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Daqu is a typical multi-enzyme and multi-microbes fermentation starter of traditional Chinese liquor. The culture-independent molecular method has become a general method for the study of the Daqu microbial community. To determine the most suitable DNA extraction method of Daqu samples, the effects of different DNA extraction methods on Daqu genomic DNA extraction and amplicon libraries were evaluated. In this study, four DNA extraction methods were selected for the extraction of microbial DNA from two kinds of Daqu. Combined with DNA extraction quality, qPCR quantitative results, Illumina Miseq sequencing results of bacterial 16S rRNA gene, and fungal ITS gene amplicon library, the effects of different extraction methods of Daqu genomic DNA were evaluated. The comprehensive analysis of DNA yield and microbial biomass showed that the DNA yield of the SDS-based extraction method was higher than that of the kit extraction method, and the DNA yield of the in-situ SDS-based extraction method was as high as 5.46 x 104 ng/g, but the DNA purity was low. The qPCR quantitative results of the SDS-based extraction method were 101 - 6 orders of magnitude higher than those of the kit extraction method, and the microbial biomass of the washing-pretreatment plus SDS-based extraction method was the highest, which was 101-3 orders of magnitude higher than that of the in-situ SDS-based extraction method. Whereas the microbial biomass of the DNA extraction kit was the lowest, with only 102-4of the Shannon diversity index among amplicon libraries showed that different DNA extraction methods had significant differences among fungal ITS amplicon libraries, but no significant differences among bacterial 16S rDNA amplicon libraries. The Shannon index of the fungal amplicon library of the washing-pretreated samples were higher than that of the in-situ treated samples. By comparing the operational taxonomic units (OTU) with significant differences among the amplicon libraries, it could be seen that most of the OTUs in the bacterial 16S rDNA amplicon library had differences in abundance, but most of them could be detected in different DNA extraction methods. However, among the fungal ITS amplicon libraries, most OTUs showed a similar trend between different DNA extraction methods, indicating that the DNA extraction method had a significant effect on the extraction of some fungal microbial genomes, and the washing-pretreatment was beneficial to the extraction of fungal genomic DNA. Compared with the four DNA extraction methods, the washing-pretreatment plus SDS-based extraction method was the most suitable for the quantitative and community structure analysis of Daqu microorganisms. [ABSTRACT FROM AUTHOR]

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]

Background and Objectives: Mashing temperature is important during beer brewing processes. Qingke malt was a new material whose application in the beer industry holds significant importance for the beer industry and agriculture development in the Qinghai–Tibet Plateau. The objective of this study was to investigate the effects of mashing temperature on the physicochemical parameters, fermentation capacity, and antioxidant capacity of Qingke wort. Findings: Ethanol production and the real degree of fermentation decreased with increasing the temperature—S, while the real extract increased with increasing the temperature—S. A lower temperature—S proved to be more advantageous for the fermentation capacity of Qingke wort. In addition, a positive correlation between reducing power and the temperature—P and a negative correlation between the 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonate) free radical scavenging activity and the temperature—S were found. Conclusion: The fermentation capacity of Qingke wort was obtained the best when the temperature—P was 50°C and the temperature—S was 60°C. The antioxidant capacity of Qingke wort was satisfactory; the best was obtained when the temperature—P was 45°C and the temperature—S was 60°C. Significance and Novelty: This is the first study to investigate the mashing characteristics of Qingke wort under different mashing temperatures. The results show that β‐glucan content was abundant in Qingke wort and was positively correlative with the temperature—S. [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]

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]

Craft beer brewers need to learn process control strategies from traditional industrial production to ensure the consistent quality of the finished product. In this study, FT-IR combined with deep learning was used for the first time to model and analyze the Plato degree and total flavonoid content of Qingke beer during the mashing and boiling stages and to compare the effectiveness with traditional chemometrics methods. Two deep learning neural networks were designed, the effect of variable input methods on the effectiveness of the models was discussed. The experimental results showed that the CARS-LSTM model had the best predictive performance, not only as the best quantitative model for Plato in the mashing (R 2 p = 0.9368) and boiling (R 2 p = 0.9398) phases but also as the best model for TFC in the boiling phase (R 2 p = 0.9154). This study demonstrates the great potential of deep learning and provides a new approach to quality control analysis in beer brewing., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)