Cyclodextrins are tapered cyclic oligosaccharides, which are used to encapsulate a wide range of compounds, such as phytochemicals and drugs. They can be divided roughly into native, modified, and large-ring cyclodextrins: native- and large-ring cyclodextrins are prepared from starch by cyclodextrin glycosyltransferase and are further chemically modified, improving their chemical properties, such as water-solubility. Cyclodextrins have many possible applications in food processing due to their inclusion complexation characteristics. Cyclodextrins can be used to improve the color properties of food by protecting natural pigments from degradation during storage or by inhibiting enzymatic browning. In addition, encapsulation of bitter compounds inhibits their interactions with taste receptors in the oral cavity, decreasing undesirable taste properties. Finally, encapsulation of hydrophobic compounds improves their dispersion in the aqueous matrix, increasing the bioavailability and antioxidative activity of the target compounds. Studies have shown that successful use of the cyclodextrin requires good planning and understanding of the chemical composition of the food product.

The peel of pitaya fruit is a promising source of pectin, and non- or low-methylesterified pectin has multiple bioactivities and application scenarios. In this study, non-methylated pectin was prepared from pitaya peel and the structure was characterized. Single factor experiment and response surface methodology were conducted to optimize the procedure of ultrasonic-assisted extraction for pectin. Under the optimal conditions (solid-liquid ratio of 1:40 g·mL−1, extraction temperature at 56 °C, extraction time of 25 min and ultrasonic power of 200 W), the pectin yield was up to 9.93% ± 0.97%. Degree of methylesterification and FTIR analysis confirmed that the extracted pectin was almost non-methylesterified. The pectin possessed less linear homogalacturonan (HG) but more rhamnogalacturonan (RG) regions according to the molar ratios of monosaccharides. Meanwhile, the molecular weight of the pectin was 33.52 kDa and the crystalline index was only 0.60%. Furthermore, the nanoscale structure observed by atomic force microscopy showed that the pectin was rich in highly branched polymers. Generally, pitaya peel pectin extracted by ultrasonic-assisted extraction showed a wide range of potential use as a non-or low- methylesterified pectic substance to reach the efficient utilization of fruit waste.

Investigating the influences of different sterilization methods on overall juice quality is essential for the production of high-quality juice. The effects of ultra-high temperature instantaneous sterilization (UHT), thermosonication (TS), high hydrostatic pressure sterilization (HHP), and irradiation sterilization (IS) on the physicochemical properties, functional components, and color of Aronia melanocarpa juice (AMJ) were investigated. In addition, anthocyanin target metabolomics were used to explore the influences of different sterilization methods on the AMJ anthocyanin profile. All sterilization treatments effectively ensured the microbial safety of AMJ, and the AMJ viscosity was noticeably declined after sterilization (p < 0.05). Except for HHP, the other treatments aggravated AMJ browning (p < 0.05). Both TS and HHP treatments significantly enhanced or preserved the total polyphenols, flavonoids, and anthocyanins in AMJ and retained the original juice color, whereas UHT and IS treatments were not conducive to maintaining these characteristics. TS treatment significantly increased cyanidin-3-O-galactoside (C-3-O-gal) and cyanidin-3-O-arabinoside (C-3-O-ara) contents in AMJ by 7.98% and 5.90%, while IS resulted in a significant decrease of 15.74% and 10.46% (p < 0.05). C-3-O-gal and C-3-O-ara were the major reasons for the significant upregulation and downregulation of the total monomeric anthocyanins contents (TMAC) in the AMJ after TS and IS treatment, respectively. Malvidin-3-O-glucoside (M-3-O-glu), Cyanidin-3-O-(6-O-malonyl-β-D-glucoside) and Kaempferol-3-O-rutinoside (K-3-O-rut) might be markers of differential metabolites produced by the TS, HHP, and IS treatments, respectively. Correlation analysis indicated that Cyanidin-3-O-xyloside (C-3-O-xyl), C-3-O-ara, and Pelargonidin-3-O-arabinoside (P-3-O-ara) might be the principal contributed to the antioxidant capacity of AMJ. The research results are anticipated to supply technical reference for AMJ processing.

