A green and efficient ultrasound-assisted deep eutectic solvent (UDE) method was developed for the first time to extract beta-glucan-rich polysaccharides from highland barley distiller's grains (HBDG), a major by-product of Baijiu production. Under optimized conditions (choline chloride:lactic acid at a 1:4 M ratio, water content 49%, solid-to-liquid ratio 1:33 g/mL, 79 degrees C, 120 min), the beta-glucan extraction rate reached 55.78%. Systematic comparison with the polysaccharides obtained by hot water extraction (HWE-G) and ultrasound-assisted extraction (UAE-G) revealed that the polysaccharide prepared by UDE extraction (UDE-G) exhibited the lowest molecular weight (68.1 kDa) and viscosity (0.97 mPa & centerdot;s), which correlated with superior antioxidant (ROS scavenging in Raw264.7 cells) and hypoglycemic (alpha-amylase/alpha-glucosidase inhibition, and glucose dialysis retardation index) activities. Notably, UDE-G contained the highest beta-glucan content (83.65%), whereas HWE-G and UAE-G contained only 20.89% and 19.11%, respectively. Mechanistically, the enhanced bioactivity of UDE-G is attributed to its lower molecular weight (68.1 vs. 110.8 kDa for HWE-G), higher glucose molar ratio (82.41% vs. 19.50% for HWE-G), and the retention of its essential beta-glucan structural features, which collectively facilitate better cellular uptake and radical neutralization. This study positions UDE as a green and efficient extraction strategy for valorizing HBDG and highlights UDE-G as a promising functional ingredient for managing hyperglycemia and oxidative stress.

Highland barley Baijiu is a kind of fermented liquor with national characteristics produced in the Qinghai-Tibet Plateau, and its quality largely depends on the highland barley Baijiu Daqu (HBQ). HBQ contains abundant microbial resources and embedded unknown genomes that have not yet been decoded. In order to deeply understand the key contribution of microorganisms in HBQ, this study analyzed the microbial community structure of HBQ, inferred predicted functions and recovered high-quality metagenome-assembled genomes (MAGs) based on Metagenomics. The results indicated that Pantoea agglomerans was the most abundant species in HBQ, followed by Lichtheimia ramosa, Pichia kudriavzevii, Saccharomycopsis fibuligera and Wickerhamomyces anomalus. The predictive function of the HBQ was focused on annotating carbohydrate metabolism and amino acid metabolism. Meanwhile, six high-quality MAG strains were recovered and identified as Unclassified Kroppenstedtia, Erwinia persicina, Leuconostoc citreum, Saccharopolyspora rectivirgula, Levilactobacillus brevis, and Pantoea agglomerans. Genome annotation of the recovered genomes showed eggNOG predicted function as well as primary and secondary metabolites. The metabolic network diagram of the functional microorganisms in HBQ related to flavor compounds was also predicted. The results can help to understand the formation mechanism of flavor profiles in highland barley Baijiu.

In this study, the electronic tongue, electronic nose, GC-MS, and GC-IMS technologies were used to analyze the raw materials, Daqu, and raw liquor of Qingke Baijiu throughout the entire brewing process. Similar to other alcoholic beverages, esters and alcohols were the main volatile flavor components. It was worth noting that in these samples, benzaldehyde and ethyl palmitate were the common aroma components. Among them, benzaldehyde had a toasted flavor, and ethyl palmitate had a waxy aroma. Important flavor compounds were identified based on their odor activity values (OAVs), while variable importance in projection (VIP) scores helped identify the different compounds. The biosynthesis pathways of important flavor compounds in Qingke Baijiu primarily involve butyrate metabolism, glycolysis, gluconeogenesis, phenylalanine metabolism, and fatty acid elongation. The results can not only deepen the understanding of the characteristics of aroma compounds and the flavor formation mechanism of Qingke Baijiu, but also provide scientific basis for optimizing the production process and improving the aroma of Qingke Baijiu.

