Volatile Metabolites to Assess the Onset of Chilling Injury in Fresh-Cut Nectarines

Fresh-cut processing is a good strategy to enhance the commercialization of peaches and nectarines, which easily deteriorate during low-temperature storage mostly due to the occurrence of chilling injury. Although several studies have been performed to improve the shelf-life of fresh-cut stone fruit, the achievement of high-quality fresh-cut peaches and nectarines still constitutes a challenge. The present study aimed to gain insights into the evolution of the postharvest quality of fresh-cut nectarines (Prunus persica L. Batsch) Big Bang, cold-stored at two different storage temperatures (4 and 8 °C) for up to 10 days. Several aspects influencing the quality traits (sensory and postharvest quality parameters; the profile of phenolic and volatile organic compounds (VOCs)) were explored to predict the marketable life of the fresh-cut nectarines. The respiration rate was higher in samples stored at 4 °C, while the browning process was more evident in fruit stored at 8 °C. Partial Least Squares Regression performed on VOCs showed that samples stored at 4 °C and 8 °C presented a different time evolution during the experiment and the trajectories depended on the interaction between time and temperature. Moreover, Multiple Linear Regression analysis discovered that the 17 VOCs affected by the storage conditions seemed to suggest that no chilling injury was detected for nectarines Big Bang. In conclusion, this approach could also be used with other nectarine cultivars and/or different stone fruits.

Bioaccessibility and antioxidant capacity of phenolic compounds during shelf life of a new functional vegetable mix

Fresh-cut vegetables are minimally processed healthy products that have gained the preference of consumers in accordance to the current lifestyle. Fresh-cut industry is continuously evolving and pursuing new varieties of raw material to develop innovative vegetable products, which fulfil consumer expectations. The current study evaluated the phenolic compounds in an innovative vegetable mix (red cabbage, rocket, parsley and beet greens) as well as their antioxidant capacity and bioaccessibility during their shelf life under refrigerated storage. The initial total phenolic compound and flavonoids content in the salad mixture were 163.3 ± 5.77 mg GAE/100 g FW and 280.96 ± 25.14 mg QE/100 g FW, respectively. The initial antioxidant capacity in the salad mixture was 85.4 ± 7.9 mg TE/100 g FW for DPPH and 318.1 ± 26.5 mg TE/100 g FW for ABTS assays. After digestion, total phenolic compound and TEAC capacity at initial times showed percentage of recovery values close to the chemical extraction and suffered a decrease towards day 10 of storage. Flavonoids and DPPH capacity showed recovery percentages less than 50%, at all storage times. Regarding sensory quality, the shelf-life of the salad mixture was limited by the presence of unacceptable off-odors at day 7 but since at microbiological evaluation, the shelf-life of the product is no longer than 5 days.

Consumer acceptance of watermelon flesh-rind blends and the effect of rind on refreshing perception

Watermelon flesh is widely consumed for its appealing flavor and refreshing properties, though the rind of the fruit also has traits of interest, especially its nutritional benefits. This study aimed to determine if watermelon flesh blended with 0%, 10%, 20%, and 30% w/w rind could appeal to consumers, and the effect of rind on the refreshing perception was investigated. Consumers (n = 102) evaluated the liking and intensity levels of overall flavor, sweet, sour, green, watermelon flavor, and refreshing quality along with questions regarding the texture, off flavors, and aftertaste of the samples. The addition of rind was acceptable up to the 20% rind level, which was given an overall rating above the midpoint of the scale, while the 10% and 0% rind samples did not differ significantly (P < 0.001). Overall liking most strongly correlated with sweet liking (r = 0.78, P < 0.001) and watermelon flavor liking (r = 0.77, P < 0.001). Refreshing liking most strongly correlated with watermelon flavor liking (r = 0.75, P < 0.001) and decreased with addition of rind in the samples (P < 0.001). The excessive green notes, off flavors, and undesirable texture of rind decreased the hedonic and refreshing ratings of samples with 20% and 30% rind, respectively. This research demonstrated the acceptability of using up to 20% rind to supplement watermelon juice blends and results suggested that watermelon flavor drives the refreshing perception. PRACTICAL APPLICATION: These findings exhibit the diversity in consumer preferences for watermelon flesh blended with rind using a consumer test. The refreshing properties of watermelon flesh as related to sweetness and watermelon flavor, along with the flavor and mouthfeel attributes contributed by watermelon rind, are highlighted. Manufacturers of fruit-based beverages can apply this research to inform development of refreshing products, watermelon flavored products, or products that utilize rind waste.