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various types of egg white gels could be obtained by dialyzing
chicken egg white, with subsequent pH and protein concentration
adjustment, followed by heating at 80℃ water for 1 hr. The
purpose of this exeriment was to investigate the possibility of
industry-scale dialysis of chicken egg white with hollow fiber
diafiltration to remove the low molecular weight materials in
large amount. The development of fruit jelly-like egg white
jelly protuct with the dialyzed chicken egg white was also
studied. There were five treatments for the egg white:(1)
control egg white (2)diluted egg white (3)laboratory dialysis
of egg white (molecular weight 12000 cutoff) (4)hollow fiber
diafiltration of egg white(molecular weight 3000 cutoff) (5)
hollow fiber diafiltration of egg white(molecular weight 10000
cutoff). All of the treated egg white were subjected to
determination of proximate composition, polyacrylamide gel
electrophorsis (PAGE), transparency and beaking strength of the
heated gel. Results showed that except for the decrease of ash
content for the dialyzed egg white, there was no difference in
protein concentration and total solids for all treated egg
white. Similar PAGE protein bands were observed on the
laboratory or hollow fiber dialyzed egg white. The transparency
of heated dialyzed-egg white, either from laboratory or hollow
fiber, was increased at acidic pH values in comparison with
control egg white. It was concluded that there was no
difference on the dialysis of egg white from both laboratory
and hollow fiber. However, the hollow fiber diafiltration could
increase the productivity of egg white dialysis. Chicken egg
white was subjected to Aspergillus oryzae protease hydrolysis
at 37℃ for 1 hr before hollow fiber diafiltration. The
dialyzed egg white showed lower concentration of larger
molecular weight material, and lower breaking strength of the
heated egg white gel as compared to the dialyzed, no- enzyme
hydrolyzed egg white.
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