To address the problem of rapid postharvest softening of persimmon fruit, the effects of treatment with 1.0 μL/L 1-methylcyclopropene (1-MCP), modified atmosphere packaging (MA) and their combination on the softening and related physiological indicators of ‘Huo’ persimmon fruit with and without calyx lobes were investigated during postharvest controlled freezing point ((-0.5 ± 0.3)℃) storage. It turned out that both individual and combined treatments delayed persimmon softening. Calyx lobe retention combined with MA provided the best maintenance of high CO₂ and low O₂ concentration in the storage environment and effectively inhibited β-galactosidase (β-Gal) activity. Calyx lobe removal combined with 1-MCP treatment was the most effective in delaying the decrease in fruit hardness, inhibiting the activity of cellulase (CX) and polygalacturonase (PG), reducing respiration intensity and ethylene production rate, and decreasing the loss of total flavonoids. 1-MCP + MA slowed down the decrease in skin hardness and reduced the loss of VC and total phenols. Furthermore, removing the calyx lobes delayed the emergence of a second ethylene peak. Overall, 1-MCP treatment of persimmon fruit without calyx lobes can delay persimmon softening and preserve persimmon quality well during CF storage.

With the growing prosperity of the wine market, consumers have paid more attention to wine quality. The geographical origin and variety of wine are important factors determining wine quality. Volatile components play an important role in the characterization of a specific geographical origin or variety of wine. Therefore, the analysis of volatile compounds in wine is significant for the identification of the geographical origin and variety of wine. In this article, we summarize the analytical methods used to determine volatile compounds in wine and the current status of research on the identification of the geographical origin and variety of wine based on analysis of volatile compounds, with the aim of promoting in-depth research on the volatile compounds of wine and providing theoretical references for ensuring the quality and authenticity of wine and establishing a more complete wine volatile fingerprint.

To explore the metabolic pathways involved in oligosaccharide synthesis during the fruit development of Lycium barbarum, we investigated the differential expression of oligosaccharide synthesis-related proteins at different developmental stages of L. barbarum (S1—young fruit, S2—green fruit, S3—early yellowing, S4—late yellowing, and S5—full fruiting) using isobaric tags for relative and absolute quantitation (iTRAQ). A total of 1799 differentially expressed proteins were identified, 133 of which were found to be associated with oligosaccharide metabolism by Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Oligosaccharide accumulation in L. barbarum fruits at the first three stages was mainly dependent on photosynthesis. Changes in the biosynthesis and metabolism of oligosaccharide were mainly related to the gene and protein expression of sucrose synthase (SS), sucrose phosphate synthase (SPS) and hexokinase (HK). At stages S4 and S5, oligosaccharide accumulation was achieved through the metabolism of starch and polysaccharide and the enzymes related to changes in the biosynthesis and metabolism of oligosaccharide included raffinose synthase, β-fructofuranosidase and endoglucanase. The gene expression of 10 oligosaccharide biosynthesis-related enzymes as detected by real-time polymerase chain reaction (PCR) was consistent with the proteomics results. This study provides a theoretical basis for further elucidating the mechanism of oligosaccharide biosynthesis and metabolism during the fruit development of L. barbarum.

In this study, the composition of volatile flavor substances during the fermentation of cream was analyzed by solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). A total of 32 volatile substances were identified at five different periods, among which acids were the most abundant. Principal component analysis (PCA) revealed that the composition of volatile compounds differed at different fermentation periods, and samples from different periods could be clearly distinguished. Nine key flavor components, including capric acid, caprylic acid, δ-decalactone, 2-nonanone and 3-hydroxy-2-butanone, were identified by calculating odor activity values (OAVs). Five sensory attributes of the samples were scored by descriptive sensory analysis. The correlations between key flavor substances and sensory attributes were analyzed by partial least squares regression (PLSR) analysis, and it was found that the fermented and creamy flavor had strong correlations with capric acid, capric acid, δ-decalactone, 2-decanone, 2-nonanone and 3-hydroxy-2-butanone. This study is of great significance to regulating the production of fermented cream.