Combinational Effect of Moist Heating and Gamma Irradiation on The Inactivation of Trypsin Inhibitory Activity in Soybean

  • Felipe, Penelope (Department of Food and Nutrition, Chungnam National University) ;
  • Yang, Yun-Hyoung (Department of Food and Nutrition, Chungnam National University) ;
  • Lee, Jeong-Hee (Department of Food and Nutrition, Chungnam National University) ;
  • Sok, Dai-Eun (College of Pharmacy, Chungnam National University) ;
  • Kim, Hyoung-Chin (Bio-Evaluation Center, Korea Research Institute of Bioscience and Biotechnology) ;
  • Yoon, Won-Kee (Bio-Evaluation Center, Korea Research Institute of Bioscience and Biotechnology) ;
  • Kim, Hwan-Mook (Bio-Evaluation Center, Korea Research Institute of Bioscience and Biotechnology) ;
  • Kim, Mee-Ree (Department of Food and Nutrition, Chungnam National University)
  • Published : 2005.12.31


The combinational effect of gamma irradiation and moist heating on the trypsin inhibitor activity (TIA) in soaked and dried soybeans was evaluated by measuring the inhibition using N-benzoyl-DL-arginine-p-nitroanilide (BAPNA) as substrate. Gamma irradiation significantly decreased the TIA level in soybean at doses above 5 kGy, and the $ID_{50}$ (the gamma irradiation dose required to reach 50% inhibition) value for TIA was 13.53 kGy. Soaking prior to gamma irradiation significantly lowered the $ID_{50}$ to 8.44 kGy, and the soaking process enhanced the efficiency to inactivate TIA by as much as 48%. When soaking prior to gamma irradiation was followed by subsequent mild heating ($60^{\circ}C$) process, the $IT_{50}$ (heating time required to reach the 50% inhibition of TIA) value at even 1 kGy (5.28 min) was greatly reduced by over 50% compared to the level for the no-soaking process. In addition, the activation energy of soaking prior to gamma irradiation at 1 kGy was 2.45 kcal/mole, which was also about 50% lower than the 5.10 kcal/mole of dried soybean gamma-irradiated. Based on these results, soaking prior to gamma irradiation is an effective method for TIA inhibition. Furthermore, a combination of two or more processing methods such as soaking, heating and gamma irradiation is much more effective than any single processing method.


  1. J. Am. Oil Chem. Soc. v.56 Significance for hwnan and biologically active factors in soybeans and other food legumes Liener, I.E.
  2. Korean Soybean Dig. v.15;2 Current research on the bioactive functions of soybeans in Korea Kwon, T.W.;Song, Y.S.;Kim, J.S.;Moon, G.S.;Kim, J.I.;Hong, J.H.
  3. Antinutritional factors related to proteins and amino acids;Foodbome Disease Handbook. Vol. III Liener, I.E.;Hui, Y.H.(ed.);Gorham, J.R.(ed.);Murrel, K.D.(ed.);Cliver, D.O.(ed.)
  4. Crit. Rev. Food Sci. Nutr. v.21 Technology of removal of unwanted components of dry beans Sathe, S.K.;Salunkhe, O.K.
  5. J. Sci Food Agric. v.81 Effect of various indigenous processing methods on alpha-galactoside, mono- and disaccharide content of an Indian tribal pulse, Mucuna pruriens var. utilis Siddhuraju, P.;Becker, K.
  6. J. Agric. Food Chem. v.49 Effect of various domestic processing methods on antinutrients and in vitro protein and starch digestibility of two indigenous varieties of Indian tribal pulse, Mucuna pruriens var. utilis Siddhuraju, P.;Becker, K.
  7. Effects of processing on antinutritional factors (ANF) and nutritional value of legume seeds for nonruminant feeding;Recent advances of research in antinutritional factors in legume seeds Van der Poel, A.F.B.; Huisman, J.(ed.);van der Poel, A.F.B.(ed.);Liener, I.E.(ed.
  8. Irradiation of dry food ingredients Farkas, J.
  9. Food irradiation: principles and applications Molins, R.A.
  10. Food irradiation Thome, S.
  11. Korean Soybean Dig. v.16 no.2 Effects of gamma irradiation for improvement of physical, chemical and processing properties of soybeans Byun, M.W.;Yook, H.S.;Lee, K.H.;Kim, J.K.;Cha, B.S.;Kim, W.J.
  12. Food Chem. v.78 The effect of ionising radiation on antinutritional factors and the nutritional value of plant materials with reference to human and animal food Siddhuraju, P.;Makkar, H.P.S.;Becker, K.
  13. Egy. J. Rad. Sci. Appl. v.6 Radiation deactivation of antinutritional factors: trypsin inhibitor and hemagglutinin in soybeans Farag, M.D.E.H.
  14. Moisture-air-oven methods;AOAC Official Methods of Analysis AOAC
  15. Determination of trypsin inhibitor activity of soy products: A collaborative analysis of improved procedure Kakade, M.L.;Rackis, J.J.;McGhee, J.E.;Puski, G.
  16. J. Nutr. v.126 no.3 The composition of glyphosate-tolerant soybean seeds is equal to that of conventional soybeans Padgette, S.R.;Taylor, N.B.;Nida, D.L.;Bailey, M.R.
  17. J. Nutr. v.125 no.3 Compositional changes in trypsin inhibitors, phytic acid, saponins and isoflavones related to soybean processing Anderson, L.R.;Wolf, W.J.
  18. Analysis of variance I: The one-way classification;Principles and Procedures of Statistics Steel, R.G.D.;Torrie, J.H.
  19. Wholesomeness of irradiated foods;Report on Joint FAO/IAEAlWHO Expert Committee WHO
  20. J. Agric. Food Chem. v.46 Irradiation inactivation of some antinutritional factors in plant seeds Abu-Tarboush, H.M.
  21. Minia J. Agric. Res. Dev. v.12 Effect of y-irradiation on some antinutritional factors in kidney bean (Phaseolus vulgaris L.) seeds Ghazy, M.A.
  22. Nutr. Rep. Int. v.23 Inactivation studies on the trypsin inhibitor activity of green gram cultivars Haider, F.
  23. Qual. Plant Foods Human Nutr. v.30 Quick-cooking beans (Phaseolus vulgaris L.): II. phytates, oligosaccharides and antienzymes Iyer, V.;Salunkhe, O.K.;Sathe, S.K.;Rockland, L.B.
  24. J. Food Sci. v.50 Effect of y-irradiation on protein and fatty acids of soybean Hafez, Y.S.;Mohamed, A.I.;Singh, G.;Hewedy, F.M.
  25. J. Sci. Food Agric. v.79 Effect of radiation and other processing methods on protein quality of sunflower meal Farag, M.D.E.H.
  26. Food Chem. v.34 Effect of soaking and germination temperatures on selected nutrients and antinutrients of mung bean Sattar, A.;Durrani, S.K.;Mahmood, F.;Ahmad, A.;Khan, I.
  27. Nahrung v.34 Effect of radiation and soaking on trypsin inhibitor and protein content of chickpea (Cicer arietinum L.) Sattar, A.;Atta, S.;Akhtar, M.A.
  28. Food Sci. Biotechnol. v.11 no.6 Effects of microwave radiation on content of soybean soluble proteins, trypsin inhibitor and urease activity Zilic, S.M.;Bozovic, I.N.;Mladenovic-Drinic, S.O.;Savic, S.;Bekric, V.L.