Comparison of protein chemical and physicochemical properties of rapeseed cruciferin with those of soybean glycinin.
Rapeseeds contain cruciferin (11S globulin), napin (2S albumin), and oleosin (oil body protein) as major seed proteins. The effects of oil expression and drying conditions on the extraction of these proteins from rapeseed meal were examined. The conditions strongly affected the extraction of oleosin and only weakly affected the extraction of cruciferin and napin. The protein chemical and physicochemical properties of cruciferin, the major protein present, were compared with those of glycinin (soybean 11S globulin) under various conditions. In general, cruciferin exhibited higher surface hydrophobicity, lower thermal stability, and lower and higher solubility at mu= 0.5 and mu = 0.08, respectively, than did glycinin. At the pHs (6.0, 7.6, and 9.0) and ionic strengths (mu= 0.08 and 0.5) examined, the emulsifying ability of cruciferin was worse than that of glycinin, except at mu= 0.08 and pH 7.6. The emulsifying abilities of cruciferin and glycinin did not correlate with thermal stability and surface hydrophobicity. Higher protein concentration, higher heating temperature, higher pH, and lower ionic strength were observed to produce harder gels from cruciferin. Gel hardness partly correlated with the structural stability of cruciferin.
Mohamed Salleh
Mohamad Ramlan Bin
MR
Laboratory of Food Quality Design and Development, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.
Maruyama
Nobuyuki
N
Adachi
Motoyasu
M
Hontani
Naho
N
Saka
Shiori
S
Kato
Noboru
N
Ohkawa
Yasunobu
Y
Utsumi
Shigeru
S
D055516:2S Albumins, Plant; D000485:Allergens; D052179:Antigens, Plant; D029688:Brassica napus / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004355:Drug Stability; D005079:Excipients; D005782:Gels; D005916:Globulins / Q000032:analysis / Q000737:chemistry*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D010940:Plant Proteins / Q000032:analysis / Q000737:chemistry*; D055314:Seed Storage Proteins; D012639:Seeds / Q000737:chemistry; D012995:Solubility; D030262:Soybean Proteins; D013025:Glycine max / Q000737:chemistry*
D055516:2S Albumins, Plant; D000485:Allergens; D052179:Antigens, Plant; D005079:Excipients; D005782:Gels; D005916:Globulins; D010940:Plant Proteins; D055314:Seed Storage Proteins; D030262:Soybean Proteins; C059777:cruciferin protein, Brassica napus; C079356:oleosin protein, Brassica napus; C050363:napin protein, Brassica napus; C011474:glycinin