Some studies have continuously tested fermented baiyunbian baijiu, and the results show that the bacterial community is dominated by Bacillus, and Lactobacillus; the most common fungi are Paecilomyces spp., yeast, and Zygomycetes cerevisiae. A large number of fungi were from the genera Thermomyces, Aspergillus, Monascus, and the subgenus Isachenki, as well as some prokaryotes belonging to the genera Acetobacter, Lactobacillus, and Thermoactinomycetes. Analysis by GC-MS showed that the distiller’s grains contained high concentrations of ethyl lactate, 2,3-butanediol, and ethyl caproate, which were mainly produced by the co-fermentation of Lactobacillus and yeast ( Liu and Miao, 2020). Dong et al. (2022) found that the dominant bacteria ( Weissella and Leuconostoc) were replaced by Acetobacter and Gluconobacter, and the dominant fungus ( Rhizopus) was partially replaced by Thermomyces in the saccharification stage of Baijiu brewing. While, in the fermentation stage, the dominant bacteria were replaced by lactic acid bacteria, and the dominant fungus was completely replaced by Thermoascus and other three yeasts, including Saccharomyces, Kazachstania, and Apiotrichum. The formation of flavor substances (acetic acid, lactic acid, hexanoic acid, ethyl lactate, and ethyl lactate) was found to be closely related to Kazachstania and Apiotrichum. Feng-Flavored Baijiu Roughly ten years have elapsed since comprehensive GC × GC/TOF-MS was first applied for the chemical analysis of alcoholic drinks 16, specifically for amino acid and methoxypyrazines analysis in wines and beers 6, 16. In 2007, a similar approach was used to study samples of a Chinese liquor (Moutai) extracted by LLE leading to the identification of 528 compounds 5 and demonstrating the power of this technique (viz. GC × GC/TOF-MS coupled to LLE) for chemical analysis. In this study, SPME and LLE were combined for enhanced extraction and a more complete characterization of the compounds in Chinese liquors. Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering and Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, China We’ve made no secret that China and the region are a major priority for the Australian Open, and that we take our role as the Grand Slam of Asia-Pacific seriously. Luzhou Laojiao Co.,Ltd Announces 2022 Final Profit Distribution Plan to Be Implemented (A Shares), Payable on 28 August 2023

Strobel, G. A., Dirkse, E., Sears, J. & Markworth, C. Volatile antimicrobials from Muscodor albus, a novel endophytic fungus. Microbiology 147, 2943–2950 (2001). The People's Liberation Army took control of Luzhou on December 6, 1949, from the Kuomintang government, two months after the founding of the People's Republic of China. In 1960, Luzhou prefecture was created with five counties that had been part of Yibin prefecture. The prefecture was upgraded to the prefecture-level city of Luzhou in 1983. Nowadays, Luzhou is considered a center of the chemical, machinery, and liquor-distilling industries. Lady Cooper. "Review: Luzhou Laojiao Liquor". Liquor Log. Archived from the original on 13 July 2007. Luzhou is a center of liquor production, particularly baijiu. Luzhou Laojiao ( Chinese: 泸州老窖; lit.'Luzhou Old Fermentation Pit') and Gulin Langjiu ( Chinese: 古蔺郎酒) are the two best known brands with national and international reputation. Over 200 liquor products are listed as national and provincial products with good market share in China and abroad. Luzhou is served by a freight-only branch. A passenger service briefly operated but was cancelled in 1995. [7] A new railway station served by multiple high-speed lines has opened on June 28, 2021, with links to Chengdu and various other cities. [ citation needed] Luzhou Port [ edit ]Today Luzhou Laojiao is ranked as the fourth most valuable spirits brand internationally. [4] History [ edit ] The Australian Open has landed a significant partnership deal with leading Chinese Baijiu brand Luzhou Laojiao in the largest Chinese sponsorship deal in the history of the tournament. Luzhou Laojiao is a complex, premium baijiu of the "strong aroma" ( nóngxiāng) class. [12] It is a strongly alcoholic (more than 50% alcohol), clear liquid with a sharp aroma of fermented peaches. [13] It is fermented in old cellars (fermentation pits), whose walls are coated with a unique clay composition that gives the spirit its aroma and palate. [12] Shen, Y. Manual of Chinese Liquor Manufactures Technology (Light Industry Publishing House of China, Beijing, 1996).

