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The compositional authentication of wine is of great interest, as the geographic origin of the grapes is often associated with quality, uniqueness, and authenticity. Previous elemental fingerprinting studies mainly discriminated wines from different countries or regions within a country. Here, we report the use of element profiles to distinguish commercial Pinot noir wines from five sub-regional appellations or neighborhoods within one American viticultural area (AVA). Fifty-three single cultivar wines were collected over two harvests and analyzed using microwave plasma-atomic emission spectroscopy (MP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS). Of 62 monitored elements that were quantified with fully validated methods, 24 and 32 elements differed significantly across the neighborhoods and vintages, respectively (p < 0.05). Targeted canonical variate analysis (CVA) explained 85%-90% of the variance ratio across the two vintages, indicating persistent and stable elemental fingerprints of wines at a sub-regional level. A sixth, newly founded neighborhood was correctly grouped separately from the others using a Soft Independent Modeling of Class Analogy (SIMCA), indicating the potential of elemental fingerprints for wine authenticity.

Wine elemental composition varies by cultivar, geographic origin, viticultural and enological practices, and is often used for authenticity validation. Elemental analysis of wine by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is challenging due to the potential for non-spectral interferences and plasma instability arising from organic matrix components. Sample preparation mitigates these interferences, however, conflicting recommendations of best practices in ICP-MS analysis of wine have been reported. This study compared direct dilution, microwave-assisted acid digestion, and two filtration sample pretreatments, acidification prior to filtration and filtration followed by acidification, in elemental profiling of one white and three red table wines by ICP-MS. Of 43 monitored isotopes, 37 varied by sample preparation method, with significantly higher results of 17 isotopes in the microwave-digested samples. Both filtration treatments resulted in lower results for 11 isotopes compared to the other methods. Finally, isotope dilution determination of copper based on natural abundances and the 63Cu:65Cu instrument response ratio agreed with external calibration and confirmed a significant sample preparation effect. Overall, microwave digestion did not compare favorably, and direct dilution was found to provide the best compromise between ease of use and result accuracy and precision, although all preparation strategies were able to differentiate the wines.

Grapevine red blotch-associated virus (GRBaV) is a major threat to the wine industry in the USA. GRBaV infections (aka red blotch disease) compromise crop yield and berry chemical composition, affecting the flavor and aroma properties of must and wine. In this study, we combined genome-wide transcriptional profiling with targeted metabolite analyses and biochemical assays to characterize the impact of the disease on red-skinned berry ripening and metabolism. Using naturally infected berries collected from two vineyards, we were able to identify consistent berry responses to GRBaV across different environmental and cultural conditions. Specific alterations of both primary and secondary metabolism occurred in GRBaV-infected berries during ripening. Notably, GRBaV infections of post-véraison berries resulted in the induction of primary metabolic pathways normally associated with early berry development (e.g. thylakoid electron transfer and the Calvin cycle), while inhibiting ripening-associated pathways, such as a reduced metabolic flux in the central and peripheral phenylpropanoid pathways. We show that this metabolic reprogramming correlates with perturbations at multiple regulatory levels of berry development. Red blotch caused the abnormal expression of transcription factors (e.g. NACs, MYBs, and AP2-ERFs) and elements of the post-transcriptional machinery that function during red-skinned berry ripening. Abscisic acid, ethylene, and auxin pathways, which control both the initiation of ripening and stress responses, were also compromised. We conclude that GRBaV infections disrupt normal berry development and stress responses by altering transcription factors and hormone networks, which result in the inhibition of ripening pathways involved in the generation of color, flavor, and aroma compounds.

