Selectively hydrolyzed soy protein as an efficient quality improver for steamed bread and its influence on dough components

Five different extruded soy protein isolates (ESPIs) were obtained by extrusion and denoted by IVD1, IVD2, IVD3, IVD4, and IVD5. Then the SDS-PAGE results showed that the subunits of SPI decreased after extrusion, especially the subunits of 90.8, 32.8, and 31.3 kDa, whereas no isopeptide bond was formed. Although SPI improved both the development time (DT) and stability (S) of dough, ESPIs increasedSbut the DT decreased from 4.3 min to 1.8–2.0 min. Texture profile analysis (TPA) results showed that the hardness and chewiness of Chinese steamed bread (CSB) decreased in the order wheat flour+IVD2 (WF+IVD2), WF+SPI, WF+IVD4, WF+IVD1, WF+IVD3, WF, and WF+IVD5. As regards color, the total colorΔEdecreased except for the WF+IVD1 (56.22); its positive and negative trends ofL⁎andb⁎were invariant with the SPI or ESPIs mixture, whereasa⁎showed a positive trend. The sensory score increased from 82.7 to 83.4 with 3% of SPI addition and up to 87.8 when the substitution was IVD1. Therefore, SPI treated by extrusion may significantly improve the quality of CSB.

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Comparison of Two Soy Globulins on the Dynamic-Mechanical Properties of the Dough and the Quality of Steamed Bread

Journal of Chemistry ◽

10.1155/2016/5323745 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Xue-Li Gao ◽

Fu-Sheng Chen ◽

Li-Fen Zhang ◽

Guan-Hao Bu ◽

Ming-Tao Fan

Keyword(s):

Soy Protein ◽

Loss Modulus ◽

Dynamic Mechanical Properties ◽

Dynamic Mechanical Analyzer ◽

Mixing Properties ◽

Texture Profile ◽

Dynamic Mechanical ◽

Wheat Dough ◽

Steamed Bread

To investigate the effect of the soy protein concentrate (CSP) and 7S and 11S soy globulin on wheat dough and steamed bread (SB), mixing properties of the dough were assessed by farinograph and dynamic-mechanical analyzer (DMA). The quality attributes of SB were assessed by texture profile analyzer (TPA), sensory analysis, and scanning electron microscope (SEM). The results showed that CSP, 7S, or 11S (each from 2.0 to 4.0%) significantly decreased gluten content (from 29.4 to 26.0, 36.7 to 31.8, and 31.6 to 30.7%), when those were added to wheat flour. The CSP/wheat dough stability was increased (from 6.5 to 8.4, 6.5 to 8.5, and 6.5 to 8.3 min) and the degree of softening was decreased (from 71.0 to 68.0, 71.0 to 64.0, and 71.0 to 62.0 min), but 7S or 11S had the opposite result. Moreover, the ratio of 7S and 11S has a significant effect on the quality of the dough. The storage modulus and loss modulus of soy/wheat dough decreased in the order of CSP, control, 11S soy globulin, and 7S soy globulin. The hardness, chewiness, and cohesiveness of SB decreased in the order of control, CSP, 11S soy globulin, and 7S soy globulin. Microstructure demonstrated that gluten network was interfered by SPC, 7S, and 11S soy protein, which was in agreement with the texture analysis index. The quality of SB with 3% 11S was the best in texture, microstructure, and sensory. These findings indicate that 11S has the potential to be used as a special soy protein for SB making.

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