Later, people gradually found that the taste of wine, the length of brewing time, and even the success of brewing are all related to raw materials. Usually, grain will be moldy or germinated after being wet, and only moldy or germinated grain can become wine. So people make these moldy or germinated grains into the most primitive distiller's yeast, which is also the raw material for fermentation. With the general development of brewing technology, koji has become the secret of brewing quality, but ancient people did not know exactly how koji worked. In ancient times, some philosophers speculated on the existence of microorganisms. For example, the Buddhist scriptures say that "a pot of water is worth 84 thousand worms." In the wine-making works of the Song Dynasty in China, it has been clearly recorded that the floating objects on the surface of the liquid in the fermentation tank are skimmed by strong fermentation, which is called "yeast". After air drying, it can be made into "dry yeast", which can be preserved for a long time. In ancient times, most people didn't know the existence of microbial life, let alone know and understand microorganisms. However, the brewing and fermentation process dominated by these microorganisms continues without knowing anything about microorganisms. According to the inspiration and experience gained by chance in the practice of production and life, people have produced jade liquid and nectar. This situation of "knowing it but not knowing why" has continued until modern times. Modern science finally solved the mystery.
/kloc-in the second half of the 0/7th century, the microscope was invented, and people gradually realized the existence of microorganisms. By the middle of19th century, the famous French biologist Pasteur (1822- 1895) discovered through experiments that alcohol fermentation was originally caused by living yeast, thus revealing the relationship between microorganisms and fermentation. Later, it was found that the so-called "distiller's yeast" was added in the brewing process because a large number of microorganisms (such as yeast) grew on distiller's yeast, and the enzymes secreted by these microorganisms (such as amylase, glucoamylase and protease) had biocatalysis and could accelerate the conversion of starch and protein in grains into sugar and amino acids. Sugar is decomposed into ethanol under the action of yeast enzyme, which is alcohol. In ancient times, tillers used to make wine also contained many such enzymes, which had saccharifying effect. The starch of tiller itself can be converted into sugar, and then converted into ethanol under the action of yeast. At the same time, koji itself contains starch and protein, which are also raw materials for brewing.
Yeast is the soul of brewing all kinds of wine. Every world-famous wine in the world uses excellent yeast. For example, in Japan, Asahi Beer uses different yeasts for every wine produced. Asahi Beer Central Research Institute even has a "yeast bank" to store 500 yeasts needed for beer production. For example, Asahi draft beer, which is located in mellow and refreshing taste, comes from the code name "No.508 yeast" and is located in super cool beer, which is selected from "No.365438+No.08 yeast".
China's famous Tsingtao beer also uses pure German yeast. Here is another little-known story.
1903, the Germans occupied Jiaodong Peninsula and established a brewery in Qingdao. At that time, German managers brewed Tsingtao beer in strict accordance with the German brewing method-using high-quality malt and famous Bavarian hops, using pure yeast, without adding any auxiliary materials. But those Germans never imagined that these little yeasts would be passed down in China for more than a century and write legendary poems for the beer industry in China and even the world.
In the following period, after more than ten years' efforts, several generations of managers made the yeast brewing Tsingtao beer more stable and well continued the German flavor. Although historical records show that Tsingtao Brewery has made some modifications to the factory and technology, it has never been replaced in the use of yeast.
In the mid-1940s, the bumpy Tsingtao beer yeast was taken over by the Kuomintang government, and the production of Tsingtao beer was not completely delayed. At that time, in order to improve the quality of Tsingtao beer, managers specially invited some excellent technicians from China and Taiwan Province Province to join in and conduct special technical research. After some efforts, the performance of yeast has been effectively preserved and improved, which laid the foundation for the rapid development of Tsingtao beer in the future, including Zhu Mei, a famous beer expert in China.
In the process of the withdrawal of Kuomintang troops, there was actually an unforgettable history, and Tsingtao beer yeast was almost destroyed by human beings. Wu Gengyong, an 84-year-old former chief engineer of Tsingtao Brewery, a famous brewer in China and a technical expert with outstanding contributions in the beer industry, recalled that when the Kuomintang troops stationed in Qingdao retreated, they sent people to Tsingtao Brewery many times to try to destroy the factory building and process equipment. It is said that explosives were buried under the main building and the fence of Tsingtao Brewery. Out of a sense of responsibility for Tsingtao Brewery, and in order to leave some yeast as the spark of China beer industry inheritance, Tsingtao Brewery employees spontaneously organized to protect Tsingtao Brewery's century-old yeast with courage and justice. Thanks to the efforts of many upright Tsingtao Brewers, the yeast has not been destroyed.
With the birth of New China, Tsingtao Brewery Yeast finally ushered in a new bright journey. Tsingtao Brewers, who regard yeast as their life, finally got back the "custody right" of yeast for a hundred years. In order to better protect and improve the purity and brewing characteristics of yeast, Tsingtao Brewery entrusted a professional organization with international technical level to preserve yeast, and spared no expense to establish a fully functional yeast seed bank and scientific research center.
Yeast plays an important role in the process of wine brewing and is also used in the large-scale production of alcohol industry. Especially in today's energy crisis and serious pollution, the contribution of yeast can be described as "infinite". At present, all countries in the world encourage the development of clean energy fuel ethanol instead of oil, while in China, we mainly support the production of fuel ethanol from non-grain raw materials such as potatoes, sweet sorghum and fiber resources. It is estimated that by 2020, the biofuel consumption in China will account for about 15% of all transportation fuels. Yeast is an irreplaceable starter in the production of fuel ethanol, and its role is very critical. The high-temperature resistant super wine yeast developed and cultivated by Angel Yeast Co., Ltd. has increased the wine production by 15%, which is a miracle in the world fermentation industry, and the project has also won a national patent.