Comprehensive fruit quality assessment and identification of aroma-active compounds in green pepper (Capsicum annuum L.)

Abstract

The wrinkled pepper (Capsicum annuum L.) is a type of chili pepper domesticated in northwestern China, with a characteristic flavor. Fifteen wrinkled and four smooth-skinned pepper varieties were evaluated for morphology, texture, color, nutrients, capsaicinoids, and volatile compounds at the mature fruit stage. The sensory evaluation showed wrinkled pepper was superior to smooth pepper in texture, and it has a highly significant correlation (p < 0.01) with cuticle thickness, maximum penetrating force, lignin content, and moisture content. Citric acid was the major organic acid in peppers, accounting for 39.10–63.55% of the total organic acids, followed by quininic acid. The average oxalic acid content of smooth peppers was 26.19% higher than that of wrinkled peppers. The pungency of wrinkled pepper fruits ranged from 1748.9 to 25529.4 SHU, which can be considered slightly to very spicy, while the four smooth varieties ranged between 866.63 and 8533.70 SHU, at slightly to moderately spicy. A total of 199 volatile compounds were detected in the 19 pepper varieties. The average volatile content of wrinkled pepper was 39.79% higher than that of smooth pepper. Twenty-nine volatile compounds, including 14 aldehydes, four alcohols, three esters, three ketones, two furans, one pyrazine, one acid, and one phenol, contributed to the fragrance of peppers and could be regarded as aroma-active compounds, with 2-isobutyl-3-methoxypyrazine being the major contributor among the 19 pepper varieties. Wrinkled pepper can be confidently distinguished from smooth pepper and is of superior quality. The current findings outlined the major texture-related characteristics of pepper as well as the main aroma-active compounds, providing valuable information for pepper quality breeding and consumer guidelines.

Phytonutritional and Sensorial Assessment of a Novel Functional Beverage Formulated from an Underutilized Fruit of Carissa spinarum L

“…Color, flavor, taste, and acceptability also showed weak or no correlation with pH, RS, total sugars, TPC, and antioxidants. The use of heat maps for quality assessment and optimization of juice generation from fruit samples has been previously well reported. ,, In a previous study, Zhang et al . generated a heat map through Pearson correlation analysis to comprehensively assess fruit quality and identify aroma-active compounds in green pepper.…”

“…The use of heat maps for quality assessment and optimization of juice generation from fruit samples has been previously well reported. 37,66,67 In a previous study, Zhang et al 67 generated a heat map through Pearson correlation analysis to comprehensively assess fruit quality and identify aroma-active compounds in green pepper. Their research findings elucidated the primary texture-related attributes of pepper and identified the key aroma-active compounds, thereby offering valuable insights for improving pepper quality through breeding programs and establishing consumer guidelines.…”

Piquin chili, a wild spice: natural variation in nutraceutical contents

“…In chili, this category includes a heterogeneous group of chemical compounds ( Figures 1D , E ) responsible for aroma and partial flavor, which influences the organoleptic perceptions of consumers and criteria for specific uses ( 67 , 68 ). They are organic, low molecular weight compounds, and volatile at environmental temperatures ( 69 ).…”

“…In Capsicum species, several chemical groups have been reported, including aldehydes, organic acids, esters, lipoxygenase cleavage products, nitrogen-containing compounds, hydrocarbons, alcohols, ketones, furans, terpenoids, phenolics, and miscellaneous compounds, highlighting the complexity of volatile compounds in these fruits. However, not all compounds contribute to the aroma, and chemical diversity fluctuates between species, varieties, and phenology ( 68 , 70 ). Piquin chili is also preferred by consumers due to its aromatic traits, especially in the green stage, with fresh, fruity, and herbal notes, which are associated with its complex chemical array.…”

Characterization of key aroma compounds of fried pepper sauce under different pretreatment processes

“…2 China leads in chili pepper production and consumption, contributing to half of the total global production in 2019. 3 Chili peppers hold significant importance in Chinese culinary culture, commonly consumed fresh as a standalone vegetable or used as a condiment to enhance aroma and presentation in dishes. 4,5 However, their high moisture content renders fresh peppers unsuitable for prolonged storage, 6 leading to their transformation into various capsicum products such as fermented chili peppers, pickled peppers, and fried pepper sauce (FPS).…”