No abstract

Cucumber is an economically important vegetable crop worldwide, but limited work has been done on consumer acceptance of freshly consumed cucumbers and associated physicochemical characteristics. This study aimed to investigate consumer acceptability of eight cucumber varieties representing different market groups, the correlation between their sensory quality and physiochemical properties (firmness, °Brix, pH, and TA), and the impact of variety and harvest date. Consumer (n = 206) test results indicated that the overall acceptance was correlated positively to the acceptability of overall texture, taste, and aroma (specifically juiciness intensity and fresh, green aroma), but negatively to sourness taste, bitterness taste, astringency, and off-flavors. Fruit firmness (placenta, flesh, peel/flesh border, and peel) from instrumental analyses were correlated positively to sensory crispiness and negatively to juiciness texture. °Brix, pH, and TA (titratable acidity) measurements did not correlate to cucumber sweetness and sourness tastes. Three most acceptable varieties were attributed to their freshness, aroma, and juiciness texture, while two least acceptable ones were due to their bitterness, astringency, and off-notes. Significant differences (p ≤ 0.05) in both consumer acceptance and physicochemical parameters from fruits harvested at different dates were identified. The findings provide new insights into consumer attitude and potential impactful factors, facilitating cucumber breeding for fruit quality improvement.

Mushroom has the potential to partially substitute egg white with increased flavor and nutrients. This study quantified 36 taste-related substances in 16 developed blends, in which egg whites were partially replaced with white and crimini mushrooms (0%, 10%, 20%, and 30%) followed by oven roasting or steaming. EZ:faast gas chromatography–mass spectroscopy was used to quantify 20 free amino acids, while high performance liquid chromatography–UV was used to determine five 5′-nucleotides, six sugars, and five organic acids. Egg white contained limited amounts of all these compounds, which significantly increased (p ≤ 0.05) in the egg white–mushroom blends. When egg whites were substituted with 30% mushrooms, total free amino acids, 5′-nucleotides, soluble sugars, and organic acids reached 5.4–10.1, 2.6–3.7, 53.5–106, and 0.5–2.9 mg/g dry matter, respectively, which increased 260–510, 4.0–6.5, 12–79, and 2.4–4.2 times compared to egg white alone. The majority of these quantified compounds varied along with mushroom varieties (white and crimini) and cooking methods (steam and roast). The blends were mainly differentiated by the mushroom proportions-associated 30 taste-related compounds according to principal component analysis (filtered with compounds cos2 < 0.5). These results demonstrate the contribution of mushroom taste-related compounds to egg white flavor and associated impact factors, providing evidence to increase future mushroom utilization in food product development.

Watermelon rind is treated as agricultural waste, causing biomass loss and environmental issues. This study aimed to identify free amino acids and volatiles in watermelon rind, flesh, and rind-flesh juice blends with ratios of 10%, 20%, and 30%. Among the 16 free amino acids quantified, watermelon rind alone contained higher total amino acids (165 mg/100 g fresh weight) compared to flesh alone (146 mg/100 g). The rind had significantly higher (1.5×) and dominant amounts of citrulline and arginine (61.4 and 53.8 mg/100 g, respectively) than flesh. The rind, however, contained significantly lower amounts of essential amino acids. Volatile analysis showed that watermelon rind total volatiles (peak area) comprised only 15% of the flesh volatiles. Of the 126 volatiles identified, the rind alone contained 77 compounds; 56 of these presented in all five samples. Aldehydes and alcohols were most prevalent, accounting for >80% of the total volatiles in all samples. Nine-carbon aldehyde and alcohol compounds dominated both the flesh and rind, though the rind lacked the diversity of other aldehydes, alcohols, ketones, terpenes, terpenoids, esters and lactones that were more abundant in the watermelon flesh. Watermelon rind was characterized by the major aroma compounds above their thresholds, including 17 aldehydes and six unsaturated nine-carbon alcohols. This study demonstrated the potential for rind as a food or beverage supplement due to its key features such as concentrated citrulline and arginine, relatively low odor intensity, and valuable volatiles associated with fresh, green, cucumber-like aromas.

This study aimed to characterize mechanical properties of five pecan oils and one olive oil using a texture analyzer compared to a rotational viscometer; the results were linked to fatty acid profile and total polyphenol content. The seven texture parameters (firmness, consistency, cohesiveness, viscosity index, and stickiness at 5 s, stickiness at 30 s, and delta stickiness) showed significant difference (p ≤.05) among the six oils. Overall, olive oil had higher texture analysis values and significantly higher rotational viscosity than pecan oils. Chemically, C18 fatty acids accounted for approximately 90% of the total fatty acids in the five pecan oils. Olive oil had a higher amount of long-chain, unsaturated fatty acids. Total polyphenols in pecan oils were 8-15 mg gallic acid equivalent (GAE)/100 g, while olive oil contained 27.2 mg GAE/100 g. Correlation analysis demonstrated a significant, positive relationship between "consistency" texture and rotational viscosity measurement.Mechanical properties (seven texture parameters and rotational viscosity) were partially correlated to fatty acid profile, though no universal pattern was identified.