Tea (Camellia sinensis) has grown for over 300 years and is recognized worldwide as among other well-renowned crops. The quality of black tea depends on plucking (method, standard, season, and intervals), withering and rolling (time and temperature), fermentation (time, temperature, and RH), drying (temperature and method), and storage conditions, which have a high influence on the final quality of black tea. At the rolling stage, the oxidation process is initiated and ends at the early drying stage until the enzymes that transform tea polyphenols into thearubigins (TRs) and theaflavins (TFs) are denatured by heat. By increasing fermentation time, TRs increased, and TF decreased. Each is liable for black tea’s brightness, taste, and color. The amino acids and essential oils also grant a distinctive taste and aroma to black tea. Throughout withering, rolling, and fermentation, increases were found in essential oil content, but during drying, a decrease was observed. However, the Maillard reaction, which occurs when amino acids react with sugar during drying, reimburses for this decrease and enhances the flavor and color of black tea. As compared to normal conditions, accelerated storage showed a slight decrease in the total color, TF, and TRs. It is concluded that including plucking, each processing step (adopted technique) and storage system has a remarkable impact on black tea’s final quality. To maintain the quality, an advanced mechanism is needed to optimize such factors to produce high-quality black tea, and an objective setting technique should be devised to attain the desirable quality characteristics.

Peaches are among the most well-known fruits in the world due to their appealing taste and high nutritional value. Peach fruit, on the other hand, has a variety of postharvest quality issues like chilling injury symptoms, internal breakdown, weight loss, decay, shriveling, and over-ripeness, which makes a challenging environment for industries and researchers to develop sophisticated strategies for fruit quality preservation and extending shelf life. All over the world, consumers prefer excellent-quality, high-nutritional-value, and long-lasting fresh fruits that are free of chemicals. An eco-friendly solution to this issue is the coating and filming of fresh produce with natural edible materials. The edible coating utilization eliminates the adulteration risk, presents fruit hygienically, and improves aesthetics. Coatings are used in a way that combines food chemistry and preservation technology. This review, therefore, examines a variety of natural coatings (proteins, lipids, polysaccharides, and composite) and their effects on the quality aspects of fresh peach fruit, as well as their advantages and mode of action. From this useful information, the processors could benefit in choosing the suitable edible coating material for a variety of fresh peach fruits and their application on a commercial scale. In addition, prospects of the application of natural coatings on peach fruit and gaps observed in the literature are identified.

Post-fermented Pu-erh tea (PFPT) is a microbial fermented tea characterized by unique sensory attributes and multiple health benefits. Aspergillus niger is the dominant fungus involved in the fermentation process and plays a significant role in imparting the distinct characteristics of PFPT. To investigate the role of Aspergillus niger in the fermentation of Pu-erh tea, this study inoculated unsterilized sun-dried green tea with Aspergillus niger isolated from Pu-erh tea to enhance the fermentation process. Metabolites and microbial communities in sun-dried green tea (CK), fortified fermented tea (TF), and naturally fermented tea (NF) were analyzed using non-targeted metabolomics, 16S rDNA, and internal transcribed spacer sequencing. Non-targeted metabolomics revealed that Aspergillus niger significantly altered the metabolite profile of the tea samples, identifying a total of 200 different metabolites, with 95 showing significant increases and 105 significant decreases, predominantly enriched in metabolic pathways associated with amino acid biosynthesis and degradation. High-throughput sequencing revealed that although the relative abundance of the fungal community remained largely unchanged, the inoculation of Aspergillus niger significantly increased the abundance of Bacillales and Pseudomonas within the bacterial community, thereby influencing the dynamic balance of the microbial ecosystem. Collectively, the inoculation of Aspergillus niger altered the composition of the microbial community and metabolic activities, resulting in changes to the content of amino acid-dominated metabolites, thereby enhancing the flavor profile and overall quality of Pu-erh tea. These findings provide important insights for optimizing the production processes of Pu-erh tea and the application of microorganisms in other fermented foods.

Gastrodia elata Bl. (GE), a representative medicine–food homology material, requires appropriate processing prior to food application to meet established medicinal quality standards. However, the effects of different traditional processing methods on its quality attributes remain insufficiently elucidated. In this study, three representative processing methods, steaming, moistening, and bran-frying, were systematically compared to evaluate their impact on the structural, compositional, and flavor characteristics of GE. The results demonstrated that processing markedly altered both the physical structure and chemical composition of GE. Moistening caused minimal disruption to the native tissue architecture and largely preserved the free-water distribution pattern. Notably, gastrodin and p-hydroxybenzyl alcohol contents reached 0.38% and 4.16%, respectively, the highest among all treatments, while the overall flavor profile remained closest to that of fresh GE. In contrast, bran-frying induced pronounced dehydration and structural densification, with volatile compounds and differential metabolites accounting for 72.83% and 41.01%, respectively. This treatment also exhibited elevated levels of total phenolics, flavonoids, and protein. Steaming, by comparison, promoted starch gelatinization and water redistribution, shifting the flavor profile from a delicate herbal note toward enhanced umami, floral, and mildly roasted characteristics. Overall, these findings reveal that processing-induced structural remodeling and changes in water state play critical roles in regulating the quality attributes of GE. By integrating structural characterization, water-state analysis, and multi-omics data, this study provides a systematic understanding of the formation of GE quality attributes under different processing methods, offering a theoretical basis for quality control and process optimization.

Biodegradable polysaccharide-protein films are promising alternatives to petroleum-based packaging but often lack adequate structural stability and functionality. Although ultrasound (US), ultraviolet (UV), and microwave (MW) treatments have been individually applied to improve biopolymer films, a systematic comparison on the same film system remains unreported. Here, cactus polysaccharide (CP) was extracted fromOpuntiaspp. with high purity (91.69% polysaccharides, 117.15 μg/g protein, 1.03 mg/g phenolics). CP-gelatin films were fabricated and treated with US (200 W, 20 kHz, 30 min), UV (254 nm, 30 W, 30 min), or MW (300 W, 2450 MHz, intermittent heating). Effects of these physical fields technologies on the structural, physicochemical, mechanical, and functional properties of the films were systematically evaluated. Compared with UV and MW treatments, US treatment resulted in significantly lower moisture content (6.38% vs. 7.09% and 6.78%), water solubility (65.34% vs. 71.51% and 68.22%), swelling index (99.0% vs. 117.7% and 108.5%), and water vapour permeability (1.81 × 10^-7 vs. 2.44 × 10^-7 and 2.25 × 10^-7 g·m^-2·Pa^-1·s^-1), along with the highest tensile strength (20.53 vs. 16.91 and 14.38 MPa), antioxidant activity (ABTS: 93.80% vs. 91.93% and 92.37%; DPPH: 82.48% vs. 78.29% and 81.88%), and UV-shielding performance (UV-A: 85.07% vs. 71.72% and 75.40%; UV-B: 96.99% vs. 91.37% and 93.47%).UV increased visible-light transparency but showed the lowest UV-blocking efficiency, while MW induced localized crystallization and the highest surface hydrophobicity (WCA: 87.56° vs. 74.52° for US and 76.95° for UV). All treatments slowed soil biodegradation versus control. Overall, US provided the most balanced enhancement of structural integrity, barrier performance, antioxidant activity, and UV protection, highlighting its potential for sustainable active packaging applications.