Evaluation of physicochemical, sensory, and antimicrobial properties of small-scale produced fruit vinegars

Hungarian fruit vinegars were characterised in terms of physicochemical attributes (total polyphenol content, antioxidant characteristics/FRAP, CUPRAC, ABTS/, ascorbic acid content, pH, total soluble solids), sensory profiles, and antimicrobial properties. Both compositional and sensory profiles showed distinct patterns depending on the type of vinegar (Tokaj wine, balsamic or apple) and the additional fruit used. Balsamic vinegars maturated on rosehip, sea buckthorn, and raspberry showed outstanding antioxidant performances. Rosehip, raspberry, and quince vinegars, as well as vinegars produced from Tokaji aszú and balsamic apple obtained high scores for fruity and sweet notes. Antimicrobial activities were tested on Gram-negative and Gram-positive organisms, including probiotic bacteria. Generally, only weak activities were obtained, which was attributed to the natural sugar content of the samples, depending on the type of the vinegar and the fruit. Similar results, but more pronounced bacterial growth inhibitions were obtained for probiotic strains, however, some probiotic strains were resistant to at least two of the vinegars. Based on these, balsamic apple, raspberry, rosehip, quince, and sea buckthorn may qualify as potential functional components of probiotic preparations containing some of the strains tested.

Effects of Soaking Tempe in Vinegar on Metabolome and Sensory Profiles

Tempe is a fermented soybean food that is globally renowned for its high protein content. Methods of preparing tempe vary worldwide, and include soaking in vinegar before fermentation. This study aimed to determine the effects of soaking in vinegar by metabolome analysis, gas chromatography/mass spectrometry, and sensory attribute evaluation. Vinegar affected metabolism during tempe fermentation, which led to altered metabolite profiles in the final product. We validated the metabolite profiles of two types of tempe using triangle tests and rate-all-that-apply (RATA) tests, which revealed that the sensory attributes of a golden-brown color, ammonia smell, pleasant smell, salty flavor, and acceptance significantly differed (p < 0.05) between the two types of tempe. A high concentration of specific amino acids in the control tempe explained a strong ammonia smell, saltiness, and darker golden-brown sensory attributes. Tempe soaked in vinegar contained high concentrations of metabolites associated with a roasted aroma and cooked meat. In conclusion, most RATA panelists who were being introduced to tempe preferred that soaked in vinegar to the control that was not.

Sensory Profiles of Chocolate Drinks Made from Commercial Fermented Cocoa Powder and Unfermented Cocoa Beans

Polyphenols are the major bioactive compounds of cocoa beans. The addition of unfermented cocoa beans powder is used to enhance the functional properties of the chocolate drink. This study aimed to analyze the sensory profile of chocolate drinks made from a mixture of commercial cocoa powder and non-fermented cocoa beans by the projective mapping method. Seventy-five naive panelists tested four types of chocolate drink formulations and one benchmark (BM). The beverage formulations based on commercial cocoa powder consist of Formulations 1 (F1), F2, F3, F4 namely with the addition of 0, 10%, 20%, and 30% unfermented cocoa powder, respectively. The result showed that samples F1, F2, F3, and F4 had the dominant attributes of chocolate aroma, bitter taste, and bitter aftertaste. Whereas, BM has a dominant sensory profile of chocolate aroma, sweet taste, and sweet aftertaste. The highest value elevation (95o) is the benchmark (commercial chocolate powder drink). The next height value is in sample F1 which is located at an altitude of 20o-30o. Samples F2, F3, and F4 are the samples that have the lowest elevation (20o). Thus, the addition of cocoa powder from unfermented cocoa beans has not been accepted by consumers due to its bitter taste and bitter aftertaste.

