Cider flavor has a very important impact on the quality. Solid-phase microextraction-gas chromatography–mass spectrometry (SPME-GC-MS) combined with gas chromatography–ion mobility spectrometry (GC-IMS) tested different kinds of non-Saccharomyces yeasts and Saccharomyces cerevisiae (S. cerevisiae) co-inoculated for the fermentation of cider to determine differences in aroma material, and the determination of odor activity value (OAV) is applied less frequently in research. Through Rhodotorula mucilaginosa, Debaryomyces hansenii, Zygosaccharomyces bailii, and Kluyveromyces Marxianus, four different strains of non-Saccharomyces yeast fermented cider, and it was found that, in both the chemical composition and flavor of material things, compared with monoculture-fermented cider using S. cerevisiae, all differences were significant. Co-inoculated fermentation significantly improved the flavor and taste of cider. As in the volatile compounds of OVA > 1, octanoic acid (Sc 633.88 μg/L, co-inoculation fermented group 955.49 μg/L) provides vegetable cheese fragrance and decanoic acid, ethyl ester (Sc 683.19 μg/L, co-inoculation fermented group 694.98 μg/L) a creamy fruity fragrance, etc., and the average content increased after co-inoculated fermentation. Phenylethyl alcohol, which can produce a rose scent, was relatively abundant in cider samples and varied greatly among the groups. Moreover, the contents of ethyl lactate and 1-butanol in the Sc+Rm (ciders fermented by S. cerevisiae and R. mucilaginosa) were the highest of all of the cider samples. Different types of non-Saccharomyces yeast produced cider with different flavor characteristics. This study demonstrates that different species of non-Saccharomyces yeast do have an important impact on the characteristics of cider and that co-inoculation with non-Saccharomyces yeast and S. cerevisiae for cider fermentation may be a strategy to improve the flavor of cider.
Soybean oil heating or cooking is a very complicated process. In order to better understand the composition of the volatile compounds from soybean oil during heating process, volatile profiling was carried out through vacuum‐assisted headspace solid‐phase microextraction combined with GC‐MS. As a result, a total of 72 volatile compounds were detected and identified during this process, including aldehydes (27), alcohols (14), ketones (10), furans (6), aromatic compounds (9), acids, and esters (6). And the forming temperature of each volatile was determined. Results show most of volatile aldehydes and alcohols were formed at 120°C leading to release off‐flavor largely, which was considered as a critical temperature point for the formation of soybean oil flavor during the whole heating process. Meanwhile, ketones and furans were formed at 150°C, and acids were detected at 180°C. The content of most volatile compounds increased significantly with the temperature raised. Simultaneously, results of principal component analysis demonstrate that flavor characteristics of soybean oil have a big difference between higher and lower temperature in the heating process.
The quality, flavor, and functional attributes of fermented foods are intrinsically shaped by the composition and metabolic dynamics of their microbial communities. This systematic review explores the structural organization, successional patterns, and mechanistic roles of these communities in influencing food quality, with a specific focus on core functional groups—including lactic acid bacteria (LAB), yeasts, and molds—and their interplay through key metabolic pathways. By integrating multi-omics approaches, such as metagenomics and metabolomics, we elucidate the underlying relationships between microbial activity and the formation of volatile flavor compounds, nutritional metabolites, and bioactive substances. These insights offer a scientific basis for the targeted regulation and functional enhancement of fermented food products.
30 January 2022 in Journal of Food Processing and Preservation
Volatile profiling was carried out during heating through vacuum-assisted headspace solid-phase microextraction combined with gas chromatography-mass spectrometry to better understand the flavor forming mechanism of flour products. Ninety-two volatile compounds were detected and identified, including aldehydes (25), ketones (15), alcohols (9), nitrogen- and sulfur-containing compounds (6), benzene derivatives (15), furans (10), and acids and esters (12). The formation temperature of each volatile was also determined. Results showed that temperature played an important role in the formation and content of volatile compounds. In the low-temperature range (60 °C–100 °C), the flavor composition of flour was mainly composed of C6–C10 volatile aldehydes and alcohols. At temperatures exceeding 100 °C, especially at 120 °C, many long carbon chain aldehydes and alcohols, furans, acids, esters, nitrogen- and sulfur-containing compounds were formed. The formation rate of most identified volatile compounds increased during heating, especially from 90 °C to 130 °C.