Qingke (Highland barley) baijiu is a characteristic alcoholic beverage in plateau regions. It has garnered significant attention owing to its unique brewing technology, distinctive flavor profile and potential health benefits. Qingke Daqu is not only a saccharifying agent and fermenting agent for Qingke baijiu, but also an important raw material and microbial source. Additionally, it serves as a key source of flavor substances and their precursor substances. In this work, a total of 38 aroma-active compounds were identified in Qingke Daqu by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) and aroma extract dilution analysis (AEDA). Among these aroma-active compounds, 2,3-butanedione, vanillin and isovaleric acid exhibited the highest FD values. After quantification, 15 aroma-active compounds had odor activity values (OAVs) > 1 in Qingke Daqu. Among them, 2,3-butanedione, hexanal and ethyl caproate were identified as the critical aroma-active compounds in Qingke Daqu. In addition, the physicochemical indicators of Qingke Daqu were determined. Among these, the content of starch was the highest, while content of fatty acid was the lowest. Correlation analysis further reveals that, starch has the strongest association with key aroma-active compounds in Qingke Daqu, with the largest number of compounds exhibiting a positive correlation. This work can provide data support for the scientific expression of Qingke Daqu.

Qingke baijiu (QKJ), also known as Highland barley wine, is a traditional Chinese fermented baijiu from the Tibetan Plateau. It is a kind of light-aroma baijiu (LAJ) with a unique flavor distinct from other LAJs produced using Daqu. In this work, QKJ and other LAJs (Daqu) were selected for comparison of their aroma differences using a molecular sensory approach. In total, 66 aroma compounds in QKJ and 73 in LAJ were identified via gas chromatography-olfactometry-mass spectrometry (GC-O-MS). After quantification, odor activity values (OAVs) calculation and orthogonal partial least squares discriminant analysis (OPLS-DA), ethyl butyrate, ethyl hexanoate, furfuryl alcohol and ethyl isobutyrate were recognized as the major aroma compounds distinguishing QKJ from LAJ. Further recombination and omission experiments revealed ethyl hexanoate, ethyl valerate, gamma-nonanolactone, ethyl acetate and benzeneacetaldehyde diethyl acetal as critical aroma components in QKJ. This work provides valuable insights into the flavor and quality control of Chinese baijiu.

Daqu plays a crucial role in Qingke Baijiu production by providing essential raw materials, microorganisms, and enzymes for fermentation. In order to further investigate the impact of microorganisms and enzymes in Qingke Baijiu Daqu, the physicochemical properties, dominant microorganisms, as well as enzyme system composition of Qingke Baijiu Daqu were studied. The results revealed 8 dominant bacterial genera and 4 dominant fungal genera in Daqu. Through the analysis of metaproteomics, 422 enzyme proteins were identified, including 121 oxidoreductases, 108 transferases, 74 hydrolases, 33 lyases, 41 isomerases, 32 ligases and 13 translocase. The activity of key enzymes in the main metabolic pathways of Daqu was measured, and it was found that the activity of saccharifying enzyme was the highest, which was the primary hydrolase of Daqu. Finally, correlation analysis showed that Erwinia was positively correlated with saccharification power. This study can provide valuable insights for controlling the quality of Daqu and Qingke Baijiu.

To create the low-alcoholic fermented wine with excellent nutritional properties, this study explored the dynamic changes in organic acids, amino acids and microbial communities during the fermentation of highland barley wine (HBW) and their correlation. A total of 7 organic acids and 16 amino acids were detected in HBW at different fermentation time. Partial least squares-discriminant analysis (PLS-DA) showed that lactic acid, acetic acid, arginine, proline and glutamate were the characteristic metabolites. Acetobacter, Leuconostoc, Weissella, Lactobacillus, Rhizopus, Saccharomyces and Pichia were the dominant genera throughout the fermentation progress. Microbial communities were highly correlated with the changes of reducing sugar, pH and titratable acidity. Pearson correlation analysis showed that Acetobacter, Lactobacillus, Rhizopus, Saccharomyces and Aspergillus were correlated with the content of organic acids and amino acids. Pyruvate metabolism and Glycolysis/Gluconeogenesis played important roles in the formation of metabolites in HBW. This study could not only provide a theoretical guidance for a deeper understanding of the correlations between microbial communities and the generation of organic acids and amino acids during the fermentation of HBW, but also help to screen beneficial microbial strains for high-quality HBW brewing.

