Consumer testing of functional foods
Consumer testing is common practice in food product development. Here, we describe how new food prototypes containing microencapsulated fish oil are tested by consumers at the Riddet Institute.
Tasting booth hatch
Tasting booths separate tasters so they are not distracted or influenced by others.
New food prototypes developed at the Riddet Institute contain microencapsulated fish oil. These products need to be tested by consumers to ensure they are acceptable.
Consumer testing informs product development
Consumer testing is common practice in the food industry. It allows companies to get feedback on a food product’s quality and acceptability to consumers. This feedback helps them decide whether a product needs further development. Ultimately, if a product is not acceptable to consumers, it will not sell.
Consumer testing includes looking at physical attributes of a food, such as texture or consistency, and sensory attributes, such as flavour and aroma.
Testing is a controlled process
A panel of people are selected to do the testing. The tests are done in a laboratory (test room) where panellists sit in separate booths so they are not distracted or influenced by others. The physical environment is controlled - the room is a neutral colour, free from odours and noise, and the lighting can be controlled to minimise colour differences in food samples. These controls help ensure the test results are accurate and not influenced by the environment.
Testing omega-3 enriched ice cream
To test the functionality of the omega-3 enriched ice cream, researchers look at how fast it melts and the texture. For sensory testing, they use other people to taste the ice cream and tell them how acceptable it is. The researchers need to understand the role of each ingredient so they know how to improve the product.
The food samples are prepared in a separate area and passed to panellists through a hatch. The panellists record their responses to various attributes of the food product on a questionnaire.
Screening people for consumer testing
The researchers screen a group of people to see who has the strongest reaction to fishy flavours. They choose people who are most sensitive to fishy flavours to do the sensory testing of the omega-3 products. Once they’ve chosen a group of people, they train them to use similar words, or descriptors, for the flavours before doing the tasting.
The panellists are given an information sheet and consent form before they start. This explains what is involved, how the results will be used and gives them information about the ingredients in the food. Some people are allergic to fish so it’s important to declare that the product contains fish-derived products.
Tasters selected for specific tests
Selecting people for the panel depends on what information the technologists want to find out. To test for overall liking of a product, they use university students or staff. To find out if the food has a fishy taste or smell, they use a panel of people who are particularly sensitive to fish. This means they have to screen people to pick the ideal panellists.
Preparing tasting portions
Tasting portions are prepared in a separate room and passed through a hatch to tasters.
Preparing the questionnaire
Part of preparing the questionnaire for the tasting panel involves deciding on what words to use to describe the attributes of the food. These are called ‘descriptors’. The panellists have to agree on the meaning of these descriptors so their results can be compared.
Two types of test used
Two common types of consumer tests used for food products containing omega-3 are the ‘overall liking or acceptance’ and the ‘overall difference’ tests.
Describing food characteristics for consumer testing
People involved in consumer testing of foods need to agree on what terms to use to describe food characteristics. At Riddet Institute, researchers come up with a list of descriptors first, then the people on the tasting panel work out what terms they will use.
The ‘acceptance’ test uses a panel of untrained tasters. The tasters score the food product on a rating scale according to how much they like or dislike it. This provides feedback on the general consumer acceptability of the product.
The ‘overall difference’ test uses specially selected and trained panellists to test for fishy taste and odour. In this test, the panellists are given two or more food samples – one is a control with no fish oil, the other has fish oil added. The panellists won’t know which sample is which. Through this test, the food technologists can work out how much fish oil can be added to a food. They use the same test to compare the new product with existing commercial varieties.
