Thermal stability of connective tissue and meat quality of loose structured porcine semimembranosus muscles

Författare

• Liisa Voutila Department of Food Technology, University of Helsinki, P.O. Box 66, Viikki EE, Helsinki 00014, Finland
• Anne Maria Mullen Teagasc, The National Food Centre, Dunsinea, Castleknock, Dublin 15, Ireland
• Paul Allen Teagasc, The National Food Centre, Dunsinea, Castleknock, Dublin 15, Ireland
• Declan Troy Teagasc, The National Food Centre, Dunsinea, Castleknock, Dublin 15, Ireland
• Eero Puolanne Department of Food Technology, University of Helsinki, P.O. Box 66, Viikki EE, Helsinki 00014, Finland

DOI: https://doi.org/10.33354/smst.76779

Nyckelord:

Connective tissue, porcine semimembranosus, meat quality, differential scanning calorimetry

Abstract

Loose structure and PSE like zones on the lateral surface of porcine semimembranosus muscle have been
observed by other researchers. However the role of connective tissue in this abnormally loose structure in
semimembranosus muscle has not yet been clarified. We collected about 100g samples from 7 loose
structured and 7 normal structured Irish commercial porcine semimembranosus muscles in order to
compare the onset and peak of thermal transition temperature of intramuscular connective tissue between
the samples from the two groups. Meat quality parameters, ultimate pH, rough estimate for drip loss,
lightness (L), redness (a) yellowness (b) and as well as electrical conductivity and reflectance were also
measured on the samples. Four of the samples characterized as normal by visual assessment showed DFD
characteristic so the statistical analysis was carried out both including and excluding those samples. In
both cases the onset (p<0.001; 56.94ºC vs. 59.82ºC) and peak (p<0.001; 62.59ºC vs. 64.06ºC) of thermal
transition temperature were significantly lower in loose structured meat than in normal structured meat.
Also reflectance% was lower (p<0.01; 45.18% vs. 69.17%) and the colour lighter (higher L value; p<0.01;
55.05 vs. 45.52) and more yellow (higher b value; p<0.001; 18.27 vs. 14.78) in loose structured meat than
in normal structured meat when the DFD like samples were excluded. These results indicate that loose
structure in porcine semimembranosus muscle could be attributed in part to connective tissue properties
possibly in conjunction with PSE effects.