Influence of Phenylthiocarbamide Taster Status on Sensory Perceptions of Fruits, Vegetables and Nuts

Abstract

BackgroundThe sensory properties of foods guide food choices and intake, importantly determining nutritional and health status. Variations in sensitivity to the bitter taste of phenylthiocarbamide (PTC) and other thioamide‐containing compounds is well documented. However, there is mixed evidence regarding the association between bitter taste sensitivity, food preferences and metabolic risk factors.MethodsHealthy female (N=174) and male (N=76) participants (age: 18–24 years) with no food allergies or smoking history were recruited to participate in this cross‐sectional study. Participants underwent sensory tests to rate their liking and taste intensities of 18 local foods (name‐blinded) such as fresh and raw fruits and vegetables i.e. pomegranates, strawberries, peach, plums, kiwis, avocado, olives, broccoli, celery, asparagus, spinach, collard greens, cauliflower, green beans and carrots and roasted nuts i.e. almonds, peanuts, pistachios and on 9‐point hedonic and general labelled magnitude scales respectively. In addition, preference tests were conducted for similar foods matched on nutritive value, but differing in cost and availability. Participants sampled PTC strips (3–5 μg/strip) and were categorized as supertasters (extremely bitter) and non‐tasters (tasteless or other taste). Participants also rated importance of several factors influencing consumption of these foods such as taste, cost, convenience, availability, health and nutrition on a 9‐point scale. In addition, participants underwent anthropometric (i.e. BMI, adiposity, waist circumference etc.) and clinical (blood pressure and blood glucose) measurements. Data were analyzed using Kruskal–Wallis test, Chi‐squared tests and multivariate regression.ResultsOver 70% of participants were familiar with all foods except for collard greens which were correctly identified by only 4% of participants. A majority (68%) of participants were categorized as supertasters i.e. perceiving intense bitterness to PTC. Supertasters perceived 20% greater bitterness in collard greens only and consumed them 28% less frequently than non‐tasters (P<0.05). There was no significant difference in liking ratings of any food by taster status. Supertasters also rated cauliflower, broccoli and strawberries as being more important towards health than non‐tasters (P<0.05). Preference test results indicate that greater than 75% of participants preferred avocados (vs. olives), spinach (vs. collard greens), carrots (vs. celery) and pistachios (vs. peanuts). However, there was no significant difference in preferences for paired foods by taster status (assessed as proportion of individuals that preferred one or the other food). In addition, taster status did not predict BMI, adiposity, fasting blood glucose or blood pressure measurements. In conclusion, bitter taste sensitivity influenced frequency of consumption of only unfamiliar foods i.e. collard greens and not the hedonic responses to foods or metabolic risk factors in this cohort. Hence, food choices are likely governed by both sensory as well as non‐sensory factors.Support or Funding InformationBlum Center UC MercedThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.