Icefish (Salangidae) is a valuable aquatic product that is often dried for preservation. The purpose of this study was to investigate the effect of different drying methods on the rehydration quality of icefish. Low-field nuclear magnetic resonance (LF-NMR) was used to compare the rehydration rate, moisture migration and distribution of icefish dried by cold air (8, 10, 12 degrees C) and hot air (40, 50, 60 degrees C) The muscle fibers structure of dried icefish and magnetic resonance imaging (MRI) of icefish after rehydration were examined. The results showed that cold air drying resulted in higher values of these parameters than hot air drying. MRI analysis revealed that cold air dried icefish retained more water after rehydration than hot air dried icefish. The T2 transverse relaxation spectra of rehydrated icefish exhibited three peaks corresponding to bound water, immobilized water and free water. The proportion of immobilized water increased significantly and accounted for more than 92% after rehydration, while the proportion of free water was around 2%-3%. Cold air drying preserved the muscle fiber structure and protein network better than hot air drying, which improved the rehydration quality of icefish. The study provides theoretical and data support for using cold air drying technology in aquatic product processing.Practical applicationsThe focus of this study is to compare the effect of different drying methods on the rehydration rate of icefish. The results indicate that part of the bound water migrated to the immobilized water during the initial stage of rehydration, which increased the content of immobilized water and reduced the binding force of some bound water. The T2 value shifts to the right in all groups, indicating that the binding force between biological macromolecules (such as myofibrillar protein) and icefish water was weakened. Different drying methods have a significant impact on changes in the internal water status of rehydrated icefish samples. Our results suggest that cold air drying is a better method for drying icefish compared to hot air drying, as it improves its rehydration quality. The findings of this study can be useful for food industry personnel who are involved in fish processing, preservation, and nutrition. Hot air drying causes more damage to the muscle fibers of icefish than cold air drying, which have a significant impact on changes in water status of rehydrated icefish. Cold air drying is a better method for drying icefish compared to hot air drying as it improves its rehydration quality.image

The purpose of this study was to comprehensively understand the formation mechanism of nutrient components and flavor compounds during the fermentation process of high-quality highland barley wine (HHBW). The dynamic changes of physicochemical properties, non-volatile compounds and volatile flavor compounds in HHBW at different fermentation times were investigated. The results indicated that the nutrient components and physiologically active substances in HHBW, such as proteins, β-glucan, total phenols and total flavonoids were higher than those in commercial highland barley wine (HBW). In addition, the analysis results of HS-SPME-GC-MS revealed significant differences in flavor compounds at each fermentation stage, with alcohol being the main flavor compound. The contents of aldehydes and ketones decreased rapidly with the progress of fermentation. Lactic acid was the most important organic acid in HHBW. Correlation analysis revealed a negative association between citric acid and most alcohols and esters, while tartaric acid and succinic acid exhibited positive correlations with alcohols. Bitter amino acids, such as valine, isoleucine, leucine, arginine and lysine, were positively correlated with most of the ester flavor compounds. The study can provide a reference for a deep understanding of the mechanism of the formation of the characteristic flavor of HHBW.

