Dynamic changes of proton populations in potato flours during fermentation and their relationship with digestibility and functional properties

Changes in the structural and physicochemical characteristics of sonicated potato flour

Ultrasound has been widely used for physical modifications of starch because of its effectiveness and environment friendliness; however, only a few reports have focused on the effect of varying ultrasonic treatments on the physicochemical properties of potato flour. In the present study, ultrasound at varying power levels (200, 300, 400, 500, and 600 W) and time intervals (20, 40, 60, 80, and 100 min) were used to obtain sonicated flour. Sonicated potato flour exhibited a significant (P < 0.05) decrease in blue value and oil holding capacity but an increase in swelling power, water solubility, syneresis rate, and transparency. Moreover, ultrasound decreased the RDS content while increasing RS and SDS contents. Thermal properties demonstrated significant (P < 0.05) increases in T0 (64.39℃-83.52℃) and TC (144.29℃-146.87℃) but a decrease in ΔH of the sonicated flour. SEM revealed wrinkles, less debris, and larger particle size at the surface of the sonicated flour. FTIR profiles of all samples exhibited similar characteristics peaks, but the sonicated flour had a higher R1047/1022 value. Additionally, ultrasound did not affect crystalline patterns, but it increased the crystallinity of the sonicated flour. Our study contributes to the understanding of physicochemical property changes of sonicated potato flour, which could have industrial applications.

Enhance Production of γ-Aminobutyric Acid (GABA) and Improve the Function of Fermented Quinoa by Cold Stress

Quinoa is an excellent source of γ-aminobutyric acid (GABA), which is a natural four-carbon non-protein amino acid with great health benefits. In this study, the quinoa was treated by cold stress before fermentation with Lactobacillus plantarum to enhance the amount of GABA. The best Lactobacillus plantarum for GABA production was selected from sixteen different strains based on the levels of GABA production and the activity of glutamic acid decarboxylase (GAD). Cold stress treatments at 4 °C and at -20 °C enhanced the amount of GABA in the fermented quinoa by a maximum of 1191% and 774%, respectively. The surface of the fermented quinoa flour treated by cold stress showed more pinholes, mucus, faults and cracks. A Fourier transform infrared spectrophotometer (FTIR) analysis revealed that cold stress had a violent breakage effect on the -OH bonds in quinoa and delayed the destruction of protein during fermentation. In addition, the results from the rapid visco analyzer (RVA) showed that the cold stress reduced the peak viscosity of quinoa flour. Overall, the cold stress treatment is a promising method for making fermented quinoa a functional food by enhancing the production of bioactive ingredients.

Therapeutic and Prebiotic Effects of Five Different Native Starches on Dextran Sulfate Sodium-Induced Mice Model of Colonic Colitis

SCOPE

The availability of studies related to the effects of natural macronutrients on inflammatory bowel disease (IBD) remain relatively limited. This study investigates whether and to what extent the consumption of five different native starches alleviate the clinical symptoms and dysbiosis of gut microbiota associated with colitis.

METHODS AND RESULTS

Using dextran sodium sulfate (DSS)-induced mouse model of colitis, the potential effects of native potato starch (PS), pea starch (PEAS), corn starch (CS), Chinese yam starch (CYS), and red sorghum starch (RSS) on the clinical manifestations and dysbiosis of gut microbiota are studied. Compared to CS and RSS, the consumption of PEAS, PS, and CYS significantly diminishes clinical enteritis symptoms, including reduced disease activity index, and the alleviated degree of colonic histological damage. Furthermore, the analysis of gut microbiota reveals the significant prebiotic characteristics of PEAS, PS and CYS, as indicated by the maintenance of gut microbiota hemostasis and the inhibition of typically pathogenic bacteria, including Escherichia coli and Helicobacter hepaticus.

CONCLUSION

Starches from potato, pea, and Chinese yam alleviate colitis symptoms in a mouse model, and also show significant prebiotic characteristics. These findings suggest a cost-effective and convenient dietary strategy for the management of IBD.