该研究利用豌豆蛋白(pea protein isolate, PPI)与γ-聚谷氨酸(γ-polyglutamic acid, γ-PGA)静电作用形成可溶性复合物,改善PPI在酸性环境下的稳定性。通过浊度、Zeta电位、相图、微观结构对可溶性复合物形成的影响因素(pH、复合比例r、蛋白浓度)进行研究,以确定其形成条件,并对该条件下的蛋白溶解度、表面疏水性、乳化活性、乳化稳定性进行测定。结果表明,复合物的形成增大了体系的静电斥力,提高了PPI在酸性环境中的稳定性。在pH 4.5、高蛋白浓度(10.0 g/L)的条件下,质量复合比为1和2的体系形成了可溶性复合物,蛋白的溶解度和表面疏水性均显著增大(P<0.05),当质量复合比为1时,体系的乳化活性与乳化稳定性最好。
In this study, pea protein isolate (PPI) and γ-polyglutamic acid (γ -PGA) were used to form a soluble complex through electrostatic interaction to improve the stability of pea protein in an acidic environment. Turbidity, Zeta potential, phase diagram and microstructure were used to study the factors affecting the formation of the soluble complex (pH, mixing ratio r, protein concentration), and to determine the conditions for the formation of the complex. The protein solubility, surface hydrophobicity, emulsifying activity, and emulsifying stability were measured under this condition. The results showed that the formation of the complex increased the electrostatic repulsion of the system, and improved the stability of PPI in an acidic environment. At pH 4.5 and high protein concentration (10.0 g/L), a soluble complex was formed in the r=1 and r=2 systems, and the protein solubility and surface hydrophobicity were significantly increased (P<0.05). When r=1, the emulsifying activity and stability of the system were the best.
[1] ADEBIYI A P, ALUKO R E.Functional properties of protein fractions obtained from commercial yellow field pea (Pisum sativum L.) seed protein isolate[J].Food Chemistry, 2011, 128(4):902-908.
[2] LIANG H N, TANG C H.pH-dependent emulsifying properties of pea[Pisum sativum (L.)] proteins[J].Food Hydrocolloids, 2013, 33(2):309-319.
[3] ALUKO R E, MOFOLASAYO O A, WATTS B M.Emulsifying and foaming properties of commercial yellow pea (Pisum sativum L.) seed flours[J].Journal of Agricultural and Food Chemistry, 2009, 57(20):9 793-9 800.
[4] TUINIER R, ROLIN C, DE KRUIF C G.Electrosorption of pectin onto casein micelles[J].Biomacromolecules, 2002, 3(3):632-638.
[5] LIN D Q, LU W, KELLY A L,et al.Interactions of vegetable proteins with other polymers:Structure-function relationships and applications in the food industry[J].Trends in Food Science & Technology, 2017, 68:130-144.
[6] LAN Y, CHEN B C, RAO J J.Pea protein isolate-high methoxyl pectin soluble complexes for improving pea protein functionality:Effect of pH, biopolymer ratio and concentrations[J].Food Hydrocolloids, 2018, 80:245-253.
[7] LIU S, ELMER C, LOW N H, et al.Effect of pH on the functional behaviour of pea protein isolate-gum Arabic complexes[J].Food Research International, 2010, 43(2):489-495.
[8] WAGONER T B, FOEGEDING E A.Whey protein-pectin soluble complexes for beverage applications[J].Food Hydrocolloids, 2017, 63:130-138.
[9] PARK J H, CHOI J C, SUNG M H, et al.High molecular weight poly-gamma-glutamic acid regulates lipid metabolism in rats fed a high-fat diet and humans[J].Journal of Microbiology and Biotechnology, 2011, 21(7):766-775.
[10] KHALIL I R, IRORERE V U, RADECKA I, et al.Poly-γ-glutamic acid:Biodegradable polymer for potential protection of beneficial viruses[J].Materials (Basel, Switzerland), 2016, 9(1):28.
[11] 齐蕾, 仵心军, 徐超, 等.γ-聚谷氨酸对大豆分离蛋白热稳定性的影响[J].中国粮油学报, 2021, 36(3):41-45.
QI L, WU X J, XU C, et al.Effect of γ-polyglutamic acid on thermal stability of soybean protein isolate[J].Journal of the Chinese Cereals and Oils Association, 2021, 36(3):41-45.
