为了探究不同类型的凝固剂对豆腐中蛋白质消化特性的影响,分别采用酸类凝固剂葡萄糖酸内酯(glucono-δ-lactone,GDL)、盐类凝固剂石膏(CaSO4)以及二者复配的凝固剂制作豆腐。经体外模拟消化后测定其可溶性蛋白质含量、小肽含量(<10 kDa)、水解度(degree hydrolysis,DH)、SDS-PAGE、体外蛋白消化率等变化情况。结果表明,在3种凝固剂制作的豆腐样品中,GDL豆腐和复配凝固剂制作的豆腐其体外蛋白消化率无显著差异(P＞0.05),但均显著高于CaSO4豆腐(P＜0.05)。通过分析其消化期间SDS-PAGE图谱可知,3种豆腐中蛋白质的降解规律相似;但消化末期可溶性蛋白含量、小肽含量及DH的变化均以复配型豆腐最高。因此,复配凝固剂制作豆腐更利于大豆蛋白的消化吸收。
To explore the effect of different coagulants on the digestibility of soy protein in tofu, acid coagulant glucono-δ-lactone (GDL), salt coagulant gypsum (CaSO4) and their mixture were used for the preparation of tofu. The soluble protein content, peptide content (<10 kDa), degree of hydrolysis (DH), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and protein digestibility were determined using in vitro digestion system. The results showed that there was no significant difference in protein digestibility between GDL tofu and mixed-coagulants tofu (P>0.05), but they were significantly higher than CaSO4 tofu (P<0.05). The degradation of protein in the three kinds of tofu was similar according to the SDS-PAGE patterns. However, the mixed-coagulants tofu had the highest soluble protein content, peptide content and DH at the end of digestion. Therefore, the preparation of tofu with mixed coagulant is more conducive to the digestion and absorption of soy protein.
[1] ZHANG Q,WANG C Z,LI B K,et al.Research progress in tofu processing:From raw materials to processing conditions[J].Critical Reviews in Food Science and Nutrition,2018,58(9):1 448-1 467.
[2] LI M,CHEN F S,YANG B,et al.Preparation of organic tofu using organic compatible magnesium chloride incorporated with polysaccharide coagulants[J].Food Chemistry,2015,167:168-174.
[3] SHEN Y R,KUO M I.Effects of different carrageenan types on the rheological and water-holding properties of tofu[J].LWT-Food Science and Technology,2017,78:122-128.
[4] TSENG Y C,XIONG Y L.Effect of inulin on the rheological properties of silken tofu coagulated with glucono-δ-lactone[J].Journal of Food Engineering,2009,90(4):511-516.
[5] CHANG Y H,SHIAU S Y,CHEN F B,et al.Effect of microbial transglutaminase on the rheological and textural characteristics of black soybean packed tofu coagulating with Agar[J].LWT-Food Science and Technology,2011,44(4):1 107-1 112.
[6] 刘宁,高艺笑,孙钰姬,等.豆腐凝固剂的研究进展[J].中国调味品,2021,46(3):189-194.
LIU N,GAO Y X,SUN Y J,et al.Research progress of tofu coagulants[J].China Condiment,2021,46(3):189-194.
[7] AUGUSTIN M A,SANGUANSRI L,RUSLI J K,et al.Digestion of microencapsulated oil powders:In vitro lipolysis and in vivo absorption from a food matrix[J].Food & Function,2014,5(11):2 905-2 912.
[8] HUR S J,LIM B O,DECKER E A,et al.In vitro human digestion models for food applications[J].Food Chemistry,2011,125(1):1-12.
[9] XING G L,RUI X,WANG D,et al.The effect of fermentation pH on the protein bioaccessibility of soymilk curd with added tea polyphenols as assessed by in vitro gastrointestinal digestion[J].Journal of Agricultural and Food Chemistry,2017,65(50):11 125-11 132.
[10] SHIM S M,CHOI M H,PARK S H,et al.Assessing the digestibility of genetically modified soybean:Physiologically based in vitro digestion and fermentation model[J].Food Research International,2010,43(1):40-45.
[11] BRADFORD M M.A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding[J].Analytical Biochemistry,1976,72(1-2):248-254.
[12] RUI X,FU Y T,ZHANG Q Q,et al.A comparison study of bioaccessibility of soy protein gel induced by magnesiumchloride,glucono-δ-lactone and microbial transglutaminase[J].LWT-Food Science and Technology,2016,71:234-242.
[13] NIELSEN P M,PETERSEN D,DAMBMANN C.Improved method for determining food protein degree of hydrolysis[J].Journal of Food Science,2001,66(5):642-646.
[14] KALPANADEVI V,MOHAN V R.Effect of processing on antinutrients and in vitro protein digestibility of the underutilized legume,Vigna unguiculata (L.) Walp subsp.unguiculata[J].LWT-Food Science and Technology,2013,51(2):455-461.
[15] 刘丽莎,金杨,张小飞,等.盐卤豆腐与内酯豆腐质构与分子间作用力比较研究[J].食品科技,2020,45(10):60-64.
LIU L S,JIN Y,ZHANG X F,et al.Comparative study on structure and chemical interaction between brine tofu and GDL tofu[J].Food Science and Technology,2020,45(10):60-64.
[16] RIOUX L E,TURGEON S L.The ratio of casein to whey protein impacts yogurt digestion in vitro[J].Food Digestion,2012,3(1-3):25-35.
[17] RUI X,ZHANG Q Q,HUANG J,et al.Does lactic fermentation influence soy yogurt protein digestibility:A comparative study between soymilk and soy yogurt at different pH[J].Journal of the Science of Food and Agriculture,2019,99(2):861-867.
[18] CARBONARO M,MASELLI P,NUCARA A.Structural aspects of legume proteins and nutraceutical properties[J].Food Research International,2015,76:19-30.
[19] 杨文博,张英华.蛋白质水解度的测定方法研究[J].中国调味品,2014,39(3):88-90.
YANG W B,ZHANG Y H.Study on the determination methods for hydrolysis degree of protein[J].China Condiment,2014,39(3):88-90.
[20] WANG Y T,WANG Z J,HANDA C L,et al.Effects of ultrasound pre-treatment on the structure of β-conglycinin and glycinin and the antioxidant activity of their hydrolysates[J].Food Chemistry,2017,218:165-172.
[21] HSIEH J F,YU C J,TSAI T Y.Proteomic profiling of the coagulation of soymilk proteins induced by magnesium chloride[J].Food Hydrocolloids,2012,29(1):219-225.
