Mari Sandell

Variability in a taste-receptor gene determines whether we taste toxins in food

Document S1. Supplemental Experimental ProceduresxDownload (.49 MB ) Document S1. Supplemental Experimental Procedures

Vegetable bitterness is related to calcium content

In the U.S. and Europe, most people do not consume the recommended amounts of either calcium or vegetables. We investigated whether there might be a connection; specifically, whether the taste of calcium in vegetables contributes to their bitterness and thus acceptability. We found a strong correlation between the calcium content of 24 vegetables, based on USDA Nutrient Database values, and bitterness, based on the average ratings of 35 people (r = 0.93). Correlations between the content of other nutrients and bitterness were lower and most were not statistically significant. To assess whether it is feasible that humans can detect calcium in vegetables we tested two animal models known to display a calcium appetite. Previous work indicates that calcium solutions are preferentially ingested by PWK/PhJ mice relative to C57BL/6J mice, and by rats deprived of dietary calcium relative to replete controls. In choice tests between collard greens, a high-calcium vegetable, and cabbage, a low-calcium vegetable, the calcium-favoring animals had higher preferences for collard greens than did controls. These observations raise the possibility that the taste of calcium contributes to the bitterness and thus acceptability of vegetables.

Pathophysiology of primary burning mouth syndrome with special focus on taste dysfunction: a review.

Primary burning mouth syndrome (BMS) is a chronic oral condition characterized by burning pain often accompanied with taste dysfunction and xerostomia. The most compelling evidence concerning BMS pathophysiology comes from studies on the somatosensory system using neurophysiologic or psychophysical methods such as blink reflex, thermal quantitative sensory testing, as well as functional brain imaging. They have provided convincing evidence for neuropathic involvement at several levels of the somatosensory system in BMS pain pathophysiology. The number of taste function studies trying to substantiate the subjective taste disturbances or studies on salivary factors in BMS is much more limited, and most of them suffer from definitional and methodological problems. This review aims to critically evaluate the existing literature on the pathophysiology of BMS, paying special attention to the correctness of case selection and the methodology used in published studies, and to summarize the current state of knowledge. Based on the recognition of several gaps in the current understanding of the pathophysiology of BMS especially as regards taste and pain system interactions, the review ends with future scenarios for research in this area.

Explaining and predicting individually experienced liking of berry fractions by the hTAS2R38 taste receptor genotype

The roles of taste and astringent properties, food choice motives and health concerns in liking of bilberry and crowberry samples were studied using a sensory panel prescreened for the hTAS2R38 taste receptor genotype. The subjects rated the intensity of sourness, bitterness and two astringent properties (soft, velvety and rough, puckering) of all berry samples. They also scored the liking of juice fractions and completed a food choice motive and health concern questionnaire. Regression models were used to combine different data sets and to predict liking of the extracts. Sourness contributed positively to the liking of berry fractions, and bitterness and rough astringency were negative factors. The hTAS2R38 genotype affected the liking of polyphenol-rich extracts, which were significantly bitter and astringent. Based on the genotype grouping of subjects, PAV homozygotes gave lower ratings to the attributes than AVI homozygotes. In contrast, PAV homozygotes were predicted to dislike the extracts notably more than AVI homozygotes. Health concern and food choice motives related to health and weight control had significant roles in individual liking of juice fractions. Our results indicate that mood was more important to the PAV homozygotes than to the AVI homozygotes.

Nontargeted metabolite profiles and sensory properties of strawberry cultivars grown both organically and conventionally.

Strawberry (Fragaria × ananassa Duch.) contains many secondary metabolites potentially beneficial for human health, and several of these compounds contribute to strawberry sensory properties, as well. In this study, three strawberry cultivars grown both conventionally and organically were subjected to nontargeted metabolite profiling analysis with LC-qTOF-ESI-MS and to descriptive sensory evaluation by a trained panel. Combined metabolome and sensory data (PLS model) revealed that 79% variation in the metabolome explained 88% variation in the sensory profiles. Flavonoids and condensed and hydrolyzable tannins determined the orosensory properties, and fatty acids contributed to the odor attributes of strawberry. Overall, the results indicated that the chemical composition and sensory quality of strawberries grown in different cultivation systems vary mostly according to cultivar. Organic farming practices may enhance the accumulation of some plant metabolites in specific strawberry genotypes. Careful cultivar selection is a key factor for the improvement of nutritional quality and marketing value of organic strawberries.

Aroma formation by immobilized yeast cells in fermentation processes

Immobilized cell technology has shown a significant promotional effect on the fermentation of alcoholic beverages such as beer, wine and cider. However, genetic, morphological and physiological alterations occurring in immobilized yeast cells impact on aroma formation during fermentation processes. The focus of this review is exploitation of existing knowledge on the biochemistry and the biological role of flavour production in yeast for the biotechnological production of aroma compounds of industrial importance, by means of immobilized yeast. Various types of carrier materials and immobilization methods proposed for application in beer, wine, fruit wine, cider and mead production are presented. Engineering aspects with special emphasis on immobilized cell bioreactor design, operation and scale‐up potential are also discussed. Ultimately, examples of products with improved quality properties within the alcoholic beverages are addressed, together with identification and description of the future perspectives and scope for cell immobilization in fermentation processes. Copyright

Children’s hedonic response to berry products: Effect of chemical composition of berries and hTAS2R38 genotype on liking

