Quality Evaluation and Processing Suitability Analysis of Specialty Fresh Chili Peppers from Main Production Areas in China

In this study, the differences in quality among 24 distinctive varieties of chili peppers from seven main production areas in the northwest (Xinjiang, Inner Mongolia and Gansu), southwest (Yunnan and Guizhou) and mid-east (Shandong, Henan) regions of China were analyzed in terms of basic characteristics (seed-to-flesh ratio and flesh thickness), 10 physicochemical indexes of chili pepper flesh (including moisture, protein, soluble solids, glucose, crude fiber, ash, capsaicinoids, VC, total phenol contents, and hotness) and five quality indicators of chili pepper seeds (moisture, protein, crude fiber, ash, and fat contents), followed by comprehensive quality evaluation and processing suitability analysis. Cluster analysis results showed that the 24 varieties were divided into four types based on geographical origin and fruit shape. Type I included three chili varieties from Xinjiang, which, with low moisture content, thin flesh and high nutrient content, was suitable for the production of dried chili and chili extract and the comprehensive utilization of chili pepper seeds as a by-product. Type II included two finger-shaped varieties from Yunnan, which, with thin flesh, high pungency and moderate nutrient contents, was suitable for the production of dried or fermented chill products as well as spicy seasonings. Type III included varieties from the southwest region and Shandong, which, with high seed-to-flesh ratio and high contents of protein and crude fiber, was suitable for the production of dried chili, oil chili, hot pot base and fermented chili products and the comprehensive utilization of chili pepper seeds. Type IV included horn-shaped peppers from northwest China, which, with thick flesh low seed-to-meat ratio, was suitable for processing into fresh-cut peppers, quick-frozen peppers and fresh pepper paste/sauce. This study provides basic data for the establishment of an evaluation system for characteristic quality of raw chili peppers and the prediction of processing suitability.