Moisture migration is an important factor affecting the performance and durability of laminated veneer lumber (LVL), a common packaging material. In this paper, we used low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) technology to investigate the moisture migration of LVL during water absorption and drying. The results showed that as LVL absorbed water, the signals of both strongly and weakly bound water in the pores increased significantly with time until the samples were fully saturated, and the NMR signals did not change much. The drying process of LVL started with a significant decrease of weakly bound water signals, followed by a gradual decrease of strongly bound water signals until the moisture content in the samples had completely evaporated. MRI was used to observe the water distribution during the water absorption and drying process and found that the visual images were consistent with the quantified NMR spectral results. We also found a linear relationship between the NMR signal and the water mass, and a high correlation between the NMR and weighing results. Our results demonstrated that the combination of LF-NMR relaxation technology and MRI technology is an effective method to analyze the moisture distribution and migration for LVL laminates.

In order to efficiently extract β-glucan from highland barley (HBG) and study its structural characterization and antioxidant activity, ultrasonic–microwave-assisted extraction (UME) was optimized by the response surface method (RSM). Under the optimal extraction conditions of 25.05 mL/g liquid–solid ratio, 20 min ultrasonic time, and 480 W microwave intensity, the DPPH radical scavenging activity of HBG reached 25.67%. Two polysaccharide fractions were purified from HBG, namely HBG-1 and HBG-2. Structural characterization indicated that HBG-1 and HBG-2 had similar functional groups, glycosidic linkages, and linear and complex chain conformation. HBG-1 was mainly composed of glucose (98.97%), while HBG-2 primarily consisted of arabinose (38.23%), galactose (22.01%), and xylose (31.60%). The molecular weight of HBG-1 was much smaller than that of HBG-2. Both HBG-1 and HBG-2 exhibited concentration-dependent antioxidant activity, and HBG-1 was more active. This study provided insights into the efficient extraction of HBG and further investigated the structure and antioxidant activities of purified components HBG-1 and HBG-2. Meanwhile, the results of this study imply that HBG has the potential to be an antioxidant in foods and cosmetics.

Qingke baijiu is a typical light-flavor baijiu and considered as one of the geographical indication products in China. The aroma of newly fermented original Qingke baijiu is unique and popular with consumers. In this work, the key aroma-active compounds of original Qingke baijiu (QKJ) were characterized by combined instrument analysis with sensory analysis. A total of 54 aroma compounds with high flavor dilution factors (FD values >= 9) were screened out by gas chromatography-olfactometry (GC-O) combined with aroma extract dilution analysis (AEDA). After quantitation, 28 aroma-active compounds had odorant activity values (OAVs) > 1 in QKJ. Re-combinant and omission experiments further proved that the esters and alcohols, especially ethyl lactate, phe-nylethyl acetate, ethyl hexanoate, 2-methyl-1-butanol, ethyl acetate, gamma-nonalactone and 2,3-dimethyl-5-ethyl pyrazine were critical to the flavor of QKJ. Consequently, this research reveals the characteristics of QKJ and provides theoretical support for production and quality control assurance.

Abstract The purpose of this study was to investigate the effects of the active ingredients of barley lees on the physiological indexes, intestinal flora, and liver transcriptome of mice fed a high‐fat diet. Twenty‐four male C57BL/6J mice were randomly divided into 4 groups and fed the experimental diets for 5 weeks. The results showed that the fat‐soluble components of distillers' grains significantly reduced body weight, abdominal fat, perirenal fat, blood glucose, low‐density lipoprotein cholesterol, triglycerides, and total cholesterol in the high‐fat diet‐fed mice (p < .05), significantly decreased alanine aminotransferase and malondialdehyde levels, and significantly increased total superoxide dismutase, catalase, reduced glutathione and glutathione peroxidase levels (p < .05). At the phylum level, lipid‐soluble components significantly increased the abundance of Bacteroidetes and decreased the Firmicutes/Bacteroidetes ratio. At the genus level, the relative abundances of Bacteroidetes and Clostridium were increased. Transcriptomic analysis showed that lipid‐soluble components of spent grains reduced the mRNA expression of ANGPTL8, CD36, PLTP, and SOAT1 and increased the mRNA expression of CYP7A1 and ABCA1 in the cholesterol metabolism pathway, promoted the transport of cholesterol, and inhibited the absorption of cholesterol, which can decrease cholesterol levels by speeding up the conversion of cholesterol into bile acids.

