1. Sensory Analysis
How to ensure a fair test when carrying out sensory analysis
• It should take place in a quiet area, away from where the food was prepared.
• Include a large sample of people to ensure valid results
• Check one variable at a time to produce accurate results
• To avoid food tasters being disturbed and influenced by other people’s opinions, food tasters should work on their own
• Be done under hygienic conditions
• be accompanied by clear instructions so the tasters know how to carry out the test
• Use charts or computer software to record the results
• Have food samples coded with random letters, such as XYX, ZZY, XZZ, to avoid any bias
• Only the person setting up and carrying out the tasting panel should know which code applies to which food sample to ensure a fair test (blind testing).
• Small samples and same sized servings of food should be given.
• Samples should be presented or served at the same temperature, to prevent the flavours being affected
• Samples should be presented or served on the same coloured plates, usually black or white, to prevent the taster’s senses from being distracted or influenced by background colour and appearance of the food samples.
• Be held in lighting booths so appearance is not affected by shadow or poor lighting conditions
There are five senses involved in the choice and enjoyment of food: sight, smell, taste, touch and sound. The enjoyment of food is a result of a mixture of all these senses working together.
How we taste food
To enjoy the flavours of food, the senses of taste and smell have to work together. The flavours of food are detected by thousands of taste buds on the surface of the tongue (you can feel them as little bumps).
Taste buds have tiny sensitive hairs (microvilli) that send messages to the brain about the flavour of food.
Five different groups of flavours are detected by all taste buds on the tongue which the brain identifies as sweet, salt, sour, bitter and umami (this is how you say it:
oo-ma-mee) (savoury)
Most foods are a combination of many different chemicals that make up their unique flavour. Lots of different chemicals are released from food when we cook it. These are detected by our nose and make us feel hungry. When we put food into our mouths and chew it, these chemicals go up into the nose where the special olfactory (smell) receptors pick them up and send messages to our brains about what they smell like.
Different areas of the brain then combine the information from the taste buds and the olfactory receptors to give us the sensation of different flavours. About 80% of what we taste as flavour actually comes from the information provided by the brain by the olfactory receptors in your nose.
Types of Test: Sensory analysis is a way of measuring the sensory qualities of food (appearance, aroma, taste and texture).
Preference tests are used to find out which food products people like the best. There are 2 different preference tests:
Paired preference: people are given 2 similar samples and asked to say which they prefer.
Hedonic rating test: Used to assess a specific characteristic, e.g. flavour, texture, saltiness, crispness. A 5-point or 7-point scale is used to record the results.
Discriminatory tests: Used to see if people can find out the difference between similar food
samples. There are 2 tests:
Triangle test: Used to see whether tasters can tell the difference between foods, e.g. flavours
of yogurt.
A not A test: People given one sample to try then given 2 more (1 is identical to A and the other is not) and the one that is not A is identified
Grading tests:
Ranking test: Used to sort a variety of foods, e.g. different flavours of crisps and are asked to rank them in order for a particular characteristic, e.g. spiciness, sweetness.
Rating: Used to show how much the tasters like/dislike aspects of the product, e.g. crisps aroma, appearance, taste
and/or texture
Profiling Test: Where the different sensory characteristics are tested. The taster gives each characteristic
a score of 1 to 5 and records this on a star diagram.
Key words:
Appetising: food prepared, cooked and served so well that you want to eat it
Bland: Having no flavour (tasteless)
Olfactory (smell) receptors: Special cells in the nose that pick up smells (aromas).
Senses: the ability of the body to react to things through sight, taste, hearing, smell (aroma) and touch
Sensory analysis: the way of measuring the sensory qualities of food
Sensory descriptors: Words used to describe the characteristics of food
Taste buds: Special cells on the tongue to pick up flavour