Descriptive sensory analysis of toothpaste flavor and texture using two sampling methods: brushing versus spoon tasting

Repeated testing of toothpaste using a brushing method can lead to dental sensitivity, which could compromise the effectiveness of descriptive evaluations. The objective of this research was to compare flavor and texture evaluations of toothpaste using two sampling methods, toothbrushing or spoon tasting, in a descriptive sensory analysis test. A highly trained descriptive sensory panel evaluated five commercially available toothpastes using the two sample delivery regimens. Changing the sample delivery method impacted key toothpaste attributes, including burn, nasal cooling, toothetch and associated flavor attributes such as overall mint, menthol and bitter, but no interaction of product and method was found for those attributes. The interaction between product and delivery technique, i.e., specific toothpastes react differently than others when the sampling technique is changed, occurred in graininess, foaminess, baking soda, oral cooling and tongue numbing. This research establishes that the delivery method for toothpaste during descriptive analysis has an impact on flavor evaluations. Although it is possible to use an alternate method, such as spoon tasting, for some toothpaste evaluations if the attributes of interest do not show interactions between product and method, researchers must give consideration to how alternate methods affect intensity of scores or other outcomes of the research. Researchers seeking to use atypical sampling methods for various reasons (i.e., sample screening, limited resources, reducing evaluator's fatigue), especially for products such as toothpaste, must consider the objectives of a study and how an alternate technique will affect the outcome of the research. This research establishes that the delivery method of toothpaste during descriptive analysis has an impact on the flavor and texture evaluations. It is possible to use an alternate, such as sampling from a spoon for toothpaste evaluations, with the understanding that key attributes such as cooling and mint flavor will be amplified. The spoon method can be useful in screening when there is a need to efficiently gather information on a myriad of similar products, but it probably needs to be avoided in situations where products differ widely or key attributes are compromised.