Influence of Sodium Chloride and Glucose on Acid-Induced Gelation of Heat-Denatured Ovalbumin

• Published in: Journal of food science Vol. 73; no. 5; pp. C313 - C322
• Main Authors: Choi, S.J, Lee, S.E, Moon, T.W
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01.06.2008; Institute of Food Technologists; Wiley Subscription Services, Inc
• Subjects: acid treatment; Biochemistry; Biological and medical sciences; cold-set gel; denaturation; Dose-Response Relationship, Drug; Food industries; Food science; Food Technology; Fundamental and applied biological sciences. Psychology; gel strength; gelatinization; gels; Gels - analysis; Gels - chemistry; gluconolactone; Glucose; Glucose - chemistry; Glucose - pharmacology; heat treatment; Hot Temperature; Hydrogen-Ion Concentration; Molecular Weight; Nephelometry and Turbidimetry; ovalbumin; Ovalbumin - analysis; Ovalbumin - chemistry; Ovalbumin - drug effects; Protein Denaturation - drug effects; Proteins; rheological properties; rheological property; Salt; sodium chloride; Sodium Chloride - chemistry; Sodium Chloride - pharmacology; storage modulus; surface interactions; turbidity; Ovalbumin; Heat; Cold; Gelation; cold-set gel; Carbohydrate; Glucose; rheological property; Sodium chloride; Rheological properties
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1750-3841.2008.00770.x

We examined the effects of NaCl and glucose on cold-set ovalbumin gelation. Cold-set gels were prepared by adding glucono-δ-lactone (GDL) to a 2% heated ovalbumin solution. For the gel prepared from ovalbumin heat-denatured with NaCl and glucose, the gel with 10 mM NaCl was most transparent and had high gel strength. Its maximum complex shear modulus (G*) and turbidity were 2.5 times greater and 3 times lower, respectively, than those of the gel without NaCl. The turbidity of the gel with the higher NaCl content increased steeply after the addition of GDL and did not change during the experimental period. The maximum G* of the gel exhibited positive correlations with the molar mass, radius, and surface hydrophobicity of soluble aggregates and the NaCl content, but the turbidity exhibited negative correlations with these factors. The presence of glucose did not significantly affect the turbidity or rheological properties of the gel. For the gel prepared by adding NaCl and glucose with GDL, the presence of glucose did not affect the turbidity, but the maximum G* decreased in inverse proportion to the glucose content. The turbidity of the gel with higher NaCl content (>= 50 mM) was the greatest among all samples, and the increased turbidity was maintained throughout the measurements. The gels with 50 and 100 mM NaCl exhibited thixotropy during shearing at a constant shear rate. Therefore, the presence of NaCl and glucose during cold gelation could facilitate the preparation of cold-set gels having various properties for food applications.