Negative effect of combining microbial transglutaminase with low methoxyl pectins on the mechanical properties and colour attributes of fish gels

The objective of this work was to determine the effect of combining different concentrations of microbial transglutaminase (MTGase) and types of low methoxyl (LM) pectin on the mechanical properties (textural profile analysis, puncture test) and the colour attributes of fish restructured products. A disruptive effect was observed when LM pectin and MTGase were added to fish gels. Adding 1% MTGase with LM32 pectin significantly decreased the hardness (3.85 kg), springiness (0.631) and chewiness (0.434 kg). When LM32 pectin and 0.1% MTGase were added together, significant decreases of the three puncture test parameters were observed. The chroma of fish gels decreased significantly when 0.3% MTGase was added. Fish gels containing the LM35 pectin had higher chroma values than all other fish gels with the same level of MTGase. Hue value was increased in all fish gels after increasing the MTGase level. The results obtained showed that LM pectin is not suitable for use in products containing MTGase.