Despite its importance as an undesirable food texture, the phenomenon of chalkiness remains understudied. Chalky sensations presumably arise from fine particulates found in foods, but semantic overlap with other common descriptors of small particles, like gritty or sandy, is unclear. Here, we compare the usage of Chalky with related descriptors, and determine the effect of particle size, concentration, and xanthan content on Chalky ratings in a model beverage. A 23 factorial design with starch particle size (D90 = 33.8 and 64.6 µm), starch concentrations (10 and 20% w/v), and xanthan content (0.075 and 0.15% w/v) was used. Participants' salivary flow rate was also assessed. A multi-sip taste test was performed where naïve consumers (n = 82; 39% men, 60% women; age range = 18–79 years) rated the intensity of Chalky, Powdery, Gritty, Sandy, Mouthdrying, and Residual mouthcoating at 0, 30, and 60 s after each of three consecutive sips. All attribute ratings were highly correlated, with Chalky, Powdery, and Residual Mouthcoating being more closely correlated with each other than Gritty or Sandy. Although Chalky was still reported 60 s after consumption, no evidence of build-up was found with repeated sips. A larger size and higher concentration increased Chalky ratings, with the low-salivary-flow group reporting greater ratings for Chalky relative to the high-flow group. Our results suggest consumer percepts of small particles are overlapping but not entirely redundant. This suggests researchers and product developers should carefully distinguish between these descriptors when trying to understand consumer perception of food products containing fine particles. [ABSTRACT FROM AUTHOR]

The Teruel Orthorexia Scale (TOS) defines two related but distinct constructs: Orthorexia Nervosa (OrNe), a pathological fixation on a healthy diet, and Healthy Orthorexia (HeOr), an interest in a healthy diet independent of psychopathology. Here, we (a) assessed both types of Orthorexia in a large North American sample using the TOS and (b) explored if engaging in regular physical activity was associated with a greater risk of Orthorexia. A cohort of physically active adults (n = 927; 41% men) completed the TOS, as well as the Rapid Assessment of Physical Activity (RAPA), to broadly assess aerobic physical activity level and participation in strength and/or flexibility training. As expected, scores for HeOr and OrNe differed between participants, with lower scores for Orthorexia Nervosa in our physically active non-clinical sample. Higher HeOr scores were associated with lower BMI, and this was true for both men and women. We also found that measures of Orthorexia were associated with self-reported physical activity: active adults reporting more aerobic physical activity had higher HeOr scores, with the most active men having the highest scores. Notably, adults who reported regular strength training had higher scores for both HeOr and OrNe, with men who strength trained showing higher OrNe scores than women. Here, those who participate in regular strength training are more likely to exhibit orthorexic behaviors, and this effect was more pronounced for men than women. Prior work has validated the TOS in young, primarily female samples of non-English speakers outside the United States: present data from an age-diverse, physically active, gender balanced sample support the use of TOS for measurement of Orthorexia Nervosa and Healthy Orthorexia in English speakers and suggest that more work is needed to assess potential gender differences in these constructs. [ABSTRACT FROM AUTHOR]

Differential sensing using synthetic receptors as mimics of the mammalian senses of taste and smell is a powerful approach for the analysis of complex mixtures. Herein, we report on the effectiveness of a cross-reactive, supramolecular, peptide-based sensing array in differentiating and predicting the composition of red wine blends. Fifteen blends of Cabernet Sauvignon, Merlot and Cabernet Franc, in addition to the mono varietals, were used in this investigation. Linear Discriminant Analysis (LDA) showed a clear differentiation of blends based on tannin concentration and composition where certain mono varietals like Cabernet Sauvignon seemed to contribute less to the overall characteristics of the blend. Partial Least Squares (PLS) Regression and cross validation were used to build a predictive model for the responses of the receptors to eleven binary blends and the three mono varietals. The optimized model was later used to predict the percentage of each mono varietal in an independent test set composted of four tri-blends with a 15% average error. A partial least square regression model using the mouth-feel and taste descriptive sensory attributes of the wine blends revealed a strong correlation of the receptors to perceived astringency, which is indicative of selective binding to polyphenols in wine.

