Mengmei Ma

Background: Due to the increasing production and significant nutritional benefits of sweet potato, it is crucial to utilize sweet potato as raw powder for various applications. However, there is still a lack of optimum processing technology for the production of sweet potato raw powder with an emphasis on the quality parameters. The present research aimed to improve the quality of sweet potato raw powder by investigating the impact of color protection combined with various drying techniques on the nutritional, physico‐chemical, and pasting characteristics thereof. Results: Compared with sun drying alone (O1, P1), the combined treatment of 1% ( w/v ) ascorbic acid for color protection and microwave vacuum drying (O6, P6) significantly enhanced the nutritional profile of both orange and purple sweet potato raw powders, which increased the content of protein, total dietary fiber, starch, total polyphenols by 9.06–10.82%, 27.25–30.67%, 11.26–13.96%, and 20.52–32.18%, respectively. Furthermore, the resulting powders exhibited superior quality attributes, including color, water absorption index, water solubility index, swelling capacity, and flowability, which were comparable to those of samples prepared by freeze‐drying. Conclusion: The findings indicated that ascorbic acid treatment combined with microwave vacuum drying was an effective technique for processing sweet potato raw powder, and it could also be developed on a larger production scale. © 2025 Society of Chemical Industry.

The effects of Lacticaseibacillus rhamnosus and Pediococcus pentosaceus on the nutritional–functional composition, structure, in vitro saliva–gastrointestinal digestion, and colonic fermentation behaviors of fermented sweet potato residues (FSPR) were investigated. The FSPR was obtained under the condition of a solid-to-liquid ratio of 1/10, inoculation quantity of 1.5%, mixed bacteria ratio 1:1, fermentation time of 48 h, and fermentation temperature of 37 °C. The FSPR showed higher contents of soluble dietary fiber (15.02 g/100 g), total polyphenols content (95.74 mg/100 g), lactic acid (58.01 mg/g), acetic acid (1.66 mg/g), volatile acids (34.26%), and antioxidant activities. As exhibited by FTIR and SEM, the higher peak intensity at 1741 cm⁻¹ and looser structure were observed in FSPR. Further, the FSPR group at colonic fermentation time of 48 h showed higher content of acetic acid (1366.88 µg/mL), propionic acid (40.98 µg/mL), and butyric acid (22.71 µg/mL), which were the metabolites produced by gut microbiota using dietary fiber. Meanwhile, the abundance of Bifidobacterium and Lacticaseibacillus in the FSPR group was also improved. These results indicated that FSPR potentially developed functional foods that contributed to colonic health.

BACKGROUND: Sweet potato (Ipomoea batatas L.) is the sixth most important food crop in the world, and China is the largest producer. Large amounts of sweet potato residues are generated during starch extraction, leading to environmental pollution and resource waste. However, these residues can be used as a viable source for pectin extraction. As a natural biopolymer with high molecular weight and complex structure, the usefulness of pectin has been limited, and it needs to be modified in order to improve its physicochemical properties, thus expanding its applications in the food industry. Therefore, the reported study was conducted to modify sweet potato pectin (SPP) using high hydrostatic pressure (HHP) and/or pectinase treatment, and to determine the effects of such treatment on structural, physicochemical and emulsifying properties.RESULTS: The results demonstrated that the molecular weight of SPP decreased following HHP and pectinase treatment, which was evidenced using scanning electron microscopy and atomic force microscopy. The degree of esterification was also decreased, confirmed by decreased intensity of the peak at 1739 cm⁻¹ in the Fourier transform infrared spectrum and decreased peaks at 3.6 and 3.8 ppm in the ¹H NMR spectrum. Moreover, the content of monosaccharides and uronic acids increased and emulsifying properties improved after HHP and pectinase treatment.CONCLUSIONS: HHP‐assisted pectinase treatment could be used as novel technique for the modification of pectin to give better emulsifying properties with great potential for application in the food industry. © 2020 Society of Chemical Industry