Non-Conventional Grape Varieties and Yeast Starters for First and Second Fermentation in Sparkling Wine Production Using the Traditional Method

Sparkling wine production using the traditional method involves a second fermentation of still wines in bottles, followed by prolonged aging on lees. The key factors affecting the organoleptic profiles of these wines are the grape varieties, the chemical and sensory attributes of the base wines elaborated, the yeast strains used for first and second fermentation, and the winery practices. While Chardonnay and Pinot noir are gold standard grape varieties in sparkling wine production, other valuable grape cultivars are used worldwide to elaborate highly reputable sparkling wines. Fundamental research on the chemical and sensory profiles of innovative sparkling wines produced by the traditional method, using non-conventional grape varieties and novel yeast strains for first and/or second fermentation, is accompanying their market diversification. In this review, we summarize relevant aspects of sparkling wine production using the traditional method and non-conventional grape varieties and yeast starters.

Sensory Specific Desires. The Role of Sensory Taste Exposure in Desire for Food with a Similar or Different Taste Profile

The present study investigated how the sensory taste profile of a meal altered the subjective desire, wanting and liking of foods with a sweet, salty, sour, bitter, fatty, and spicy sensory profile, respectively. Participants (n = 85) ate a meal with a pronounced sensory taste profile: (1) sweet, (2) salty, or (3) sweet and salty combined. Self-reports of appetite, pleasantness, and sensory specific desires (SSD) were evaluated over the course of the meal using VAS-scales. SSDs were further studied through alterations in liking and desire for food samples with the main sensory profile being sweet (peach), salty (pretzel), sour (green apple), bitter (dark chocolate), fatty (whipped cream), and spicy (chilli nut), respectively. Consumption of food with a pronounced sensory taste profile was found to suppress the desire for food with a similar sensory taste profile, while the desire for different sensory profiles were enhanced or not affected. Further, when exposed to two pronounced tastes within the same meal, suppression of sensory desires was not only specific for the exposure tastes but tended to go beyond the sensory exposure. The findings suggest that taste variation within a meal holds the potential to create more satisfying meals, which can hinder additional desires after a meal and thus, lower additional calorie intake.

Descriptive sensory analysis and acceptance of leaves of smooth and curly kale

ABSTRACT Curly and smooth kale hybrids grown in both field (conventional) and hydroponic systems were sensory-analyzed using the descriptive and affective sensory technique. The treatments comprised hydroponic-cultivated Darkibor (A), Darkibor cultivated in field (B), HS2O (C), Arielli (D) and Kobe (E), these last three cultivated under conventional system (field-cultivated). The panelists indicated the significant attributes that described the differences in kale sensory profiles. Darkibor (A) and Arielli (D) kale leaves had the lightest green color. Regarding their format, the kales were classified into smooth and curly. Both the Darkibor grown in field (B) and Arielli (D) had the most intense bitter taste. Darkibor (A) showed the highest intensity for sweet taste, followed by Arielli (D). The field-cultivated Darkibor (B) ranked the highest crispness and mouthfeel (sensation produced by a particular food in the mouth). The color and texture of the kale leaves affected purchase intention by the consumer, and the color showed a difference among the kales, with Darkibor kale (A) receiving the lowest score. Darkibor (A) obtained lower buying-likelihood scores, reinforcing that color affects consumers’ purchase intention.

Pre-processing Cooling of Harvested Grapes Induces Changes in Berry Composition and Metabolism, and Affects Quality and Aroma Traits of the Resulting Wine