It is notable that over 1,300 compounds were detected for each type of the Luzhoulaojiao liquor investigated here and that most of these are also found in other Chinese liquors. Moreover, many of these compounds are detected here in Chinese liquors for the first time. The volatiles in different Luzhoulaojiao liquors have been studied previously. For example, in 2014, 31 compounds were detected in 12 liquors from Luzhou Co., Ltd. by GC-MS 18. Moreover, Guojiao1573, a type of Luzhoulaojiao liquor was extracted by SPME, within which 86 compounds were detected 19. Many more compounds were detected in Luzhoulaojiao liquors in the present study, demonstrating the value of GC × GC/TOF-MS analysis coupled to LLE and SPME in this context. In a previous study reported in 2007, 528 compounds were detected in Moutai liquor. Here, more than 1,800 compounds were detected in the same liquor, demonstrating the gain in efficiency afforded by the method developed herein. It is reasonable to suggest that the approach put forward in this study will be integral to decomposing the complex compound matrix of Chinese liquor. Baizitu is situated near the Tuojiang river, in the northwestern corner of Luzhou city. It is named for the stone inscription of the Qing Dynasty and was the protected historic and cultural relic of Luzhou. Xu, G., Ye, F., Kong, H., Lu, X. & Zhao, X. Technique and advance of comprehensive two-dimensional gas chromatography. Chin. J. Chromatogr. 19, 132–136 (2001). Zhang, C., Wang, S., Zuo, P., Cui, X. & Cai, J. Effect of tetramethylpyrazine on learning, memory and cholinergic system in d-galactose-lesioned mice. Acta Acad. Med. Sin. 25, 553 (2003). In Ming Dynasty (1368 - 1644 AD), the mud cellars were built and the brewing method was improved. At that stage, as the Daqu yeast had been invented and adopted to make wine, Luzhou Laojiao was officially formed and developed stronger. By the establishment of People’s Republic of China, especially after 1978, modern technologies are applied in producing process, the liquor brand welcomes a new age.The four main steps in the production of Maotai-flavored baijiu are jiuqu making, alcoholic fermentation, solid-state distillation, and aging. In Maotai-flavored baijiu, sorghum (as a raw starch) and a unique Daqu (high-temperature Daqu) are mixed and fermented naturally in an open environment. Two-stage alcohol fermentation (including heap fermentation and cellar fermentation) occurs without directly or indirectly adding edible alcohol or non-self-fermented color, aroma, or taste substances ( Jin et al., 2017; Liu and Miao, 2020). Maotai and Langjiu, are the most representative baijiu of Maotai-flavored baijiu, which provide a soy sauce-like aroma, full taste, and long-lasting aroma. To date, 528 compounds have been identified from Maotai-flavored baijiu ( Zhu et al., 2007; Liang et al., 2019). Although over 30 major flavor substances have been identified in Maotai-flavored baijiu, the main aroma components remain inconclusive. Studies have shown that aromatic compounds (phenolic compounds) are its representative flavor, mainly tetramethylpyrazine and syringic acid, and a small number of amino acids, organic acids, and esters ( Xiong, 2005). The contents of organic acids (acetic acid and lactic acid), aldehydes, ketones, alcohols, amino compounds, and nitrogen compounds in Maotai-flavor baijiu are high, while the total ester content is low. It is worth noting that the content of pyrazine and furan is also much higher than other baijiu ( Wang et al., 2019). Currently, the chemical analysis of liquor components is performed by gas chromatography-olfactometry, or by gas chromatography coupled to mass spectrometry after sample extraction 4. However, distinguishing the compounds in a complex matrix such as Chinese liquor proves difficult when using traditional one-dimensional gas chromatography, even with highly efficient columns and temperature gradients 5. For the chemical analysis of complex mixtures, advanced chromatography—such as comprehensive two-dimensional gas chromatography (GC × GC) coupled with time of flight mass spectrometry (TOF-MS)—is the preferred approach 6. Moreover, the effectiveness of GC × GC is broadly accepted for the detection of volatile compounds, which are the dominating trace composition in Chinese liquor 1, 7. The international standard databases (MAINLIB and REPLIB) facilitate detection and qualification, due to the use of electron impact ionization (EI), which produces repeatable and interpretable spectra 8, 9, 10. However, reports on the application of GC × GC for the chemical analysis of Chinese liquors are few in the literature 5, 11, 12 and this technique was first applied on a Chinese liquor (Moutai) in 2007 only 5. However, the performance of the applied method (GC × GC/TOF-MS coupled to liquid-liquid extraction (LLE)) was limited by the capacity of LLE, whereby only 528 of the compounds in Moutai were extracted. Improving the chemical analysis needs to improve the associated sample extraction methods. Common among these are LLE, solid phase extraction, solid-phase microextraction (SPME) and stir bar sorptive extraction 13. Liquid-liquid extraction using organic solvents has been shown to be a suitable method for the concentration of target compounds in Chinese liquor, readily extracting most of the volatile compounds 5. Solid-phase microextraction is based on the adsorption of SPME fibres 14 and is complementary to LLE. As well as being a solvent-free approach, it offers reproducibility, sensitivity and selectivity 2. The extraction biases of LLE and SPME are different, leading to the identification of different sets of compounds. In a previous study of distilled liquors indeed, LLE was found to extract a greater number of higher alcohols, while SPME was to be more sensitive to esters and acids 15. Using both methods in combination may increase the number of compounds that can be identified and compared.

