmed the formation of smaller,more uniformly dispersed particles in treated samples compared to controls.However,noticeable darkening or browning occurred under high-pH heating,indicating potential challenges in color control.The findings provide useful information for future industrial applications and product innovation in the plant-based beverage sector.
基金the National Natural Science Foundation of China(No.22078143)Jiangxi Provincial Finance Science and Technology Special"Contract System"Demonstration Project(No.ZBG20230418035)the Research Project of State Key Laboratory of Food Science and Resources,Nanchang University(No.SKLF-ZZB-202331)for financial support.
文摘The application of potato protein(PP)in food industry has been limited due to its low water solubility,poor emulsification and stability.Herein,it was found that the pH-shifting combined with microwave heating significantly increased the solubility of PP(from 24.0%to 89.0%)and surface hydrophobicity(from 125 to 207).The particle size of PP was significantly reduced(from 249.95±1.15 mm to 90.37±1.03 nm).SDS-PAGE analysis indicated that the microwave treatment did not disrupt the primary structure of PP.A complex formation between modified potato protein(MPP)and pectin(PC)at the optimum mass ratio of MPP to PC of 4:1 and pH 5 was characterized by fluorescence spectroscopy,fourier transform infrared spectroscopy,scanning electron microscopy and transmission electron microscopy,which showed that MPP and PC had electrostatic interaction.Moreover,the effect of mass ratios of MPP to PC from 5:1 to 1:2 on the phase behavior of MPP-PC soluble complexes was evaluated by the phase diagram andζ-potential measurement.These results showed that the dispersibility,emulsification and thermal stability of the protein were improved by forming MPP-PC complexes.This study provides a valuable reference for the improvement of physicochemical and functional properties of PP which is conducive to broaden the application of the protein in food industry.
文摘大豆分离蛋白(soybean protein isolate,SPI)是食品工业中一种重要的植物蛋白。然而,其致密的球形聚集结构导致分子柔韧性降低,严重影响了其功能特性。因此,本文采用脉冲电场(pulsed electric field,PEF)和pH偏移技术对SPI进行改性处理,研究了脉冲电场和pH偏移的三种不同组合处理方式(先PEF后pH偏移、先pH偏移后PEF、PEF联合pH偏移)对SPI结构和功能特性的影响。结果表明:三种方法中,PEF联合pH偏移处理对SPI聚集结构的影响最为明显,处理后的SPI具有最高的溶解度(90.23%)、最小的浊度(0.074)、最大绝对ζ-电位值(44.4 mV)和最小的颗粒大小(63.5 nm)。PEF联合pH偏移处理能够诱导SPI二三级部分的解折叠,使得球状堆积态的SPI转换为“熔球态”,并具有更低含量的α-螺旋和β-折叠,以及更高含量的无规卷曲,蛋白结构整体呈现松散和无序状。经不同方法改性后的SPI均表现出更好的功能特性,对SPI功能特性的改善效果排序如下:PEF联合pH偏移>先pH偏移后PEF>先PEF后pH偏移。与未处理组相比,PEF联合pH偏移得到的SPI的乳化性(EAI)、乳化稳定性(ESI)、起泡活性(FA)和与叶黄素的结合常数分别提高了119.24%、39.33%、59.03%和245.81%。综上,采用脉冲电场和pH偏移的不同组合处理能够显著影响SPI的结构和功能特性,其中PEF联合pH偏移处理能诱导SPI高级结构的更大程度的展开,改善其功能特性。
