Effects of Three Emulsion Compositions on Taste Thresholds and Intensity Ratings of Five Taste Compounds

Abstract

This study assessed the effects of three emulsified systems on taste thresholds and the near-threshold taste intensities of the five tastes (sweet, sour, salty, bitter and umami). Emulsions were formulated with different lipid chemical compositions. Lipid addition in an emulsified form significantly increased thresholds for sour and bitter tastes produced by citric acid and quinine hydrochloride, respectively. No significant differences were found in the threshold levels in emulsions formulated with different lipids for the five tastes evaluated. In general, for the same tastant concentration, taste intensities for sour and bitter tastes were lower in emulsions compared with the aqueous solutions, which is related to the higher threshold observed in the emulsions. On the other hand, the presence of a lipid phase increased the perception of umami and saltiness, with higher intensity values observed in the emulsions. Finally, lipid addition did not affect sweet intensities. These results suggest that, depending on the type of tastant used, the presence of a lipid phase in an emulsified form may alter the sensory perception of foods. Further research needs to be made for specific products to evaluate the effects of specific ingredients on the sensory properties of foods. PRACTICAL APPLICATIONSConsumers are aware of the health consequences associated with their diets. Current tendencies of incorporating a healthy diet in consumers' everyday lives have challenged food manufacturers to produce foods with improved nutritional qualities while maintaining their sensory characteristics. Some of these improvements include the formulation of low-sodium, low-carbohydrate 1 Corresponding

Evaluation of Bitterness Intensity of Citrus Products by an Untrained Panel Using Relative-to-Reference Rating

“…We may hypothesize that these subjects perceive the bitterness difference less clearly in an oily matrix than in aqueous solution. This observation agrees with Thurgood and Martini [43] who found that the bitterness was perceived with a lower intensity in a lipid phase than in an aqueous solution.…”

“…However, any modification in the structure of the matrix (e.g. the droplet size of the emulsion [38,43]) or in the nature of the lipids [37] could also influence taste perception.…”

Quantification of sensory difference thresholds for fat and sweetness in dairy-based emulsions

“…In systems with low or intermediate viscosity, a direct dependency of sensory creaminess on the volume fraction of emulsified oil has been observed by, e.g., Akhtar, Stenzel, Murray, and Dickinson (2005), de Wijk and Prinz (2005), Dresselhuis et al (2008), and Wendin and Hall (2001), whereas droplet size appears to be of minor importance (Akhtar et al, 2005;Vingerhoeds, de Wijk, Zoet, Nixdorf, & van Aken, 2008). Interactions between emulsion composition and chemical sensations are evident from Malone, Appelqvist, and Norton (2003) who reported that emulsion concentration affects flavor release in the mouth, and from Thurgood and Martini (2010) who showed that the recognition thresholds of the five tastes significantly differ when presented in aqueous solution or in O/W emulsions, whereas Akhtar, Murray, and Dickinson (2006) did not observe any effect of incorporated flavor on the sensory perception of emulsion thickness and creaminess. The exact mechanisms which are the basis of sensations such as creaminess, fattiness or thickness are, however, still not fully understood (Terpstra et al, 2009).…”

Physical Approaches to Masking Bitter Taste: Lessons from Food and Pharmaceuticals

“…This may be a physical effect, due to the different polarities of the oils affecting the distribution of the bitter molecules, or a cognitive effect due to the different affinities of different fatty acids for the CD-36 “fatty taste receptor” (135), the aroma of fatty acid oxidation products, or the bitterness of unsaturated free fatty acids (95, 136). Other workers have seen no effect of lipid type on bitter taste in emulsions (137). …”