The Effects of Excluding Animal Products from the Diet on Sensory Properties of Pork from Pigs Grown in New Zealand as Assessed by Singaporean Panelists

  • Leong, Jasmine (Massey University, Institute of Food, Nutrition and Human Health) ;
  • Purchas, Roger W. (Massey University, Institute of Food, Nutrition and Human Health) ;
  • Morel, Patrick C.H. (Massey University, Institute of Food, Nutrition and Human Health) ;
  • Wilkinson, Brian H.P. (Massey University, Institute of Food, Nutrition and Human Health)
  • Received : 2009.06.17
  • Accepted : 2009.09.12
  • Published : 2010.01.01


Sensory analyses of pork samples from leg muscles of female pigs raised in New Zealand (n = 17) were conducted using trained and untrained Singaporean panelists. The New Zealand pigs included three dietary groups, with one diet including animal products (NZA), and two containing plant products only (NZP & NZP+), with the NZP+ diet containing a supplement (0.614%) containing conjugated linoleic acid (CLA), selenium, and vitamin E. The New Zealand pork was also compared with Indonesian pork as local reference samples (n = 6). Pork samples from the NZA group had the highest score for mutton flavour and aftertaste, and the lowest score for brothy aroma, brothy flavour, meaty flavour, lightness and juiciness by trained sensory panels. Samples from NZP and NZP+ were similar except the NZP+ group had a stronger stale flavour than the NZP group (1.34 vs. 0.57 on a 100-point scale; p<0.05). The first and second functions of a discriminant analysis based on trained-panel scores for 14 attributes accounted for 95.4% of the variance, with function 1 (83.7%) being related mainly to mutton aroma, mutton flavour and aftertaste. Based on a 20-member untrained panel, the NZA pork had the highest mutton aroma and mutton flavour intensities (p<0.01) and aroma and flavour that was less acceptable than that from the NZP group (p<0.05). The acceptability scores of Indonesian pork were not significantly different from those of New Zealand pork, but its scores for mutton aroma and mutton flavour were significantly lower than NZP. Overall acceptability was positively associated with acceptability of aroma (r = 0.906), juiciness (r = 0.888), and tenderness (r = 0.904), but negatively associated with intensities of mutton aroma (r = -0.478) and flavour (r = -0.551).


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