Studying the metabolic patterns underlying the key quality traits during the growth and development of melon is very important for the quality improvement and breeding of melon fruit. In this study, we employed transcriptomics and metabolomics to analyze the primary metabolic changes occurring in melon ('Xizhoumi 25') across five growth and development stages. We identified a total of 666 metabolites and their co-expressed genes, which were categorized into five different metabolic and gene modules. Through the analysis of these modules, the main metabolic pathways during the growth and development of melon were demonstrated from a global perspective. We also discussed the contribution of sucrose accumulation, the TCA cycle, and amino acid metabolism to the quality and flavor of melon. Enzymes related to amino acid metabolism were proposed, including Amine oxidase (AOC), aldehyde dehydrogenase (ALDH), tryptophan synthase (TRPB), etc. These results and data can provide new insights for further study on the metabolic regulation of melon quality and improve fruit quality.

Vibrational spectroscopy is a green, rapid, and affordable analytical tool for analysing the quality, safety, and origin of biological materials in agri-food sectors. Pre-processing spectral data is crucial to removing instrumental interferences and physical artifacts when developing a classification model. However, there has yet to be a consensus on which spectral pre-processing method, settings, and decision parameters to use to optimise pre-processing for different spectroscopy tools. Using an arbitrary criterion poses a risk of applying the wrong type or too severe pre-processing that removes valuable information or affects the model's performance for prediction studies. Matthew's Correlation Coefficient (MCC) - a statistic for parameterising classification performance, accounts for data set imbalance and improved decisions on model selection to express uncertainty on future predictions. Four vibrational spectroscopy instruments [near-infrared (NIR), hyperspectral (HSI), mid-infrared (FTIR), and Raman] were compared using different pre-processing methods to understand the performance using MCC to classify coffee from four countries (Indonesia, Ethiopia, Brazil and Rwanda). Key decision parameters were evaluated for the development of reliable classification models. The best pre-processing for NIR was extended multiplicative scatter correction with mean centering (MNCN), and for HSI, Savitzky-Golay (1st derivative, 15 points) with MNCN. NIR performed the best across all four instruments, with FTIR performing the worst. Raman showed potential for coffee origin classification using the right pre-processing. Pre-processing with weighted least squares, normalisation, and MNCN eliminated the fluorescence effect on Raman spectral data. These findings show the feasibility of using MCC for classification problems.

β-ionone has various biological activities, such as anti-inflammatory, antimicrobial, and anticancer effects. The pathogenesis of ulcerative colitis is correlated with immune dysfunction, intestinal barrier damage, and gut microbiota imbalance. However, whether β-ionone has preventive efficacy against ulcerative colitis is unknown. This study investigated the effect of β-ionone on dextran sulfate sodium-induced ulcerative colitis and the underlying molecular mechanisms involved. The ulcerative colitis mouse model was induced by 1.5% dextran sulfate sodium for 10 d. Meanwhile, 200 mg/kg β-ionone was administrated to the mice. Body weight, colon length, colon tissue pathology, colon tissue inflammatory cytokines, colonic oxidative stress, and barrier function were assessed. The composition and structure of gut microbiota were profiled using 16S rRNA sequencing. The results showed that β-ionone supplementation effectively prevented ulcerative colitis by ameliorating colonic tissue damage, reducing inflammatory phenomena, and protecting the colonic epithelial mucosal barrier. β-ionone also protected mice from dextran sulfate sodium-induced gut microbiota disturbance by modifying the overall structure and function of the gut microbiota community and increasing the relative abundance of beneficial gut microbiota. The Spearman correlation analysis revealed that the changes in abundance of the gut microbiota were correlated with ulcerative colitis-related indicators. Overall, this study demonstrated that β-ionone has a preventive effect on ulcerative colitis in mice, and the underlying mechanism may be associated with the protection of the gut barrier and regulation of the gut microbiota. These results are conducive to promoting clinical trials and product development of β-ionone for the prevention and treatment of ulcerative colitis.

