Fresh strawberries (Fragaria x ananassa) are valued for their characteristic red color, juicy texture, distinct aroma, and sweet fruity flavor. In this study, genetic and environmentally induced variation is exploited to capture biochemically diverse strawberry fruit for metabolite profiling and consumer rating. Analyses identify fruit attributes influencing hedonics and sensory perception of strawberry fruit using a psychophysics approach. Sweetness intensity, flavor intensity, and texture liking are dependent on sugar concentrations, specific volatile compounds, and fruit firmness, respectively. Overall liking is most greatly influenced by sweetness and strawberry flavor intensity, which are undermined by environmental pressures that reduce sucrose and total volatile content. The volatile profiles among commercial strawberry varieties are complex and distinct, but a list of perceptually impactful compounds from the larger mixture is better defined. Particular esters, terpenes, and furans have the most significant fits to strawberry flavor intensity. In total, thirty-one volatile compounds are found to be significantly correlated to strawberry flavor intensity, only one of them negatively. Further analysis identifies individual volatile compounds that have an enhancing effect on perceived sweetness intensity of fruit independent of sugar content. These findings allow for consumer influence in the breeding of more desirable fruits and vegetables. Also, this approach garners insights into fruit metabolomics, flavor chemistry, and a paradigm for enhancing liking of natural or processed products.

Breeding for a subjective goal such as flavor is challenging, as many blueberry cultivars are grown worldwide, and identifying breeding targets relating to blueberry flavor biochemistry that have a high degree of genetic control and low environmental variability are priorities. A variety of biochemical compounds and physical characters induce the sensory responses of taste, olfaction, and somatosensation, all of which interact to create what is perceived flavor. The goal of this study was to identify the flavor compounds with a larger genetic versus environmental component regulating their expression over an array of cultivars, locations, and years. Over the course of three years, consumer panelists rated overall liking, texture, sweetness, sourness, and flavor intensity of 19 southern highbush blueberry (Vaccinium corymbosum hybrids) genotypes in 30 sensory panels. Significant positive correlations to overall liking of blueberry fruit (P<0.001) were found with sweetness (R2 = 0.70), texture (R2 = 0.68), and flavor (R2 = 0.63). Sourness had a significantly negative relationship with overall liking (R2 = 0.55). The relationship between flavor and texture liking was also linear (R2 = 0.73, P<0.0001) demonstrating interaction between olfaction and somatosensation. Partial least squares analysis was used to identify sugars, acids, and volatile compounds contributing to liking and sensory intensities, and revealed strong effects of fructose, pH, and several volatile compounds upon all sensory parameters measured. To assess the feasibility of breeding for flavor components, a three year study was conducted to compare genetic and environmental influences on flavor biochemistry. Panelists could discern genotypic variation in blueberry sensory components, and many of the compounds affecting consumer favor of blueberries, such as fructose, pH, β-caryophyllene oxide and 2-heptanone, were sufficiently genetically controlled that allocating resources for their breeding is worthwhile.

No abstract

Blueberries are a high-value fruit that has experienced extraordinary growth in consumption in the past decade. Maintaining this growing market requires an understanding of the current market and its potential for expansion. To assay the impact of 36 specific blueberry sensory and psychological traits on consumer interest, a blueberry fruit quality study was constructed using techniques that allow many features to be tested in an analysis by combining specifics from different categories that describe a product. Individual traits that most impact the likelihood of fruit purchase were identified. Sweet and intense blueberry flavor yielded the most positive purchase interest, whereas bad texture attributes such as seediness were the most detrimental to interest. It was also possible to define two interest segments within the survey population that shared similar responses to particular experimentally assayed traits. The larger segment of the sample population (61%) was most interested in the aspects of blueberry flavor, whereas the second segment of respondents (39%) was most influenced by health aspects commonly associated with blueberry fruit consumption. Both segments responded negatively to bad texture. This study suggests that breeders and producers should exploit genetic and environmental variables that contribute to improved blueberry flavor and that marketing strategies to sell blueberry cultivars of superior flavor may be appropriate.

Previously, when selecting for flavor in the University of Florida southern highbush blueberry (SHB, Vaccinium corymbosum L. hybrids) breeding program, sugar/acid ratios and breeder preference were the only factors considered. A more precise method of evaluating flavor would include volatile compounds that may also contribute to the flavor experience. Therefore, volatile profiles of five SHB cultivars (Farthing, FL01-173, Scintilla, Star, and Sweetcrisp) were compared using gas chromatography–mass spectrometry. All cultivars were harvested on four separate dates within the harvest season, and fruit from each cultivar were also harvested at four developmental stages on the first harvest date. Among the cultivars, soluble solids content and volatile production tended to increase with fruit maturity, whereas titratable acidity decreased. All volatile components were more variable than measures of sugars and acids during the harvest season. Many of the volatiles present varied significantly between harvest dates, resulting in significant genotype × environment interactions during the harvest season. A closer examination of linalool, trans-2-hexenol, trans-2-hexenal, hexanal, and 1-penten-3-ol, five volatile compounds commonly associated with blueberry flavor, showed cultivar, developmental stage, and harvest date differences for each volatile. ‘Star’ experienced the least variation through the harvest period.