The hedonic response of 104 healthy children, recruited from day-care centres and schools, to 12 different berry products with varying content of added sugar was studied. The berries used as ingredients were blackcurrant (Ribes nigrum), sea buckthorn (Hippophaë rhamnoides), bilberry (Vaccinium myrtillus), and lingonberry (Vaccinium vitis-idaea). Another aim of the study was to study the effects of the chemical composition of berries as well as childrens hTAS2R38 taste receptor genotypes on liking. The most liked product was bilberry with yoghurt, followed by bilberry juice, dried bilberries, and lingonberry rye bread. The most disliked products were sea buckthorn juice, sea buckthorn berries with yoghurt, and oatmeal with blackcurrant powder and berry oil. High total organic acid concentration was strongly related with a poor average liking score of the berries/berry products. A total of four different alleles of hTAS2R38 gene were observed in the study. Of the genotyped children, 45% were bitter taste insensitive individuals of the genotype AVI/AVI, and 40% were of the genotype PAV/AVI. Children of the genotype PAV/AVI were reported using more vegetables, but not berries, than the AVI/AVI children. The results also show that the liking scores of the children of the AVI/AVI, PAV/AVI, and PAV/PAV genotypes differed from each other, and that the familiarity of a berry product is likely to be an important factor in liking.

The hTAS2R38 genotype is associated with sugar and candy consumption in preschool boys

BACKGROUND The hTAS2R38 taste receptor genotype is related to bitter taste perception and thus may affect food preferences. The present study aimed to evaluate the relationship between the hTAS2R38 genotype and the food consumption and nutrient intakes of Finnish children aged 2-6 years. METHODS Dietary intake was assessed with 7-day food records, and DNA samples were collected by cheek swabs for genotyping. Food intake data between the three most common genotypes were compared (n = 345). RESULTS The proportion of the AVI/AVI genotype was 36.7%; PAV/AVI was 42.4%; and PAV/PAV was 14.9%. Boys with the PAV/PAV genotype consumed a mean (SD) weight of sugar and candy of 27 (13) g day(-1), which was significantly more compared to the other two genotypes [AVI/AVI 19 (12) g day(-1) and PAV/AVI 18 (12) g day(-1); both P < 0.01]. These boys also consumed significantly more meat (g day(-1)) compared to AVI/AVI boys (P < 0.05). PAV/PAV girls tended to consume more grains (g MJ(-1)) compared to AVI/AVI girls (P = 0.07). Vegetable and fruit consumption and nutrient intake did not differ significantly between genotypes. Based on principal component analysis carried out with total food consumption data, PAV/PAV boys were different from both AVI/AVI and PAV/AVI boys. CONCLUSIONS The hTAS2R38 genotype may have distinct associations with food consumption in boys and girls.

Impact of sensory-based food education in kindergarten on willingness to eat vegetables and berries

Background Children use all of their senses when exploring new foods, and sensory-based food education provides new possibilities for promoting healthy dietary habits. Objective To evaluate the effect of sensory-based food education activities on childrens willingness to eat test samples of selected vegetables and berries. Design Two kindergartens in Hanko, Finland, participated in the study and the subjects were children aged 3–6 years, divided in the intervention (n=44) and control (n=24) kindergarten. In the intervention kindergarten, five sensory-based food education sessions focusing on vegetables and berries were implemented, once per week for 5 weeks. A tasting protocol was performed with the children at baseline and after the intervention. The willingness to eat (5 different vegetables and 3 Finnish berries) was categorised. Parents also filled in a questionnaire on the childrens food preferences at home. Results In the intervention kindergarten, the willingness to eat the samples increased significantly (p≤0.001, Wilcoxon and Friedman), while in the control kindergarten, no significant change was observed when all of the test samples were taken into account. The parental report of their childrens preferences and childrens actual eating of the test samples corresponded relatively weakly. Conclusions Sensory-based food education activities may promote a willingness to eat vegetables and berries. Child-centred test methods are important for evaluating the effects of dietary interventions among children.

Chemical-Sensory Characteristics and Consumer Responses of Blackcurrant Juices Produced by Different Industrial Processes

Four blackcurrant juices were produced in industrial scale to study the impact of different processes on the sensory-chemical characteristics and hedonic responses of consumers. Two juices were produced without enzymatic treatment of berries with or without further clarification and filtration. The residue was re-pressed using an enzyme-aided processing method to yield the third juice. The forth juice was obtained by conventional enzymatic processing of berries. The enzyme-aided juices were more astringent and bitter than the non-enzymatic juices, mostly due to higher contents of phenolic compounds, lower contents of sugars, and lower pH and sugar/acid ratio. Higher degree of polymerisation and lower procyanidin/prodelphinidin ratio in proanthocyanidins also contributed to higher intensities of astringencies of the enzyme-aided juices. Overall, the non-enzyme-aided juices received higher ranking in flavour, the enzyme-aided juices in odour. Sweetness, roundness, berryness, and high-sugar content were positive drivers for liking, whereas astringency, bitterness and high content of phenolic compounds were negative drivers. High-pectin content masked the astringency and bitterness of the juices. Higher liking ratings correlated with the previous consumption of blackcurrants and higher age of consumers. Gender showed clear impact on consumer rating of the juices. Males liked more enzyme-aided juices than females and vice versa with the juices produced without the use of enzymes. The processes investigated by this study maybe optimised for commercial production of juices targeted for different consumer groups.