The rigor bond’s interaction with protein denaturation : effects on water-holding of myofibrils

The aim of the experimental work was to understand the rigor bonds’ effect together with protein denaturation on water-holding capacity by breaking the actomyosin bonds that were formed during rigor process and examining the dissociation of actomyosin bonds’ influence on rheological features of myofibrils in suspension. In this study the rigor bonds’ influences on water-holding capacity were compared; firstly, by dissociating the rigor bonds in one group with the addition of 10mM PPi and 2mM MgCl2; secondly, applying heat treatment at 21ºC and 44 ºC; thirdly, denaturing sarcoplasmic proteins together with the myofibrils and denaturing the myofibrils without the presence of sarcoplasmic proteins. The influence of actomyosin bonds’ dissociation on rheological features of myofibrils was investigated as well by stress sweep and frequency sweep tests. The samples that were denatured without the presence of sarcoplasmic protein showed the poorest water-holding capacity which is indicating high drip loss in PSE like conditions mainly due to myofibrillar protein denaturation. Sarcoplasmic protein precipitation with the myofibrils improved the gelling properties. The PPi addition did not affect water-holding of myofibrils (P>0.05), suggesting that the rigor bonds don’t have a significant effect on water-holding of myofibrils after temperature-induced protein denaturation.

Grantor dc:publisher

Helsingfors universitet

Year dc:date.issued

2016

Author dc:creator

• Özge Nilay, Yurdakul

Contributors dc:contributor

• Helsingin yliopisto, Maatalous-metsätieteellinen tiedekunta, Elintarvike- ja ympäristötieteiden laitos
• University of Helsinki, Faculty of Agriculture and Forestry, Department of Food and Environmental Sciences
• Helsingfors universitet, Agrikultur- och forstvetenskapliga fakulteten, Institutionen för livsmedels- och miljövetenskaper

• PSE
• water-holding capacity
• protein denaturation
• pyrophosphate
• actomyosin bonds

Language dc:language.iso

eng

Identifier URI

URN:NBN:fi:hulib-201612143289

OAI identifier oai:identifier

oai:helda.helsinki.fi:10138/172491