Capsular polysaccharide is well known to protect bacteria against various environmental stresses. The gene cluster for CPS biosynthesis is typically organized in the chromosome in bacteria.

Highland barley alcoholic drink (HBD), as one of the most typical rice wines in Qinghai-Tibet plateau area, is generally brewed by adding Jiuqu to highland barley. However, the flavor and quality of HBD fermented with Jiuqu in various plateau regions are different. This study elucidated the potential correlation between the microbial community, physicochemical properties of five traditional plateau Jiuqu, namely Hongxin1 (HX1), Hongxin2 (HX2), Huairang (HR), Hoarfrost gypsophila (HG) and Tibet Qu (TQ), and volatile flavor compounds of HBD. Based on high-throughput sequencing (HTS) technology and LEfSe analysis, it was found that the bacteria and fungi of the five traditional plateau Jiuqu were quite different. Differential microorganisms were Weissella and Pichia in HX1, Lactococcus and Kazachstania in HR, Acetobacter and Rhizopus in TQ. Besides, HX1 and HX2 had higher esterification power, TQ had the highest fermentation power while HR had the lowest enzymatic properties. Finally, RDA and Pearson correlation analysis showed that esterification power and moisture content had positive effects on Lactobacillus, fermentation power and saccharification power were highly positively correlated with Pantoea and Rhizopus, but negatively correlated with Aspergillus. In flavor analysis, Rhizopus, Acetobacter were found positively correlated with alcohols and acids, which contributed to the formation of volatile flavor compounds, Lactobacillus_sanfranciscensis and Lactobacillus_sakei were positively correlated with phenolic compounds. This study showed that the flavor of HBD was seriously affected by the microbiota in Jiuqu, which could help to develop new fortified starter to improve the quality of HBD.

The fat-soluble components of highland barley brewer’s spent grains were extracted via supercritical CO 2 extraction, and the optimal extraction conditions were determined using single factor and response surface experiments. The composition and content of fatty acids and sterols in the fat-soluble components of brewer’s spent grains were analyzed using gas chromatography-mass spectrometry（GC-MS）. The optimal extraction conditions for the fat-soluble components of highland barley brewer’s spent grains were as follows: loading coefficient, 0.6;extraction pressure, 25 MPa; extraction temperature, 40 ℃; and extraction time, 120 min, which led to an extraction rate of 5.50%. According to spectral analysis and peak area normalization method, 18 types of fatty acids were isolated and identified from the fat-soluble components of brewer’s spent grains, mainly linoleic acid, palmitic acid, and oleic acid. The content of unsaturated fatty acids（USFA） was 67.09%, that of monounsaturated fatty acid（MUFA） was 19.66%, and that of polyunsaturated fatty acid（PUFA） was 47.43%. Nine sterols were isolated and identified as fat-soluble components. β-sitosterol accounted for the highest relative content（52.78%）, followed by camphorol（12.80%） and stigmasterol（5.10%）. This study may provide a theoretical basis for the in-depth development and high-value utilization of highland barley brewer’s spent grains.

以陈年青稞酒为酒基,雪菊为呈香呈味物质,采用复蒸馏工艺,经陈酿、过滤、勾调等工序配制得到雪菊青稞酒.酒质无色,澄清透明,有光泽,入口雪菊清凉芳香,酒香花香协调,味道怡人,口感舒畅丰满,醇厚爽口,雪菊香味绵长,富含丰富的氨基酸、黄酮类、萜烯类化合物,独特的香气和口感深受消费者的喜爱.