To the best of our knowledge, Luzhoulaojiao liquors have not been submitted to date to a comprehensive chemical compound screening. This was performed here using TOF-MS spectral databases including MAINLIB and REPLIB. The signal to noise criterion was adjusted to “≥50” to include most of the peaks and the identification acceptance criterion was set as “similarity > 600”. This led to the identification of more than 1,300 compounds in each type of Luzhoulaojiao liquor. Luzhoulaojiao liquor L17 was found to be the richest by this measure, with about 2,400 compounds detected. Common compounds in 18 types of Luzhoulaojiao liquor Adahchour, M., Beens, J. & Brinkman, U. Recent developments in the application of comprehensive two-dimensional gas chromatography. J. Chromatogr. A 1186, 67–108 (2008). The alcoholic fermentation of light-flavored baijiu, also known as light-flavored baijiu, is conducted in clay tanks, unlike Maotai-flavored baijiu and Luzhou-flavored baijiu, which are carried out in mud cellars. Light- flavored baijiu utilizes sorghum and wheat as the raw material and is brewed by steaming twice with slag cleaning technology. The production process of light-flavored baijiu involves a solid, open, natural fermentation, and therefore, the fermentation microorganisms of the light-flavored baijiu not only are derived from jiuqu but also derived from the surrounding environment. The most representative product of light-flavored baijiu is Fenjiu, and there is also Erguotou baijiu, with its mellow sweetness and fresh aftertaste. In many studies, it was determined that most flavor substances in light-flavored baijiu were synthesized at the late fermentation stage, and its metabolites were esters, alcohols, alkenes, sulfides, and ketones, furans, aldehydes, nitrogen compounds, alkanes and so on. The aromatic compound ethyl acetate is one of the main characteristic aromatic substances, which is balanced with a considerable amount of ethyl lactate. The proportion of n-propanol and isobutanol in alcohols was higher, which had a great influence on the flavor characteristics of baijiu ( Liu and Miao, 2020). In addition, acetic acid and lactic acid are the main acids, with concentrations of 1 and 0.28 g/L, respectively, accounting for about 98% of the total acid content ( Fan et al., 2018; Wei et al., 2020). Moreover, the ester acid ratio of light-flavored baijiu was higher than that of Luzhou-flavored baijiu ( Yu et al., 2014).

Formation of Flavor Substances in Baijiu

Castro, R., Natera, R., Benitez, P. & Barroso, C. G. Comparative analysis of volatile compounds of ‘fino’ sherry wine by rotatory and continuous liquid-liquid extraction and solid-phase microextraction in conjunction with gas chromatography-mass spectrometry. Anal. Chim. Acta 513, 141–150 (2004). Pawson, Helen (1 May 2018). "Chinese liquor company Luzhou Laojiao eyes global travel retail expansion". The Moodie Davitt Report . Retrieved 20 January 2019. Owing to its position in the southern peripheral area of Sichuan Basin and the connective region with Yunnan and Guizhou plateau, Luzhou is characterised by the river valleys, hills, and level lands in the north and highland, mountains, sheer valleys and rushing rivers in the south. Fishing and agriculture are the primary industries in the northern area and forest and mineral resources to the southern region respectively. The lowest part is 203 metres (666ft), at the surface of Yangtze river in Jiucengyan, Hejiang county while the highest point is located at the peak of Liangzi mountain, Xuyong County, reaching 1,902 metres (6,240ft). Luzhou is also a region covered by rivers. The Yangtze river flows through the whole area from west to east, covering a total course of 133 kilometres (83mi), and the maximum flood level was 18.68 metres (61.3ft) during the past 30 years. Other rivers converging here, such as Tuo River, Yongling River, Chishui River, and Laixi Rivers. Luzhoulaojiao liquor is historically one of the most famous Chinese liquors whose fame has spread worldwide since its award of the gold medal at the Panama-Pacific International Exposition of 1915 in San Francisco 3. Furthermore, Luzhoulaojiao liquor has enjoyed a lofty reputation in China since it was named among the four most famous Chinese liquors at the first Liquor Tasting Conference in 1952 in Beijing (the three others being Xifeng, Fen and Moutai). Like other Chinese liquors, Luzhoulaojiao liquor consists of a complex mixture of compounds with a wide range of different physicochemical properties 1, which may contribute to the flavor and bioactivity of the liquor. The identification of these components is therefore an important step in understanding and improving the distillates. The Song Dynasty was an important period in Luzhou's history. It was known as the natural granary of southern Sichuan as the liquor-distilling and salt-refining industries expanded. The method to decoct salt with natural gas was discovered at that time, according to ancient literature. In addition, trade and business between Luzhou residents and ethnic groups was brisk and a protective wall as well as forts were constructed by the local government.