The dissolution patterns of different teas determine the sensory quality and health attributes of the tea infusion. In this study, the chemical profiles of two typical selenium-enriched green teas, Xiazhou Bifeng (Se-BF), Enshi Yulu (Se-YL), and their corresponding regular green teas (BF and YL) were determined. Under the application of selenium fertilizer, the contents of caffeine, polyphenols, and gallic acid decreased, while the contents of theaflavins, theabrownins, and chlorophylls increased. The selenium content in BF and YL is 0.05−0.16 mg/kg and 0.33−0.43 mg/kg respectively, while after the application of exogenous selenium, the selenium content in Se-BF and Se-YL reached 1.28 to 2.17 mg/kg and 0.37−2.23 mg/kg respectively. The dissolution patterns of Se-BF and Se-YL were investigated under different brewing conditions (temperature and duration), and the main components of Se-YL were more easily dissolved out than Se-BF, which might be attributed to the steaming process of Se-YL. Based on the sensory evaluation of tea infusion, 100 °C and 5 min were the optimal brewing conditions. Based on a daily tea consumption model, the increased brewing time reduced the content of dissolved components in tea infusions, along with the decreased in vitro antioxidant and hypoglycemic activities. Collectively, Se-YL demonstrated superior sensory and nutritional attributes compared to Se-BF. This study explored the influence of brewing conditions on the dissolution patterns and in vitro bioactivities of selenium-enriched green teas, providing guidance for scientific tea brewing and consumption.

Designing a wound dressing that offers excellent antibacterial properties while providing dual pH/glucose responsiveness for diabetic wound healing remains a considerable challenge. Herein, a 3D cross-linked native protein hydrogel was constructed through a Schiff base reaction based on -NH2 in paramyosin (PM) and -CHO in oxidized dextran (ODA) under mild conditions. Within the hydrogel, both amikacin and glucose oxidase were encapsulated during gelation. The resulting hydrogel exhibited favorable rheological properties, featuring self-healing, antibacterial activity, tissue adhesiveness, and excellent biocompatibility. Notably, the hydrogel demonstrated excellent pH/glucose dual-responsive properties. In infected wounds, the Schiff base bonds dissociated due to low pH, while in uninfected wounds with high blood glucose levels, the encapsulated glucose oxidase was functional, which also lowered the local pH level and dissociated the Schiff base bonds. Furthermore, the hydrogel quickly achieved pH/glucose dual responsiveness, leading to increased amikacin release to reduce bacterial invasion, alleviate oxidative stress, promote re-epithelialization and collagen deposition, and eventually accelerate diabetic wound healing. Collectively, the constructed hydrogel offers brand-new viewpoints on glucose-responsive biomaterials for diabetic wound therapy.

To swiftly and noninvasively assess the freshness of bighead carp heads within simulated cold chain environments, an excitation-emission matrix fluorescence spectroscopy coupled with a long short-term memory network (EEM-LSTM) model was developed. Through the parallel factor algorithm based on analysis of residuals, diagnosis of core consistency, and split-half evaluation, three key fluorescent components from fish fillets were extracted, with the most significant components linked to tryptophan and NADH, both indicative of fish freshness. The EEM-LSTM model exhibited coherent trends in freshness indicators and demonstrated exceptional predictive capabilities for four freshness indicators simultaneously, achieving R2 values exceeding 0.8840 in simulated cold chain situations. Relative errors in the supermarket direct sales cold chain were less than 10%, surpassing those of the long-distance transport cold chain. Hence, the EEM-LSTM model stands validated for predicting fish freshness in simulated cold chains, holding promise for real-world aquatic product freshness forecasting within cold chain scenarios.