Partial substitution of wheat flour with Flammulina velutipes powder (FVP) or soluble polysaccharide (SPFV) at different addition levels, and the effects of which on the rheological and microstructural properties of dough were investigated. FVP significantly (P < 0.05) increased the water absorption but decreased the development time and stability of dough significantly (P < 0.05). Furthermore, it was capable of providing a weaker extension and harder dough with the increasing of FVP addition levels. FVP increased the storage (G′) and loss (G″) moduli, while the tan δ decreased with the increasing of FVP addition levels. However, SPFV addition had inconsistent viscoelastic results with that of FVP addition. The microstructure of dough showed that the continuity of gluten networks had been disrupted by FVP and SPFV at a higher addition level. This research could provide a foundation for the application of FVP in wheat-flour foods, and FVP addition levels of 2.5% to 5.0% are recommended.
Adding a certain proportion of Pleurotus eryngii can improve the nutritional value of wheat-flour foods and enhance the utilization of this mushroom. In this research, partial wheat flour was substituted with P. eryngii powder (PEP) or soluble polysaccharide (SPPE) at different addition levels, and the effects of PEP and SPPE on the rheological and microstructural properties of dough were investigated. Farinographic assay results suggested that PEP significantly (p < 0.05) increased the water absorption of wheat flour but decreased the development time and stability of dough significantly (p < 0.05). Furthermore, it was capable of providing weaker extensographic characteristics and harder dough with the increasing of PEP addition levels. The dynamic oscillatory tests indicated that the PEP addition approximately increased the storage (G') and loss (G″) moduli in the entire frequency range, while the tan δ roughly decreased with the increasing of PEP addition levels, which could be attributed to the low solubility and strong water-trapping capacity of the dietary fiber in PEP. Due to the good water solubility and easy formation of hydrogen bonds, the addition of SPPE had inconsistent results with the PEP addition. The inner microstructure of dough showed that the continuity of gluten networks had been disrupted by PEP and SPPE addition and then resulted in a weaker extension and harder dough. This research could provide a foundation for the application of PEP in wheat-flour foods, and PEP addition levels of 2.5%-5.0% are recommended.
The influence of boiling time (10 –120 min) on nutritional and antioxidant properties of Lentinus edodes pieces and broth was investigated. The results showed that the primary nutrients contents and antioxidant activities of L. edodes pieces decreased with the prolongation of boiling time, while ergosterol content increased. The nutrients contents in L. edodes broth presented an uptrend, and the antioxidant activities increased rapidly in the first 30 min, and then kept stable or decline, which was positively correlated with the change of total phenolic content. Microstructure observation showed that boiling treatment destroyed the cell wall of L. edodes, leading to the dissolution and loss of cell wall components and cytoplasmic contents. From the point of nutrition, the optimal boiling time for L. edodes pieces is 30 min and for broth preparation is 60 min. This study provides a useful reference for rational cooking or processing L. edodes and other mushrooms.