Sour taste all in the genes?
differences in sour taste perception, says a new study from the US
that may lead to identification of the still-elusive taste receptor
that detects sourness in foods and beverages.
How consumers sense food is crucial knowledge for a food industry constantly organising the building blocks of new food formulations. "Demonstrating a genetic component to individual differences in sour taste is the first step in pinpointing the genes that determine sensitivity. The products of those genes, in turn, are likely to be involved in sour taste perception," said lead author Paul Wise from the Monell Chemical Senses Center. Taste is a key driver in the €3.2 trillion global food industry and a greater understanding of the physiology of consumers, could lead to strong market advantages. Talking to FoodNavigator.com, lead researcher Paul Wise said that the research has implications for the food industry and food formulators. "This paper, in conjunction with previous work on sweet, bitter, and savoury taste, suggests that people will differ in how they perceive foods, and that these differences will be determined in part by their genes. "Eventually, it might be possible to infer a great deal about an individual's taste preferences based on their genes. "Information about the genes people express could, for example, help nutritionists ensure compliance with special diets by tailoring foods to individual patients. "More generally, the consumer products industry could produce multiple formulations of products based on genetic differences. Eventually, it might even prove possible to enter information about the taste receptor genes you express into a vending machine, and receive a beverage that has the best chance of appealing to you," he said. The study, published in the journal Chemical Senses, compared sour tasting thresholds for 74 pairs of identical (monozygotic, MZ) and 35 pairs of fraternal (dizygotic, DZ) twins. The researchers used citric acid as the 'sour' taste. MZ twins have nearly identical genes while DZ twins share only about 50 per cent of their genes, meaning that similar responses in MZ than DZ pairs would indicate that genes help determine sensitivity to the taste in question. Computer models of the results showed that the relative contributions of genetic influences were higher than those from environmental influences, accounting for 53 percent of the variation. The findings suggest that someone who inherited a high sensitivity to sour taste may find foods containing lemons or vinegar off-putting, whereas the same foods may be better accepted by a person whose genes make them less sensitive. Wise told this website that the work was ongoing. "The heritability of sour sensitivity suggests that a straightforward analysis of genes for candidate sour receptors might prove fruitful," he said. "Research has suggested some promising candidates for sour taste receptors, including the recently-discovered PKD ion channels. Analyses can determine if individual differences in the genes for candidate receptors are associated with individual differences in sensitivity to sourness. One could also conduct family-based linkage studies. "Scientists, both at Monell and other institutions, continue to work on the problem. Ultimately, there may well be multiple receptor proteins involved in sourness perception, and thus multiple genes that govern sensitivity," he concluded. Source: Chemical Senses Published on-line ahead of print, doi: doi:10.1093/chemse/bjm042 "Twin Study of the Heritability of Recognition Thresholds for Sour and Salty Taste" Authors: P.M. Wise, J.L. Hansen, D.R. Reed, and P.A.S. Breslin