Research Methodology
11 Formulating Research Questions
Formulating proper research questions in sensory science involves defining the goal and choosing the right methods.
First, define the goal. Decide on the desired outcome of the test: what knowledge needs to be gained? Is the goal to understand consumer preferences, find differences between products, or describe sensory attributes?
Next, define the sensory attributes. Clearly define which attributes are to be studied, such as bitterness, texture, or appearance. Be specific to make sure that all participants interpret the questions exactly the 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?’.
Finally, choose the proper method. Select the best fitting method based on the goal. Here, a clear 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, as participants are not asked to describe the differences. Also, a choice between analytical and hedonic questions (or a possible combination) should be made, as outcomes of each can influence results. For more information, see chapter 2. A Crucial Difference: Analytical Versus Hedonic Evaluation.
See in Example 3 how researchers define their research goal and questions, and how they choose their methods.
Example 3 – Trans Fats
Dietary consumption of trans fats has been shown to increase LDL-cholesterol in the blood and lower HDL-cholesterol, thereby increasing the risk of cardiovascular disease. As a result, public health institutes encouraged companies in the early 2000’s to reformulate their products to cut trans fats.
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 cut trans fats from these products in the Netherlands. To ensure that consumers were still satisfied with the products they used to buy, information needed to be gathered to optimise product reformulations and assess consumer acceptance. For these distinct sensory methodologies were used.
Below some sensory tests and the research questions they could answer are given:
- QDA: What are the sensory profiles of the old and new product in terms of fattiness, spreadability, aroma and appearance? Which attributes are differently perceived?
- Ranking test: How do consumers rank the new formulations compared to each other, which one is mostly preferred?
- Triangle test: Can consumers detect a difference between the old product and the new product?
Analytical testing refers to the objective measurement of the intensity of a sensation
hedonic testing refers to the subjective evaluation of a sensation, for example, liking or palatability.