How to apply jiuqu (rice wine starter) in orchid care

Today, after reading orchid-growing friend Wan Yunkun's article "On the Application of 'Jiuqu' inorchidcultivation", since the brewing industry happens to be one of the projects in my own profession, I have some knowledge of it and have also used "jiuqu" and "jiuba" (distiller's grains) asorchidgrowing test media. In order to let the broad community of orchid growers understand more clearly the application of "jiuqu" inorchidcultivation, and to avoid half-understood guidance causingorchidsirreparable fungal damage, I have written this modest article to explain, and I respectfully ask all the experts and seniors to kindly correct me. "Jiuqu", also known as "baike", "jiuyao", "jiumu", contains "saccharifying bacteria" and "yeast", looks like a ping-pong ball (there is also a powdered form), is white, and crumbles when lightly pinched. It can convert starch into alcohol. In an era when the microbial industry was undeveloped, "jiuqu" was an indispensable material for brewing wine. The rough method by which ordinary folk make jiuqu is to take raw flour (rice, wheat, beans, rice bran...) and add water or herbal juice, stir it, press it into a mold and tamp it firm, then leave it to grow mold and ferment (during this period attention must be paid to regulating temperature and humidity); after three months, turn it over and stack it, and it becomes jiuqu. The making of jiuqu must use controlled conditions to screen high-quality yeast and qu fungi from the natural environment, but almost all of the raw material used is unsterilized raw material, and the air in the qu room also circulates with the outside, so in the process of making jiuqu not only yeast and qu fungi are produced, but also some acid-tolerant and anaerobic contaminating bacteria are mixed in, such as esterifying bacteria, lactic acid bacteria... Because of these contaminating bacteria in jiuqu, they also cause abnormal changes in the flavor of the brewed wine. As for whether the wine's flavor becomes better or worse, or even turns sour, it all depends on the quality of the jiuqu, and the quality of the jiuqu in turn depends on the conditions under which the jiuqu is made. So to make good jiuqu truly requires favorable timing, location, and human cooperation. For this reason, the jiuqu for our country's famous liquors is always made in-house, and the qu room is never easily changed; if it must be moved, some implements must be moved over from the old qu room, and qu makers are also passed down from generation to generation. From the standpoint of professional winemaking conditions, with so many variable conditions existing, it is very difficult to control quality. After the above explanation of "jiuqu", I believe everyone has a basic concept. Now let me get to the point and introduce the application of "jiuqu" in orchidcultivation. Before the development of "active soil", I had also used "jiuqu" and "jiuba" as additive media for growingorchidplants. In media of granular soil, Zhijinshi, longan bark and tree-fern sawdust, I added a little "jiuqu" and "jiuba", and after several comparative trials with several groups of different orchid varieties, I found that when the temperature was below 20°C, the relative humidity was below 40%, and the potting medium in the orchid pot was relatively dry, there seemed to be no effect on the orchids; at temperatures of 20-25°C, relative humidity of 50-60%, and the potting medium in the orchid pot relatively dry, one could feel that the orchids indeed showed obvious effects in development; but when the temperature was above 25°C and the relative humidity was 60-80% or above, the surface of the potting medium began to grow thread-like white fuzz similar to southern blight, and afterward the orchids gradually showed symptoms of damage: first the leaf sheaths and leaves turned yellow, then the pseudobulbs turned black, producing symptoms likesoft rotdisease. After emptying the pot to inspect, I found the orchid pot filled with thread-like white fuzz, and the orchid roots blackened with water-soaked swelling. Later, upon asking some qu-making experts, I learned that jiuqu contains two kinds of fungi, mold and yeast. In the brewing process of winemaking, the growth of mold produces liquefying and saccharifying enzymes, and such liquefying and saccharifying enzymes can make yeast proliferate into a dominant strain. However, when mold grows and produces liquefying and saccharifying enzymes, it generates heat. When the generated heat cannot be effectively removed, it continuously accumulates and raises the temperature, and ultimately instead kills itself and the yeast present in the jiuqu! This situation is called "qu burn" in winemaking technology. When water is added, the contaminating bacteria from the water or the atmosphere instead become the dominant strain. This situation is especially likely to occur in summer, because the ambient temperature around is high in summer, and qu heat is even harder to remove, making the probability of qu burn higher. Therefore, under high-temperature and high-humidity conditions, orchids developing conditions similar to southern blight andsoft rotdisease should be regarded as a phenomenon of "qu burn", that is, the contaminating bacteria in the "jiuqu" and "jiuba" in the medium produce liquefaction and saccharification, and the high heat generated kills the orchid fungi in the medium and on the orchid roots. After the temperature cools down, because the mold and contaminating bacteria of the jiuqu in the orchid pot greatly outnumber the beneficial nitrifying bacteria and orchid fungi, under the law of the jungle where strains suppress one another, the orchids suffer fungal damage leading to the occurrence of southern blight andsoft rotdisease. Therefore, I must appeal to everyone here: "jiuqu" is not suitable as an additive to the medium when growingorchidplants. However, "jiuba" after full fermentation can be used as a top dressing, but before use it is best to undergo a sterilization procedure to completely kill the "jiuqu" remaining in the jiuba before using it. Finally, I must emphasize one point: "active soil" is not equal to "jiuqu". "Active soil" is only used as an additive material when growing orchids; it itself contains no strains of any kind. It is merely a natural organic plant material. Simply put, it is the best nutritional material for culturing orchid fungi. Regarding the application of "active soil" inorchidgrowing, as long as everyone does not mind the suspicion of promotion and advertising, in the future Amiao will very gladly present his own experience and results for everyone to discuss together. Thank you, everyone!! (Taiwan, China, Guo Jianmiao)