Occurrence of major whey proteins in the pH 4.6 insoluble protein fraction from UHT-treated milk.
J Agric Food Chem
; 60(32): 8044-50, 2012 Aug 15.
Article
in En
| MEDLINE
| ID: mdl-22809470
ABSTRACT
A clear picture of the protein rearrangement in milk following UHT-treatment was drawn by a comparative analysis of the pH 4.6 soluble protein fraction (SPF) and the pH 4.6 insoluble protein fraction (IPF) recovered from raw and UHT-treated milk samples. The two protein fractions were analyzed by mono- or bidimensional gel electrophoresis under reducing and nonreducing conditions, and protein bands were identified by specific immunostaining. Results showed that bovine serum albumin, ß-lactoglobulin, and, to a lesser extent, α-lactalbumin coprecipitated with caseins in UHT-treated milk samples at pH 4.6. These proteins were almost exclusively involved in high molecular weight aggregates held together by disulfide bonds. Partition of α-lactalbumin and bovine serum albumin in the protein fractions obtained upon acidification of milk at pH 4.6 was evaluated by competitive immunoassays. The ELISA-based results suggested the possibility of using pH 4.6 insoluble α-lactalbumin and bovine serum albumin, in addition to pH 4.6 insoluble ß-lactoglobulin, as indicators of the intensity of the heat treatment applied to milk.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Milk
/
Food Handling
/
Hot Temperature
/
Milk Proteins
Limits:
Animals
Language:
En
Journal:
J Agric Food Chem
Year:
2012
Document type:
Article
Affiliation country:
Italy
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA