Visual judgements of quality in meat III. Assessments of bacon qualities by naïve and experienced judges using photographic reference standards

Abstract

1. Two panels of eight students, with no previous experience in scoring bacon sides for eye-muscle qualities or for fatness, co-operated in an experiment involving thirty-five photographs of back rashers of bacon presented to them in batches of twenty at a time. The members of the first panel made their assessments without any guide, whereas those of the second were provided with sets of photographic reference standards showing a graded sequence of rashers scoring from 0 to 10 for each of the two characteristics involved.2. Those provided with the reference standards spread out their scores over the available range more than those who judged without them.3. Judging discrimination between markedly different groups of rashers was improved when the reference standards were available. This was not true of discrimination between similar rashers since repeatability of scoring was to some extent decreased when the standards were used.4. When the reference standards were not available, these inexperienced judges tended to adjust their level of scoring according to the quality of the batch of rashers being assessed. This adaptive effect was eliminated when reference standards were available although apparently random fluctuations of level of scoring from batch to batch still occurred.5. Differences between judges due to their different uses of the available range of scores were less marked, although not entirely eliminated, when reference standards were used by the naive judges. Systematic differences between the scores awarded by various judges remained, as did a few differences of opinion on the relative quality of certain examples.