Ultrasound-assisted enzymatic treatment was used to treat Newhall navel orange peel and residue, and then the structural, physicochemical and functional properties of extracted soluble dietary fibers (SDF) and insoluble dietary fibers (IDF) were investigated. The structural properties were determined using scanning electron microscopy, X-ray diffraction, FT-IR and monosaccharide composition. Among these dietary fibers, residue-SDF showed a more complex structure, while peel-IDF exhibited a looser structure. Four samples showed representative infrared spectral features of polysaccharides, typical cellulose crystalline structure and diverse monosaccharide composition. Furthermore, residue-IDF exhibited higher oil-holding capacity (2.08 g/g), water-holding capacity (13.43 g/g) and nitrite ion adsorption capacity (NIAC) than other three samples, and residue-SDF showed the highest swelling capacity (23.33 mL/g), cation exchange capacity (0.89 mmol/g) and cholesterol adsorption capacity (CAC) among these dietary fibers. In summary, this study suggests that the residue-SDF and residue-IDF could be used as the ideal dietary fibers for application in the functional food industry.

This paper compared the effects of air and nitrogen on the freezing characteristics, color, and cell structures of chestnut kernels at different rates of heat transfer and adopted liquid nitrogen spray quick-freezing (NF_{−40 °C/−60 °C/−80 °C/−100 °C}) and still air freezing (AF_{−20 °C/−40 °C}) as the freezing methods. The ratio of heat transfer coefficients in N₂ groups was two times as high as those in air groups, and NF_{−100 °C} and NF_{−80 °C} showed better freezing characteristics, good protection for cytoskeletons, and the color was similar to those of the fresh group. Taking both Multivariate Analysis of Variance (Principal Components Analysis and Cluster Analysis) and economic factors, NF_{−80 °C} can be used as a suitable method for chestnut kernel freezing. When the ambient freezing temperature was lower than T_g, both NF and AF treatment groups presented poor quality. The rate and medium of heat transfer jointly influenced the freezing characteristics and quality. The former had a greater effect than the latter, however.

This study employed ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) combined with multivariate analysis to investigate tissue-specific metabolic profiles in the peel, pulp, and seeds of black wax gourd (Benincasa hispida). A total of 1020 metabolites were identified, including 520 primary metabolites (e.g., amino acids, lipids, and organic acids) and 500 secondary metabolites (e.g., phenolic acids, flavonoids, and alkaloids). Significant metabolic divergence was observed across tissues: 658, 674, and 433 differential metabolites were identified between the peel and the pulp, the peel and the seeds, and the pulp and the seeds, respectively. Unique metabolites such as methyl 5-glucosyloxy-2-hydroxybenzoate and 3,5-di-O-caffeoylquinic acid were exclusive to the peel, while 4-O-(6′-O-glucosyl-imino)-4-hydroxybenzyl alcohol and fertaric acid were specific to the seeds. KEGG pathway enrichment revealed distinct metabolic priorities: flavonoids and phenolic acids dominated in the peel, amino acids and phenylpropanoids in the pulp, and nucleotides and lipids in the seeds. The peel exhibited the highest secondary metabolite abundance (14.27%), whereas the seeds accumulated the most primary metabolites (26.62%), including essential amino acids like L-tryptophan and functional lipids such as linoleic acid. These findings underscore the nutritional and bioactive potential of underutilized by-products (peel and seeds), providing a biochemical foundation for valorizing wax gourd tissues in the food, pharmaceutical, and agricultural industries.

This study investigated the impact of glycerol monooleate (MO) at varying levels (0.3%, 0.6%, 0.9%, and 1.2%) on the quality and baking properties of frozen dough. Low-field NMR and MRI were used to analyze the moisture distribution, water migration, and structural changes during frozen storage. The results indicated that MO reduced the content of free water, leading to a decrease in the spin–spin relaxation time of free water (T23). At the same time, the increase in the content of bound water resulted in an increase in the spin–spin relaxation time of bound water (T21). Rheological and SEM analyses revealed that MO preserved the dough’s microstructure and improved its rheological properties, reducing mechanical damage and inhibiting free water crystallization. This study found that by 8 weeks of frozen storage, the frozen dough containing 0.6% MO exhibited the best fermentation performance, with a larger fermentation volume and specific volume, and lower bread hardness, measuring 80 mL, 3.48 mL/g, and 1.10 N, respectively. These findings highlight MO’s potential in terms of enhancing frozen dough quality by maintaining the moisture balance and structural integrity during storage, offering a practical approach to improving bakery product quality.