Linked Life Data

12137497

Source:http://linkedlifedata.com/resource/pubmed/id/12137497

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2002-7-24
pubmed:abstractText
pH-Induced cold gelation of whey proteins is a two-step process. After protein aggregates have been prepared by heat treatment, gelation is established at ambient temperature by gradually lowering the pH. To demonstrate the importance of electrostatic interactions between aggregates during this latter process, beta-lactoglobulin aggregates with a decreased iso-electric point were prepared via succinylation of primary amino groups. The kinetics of pH-induced gelation was affected significantly, with the pH gelation curves shifting to lower pH after succinylation. With increasing modification, the pH of gelation decreased to about 2.5. In contrast, unmodified aggregates gel around pH 5. Increasing the iso-electric point of beta-lactoglobulin via methylation of carboxylic acid groups resulted in gelation at more alkaline pH values. Comparable results were obtained with whey protein isolate. At low pH disulfide cross-links between modified aggregates were not formed after gelation and the gels displayed both syneresis and spontaneous gel fracture, in this way resembling the morphology of previously characterized thiol-blocked whey protein isolate gels (Alting, et al., J. Agric. Food Chem. 2000, 48, 5001-5007). Our results clearly demonstrate the importance of the net electric charge of the aggregates during pH-induced gelation. In addition, the absence of disulfide bond formation between aggregates during low-pH gelation was demonstrated with the modified aggregates.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-8561
pubmed:author
pubmed:issnType
Print
pubmed:day
31
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4682-9
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Physical and chemical interactions in cold gelation of food proteins.
pubmed:affiliation
Wageningen Centre for Food Sciences, Diedenweg 20, 6700 AN Wageningen, The Netherlands. Alting@NIZO.nl
pubmed:publicationType
Journal Article