内容: This study compared the aroma-active compounds in 14 brands of commercially available infant formula and investigated their changes during ambient storage after opening for 2 months. A total of 29 major aroma-active compounds were detected in infant formula. From the principal component analysis and heatmap analysis, a total of 14 brands of infant formula were classified into 3 groups. The second group contained JLB-Y, AY, and FH-F, of which 2-furanmethanol and (E,E)-3,5-octadien-2-one were the main compounds. The third group contained YL and JLB-L, with the characteristic flavor compounds in this group being mainly hexanal, heptanal, etc. Aldehydes, as the main volatile substances, account for more than half of the total volatiles. Nearly half of the aldehydes showed more significant changes after storage, e.g., hexanal, octanal, (E)-2-octenal, and 3-methylbutyraldehyde. The YL and YP-Q produced more saturated aldehydes after storage, being the concentration of hexanal in YL-2m and YP-Q-2m being 2 138.5 and 2 004.1 μg/kg, respectively. The concentrations of heptanal, octanal, and nonanal also increased relatively significantly, which may lead to a distinct rancid flavor in YL and YP-Q. Besides, among the ketones, (E,E)-3,5-octadien-2-one showed the greatest change after storage, especially in JLB-L. According to sensory evaluation experiments, the milky flavor of infant formulas decreased and fatty, rancid, fishy, and grassy flavors were found to have increased to different extents after storage. The current information gap on the concentration and evolution of volatile compounds in commercially available infant formula is filled by this study.

内容: Cordyceps militaris (CM) is widely distributed in humid temperate and tropical forests. Commercially available CM is mainly dried fruiting bodies and their further processed products. In the Chinese market, these products are mainly stored at room temperature without vacuum sealing after air drying. In this study, ultra-high performance liquid chromatography-high-resolution mass spectrometry, gas chromatography-mass spectrometry, and microbial community abundance analysis were applied to analyze the changes of major metabolites and microbial communities in CM dried products and explore the changes in quality during storage at room temperature. A total of 856 non-volatile and 431 volatile substances were detected, of which 195 non-volatile and 85 volatile substances showed significant differences. By analyzing the microbial community relative abundance, the highest relative abundance was observed in the second month, which was then followed by a decline. These results demonstrated that the quality, odor, and nutrient content of CM changed considerably after storage from one to two months. These findings can provide new insights for exploring the optimal consumption time for the best flavor and health function of CM dried products in the future.

内容: The nutritional composition of pear juice, including its flavor profile and bioactive compounds, plays a pivotal role in determining its quality and is significantly influenced by the pear cultivar. This study assessed key flavor compounds, including sugars, organic acids, and volatiles, as well as antioxidant properties (mainly consisting of phenolics, 1,1-diphenyl-2-picrylhydrazyl radical, and hydroxyl radical scavenging activity) and sensory attributes based on electronic tongue and nose technologies, of pear juices across 20 cultivars from four pear species. The results demonstrated a consistent relationship between flavor compounds and sensory attributes. The total sugar content was positively associated with sweetness perception, with Pyrus bretschneideri, Pyrus pyrifolia, and Pyrus sinkiangensis exhibiting higher sugar levels than Pyrus ussuriensis. Similarly, total organic acid content corresponded to sourness perception, following the trend: P. ussuriensis > P. bretschneideri > P. pyrifolia and P. sinkiangensis. Notably, P. ussuriensis juices displayed higher levels of total volatile compounds, especially for esters, as confirmed by electronic nose analysis identifying a distinct volatile profile for this species. Additionally, principal component analysis highlighted that P. ussuriensis juices were characterized by higher levels of total acids, citric acid, malic acid, esters, and antioxidant properties, along with reduced total sugars, glucose, and fructose levels. Partial least squares-discriminant analysis further screened ten differential variables contributing to group differentiation. These results indicated P. ussuriensis juices possessed distinctive characteristics of higher sourness, lower sweetness, rich aroma, and potential health benefits, which will provide foundational information to support the development of the pear juice industry in China.

内容: Radish is a root vegetable with significant nutritional and economic value. However, there is limited information on the flavor and taste profiles of different radish varieties. In this study, headspace gas chromatography-ion mobility spectrometry was used to investigate the characteristic volatile compounds in Weixian green radish, establishing its volatile compound fingerprint. Further, its volatile compound composition was compared with those of other radish varieties. A total of 46 compounds were identified in the Weixian green radish, including 19 aldehydes, six alcohols, five esters, six ketones, three furans, three pyrazines, and four other compounds. Among different radish varieties, the Weixian radish contained the largest number of volatile compounds, followed by hybrid and green-root radish samples. Flavor differences among the different radish varieties were mainly affected by the type and content of esters, aldehydes, and ketones, among which 1-nonanal, propanal, 1-penten-3-one, and isobutyric acid methyl ester were the key flavor contributors. This study not only reveals the differences in the flavor compounds between different radish varieties but also provides a scientific basis for the geographical protection of varieties and market positioning of radishes in Weixian County.

内容: Traditional noni fruit teas (NFTs) are typically sun-dried, which poses limitations for industrial production. While our previous studies showed that drying methods influence noni’s bioactive components, their effects on NFTs flavor and infusion characteristics are still unknown. This study investigated the flavor profiles and taste attributes of NFTs from four drying methods: hot air, vacuum freeze, microwave, and far infrared, while exploring active component release patterns and antioxidant activities during infusion. The results showed that the overall flavor quality of NFTs varied by the four drying methods, with vacuum freeze drying showing superior effects due to higher ester levels, lower octanoic and hexanoic acid concentrations, improved antioxidant activity, and balanced sourness and bitterness. Four key phenolic compounds were identified in NFTs during infusion, with kaempferol-3-O-rutinoside showing a strong affinity for the astringent receptor via molecular docking. This study presented a theoretical framework for enhancing industrial production and improving the quality of NFTs.

内容: Durian (Durio zibethinus Murr.), a prized tropical fruit native to Southeast Asia, is known for its unique texture and sweet-bitter aroma. To understand the primary and secondary metabolites influencing durian’s texture and aroma, an integrative approach combining electronic nose and tongue analyses, transcriptomics, and metabolomics was first applied to three popular durian varieties: Musang King (MK), Monthong (MT), and Kan Yau (KY). The study identified 82 non-volatile and 95 volatile differentially expressed metabolites, with MK containing higher levels of terpenoids and sulfur compounds, while MT exhibited elevated esters and lipid-derived volatiles, contributing to its distinctive sweetness and aroma intensity. In contrast, KY was enriched in phenolic acids and amino acid derivatives, which may influence its bitterness and umami taste. Transcriptomic analysis revealed 12 927 differentially expressed genes, with key metabolic pathways including carbon metabolism, amino acid biosynthesis, and lipid metabolism playing significant roles in distinguishing these varieties. Furthermore, network pharmacology analysis pinpointed 45 key non-volatile metabolites with potential health benefits, including flavonoids, lipids, and alkaloids, which were linked to anti-inflammatory, cardiovascular-protective, and neuroprotective properties. Notably, MK and KY contained bioactive compounds with potential anticancer effects, while MT was associated with metabolites beneficial for metabolic regulation. This study enhances our understanding of the genetic and metabolic basis underlying durian’s texture, aroma, and functional properties, providing a foundation for future breeding and functional food development.