Fig 1.
Contents of androstenone and skatole in biological samples of fat tissue of boars used for the quality control task.
Boar taint compounds were determined in melted back fat using gas chromatography mass spectrometry. Different symbols indicate whether or not samples are considered to be truly boar tainted (●) or untainted (○) based on chemical analysis as per the definition of CHEMHIGH [21].
Fig 2.
Odor detection thresholds for androstenone and skatole of the university panel (left) and the abattoir panel (right) under noise (●) and silent conditions (○) including the panel average for the silent (- - -) and noisy condition (──).
The scores in the threshold test can range between -3 and 20 and they represent a series of binary dilutions of the respective odorant; dilution step -3 corresponds to 8 mMol. That is, a higher dilution step indicates a lower detection threshold, i.e. higher sensitivity. Two assessors of the abattoir panel were obviously insensitive towards androstenone and thus excluded from this analysis. Abattoir noise (70 dB) was applied using headphones.
Fig 3.
Odor identification task performance of the university panel (left) and the abattoir panel (right) under noise (●) and silent conditions (○) including the panel average for the silent (- - -) and noisy condition (──).
The odor identification score ranged between 0 and 30 with the latter score representing a superior performance in identification of various concentrations of androstenone and skatole. Abattoir noise (70 dB) was applied using headphones.
Table 1.
Parameter estimates of the logistic mixed model using the agreement* between sensory and chemical analysis as response variable for the abattoir and the university panel.
Fig 4.
Comparison of averaged fat scores for each sample under noisy and silent condition.
For the abattoir panel A the individual fat scores were either 0 (not tainted) or 1 (tainted). That is, the average score over assessors represents a probability that a given sample is tainted. For the University panel U the original scores ranged from 0 (standard pork fat odor) to 5 (strongly deviation from standard pork fat odor). Abattoir noise (70 dB) was applied using headphones.