The Heat-Induced Gel–Sol Transition in Coated Tofu: A Study on Protein Conformation and Microstructural Changes
Abstract
1. Introduction
2. Results and Discussion
2.1. Protein Solubility
2.2. The Protein Composition Was Analysed Using Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE)
2.3. Surface Hydrophobicity
2.4. Fourier Transform Infrared (FTIR) Spectroscopy Was Used to Analyse Changes in Secondary Structure
2.5. Fluorescence Spectroscopy Was Employed to Analyse Changes in the Tertiary Structure of Proteins
2.6. Intermolecular Forces
2.7. Free Sulfhydryl Groups
2.8. Scanning Electron Microscopy (SEM) Was Used to Analyse Microstructural Changes
3. Conclusions
4. Materials and Methods
4.1. Materials
4.2. Preparation of Coated Tofu
4.3. Heat Treatment of Coated Tofu
4.4. Determination of Soluble Protein Content
4.5. Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE)
4.6. Surface Hydrophobicity Measurement
4.7. Fourier Transform Infrared Spectroscopy
4.8. Fluorescence Spectrometry
4.9. Determination of Intermolecular Force
4.10. Determination of Free Sulphhydryl Groups
4.11. Scanning Electron Microscopy
4.12. Statistics and Analysis
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Temperature-Time (°C-min) | α’ | α | β | A | B |
---|---|---|---|---|---|
160-6 | 10.20% | 11.69% | 9.26% | 17.89% | 20.90% |
160-9 | 10.34% | 11.58% | 9.20% | 17.66% | 20.41% |
160-12 | 10.18% | 11.72% | 9.30% | 17.61% | 20.18% |
160-15 | 10.20% | 11.50% | 9.29% | 17.21% | 20.20% |
160-18 | 10.11% | 11.79% | 9.47% | 17.08% | 19.54% |
170-6 | 10.10% | 11.65% | 9.30% | 17.50% | 20.35% |
170-9 | 10.83% | 11.72% | 9.27% | 17.44% | 20.65% |
170-12 | 10.70% | 11.44% | 9.44% | 17.25% | 19.80% |
170-15 | 10.20% | 11.76% | 9.59% | 17.09% | 19.29% |
170-18 | 10.45% | 11.20% | 9.83% | 16.96% | 19.20% |
180-6 | 10.41% | 11.22% | 9.63% | 17.49% | 19.96% |
180-9 | 10.65% | 11.45% | 9.86% | 17.41% | 19.61% |
180-12 | 10.15% | 11.81% | 9.89% | 17.17% | 19.75% |
180-15 | 10.87% | 11.62% | 9.79% | 17.12% | 19.16% |
180-18 | 10.83% | 11.58% | 9.61% | 16.92% | 18.87% |
190-6 | 10.79% | 11.01% | 9.43% | 17.16% | 18.74% |
190-9 | 10.57% | 11.85% | 9.26% | 16.57% | 16.20% |
190-12 | 10.76% | 11.75% | 9.30% | 15.77% | 15.17% |
190-15 | 10.60% | 11.74% | 9.32% | 15.06% | 13.99% |
190-18 | 10.70% | 11.75% | 9.19% | 14.53% | 13.05% |
200-6 | 10.65% | 11.49% | 9.00% | 17.80% | 17.93% |
200-9 | 10.70% | 11.46% | 8.68% | 14.97% | 13.33% |
200-12 | 10.56% | 11.50% | 8.91% | 9.67% | 11.31% |
200-15 | 10.68% | 11.52% | 8.75% | 7.89% | 9.02% |
200-18 | 10.59% | 11.53% | 8.89% | 8.14% | 9.43% |
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Xie, X.; Li, M.; Diao, X.; Sun, S.; Wen, M.; Zhou, X.; Zhao, L.; Li, Y.; Lv, P.; Li, B.; et al. The Heat-Induced Gel–Sol Transition in Coated Tofu: A Study on Protein Conformation and Microstructural Changes. Gels 2025, 11, 237. https://doi.org/10.3390/gels11040237
Xie X, Li M, Diao X, Sun S, Wen M, Zhou X, Zhao L, Li Y, Lv P, Li B, et al. The Heat-Induced Gel–Sol Transition in Coated Tofu: A Study on Protein Conformation and Microstructural Changes. Gels. 2025; 11(4):237. https://doi.org/10.3390/gels11040237
Chicago/Turabian StyleXie, Xin, Meng Li, Xinrui Diao, Saihua Sun, Ming Wen, Xiaohu Zhou, Liangzhong Zhao, Yang Li, Ping Lv, Bin Li, and et al. 2025. "The Heat-Induced Gel–Sol Transition in Coated Tofu: A Study on Protein Conformation and Microstructural Changes" Gels 11, no. 4: 237. https://doi.org/10.3390/gels11040237
APA StyleXie, X., Li, M., Diao, X., Sun, S., Wen, M., Zhou, X., Zhao, L., Li, Y., Lv, P., Li, B., Shen, X., Huang, Z., Chen, H., & Zhang, K. (2025). The Heat-Induced Gel–Sol Transition in Coated Tofu: A Study on Protein Conformation and Microstructural Changes. Gels, 11(4), 237. https://doi.org/10.3390/gels11040237