The traditional natural Jiuqu for brewing hulless barley wine contains a variety of complex microorganisms and enzymes. The uncertainty of microbial composition in Jiuqu and the existence of some miscellaneous microor-ganisms are not conducive to the production of high-quality hulless barley wine. In order to improve the flavor quality of hulless barley wine, the mixed starter was designed to reconstruct the fermentation microbial flora. Mold strains with high saccharification ability and yeast strains with good fermentation performance were screened from the traditional natural Jiuqu for brewing hulless barley wine and were identified. And then, mixed starters by molds and yeasts were used to ferment hulless barley wines on a laboratory scale. The physico-chemical indexes, sensory evaluation, volatile flavor compounds and electronic nose (E-nose) analysis of hulless barley wine brewed by different combinations of mold and yeast were analyzed. The hulless barley wine (W4 wine) brewed by the mixed starter Q4, which combined by Rhizopus oryzae, Saccharomyces cerevisiae and Wickerhamomyces anomalus, had the best volatile flavor and sensory score. This improvement was mainly re-flected in the higher content of esters (252.62 +/- 0.02 mg/L) and alcohols (72.77 +/- 2.03 mg/L), with esters accounting for 67.37 % of the volatile flavor compounds. In addition, the sensory score of "bitter" was the lowest in W4 wine while the scores of "sweet", "wine-aroma" and "fruit-aroma" were the highest. These results demonstrated that the mixed starter Q4 could effectively improve the flavor of hulless barley wine.

The aim of this study was to identify antioxidant peptides from highland barley distiller's grains and evaluate their antioxidant activity in vitro. The results showed that the enzymatic hydrolysate of highland barley distiller's grains prepared by ultrasonic assisted alkaline protease had antioxidant properties, aromatic amino acids accounted for 61.48% of the total free amino acids and acidic/basic amino acids accounted for 40.82% of the total hydrolyzed amino acids in enzymatic hydrolysate. Ultrafiltration component F1 (Mw < 1 kDa) had the highest DPPH, ABTS and hydroxyl radical scavenging activity and ferrous ion chelating activity, which were 93.92%, 69.59%, 50.27% and 0.71, respectively. Four peptides were identified and screened by LC-MS/MS and the P1 (SWDNFFR) and P4 (WDWVGGR) showed high scavenging ability of DPPH free radical (70.23%-62.84%) and ABTS free radical (30.87%-60.54%). Molecular docking showed that P1 and P4 formed multiple hydrogen bonds with central residues of MPO.

Qingke (highland barley) Baijiu is a special Chinese Baijiu which is mainly produced from Qinghai-Tibet Plateau. Since the pine board is used as the bottom of the fermentation pit, we deduced that the terpenoids and norisoprenoids in pine board might be introduced into Qingke Baijiu. Thus, the terpenoids and norisoprenoids in Qingke Baijiu were investigated by headspace solid phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-TOFMS). The results showed that γ-terpinene (0.70–530.72 μg/L), α-phellandrene (0.34–256.66 μg/L), longicyclene (0–38.55 μg/L), α-pinene (1.21–35.54 μg/L) and limonene (0.93–23.69 μg/L) were the top 5 terpenoids/norisoprenoids in Qingke Baijiu. Pulegone was detected and reported for the first time in Baijiu, and the concentrations in Qingke Baijiu were 0.78 μg/L (fresh) and 3.90 μg/L (7 years old). According to the principal component analysis (PCA) plot, young, aged, and retail Qingke Baijiu could be differentiated clearly. Fold change (FC) and t-tests analysis indicated that β-pinene, γ-terpinene, and α-selinene were the most different terpenoids/norisoprenoids between young and aged Qingke Baijiu, and longifolene was the most different terpenoids/norisoprenoids between base and retail Qingke Baijiu. The terpenoids and norisoprenoids, such as (E)-β-ionone, isoborneol and β-cyclocitral, could be potential markers indicating the ageing process of Qingke Baijiu.