ICAR AICE-JRF/SRF Sensory Evaluation & Judging of Dairy Products: practice questions

1 · Physiology of the senses · hard

A judge scores the flavour of a deep-yellow butter higher than an identical pale one. This is an example of:

1. The positional error caused by serving order
2. Adaptation
3. The halo error
4. The contrast error

2 · Physiology of the senses · hard

Pungency, cooling and astringency are perceived through:

1. The trigeminal nerve
2. Olfactory receptors only, through retronasal smell
3. Sweet taste receptors
4. The auditory system

3 · Panel selection, screening and training · hard

Panel performance is monitored for three properties of each assessor. Which set is correct?

1. Speed of tasting, height and age of the assessor
2. Liking, purchase intent and price
3. Discrimination, repeatability and agreement
4. Hardness, springiness and cohesiveness of samples

4 · Discrimination tests: triangle, duo-trio, paired comparison · hard

In a triangle test 18 of 36 assessors are correct. What is the estimated proportion of distinguishers?

1. 0.50
2. 0.17
3. 0.25
4. 0.33

5 · Scorecards for milk, butter, ghee, cheese, ice cream and fermented milks · hard

A major weakness of scorecard grading compared with descriptive analysis plus consumer testing is that:

1. Scorecards cannot detect any defects in flavour or texture
2. Scorecards need hundreds of assessors
3. Scorecards use instruments only
4. Weights are conventional, not measured

6 · Flavour defects of milk and their causes · hard

A fruity, pineapple-like flavour in milk stored cold for a week is typically caused by:

1. Lactococcus lactis maltigenes forming 3-methylbutanal from leucine
2. Riboflavin photosensitisation
3. Psychrotrophs forming ethyl esters
4. Copper-catalysed oxidation

7 · Flavour defects of milk and their causes · hard

A medicinal, phenolic taint in milk at very low concentration is often traced to:

1. Chlorophenols
2. Lipoprotein lipase activity in the raw milk
3. High lactose content
4. Riboflavin destruction

8 · Statistics of sensory data · hard

External preference mapping:

1. Performs principal component analysis on the liking scores only
2. Counts correct triangle answers
3. Regresses liking on sensory dimensions
4. Ranks cheeses by price

9 · Statistics of sensory data · hard

In a directional paired test, 20 of 30 assessors choose the predicted sample. Using the normal approximation without continuity correction, z is about:

1. 0.67
2. 5.00
3. 1.00
4. 1.83

10 · Consumer testing and shelf-life sensory end points · hard

A pasteurised milk is still acceptable to a sensory panel when its count exceeds the plant's specification. What decides its date marking?

1. Sensory acceptability alone, whatever the count
2. Safety limits first; sensory only within them
3. Consumer liking alone
4. The cost of packaging