Two polysaccharides from Carthamus tinctorius L. (CTLP-1 and CTLP-2) were purified, and their structures were analyzed by physical and chemical testing. CTLP-1 had a mass of 5900 Da that was composed of arabinose, glucose, and galactose with a mass molar ratio of 6.7:4.2:1. The backbone of CTLP-1 was →1)-α-GalAp-(1→4)-α-Arap-(1→2)-α-Glup-(4→. CTLP-2 had a mass of 8200 Da that was composed of arabinose, glucose, and galactose with a mass molar ratio of 16.76:4.28:1. The backbone of CTLP-2 was →1)-α-Galp-(2,6 →1)-α-Arap-(4,6 →1)-α-Glup-(3→. Both of them exhibited a high reducing power, hydroxyl radical scavenging activity, DPPH radical scavenging activity and ABTS radical scavenging activity, moderate Fe²⁺ chelating activity and superoxide anion scavenging activity, implying that they might be potential antioxidants.

Using Meyerozyma guilliermondii YB4, which was isolated and screened from southern Sichuan pickles in the laboratory, as the experimental group, we investigated the changes in growth, total ester content, and volatile flavor substances of M. guilliermondii YB4 under different NaCl concentrations. The growth of M. guilliermondii YB4 was found to be inhibited by NaCl, and the degree of inhibition increased at higher NaCl concentrations. Additionally, the total ester content of the control group (CK) was significantly lower compared to the other groups (p < 0.05). The application of NaCl also resulted in distinct changes in the volatile profile of YB4, as evidenced by E-nose results. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) were employed to analyze the volatile compounds. A total of 148 and 86 volatiles were detected and identified using GC-MS and GC-IMS, respectively. Differential volatiles among the various NaCl concentrations in YB4 were determined by a variable importance in projection (VIP) analysis in partial least squares-discriminant analysis (PLS-DA). These differentially expressed volatiles were further confirmed by their relative odor activity value (ROAV) and odor description. Ten key contributing volatiles were identified, including ethanol, 1-pentanol, nonanal, octanal, isoamyl acetate, palmitic acid ethyl ester, acrolein, ethyl isobutanoate, prop-1-ene-3,3’-thiobis, and 2-acetylpyrazine. This study provides insights into the specificities and contributions of volatiles in YB4 under different NaCl concentrations. These findings offer valuable information for the development of aroma-producing yeast agents and the subsequent enhancement in the flavor of southern Sichuan pickles.

Salt is a key ingredient that can both enhance the taste and extend the shelf life of fermented vegetables. However, it is important to note that excessive salt levels can have adverse effects on consumer health. This study aimed to investigate the impact of various salt additions (2%, 4%, 6%, 8%, and 10% wt/wt) on the flavor profile of fermented ciba pepper, a traditional Chinese fermented chili sauce, using gas chromatography–ion mobility spectrometry (GC-IMS) in combination with an electronic nose (E-nose). Fermented ciba pepper samples were prepared with different salt additions: 2% (LJA), 4% (LJB), 6% (LJC), 8% (LJD), and 10% (LJE) (wt/wt). The physicochemical and sensory properties of the fermented ciba pepper samples were evaluated. Sensory evaluation indicated that LJC and LJD received higher scores compared to the other groups. The total acid and amino acid nitrogen contents displayed contrasting trends with the salt additions (p < 0.05). The E-nose analysis successfully differentiated the flavor profiles of the ciba pepper samples fermented with varying salt additions. Additionally, the GC-IMS analysis identified a total of 72 volatile compounds, including 14 alcohols, 21 esters, nine aldehydes, four acids, eight ketones, three terpenes, and eight other substances. Notably, the ciba pepper samples with lower salt additions exhibited higher levels of alcohols, aldehydes, and esters. In conclusion, the addition of salt during the fermentation process significantly influenced the formation of flavor compounds in ciba pepper. This study provides valuable insights into ciba pepper fermentation with different salt additions and offers prospects for the development of low-salt fermented ciba pepper products.

Sichuan pepper is known for its unique aroma and tingling, numbing sensation, making it a key ingredient in Sichuan cuisine. This study explored the effect of harvest periods on the quality of Sichuan pepper at five selected harvest periods (LSA (early harvest), LSB, LSC, LSD, and LSE (late harvest)) along the 24 solar terms in the traditional Chinese lunar calendar. Apart from evaluating their physicochemical and volatile profiles, the growth characteristics, polyphenol and flavonoid contents, antioxidant properties, and free amino acid and other nutrient concentrations in these peppers were also analysed. Results showed that the moisture content, weight, and shape of Sichuan peppers improved progressively, peaking at the LSE harvest period. Throughout maturation, the energy content of the Sichuan pepper remained stable. Polyphenols and flavonoids, indicators of antioxidant capacity, increased in later harvest periods. A total of 18 amino acids were detected in Sichuan pepper. Proline was the most abundant amino acid, followed by serine, arginine, and glutamic acid, accounting for 83% of the total amino acids. Based on the taste threshold values of amino acids, a taste activity value (TAV) analysis of the amino acids was conducted. The TAV analysis of arginine and glutamic acid were greater than 1, indicating their significant contribution to the bitterness and umami taste, respectively. Through the principal component analysis of the electronic tongue, it was found that Sichuan pepper picked in late July (LSA stage) had a significant difference from that picked in September (LSD and LSE stages), while the difference in taste characteristics between Sichuan pepper in early September and late September was relatively small. Terpenes were the primary volatile compounds, and the number of compounds increased as the harvest period was delayed. PLS-DA analysis revealed that D-limonene had the highest VIP value, indicating its significant contribution to the overall odour of Sichuan pepper, and thus can serve as an indicator for assessing the maturity of Sichuan pepper. This study offers valuable insights for optimising the harvesting period of Sichuan pepper and serves as a theoretical reference for enhancing the development of the seasoning industry.

This study investigated the effects of key seasonings—Pixian Doubanjiang and Daokou Lajiao—and the oil splashing process on the flavor of Water Boiled Beef. Electronic nose, electronic tongue, gas chromatography–ion mobility spectrometry (GC-IMS), and sensory evaluation, combined with multivariate analyses, were used to characterize flavor attributes and volatile compounds. Results from the electronic nose indicated that Daokou Lajiao had the greatest impact on aroma, whereas the electronic tongue suggested that Pixian Doubanjiang made the strongest contribution to umami. GC-IMS identified 64 volatile compounds, mainly aldehydes, alkenes, and alcohols; ROAV highlighted nine key aroma-active compounds (e.g., butanal and (Z)-ocimene), and OPLS-DA identified 25 compounds (VIP > 1) that contributed significantly to sample differentiation. Sensory evaluation further revealed that omission of Pixian Doubanjiang reduced umami and acceptability, while omission of Daokou Lajiao weakened pungency and numbness, and the absence of oil splashing enhanced aroma.