Characteristic aroma analysis of finger citron in four different regions based on GC-MS-HS-SPME and ROAV

Finger citron (Citrus medica L. var. sarcodactylis Swingle), a type of citrus with high ornamental and medicinal values, were used as raw material for beverage and wine making. Depends on the origin, the key aroma compounds of the fruit may vary. The aim of this study is to identify interspecific differences in finger citron and to provide a reference for the evaluation of finger citron fruit flavor, variety improvement and selection of new varieties. In the present study headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) were used to analyze and identify the volatiles of 4 different varieties of finger citron from four different locations (Zhejiang, Guangzhou, Yunnan and Sichuan). Their similarities and differences were further analyzed by Venn diagram. The relative odor activity value (ROAV), heat map, radar map and partial least squares regression (PLSR) were used to determine the key volatiles of finger citron. The results showed that 68 volatiles were detected in different varieties of finger citron, among which 16 key volatiles had ROAV >= 1. Geraniol and d-limonene had a greater influence on the aroma of finger citron. The main aroma of finger citron in the four regions was the citrus aroma. ZFC had the most abundant flavor, with obvious woody and herbal flavors, which was suitable for the breeding of finger citron with partial herbal flavor. GFC was suitable for breeding finger citron which was on the sweet side. Compared with SFC, YFC was more suitable for breeding finger citron with floral flavor. This study mainly investigates the flavor differences of different varieties of finger citron to provide theoretical support for the subsequent product development. Novelty Impact Statement This study found that finger citron from Zhejiang, Sichuan, Guangdong, and Yunnan provinces in China had different aroma characteristics. The odor of finger citron from Guangdong was sweet, the odor of finger citron from Zhejiang was more herbal, and the odor of finger citron from Yunnan and Sichuan was more floral. This provided a theoretical basis for the subsequent application and breeding of finger citron.