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In this study, microcapsule beads‐0–3‐layers (M‐0–3 indicates microencapsulated beads with 0, 1, 2, and 3 layers) were prepared, their properties were measured and characterized, and the effects of M‐0–3 on solid‐state fermentation were investigated. The results showed that in a liquid environment, the releasing glucoamylase activities of M‐0–3 were 55.77%, 47.67%, 45.85%, and 42.87% in 360 h, respectively. In the solid environment, the reducing sugar production efficiency of M‐0–3 was 29.84%, 27.72%, 19.16%, and 15.93% in 15 days, respectively. Adding M‐0–3 improved the alcohol and reduced sugar content while decreasing the residual starch content of the Jiupei, indicating that adding M‐0–3 was beneficial to the solid‐state fermentation of Baijiu. Solid‐state fermentation simulation experiments illustrated that microcapsule beads play a positive role in the production of Baijiu, enhancing raw material utilization and yield of Baijiu production. [ABSTRACT FROM AUTHOR]

The glucoamylase@ZIF‐8 was prepared using ZIF‐8 material as the carrier in this study. The preparation process was optimized by response surface methodology, and the stability of glucoamylase@ZIF‐8 was determined. The material was characterized by scanning electron microscopy, X‐ray diffraction, and Fourier transform infrared spectroscopy. The results showed that the optimum preparation process of glucoamylase@ZIF‐8 was 1.65 mol 2‐methylimidazole, 5.85 mL glucoamylase, 33°C stirring temperature, 90 min stirring time, and 84.0230% ± 0.6006% embedding rate. At 100°C, the free glucoamylase completely lost its activity, whereas the glucoamylase@ZIF‐8 still had a retained enzyme activity of 12.0123% ± 0.86158%; at pH 3–6, the highest activity of glucoamylase@ZIF‐8 was 95.9531% ± 0.96181%, and about 80% of glucoamylase activity could be retained under alkaline conditions. When the ethanol concentration was 13%, the retained enzyme activity was 7.9316% ± 0.19805%, significantly higher than free enzymes. The Km of glucoamylase@ZIF‐8 and free enzyme were 1235.6825 and 80.317 mg/mL, respectively. Vmax was 0.2453 and 0.149 mg/(mL min), respectively. The appearance, crystal strength, and thermal stability of glucoamylase@ZIF‐8 were improved after optimization, and they had high reusability. [ABSTRACT FROM AUTHOR]

Glucoamylase was often used in the brewing industry but was unstable to several environmental factors and reacted quickly to produce fermentable sugar, which limited its applications. Microencapsulation could effectively overcome the drawbacks. This study evaluated the feasibility of the preparation of glucoamylase microcapsules (GM) using W/O/W complex coacervation‐freeze‐drying method. The parameters of the microcapsules were optimized by the response surface optimization design: core‐wall ratio at 1:1, wall‐material concentration at 8%, and coagulation time for 20 min. Under current condition, the final microencapsulation efficiency reached 85.64 ± 1.60%. Glucoamylase could be slowly released for more than 96 h in the liquid state, and could react slowly for more than 336 h in the solid state. The optimized GM were incubated for 1 h, and the relative enzyme activity was better than that of free glucoamylase under high temperature conditions. The water capacity, solubility, morphology, differential scanning calorimetry, and Fourier transform infrared spectroscopy were conducted. Glucoamylase exhibited good sustained release characteristics. The microcapsules were more resistant to environmental stimuli and showed stronger robustness after optimization. Practical Application: Saccharification enzymes are often used in the winemaking industry, and direct addition will cause the fermentation process to heat up too quickly, resulting in the inactivation of microorganisms and saccharification enzymes, affecting the efficiency of saccharification enzymes. Therefore, microcapsules are used to encapsulate the saccharification enzyme, and its efficacy is slowly released for a long time during the fermentation process. [ABSTRACT FROM AUTHOR]