[12] STONE A K, KARALASH A, TYLER R T, et al.Functional attributes of pea protein isolates prepared using different extraction methods and cultivars[J].Food Research International, 2015, 76:31-38.
[13] MU L X, ZHAO M M, YANG B, et al.Effect of ultrasonic treatment on the graft reaction between soy protein isolate and gum Acacia and on the physicochemical properties of conjugates[J].Journal of Agricultural and Food Chemistry, 2010, 58(7):4 494-4 499.
[14] ZHU Z B, ZHU W D, YI J H, et al.Effects of sonication on the physicochemical and functional properties of walnut protein isolate[J].Food Research International, 2018, 106:853-861.
[15] HASKARD C A, LI-CHAN E C Y.Hydrophobicity of bovine serum albumin and ovalbumin determined using uncharged (PRODAN) and anionic (ANS-) fluorescent probes[J].Journal of Agricultural and Food Chemistry, 1998, 46(7):2 671-2 677.
[16] ARYEE F N A, NICKERSON M T.Formation of electrostatic complexes involving mixtures of lentil protein isolates and gum Arabic polysaccharides[J].Food Research International, 2012, 48(2):520-527.
[17] NIU F G, SU Y J, LIU Y T, et al.Ovalbumin-gum Arabic interactions:Effect of pH, temperature, salt, biopolymers ratio and total concentration[J].Colloids and Surfaces B:Biointerfaces, 2014, 113:477-482.
[18] LIU S H, LOW N H, NICKERSON M T.Effect of pH, salt, and biopolymer ratio on the formation of pea protein isolate-gum Arabic complexes[J].Journal of Agricultural and Food Chemistry, 2009, 57(4):1 521-1 526.
[19] AZARIKIA F, ABBASI S.Mechanism of soluble complex formation of milk proteins with native gums (tragacanth and Persian gum)[J].Food Hydrocolloids, 2016, 59:35-44.
[20] 樊雪静, 刘红玉, 迟玉杰.大豆分离蛋白与寡糖静电相互作用及复合物乳化性的分析[J].食品科学,2018,39(12):126-132.
FAN X J, LIU H Y, CHI Y J.Electrostatic interaction of soybean protein isolate with oligosaccharide and emulsifying capacity of their complexes[J].Food Science, 2018, 39(12):126-132.
[21] LOPES-DA-SILVA J A, MONTEIRO S R.Gelling and emulsifying properties of soy protein hydrolysates in the presence of a neutral polysaccharide[J].Food Chemistry, 2019, 294:216-223.
[22] 庞淑婕, 李娜娜, 任思, 等.豌豆分离蛋白-羧甲基纤维素纳静电复合物在乳液中的应用研究[J].食品工业科技, 2020, 41(21):75-80.
PANG S J, LI N N, REN S, et al.Application of pea protein isolate-carboxymethylcellulose complex in emulsions[J].Science and Technology of Food Industry, 2020, 41(21):75-80.
[23] MOLINA ORTIZ S E, PUPPO M C, WAGNER J R.Relationship between structural changes and functional properties of soy protein isolates-carrageenan systems[J].Food Hydrocolloids, 2004, 18(6):1 045-1 053.
[24] KIM H J, DECKER E A, MCCLEMENTS D J.Influence of protein concentration and order of addition on thermal stability of beta-lactoglobulin stabilized n-hexadecane oil-in-water emulsions at neutral pH[J].Langmuir:the ACS Journal of Surfaces and Colloids, 2005, 21(1):134-139.
[25] DUCEL V, RICHARD J, POPINEAU Y, et al.Rheological interfacial properties of plant protein-Arabic gum coacervates at the oil-water interface[J].Biomacromolecules, 2005, 6(2):790-796.
[26] AZARIKIA F, ABBASI S.Efficacy of whey protein-tragacanth on stabilization of oil-in-water emulsions:Comparison of mixed and layer by layer methods[J].Food Hydrocolloids, 2016, 59:26-34.
[27] LEERMAKERS F A M, ATKINSON P J, DICKINSON E, et al.Self-consistent-field modeling of adsorbed β-casein:Effects of pH and ionic strength on surface coverage and density profile[J].Journal of Colloid and Interface Science, 1996, 178(2):681-693.