Twenty-seven commercial Californian Cabernet Sauvignon wines of different quality categories were analyzed with sensory and chemical methods. Correlations between five quality proxies-points awarded during a wine competition, wine expert scores, retail price, vintage, and wine region-were correlated to sensory attributes, volatile compounds, and elemental composition. Wine quality is a multi-faceted construct, incorporating many different layers. Depending on the quality proxy studied, significant correlations between quality and attributes, volatiles and elements were found, some of them previously reported in the literature.

The human nose is a very sensitive detector and is able to detect potent aroma compounds down to low ng/L levels. These levels are often below detection limits of analytical instrumentation. The following laboratory exercise is designed to compare instrumental and human methods for the detection of volatile odor active compounds. Reference standards of 3-mercapto-1-hexanol (3MH), a secondary thiol that is important to food quality, are analyzed by gas chromatography with flame ionization detection (GC-FID), and these raw data are provided to students. Students also perform a series of 3-alternative forced choice (3-AFC) sensory tests to determine the human detection limits in a series of samples. For both data sets, 2 methods of data analysis (standard deviation of the response and the slope and signal-to-noise ratio for GC-FID data; forced-choice ascending concentration series method of limits and linear regression for 3-AFC data) will be used to estimate instrumental detection limits and human thresholds. GC-FID and 3-AFC results are then compared by the students to demonstrate the importance of instrumental and human methods for food analysis, and to provide an experiential learning opportunity to critically think through multiple methods of analysis and compare the outcomes of those methods. In completing the laboratory exercise and discussion questions, students will gain an understanding of the advantages and disadvantages of human and instrumental measurements in food analysis, and compare the outcome of common data analysis methods for instrumental and sensory data.

Dark chocolate is a complex food defined by its unique flavor, taste, mouthfeel, and melting properties. The craft chocolate market is a new segment of the US confectionery industry that highlights cocoa bean origin by making two‐ingredient dark chocolate composed of cocoa liquor and sugar. To study the impact of natural variance in fat levels inherent to unblended cocoa liquor in two‐ingredient chocolate, we made 70% cacao dark chocolate from cocoa liquor reconstituted from cocoa powder and cocoa butter at total fat contents of 30%, 35%, and 40% (w/w), and collected sensory and acceptability data from 108 regular chocolate consumers. Increasing fat content did not significantly affect liking (p >.05). However, with increasing fat levels, perceived intensities of bitter taste, cocoa flavor, and drying mouthfeel significantly decreased, and sweet taste perception significantly increased (p <.05). Consumer chocolate preference (milk vs. dark) significantly affected perceived intensity of drying mouthfeel. Practical Applications: Our research suggests that liking of astringent stimuli may result in decreased perception of astringency in highly astringent foods. Further research is recommended to understand this mechanism as well as the physical and chemical underpinnings by which fat content impacts sensory perception of dark chocolate. [ABSTRACT FROM AUTHOR]

The elemental composition of red wine was studied with inductively coupled plasma--mass spectrometry (ICP-MS). The impact of storage and packaging as well as the role of geographic origin on the [...]

The quality of hops is dictated in large part by the content of flavor and aroma compounds. These compounds vary in concentration and are affected by agricultural practices. Previous research has found that the application of Bordeaux Mixture may impact the aroma quality of hops by altering concentrations of varietal thiols. The impact of copper fungicides other than Bordeaux Mixture and in hop production areas outside of the Pacific Northwest in the United States has yet to be evaluated. Herein we study the effects of application frequency of a copper (II) hydroxide fungicide on markers of hop quality in hops grown in the Northeastern United States. Copper fungicide application was found to significantly increase the total copper content of hop cones, regardless of application frequency; however, traditional markers of hop quality, including yield, essential oil composition, and acid content, were not affected. Beer consumers were unable to discriminate between beers dry-hopped with conventional or copper-treated hops based on aroma but were able to discriminate based on in-mouth perception. These findings suggest that the use of copper (II) hydroxide for the mitigation of fungal pathogens in hops grown in the Northeastern United States is unlikely to adversely affect final hop yield, acid content, or thiol quality. [ABSTRACT FROM AUTHOR]