Identification of Light-Induced Key Off-Flavors in Ponkan Mandarin Juice Using MDGC-MS/O and GC–MS/PFPD

Abstract

Light-induced off-flavor compounds in Ponkan mandarin juice were investigated during its shelf-life by headspace solid-phase microextraction multidimensional gas chromatography−mass spectrometry/olfactometry (MDGC-MS/O) and a GC− MS/pulsed flame photometric detector (GC−MS/PFPD). A total of 34 aroma-active compounds with flavor dilution (FD) factors from 2 to 128 were tentatively identified by aroma extract dilution analysis-MDGC-MS/O. Among them, a light-induced off-flavor compound with a high FD factor, methional (cooked potato), was positively identified in the Ponkan mandarin juice at the end of the shelf-life. In addition, 11 volatile sulfur compounds (VSCs), including 6 screened shelf-markers (variable identification, VID > 0.80), were identified in Ponkan mandarin juice by a sulfur detector (PFPD). Four VSCs exhibited odor activity values exceeding 1. Three VSCs (methanethiol, dimethyl trisulfide, and methional) were confirmed as key light-induced off-flavor compounds in Ponkan mandarin juice based on addition/omission experiments. Furthermore, light irradiation accelerated the degradation of sulfur precursors (methionine and MMS) and the formation of these VSCs leading to an increase in off-flavor intensity.

Role of Sulfur Compounds in Vegetable and Mushroom Aroma

“…Sulfides play a crucial role in the creation of organoleptic properties of food, which is why many synthetic sulfides are commonly used as food flavors (more than 80 mono-, di-, and polysulfides) and additives in processed foodstuff [60]. Sulfides are also associated with the off-flavors of many other products, such as drinking water, alcoholic beverages, and juices [80][81][82][83]. The sensory properties of sulfides are similar to each other because these compounds are most often characterized by a pungent smell and a spicy taste [26,84,85].…”

Comprehensive quality evaluation of fermented‐steaming Fructus Aurantii based on chemical composition, flavor characteristics, and intestinal microbial community

“…The aroma characteristics of D‐limonene are citrus, lemon, and minty. Pseudolimonene and γ‐terpinene with citrus‐like notes, α‐pinene with resin, pine, and ethereal notes also contributed a certain aroma to PFA (Cheng et al., 2021). Compared with the original FA, pseudolimonene was detected in the processed samples, which had the lime‐like flavor to give the PFA a richer odor expression.…”