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Pullulan-Jiuzao glutelin (JG) conjugates (PJCs) were prepared via Maillard reaction in this study. PJCs were prepared by optimizing pullulan to JG ratios (0.5:1, 1:1, 2:1, and 4:1, expressed as PJC-0.5, PJC-1, PJC-2, and PJC-4, respectively) and reaction times (0-180 min) at pH 7 and 11. The secondary structure changes of PJC compared to JG, potential conjugation sites between pullulan and JG, PJC emulsifying properties, in vitro antioxidant activities, and interaction with curcumin (CUR) were investigated. Among the four PJCs, PJC-2 obtained after 180 min reaction at pH 11 and 90 °C exhibited the best ability in nano-emulsion stabilization with the lowest particle size (180-200 nm and 290-450 nm against NaCl during storage), PDI (0.2-0.4 and 0.4-0.7 against NaCl during storage), highest zeta-potential (-20.10 mV), and lowest backscattering intensity. The spontaneous conjugation binding sites between pullulan and JG were Arg-39, Arg-54, and Asp-168. In contrast to native JG, PJC-2 exhibited better antioxidant capacities, low toxicity for CCD 841 CON and Caco-2 cells, and enhancement of antioxidant enzyme content (i.e., SOD, GPX, and CAT) after AAPH-induced oxidative stress. In addition, there exists an interaction between CUR and PJC-2 by residues Ala-74, Asp-376, Arg-368 and -374, Val-45, and Ala-44 of JG. The results above exhibit important implications for the fabrication of PJC-stabilize nano-emulsion and even for developing PJC product as a potential carrier of CUR in the functional food industry.

A high glycaemic index diet causes a rapid increase in blood sugar level and may lead to chronic metabolic disorders such as obesity and type 2 diabetes. Shiitake is rich in bioactive compounds. Wheat flour noodles were enriched with shiitake (Lentinus edodes) powder (cap, stem, whole) at different levels to investigate the effects of shiitake addition on the nutritional composition, physical and textural properties. In vitro digestion was conducted to determine the glycaemic glucose equivalents and bioaccessibility of antioxidants in digesta. The addition of 15% shiitake stem powder in the noodles resulted in a significant (p < 0.05) decrease in reducing sugars released after in vitro digestion. Digesta also exhibited cellular antioxidant ability on IEC-6 cells after H2O2-induced oxidative stress. These results show the potential beneficial use of shiitake, especially the stem, as a high-value ingredient to improve the nutritional profile and reduce the glycaemic index of foods.

The objective of this study was to determine the effects of soluble dietary fibre inclusion on milk coagulation kinetics. Three fibre ingredients gum acacia, inulin or pectin were added to milk prior to addition of rennet. Milk coagulation was monitored using a controlled stress rheometer, NIR transmission sensor and a hot wire sensor. Gel times and coagulum firming rates were determined from the sensor response characteristics. Gel microstructure was examined using confocal scanning laser microscopy. Gum acacia (1–3% (w/w)) significantly decreased gel times and coagulum firming times and these gels had more open casein networks than the control gels. A 2% (w/w) addition of inulin was required to decrease gel time and coagulum firming time and no discernable difference was observed between the inulin enriched and control gels. Pectin (0.2–0.4% (w/w)) significantly reduced gel times. Above 0.2% (w/w), added pectin increased coagulum firming times and resulted in a limited casein network developing.