Due to the greenhouse gas increase, grapes are often exposed to high temperatures in several growing areas especially during the final developmental stages, and this is particularly true when early ripening cultivars are harvested. This may cause undesirable effects on berry metabolism and composition and wine quality, particularly concerning the aroma profile. Harvesting at night or keeping the harvested grapes in cold rooms before vinification are empirical protocols applied in specific viticultural areas. To study the effects of decreasing berry temperature after harvest, white-skinned berries (cv Vermentino) were maintained at 4 or 10°C for 24 or 48 h before processing (pre-cooling). Control grapes were kept at 22°C. Grapes cooled at 10°C for 24 and 48 h resulted richer in polyphenols and showed a significant up-regulation of genes involved in polyphenols biosynthesis (i.e., VvPAL, VvSTS2, and VvFLS1). Similar behavior was observed in samples kept at 4°C for 48 h. Pre-cooling induced specific changes in the volatile organic compound (VOC) profiles. In particular, higher amounts of a specific subcategory of terpenes, namely sesquiterpenes, were detected in cooled samples. The induction of the expression of key genes involved in terpenoids biosynthesis (VvHDR, VvDX3, VvTER, VvGT14) was detected in cooled grapes, with variable effects depending on temperature and treatment duration. In both cooled samples, the evolution of alcoholic fermentation followed a regular trend but ended earlier. Higher phenolic content was detected in wines obtained from the 10°C-treated grapes. Higher residual concentration of malic acid at the end of fermentation was detected in wine samples from grapes pre-cooled at 4°C. Sesquiterpenes also showed a general increase in wines from cooled grapes, especially after pre-cooling at 10°C for 48 h. Different sensory profiles characterized the wine samples, with the best scores in terms of general pleasantness obtained by the wine produced from grapes pre-cooled at 4°C for 24 h. These results demonstrate that pre-cooling harvested grapes induces specific effect on the VOC profile and other quality parameters of Vermentino wine, and this appears to be the result of specific metabolic and compositional changes occurring in the berries.

The Use of Electronic Nose as Alternative Non-Destructive Technique to Discriminate Flavored and Unflavored Olive Oils

Cv. Arbequina extra virgin olive oils (EVOO) were flavored with cinnamon, garlic, and rosemary and characterized. Although flavoring significantly affected the physicochemical quality parameters, all oils fulfilled the legal thresholds for EVOO classification. Flavoring increased (20 to 40%) the total phenolic contents, whereas oxidative stability was dependent on the flavoring agent (a slight increase for rosemary and a decrease for cinnamon and garlic). Flavoring also had a significant impact on the sensory profiles. Unflavored oils, cinnamon, and garlic flavored oils had a fruity-ripe sensation while rosemary flavored oils were fruity-green oils. Fruit-related sensations, perceived in unflavored oils, disappeared with flavoring. Flavoring decreased the sweetness, enhanced the bitterness, and did not influence the pungency of the oils. According to the EU regulations, flavored oils cannot be commercialized as EVOO. Thus, to guarantee the legal labelling requirement and to meet the expectations of the market-specific consumers for differentiated olive oils, a lab-made electronic nose was applied. The device successfully discriminated unflavored from flavored oils and identified the type of flavoring agent (90 ± 10% of correct classifications for the repeated K-fold cross-validation method). Thus, the electronic nose could be used as a practical non-destructive preliminary classification tool for recognizing olive oils’ flavoring practice.

Introducing Tempeh as a New Plant-Based Protein Food Item on the Danish Market

Decreasing meat consumption has resulted in a need for new high-quality protein sources. Tempeh is relatively unknown in Denmark and might be capable of meeting this need. The aim of the study was to describe the success criteria for introducing locally produced tempeh and to investigate the sensory quality of three types of tempeh. Only 24% of the consumers in the survey (n = 395) used meat alternatives, which might be explained by a low level of satisfaction with availability. Tempeh was known by 26%—the less meat eaten, the greater the knowledge of tempeh. Twenty-three per cent of the consumers had positive attitudes towards tempeh. The three types of tempeh had markedly different sensory profiles. Nevertheless, the home use test showed that they could be used interchangeably in different recipes. In addition, the consumers were more positive about recipes in which tempeh did not resemble meat compared with meat-inspired recipes. In conclusion, introducing locally produced tempeh on the Danish market is possible but would require further knowledge of the product. In addition, tempeh should be sold as a tasty, high-quality protein food item in its own right. Recipes using tempeh should reflect this and not mimic meat recipes.