Guar foaming albumin: a low molecular mass protein with high foaming activity and foam stability isolated from guar meal.
The water extract of guar meal ( Cyamopsis tetragonolobus) was examined for its foamability. Compared with egg white, the extract showed an extraordinary foam stability: no drainage after 3 h of standing in contrast to 65% drainage for egg white at the same protein concentration. The acid-precipitated protein from the extract was responsible for the high foamability and designated guar foaming albumin (GFA). The foaming activity of GFA was 20 times higher than that of egg white. GFA consisted of two subunits with molecular masses of 6 and 11 kDa linked to each other through disulfide bonds. The cleavage of disulfide bonds in GFA affected the foamability only slightly. GFA remarkably decreased the surface tension of water at low protein concentrations. Immunoblotting analysis demonstrated that GFA did not react to the antisera from allergic patients against plant food. These results suggest that GFA serves as an effective food additive in developing protein-stabilized foam.
Shimoyama
Ami
A
Department of Food and Nutrition, Kyoto Women's University, Higashiyama-ku, Kyoto 605-8501, Japan.
Kido
Shoko
S
Kinekawa
Yoh-ichi
Y
Doi
Yukio
Y
D055598:Chemical Phenomena; D011232:Chemical Precipitation; D031293:Cyamopsis / Q000737:chemistry*; D005503:Food Additives; D006863:Hydrogen-Ion Concentration; D010047:Ovalbumin / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry*
D005503:Food Additives; D010936:Plant Extracts; D010940:Plant Proteins; D010047:Ovalbumin