Instant powder, with its high formulation flexibility, ease of quantification, long shelf life, and convenient storage and transportation, holds a significant position in the modern food industry and has experienced rapid development. However, most powder products not optimized for instant use often encounter issues such as surface floating and clumping during rehydration. Some products remain unevenly distributed even after stirring or extending the settling time, severely impacting consumer experience. This paper systematically reviews the key factors influencing the rehydration performance of instant powders, including chemical composition, particle microstructure, and processing techniques. It also delves into corresponding improvement strategies, such as particle structure design, particle modification, and the optimization of rehydration methods. This paper aims to provide theoretical references and practical guidance for technological innovation and product development in the field of instant powders.

Polysaccharides are natural macromolecules with significant functional properties, but the application of certain natural polysaccharides is hindered by their large molecular weight, poor solubility, and limited functionality. In recent years, microbial fermentation has emerged as a sustainable, low-energy-consuming and low-pollution green biotechnology strategy, which degrades and modifies polysaccharides by generating carbohydrate-active enzymes, thereby obtaining new types of polysaccharides with lower molecular weights and stronger functions. Meanwhile, fermented polysaccharides are utilized as prebiotics by intestinal microorganisms. By regulating microbial communities and their metabolites (such as short-chain fatty acids and bile acids), fermented polysaccharides have shown potential value in maintaining metabolic homeostasis and intervening in related diseases. Based on the results of the latest research, this paper summarizes the sources, optimization of fermentation conditions, structural characteristics of fermented food–polysaccharides, with the aim of providing new insights into the utilization of polysaccharides. Meanwhile, focuses on discussing the effects of fermented polysaccharides on the gut microbiota and the mechanisms by which they intervene in disease through regulating the microbiota and its metabolites, which offered new insights and directions for the therapeutic application of fermented food—polysaccharides.

Background: Curcumin (Cur) and tryptophan (Trp) both show promise for treating ulcerative colitis (UC) alone, but their combination has not been explored. This study investigated the therapeutic advantage of the combination (Cur–Trp) for DSS-induced ulcerative colitis in mice. Methods: We established a mouse model of ulcerative colitis induced by dextran sulfate sodium (DSS). The mice were treated with Cur, Trp, or Cur–Trp, and to evaluate the therapeutic effects, we assessed clinical signs such as body weight, disease activity index (DAI), and colon length. We also examined intestinal barrier function through indicators including histopathological changes, inflammatory factors, oxidative stress levels, mucin secretion, and tight junction protein expression. Additionally, we analyzed the composition of gut microbiota and the content of its metabolites like short-chain fatty acids (SCFAs). Results: The Cur–Trp group produced the most significant improvement, exceeding that of Cur or Trp group. This was evidenced by a significant recovery of this sign, including slower weight loss, reduced colon shortening, and de-creased disease activity index. Compared with the model group, the weight loss of mice in the Cur–Trp group was reduced from 17.15% to 9.73%, which was better than that in the cur group (11.33%) and the Trp group (11.59%). The DAI decreased from the model group (3.6) to the Cur–Trp group (2.4), while the DAI in the Cur group and the Trp group only decreased to 2.9 and 2.8, respectively. The colon length in the Cur–Trp group (6.52 cm) was larger than that in the cur group (6.31 cm), the Trp group (6.23 cm) and the model group (5.5 cm). The Cur–Trp intervention effectively restored intestinal barrier function, as shown by reducing colon tissue dam-age, modulating inflammatory factors, restoring oxidative balance, increasing mucin secretion, and upregulating tight junction protein expression. Further studies showed that the combination uniquely modulated the gut microbiome, increased the Firmicutes/Bacteroidetes (F/B) ratio, decreased the genus of pro-inflammatory bacteria, and in-creased beneficial bacteria, while increasing SCFA levels to alleviate DSS-induced ulcerative colitis. Conclusions: Cur–Trp has shown great potential in alleviating colitis and promoting intestinal barrier function, suggesting that the combination of Cur and Trp has the potential to be developed as a therapeutic functional food or dietary supplement for UC. However, more studies are needed to validate this finding. Future research should focus on elucidating the precise molecular mechanisms, optimizing dosage and clinical trials in chronic models and humans to provide more targeted treatment options.

Objective: Pine needles are rich in many nutrients and exhibit antibacterial and antioxidant biological activities; however, the effects of different production methods of pine needle additives on the growth performance and intestinal flora of broiler chickens are not known.Methods: Normal diets were supplemented with pine needle fermentation juice (PNF), pine needle soaking juice (PNS), or pine needle powder (PNP), and the associated effects on growth performance, relative organ weights, intestinal development, intestinal histological morphology, intestinal flora, meat quality, and serum indicators in broiler chickens were observed.Results: The results showed that PNF, PNS, and PNP all significantly improved feed utilisation and promoted the growth and development of broilers. All three additives also significantly improved the structure of the intestinal flora, specifically increasing the diversity of bacteria; increasing the abundance of beneficial bacteria, such as Faecalibacterium, Rikenella, and Blautia; and decreasing the abundance of harmful bacteria, such as Staphylococcus. The antioxidant properties of pine needles were also found to intensify lipid metabolic reactions in the blood, thus leading to lower triglycerides and total cholesterol. Meanwhile, high doses of PNF reduced jejunum and ileum weights and also increased meat yellowness. Lastly, none of PNF, PNS, or PNP had an effect on relative organ weights or intestinal histological morphology.Conclusion: The addition of pine needles to the diet of broiler chickens can effectively promote their growth performance as well as improve their intestinal flora and serum status without side effects; in particular, the dose of 0.2% of either PNF and PNS is expected to have the capacity to replace growth-promoting antibiotics as diet additives.

Exopolysaccharides are important metabolites of Monascus with healthy activities. However, the low production level limits their applications. Hence, the aim of this work was to increase the yield of exopolysaccharides (EPS) and optimize liquid fermentation by adding flavonoids. The EPS yield was optimized via both medium composition and culture conditions. The optional fermentation conditions achieved for EPS production of 7.018 g/L were 50 g/L sucrose, 3.5 g/L yeast extract, 1.0 g/L MgSO₄·7H₂O, 0.9 g/L KH₂PO₄, 1.8 g/L K₂HPO₄·3H₂O, 1 g/L quercetin, and 2 mL/L Tween-80, with pH 5.5, inoculum size 9%, seed age 52 h, shaking speed 180 rpm, and fermentation culture 100 h, respectively. Furthermore, the addition of quercetin increased EPS production by 11.66%. The results also showed little citrinin residue in the EPS. The exopolysaccharides’ composition and antioxidant capacity of quercetin-modified exopolysaccharides were then preliminarily investigated. The addition of quercetin changed the composition of the exopolysaccharides and the molecular weight (Mw). In addition, the antioxidant activity of Monascus exopolysaccharides was monitored using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS⁺), and -OH. Monascus exopolysaccharides have good scavenging ability of DPPH and -OH. Furthermore, quercetin increased the scavenging ABTS+ ability. Overall, these findings provide a potential rationale for the application of quercetin in improving the EPS yield.