Research Methodology
11 Formulating research questions
Formulating research questions in sensory science involves defining the objective and choosing the appropriate methods.
First, define the objective. Determine what the desired outcome of the test is: what knowledge is needed to be gained from this test? Is the goal to understand consumer preferences, identify differences between products, or describe sensory attributes?
Then, define the sensory attributes. Clearly define the attributes desired to study, such as bitterness, texture or appearance. Be specific to make sure that all participants interpret questions the exact same. For example, rephrase ‘How do you find the texture of this product?’, to ‘How is the texture of this product in the mouth after the first chew?’.
Last, choose the right method. Select the appropriate test based on the objective. The distinction between direct and indirect tests should be made. Direct tests give detailed and specific information, but indirect tests are less influenced by individual bias since participants are not asked to describe the differences. The distinction between analytical and hedonic tests (or a possible combination) should be made as well, as outcomes of both types of test can influence results. For more information, see the example in chapter 2.
Example – Trans fats
Trans fats are unsaturated fatty acids, and has been shown to increase LDL-cholesterol in the blood, and lower HDL-cholesterol. Through this way, trans fats increase the risk on cardiovascular disease. As a result, public health institutes increased their efforts to encourage companies to reduce trans fat content in their products.. In the past, trans fats were found in hard margarines, frying fats, and cooking fats due to the production process. However, adjustments in the production process have now almost entirely eliminated trans fats from these products in the Netherlands. To ensure that consumers were still satisfied by the products they used to buy, sensory tests were used to optimize product reformulation and test consumer acceptance. Examples of research questions by a company producing margarines are given per sensory test:
- QDA: What are the sensory profiles of the previous and new product in terms of fattiness, spreadability, aroma and appearance?
- Ranking test: How do consumers rank possible new formulations of the margarine based on overall preference?
- Triangle test: Can consumers detect a difference between the previous product and the new product?