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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]

BACKGROUND: Baijiu brewing adopts the solid‐state fermentation method, using starchy raw materials, Jiuqu as saccharifying fermenting agent, and distilled spirits made by digestion, saccharification, fermentation and distillation. In the late stages of solid‐state fermentation of Baijiu, the reduced activity of glucoamylase leads to higher residual starch content in the Jiupei, which affects the liquor yield. The direct addition of exogenous glucoamylase leads to problems such as the temperature of the fermentation environment rising too quickly, seriously affecting the growth of microorganisms. RESULTS: To solve the problem of reduced activity of glucoamylase in the late stage of solid‐state fermentation of Baijiu, microcapsule beads (M‐B) based on microcapsule emulsion were prepared and the effect of M‐B on solid‐state fermentation of Baijiu was investigated. The results showed that the release of M‐B before and after drying was 53.27% and 25.77% in the liquid state (120 h) and 29.84% and 22.62% in the solid state (15 days), respectively. Adding M‐B improved the alcohol by 0.33 %vol and reducing sugar content by 0.51%, reduced the residual starch content by 1.21% of the Jiupei, and had an insignificant effect on the moisture and acidity of the Jiupei. CONCLUSION: M‐B have excellent sustained‐release properties. The addition of M‐B in solid‐state fermentation significantly increased the alcohol content, reduced the residual starch content of Jiupei, ultimately improving the starch utilization rate and liquor yield of Baijiu brewing. The preparation of M‐B provides methods and approaches for applying other active substances and microorganisms in the brewing of Baijiu. © 2023 Society of Chemical Industry. [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]

Glucoamylase is one of the most widely used enzymes in industry, but the development background and existing circumstances of industrial glucoamylase were not described by published articles. CiteSpace, a powerful tool for bibliometric, was used to analyze the past, existing circumstances, and trends of a professional field. In this study, 1820 Web‐of‐Science‐indexed articles from 1991 to 2021 were collected and analyzed by CiteSpace. The research hotspots of industrial glucoamylase, like glucoamylase strain directional improvement, Aspergillus niger glucoamylase, glucoamylase immobilization, application of glucoamylase in ethanol production, and "customized production" of porous starch, were found by analyzing countries, institutions, authors, keywords, and references of articles. Practical applications: The research progress of glucoamylase with industrial potential was analyzed by CiteSpace, and a significant research direction of glucoamylase with industrial potential was found. This is helpful for academic and corporate audiences to understand the current situation of glucoamylase with industrial potential and carry out follow‐up works. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Fern root starch has a high percentage of amylose and has great potential for application in the field of slow‐digesting foods. Clarifying the effect of treatment conditions on fern root starch is key to achieving industrialized production of fern root resistant starch. In the present study, fern root starch was treated by the autoclave‐enzymatic method with pullulanase, glucoamylase and mixed enzyme.The content of resistant starch in fern roots treated with mixed enzyme was the highest (24.07 ± 1.11%), which was approximately 320% times that of the native starch, had the best water‐holding capacity (151.08%), vital transparency and freeze–thaw stability. By contrast, the solubility, swelling and viscosity were lower than natural starch. In addition, mixed enzyme shows a denser structure, and the crystal form changes from C‐type to V‐type, with a high relative crystallinity and significantly enhanced thermal stability.After mixed enzyme combined with autoclave treatment, the content of resistant starch in fern root was greatly increased. The modified starch molecules did not produce new functional groups, which made the crystal structure of starch molecules more compact, and resistance to enzymatic hydrolysis and high temperature thermal stability were significantly enhanced. This provides a positive reference for further in‐depth study of fern root starch, improvement of utilization value, development and innovation of new food health products, and diabetes treatment. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]