The influence of soy protein isolate (SPI) substitution for sodium caseinate (SC) on the properties of cold-set (4 °C) and heat-induced gels of pork myofibrillar protein (MP) incubated with microbial transglutaminase (TG) was investigated. The strength of cold-set MP-SC gels (formed in 0.45 M, NaCl, 50 mM phosphate buffer, pH 6.25) increased with time of TG incubation, but those gels with more than 66% SPI substituted for SC had a >26% reduced strength (P < 0.05). Upon cooking, both incubated and non-incubated protein sols were quickly transformed into highly elastic gels, showing up to 6000 Pa in storage modulus (G′) at the final temperature (72 °C). However, no differences (P < 0.05) in G′ were observed between heated samples with SPI and SC. Myosin heavy chain, casein and soy proteins gradually disappeared with TG incubation, contributing to MP gel network formation. Both cold-set and heat-induced gels had a compact protein matrix, attributable to protein cross-linking by TG.
|Number of pages||8|
|Journal||Food Research International|
|State||Published - Oct 2009|
Bibliographical noteFunding Information:
The authors thank Ajinomoto Food Ingredients LLC (Chicago, IL, USA) for providing microbial transglutaminase, FMC biopolymer (Pennsylvania, PE, USA) for donating konjac flour, and American Casein Company (Burlington, NJ, USA) for supplying sodium caseinate for this study. This research was supported, in part, by Biotechnology Research Institute, Chonnam National University.
- Cold-set gels
- Myofibrillar protein
- Sodium caseinate
- Soy protein isolate
ASJC Scopus subject areas
- Food Science