Fruit vinegar is a beverage derived from fruits or fruit processing by-products through microbial fermentation. This vinegar possesses a distinctive flavor profile and contains bioactive compounds. It is typically produced using liquid fermentation technology. As consumer demand for the flavor quality of fruit vinegar has increased, precise control over flavor compounds has become crucial for enhancing the quality of fermentation products. Vinegar contains numerous characteristic flavor compounds, including esters, aldehydes, alcohols, and organic acids. These unique flavors primarily result from the accumulation of flavor compounds generated by different raw materials and microorganisms during fermentation. Specifically, yeast and acetobacter promote the formation of distinct fruit vinegar flavors by facilitating the breakdown of carbohydrates, amino acids, and proteins in fruits, as well as the redox and esterification reactions involving alcohols. This paper reviews the metabolic pathways of yeast and acetic acid bacteria during fruit vinegar fermentation and discusses key volatile compounds that influence the flavor of fruit vinegar and their potential relationships, providing theoretical support for regulating flavor quality.
With improving economic conditions, consumer demand for fresh-cut produce is rising. The development of the fresh-cut industry has been hindered by pathogenic contamination and quality deterioration. Scientific communities have developed novel preservation technologies for fresh-cut produce. As an innovative non-thermal processing method, cold plasma effectively preserves the nutritional value and inactivates pathogens in fresh-cut produce. This review delineates the principles of cold-plasma generation and concludes with the primary factors influencing its efficacy. These factors include the specifications and parameters of the equipment utilized, the properties of the conductive gas utilized, the method of treatment, and the intrinsic properties of a sample subjected to treatment. Furthermore, this review delineates various scenarios for cold-plasma applications. This review focuses on its effects on enzymatic activities (including peroxidase, polyphenol oxidase, and pectin methylesterase), pathogenic microorganisms, and nutritional value. This review concludes with the potential application of cold-plasma technology in the processing of fresh-cut products. This study proposes advancing plasma technology in fresh-cut produce processing by (1) optimizing cold-plasma parameters for diverse fruit and vegetable varieties and (2) scaling up to facilitate industrial application.
Tomato (Solanum lycopersicum L.) is a nutritious fruit and vegetable. Fermentation can be used to enhance their nutritional value. In this study, the tomato juice was co-fermented with multistrains, optimized by uniform experimental design and response surface methodology. Superoxide dismutase activity reached 496.67 U/g and lycopene content reached 77.12μg/g when P. pentosaceus (53.79%), L. casei (13.17%), L. plantarum (19.87%), L. fermentum (13.17%). To gain insight into the dynamics of metabolites during the tomato fermentation juice process multivariate statistical analysis was performed using the UHPLC-QE-MS/MS method. The main metabolites are peptides, amino acids carbohydrates, organic acids, and phospholipids. Carbohydrates were fully retained at the end of fermentation.The content of galactitol increased from the initial 5.389 to 6.607 while the content of cytarabine decreased by 29% and uridine by 44%. Meanwhile, phospholipids (PS, PE, PC, PG, PI) were all retained by more than 70%. Terpenoids (16-deacetylgairin, (+)-Royleanone, artemisinin) were increased to varying degrees, which gives them good nutritional value and biological activity. Organic acids (malic and citric) were reduced and lactic acid content was increased, changing its original flavor and making it more palatable to the general population. The research results have demonstrated the benefits of lactic acid bacteria fermentation on tomato juice, providing a theoretical basis and reference for the fermentation metabolism process of tomato juice.
The substantial quantity of discarded tomato pomace (TP) results in the waste of valuable resources. This study utilizes these tomato by-products by mixing them with water in a specific proportion and fermenting the mixture in two stages: first with yeast, and then with lactic acid bacteria. The most suitable microbial strains for TP fermentation were identified by evaluating parameters such as peptide content, degree of hydrolysis, and gel electrophoresis analysis. Subsequently, tomato pomace peptides (TPPs) were separated into peptides of different molecular weights using ultrafiltration. The IC50 values, ACE inhibitory activities, and in vitro stability of these peptides were compared, and their secondary structures and microstructures were characterized. The results indicated that the soluble protein concentration increased from 26.25 mg/g to 39.03 mg/g after 32 h of fermentation with strain RV171. After an additional 32 h of fermentation with Bifidobacterium thermophilum, the peptide content reached 49.18 ± 0.43%. SDS-PAGE gel electrophoresis showed that the TPP molecular weights were predominantly below 10 kDa. The IC50 results demonstrated that fractions with smaller molecular weights exhibited greater ACE inhibitory activities. Structural analysis confirmed that the TP hydrolysate was indeed a peptide.
Chronic alcohol consumption is a major contributor to gastric injury, yet current therapeutic strategies predominantly rely on chemical agents with limited efficacy and potential side effects. Natural products, with their multi-target biocompatibility and safety advantages, offer promising alternatives for gastric protection. We examined the phenolic compounds of Elaeagnus angustifolia honey (EAH) and investigated its prophylactic potential against ethanol-induced chronic gastric injury in mice. HPLC-DAD-Q-TOF-MS analysis showed that 21 phenolic compounds were tentatively and qualitatively identified in EAH, as well as 14 phenolic compounds. Moreover, gastric ulcer indices, histopathological morphology, oxidative stress markers (MDA, GSH, SOD), inflammatory mediators (NO, PGE2), and cytokine gene expression (TNF-α, IL-6, IL-1β, iNOS) were evaluated via enzyme-linked immunosorbent assay (ELISA) and quantitative real-time PCR. Western blot was employed to assess COX-2 protein expression, while 16S rRNA sequencing analyzed gut microbiota composition. The results demonstrated that EAH could play a role in gastric injury caused by long-term alcoholism by protecting gastric tissue structure, interfering with oxidative stress and inflammatory response, and remodeling the intestinal microbial community.
This study investigated the impact of three different charged hydrocolloids, anionic polysaccharide (soluble soybean polysaccharide, SSPS), neutral polysaccharide (pullulan polysaccharide, PUL), and cationic polysaccharide (chitosan, CS), and their complexation on the stabilization efficiency of fermented tomato juice (FTJ). The effect of hydrocolloids on FTJ under different treatment conditions were comprehensively evaluated by determining the particle size distribution, zeta potential, rheological properties, Fourier transform infrared spectroscopy, surface tension, and LUMiSizer. The combined conditions suggest that PUL exhibits better storage stability than SSPS and CS when used individually. Compared with the use of the stabilizers, the combination of hydrocolloids had a greater impact on the storage stability of the FTJ, and the storage stability of the FTJ increased when 0.15% SSPS + 0.03% PUL + 0.15% CS was added. This study lays the groundwork for the development of stable fruit juice beverages.