Jiuzhu Dumplings, also known as "mash", is a Chinese snack with a sweet, alcoholic flavor that is popular in Shaanxi, Sichuan, Jiangsu, Zhejiang, and Beijing. Mash is made from glutinous rice (also known as river rice in northern China) rice fermented with liquor medicine (made from rice and edible fungi). Mash has a long history, and the Shuo Wen Jie Zi (Explanation of Chinese Characters) says: "In ancient times, Yi Di made wine and mash, and when Yu tasted it and it was beautiful, he spared Yi Di." In this case, "wine and mash" may be a food similar to mash.
Method of preparation
1. Wash the glutinous rice, add three bowls of water to two bowls of rice, and cook it in the usual way. It is also said to soak the glutinous rice for 3-6 hours and then put it in a steamer to steam. You can also use regular rice.
2. Grind a small piece of liquor medicine into a fine powder. It is also said to melt the liquor medicine in water.
3. When the glutinous rice has cooled down to below 40 degrees Celsius, serve it in a container (you can also leave it in the pot) without leaving too much empty space, but it should not be compacted either. One or several shallow pits can be dug on the surface.
4. Sprinkle the powder or solution of liquor medicine evenly on the surface of glutinous rice. It is also said that the powder or solution of liquor medicine is evenly mixed inside the rice. Cover the container tightly, e.g. you can cover it tightly with plastic wrap (but leave a small amount of air.)
5. Keep warm 35-37 ℃, depending on the depth of the container, a day and a half to two days to eat. If there is no insulation conditions, room temperature about four or five days can also complete fermentation. Too high a temperature will affect the propagation of edible bacteria.
6. The finished mash should be eaten as soon as possible or put in the refrigerator, otherwise the over-fermentation will make the rice grains empty and the flavor of the wine too heavy and affect the flavor.
Sake medicine
Made into cubes, sake medicine, also known as sake mother or koji, contains a large number of microorganisms, including bacteria and fungi, and is used to ferment a wide variety of foods. The raw materials, production methods and microbial composition of koji vary from one use to another.
The sake koji for mash is made from indica rice and is mostly made into cubes, which are white in color. The main active ingredients are two types of fungi - root molds and yeast.
Fermentation process
The main component of glutinous rice is starch (a type of polysaccharide), especially branched-chain starch. When the koji is spread, first the root molds and yeast begin to multiply and secrete amylase, which hydrolyzes the starch into glucose. This is where the sweetness of the mash comes from. The white mold on the surface of the mash is the mycelium of the root mold. Subsequently, glucose glycolysis occurs in the fungal cells under anaerobic conditions, breaking down glucose into alcohol and carbon dioxide:
C6H12O6 → 2 C2H5OH + 2 CO2
However, glucose can also be oxidized completely to carbon dioxide and water under aerobic conditions, providing more energy:
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O
Already produced alcohol can also be oxidized to acetic acid:
2 C2H5OH + O2 → CH3COOH + H2O
Therefore, a small amount of air can be retained at the beginning of the fermentation process in order to allow the edible fungi to multiply rapidly using the large amount of energy provided by aerobic respiration to speed up the fermentation. However, once the fungus has proliferated, more oxygen should be prevented from entering so that the glucose is oxidized to carbon dioxide for nothing or the mash turns sour.
In summary, the fermentation time needs to be controlled more accurately, just right: too long, the starch is broken down, the wine flavor is too big, like a drink, no chewy; not enough time, the rice is not yet crispy, sticky taste, like glutinous rice. It is also best not to open it during the fermentation process, as oxygen will enter on one hand, and may cause contamination by stray bacteria on the other.
Direct consumption
Jiu mao can be consumed directly, especially in Beijing, where this method is predominant. Since there is already a lot of sugar in the mash itself, it is never necessary to add more sugar when using it. A common method is to add a little cinnamon for flavor. Or add diced fruit for a nice flavor. However, in southern China, many people consider this to be too sweet or too alcoholic to eat directly, and need to process and dilute it before serving.
Moromi dumplings
Moromi dumplings (also known as wine dumplings, wine dumplings, wine dumplings) are widely popular in China's Yangtze River Basin, such as Sichuan, Hunan, Jiangsu, Zhejiang and other places, as well as in Taiwan. To make the dumplings, first boil the mash in water, add the dumplings (usually small dumplings without filling), and wait until the dumplings float, then they are cooked, and a small amount of cinnamon can be added. Mash dumplings are fragrant and refreshing, with a wine flavor but not too strong. It is also common to crack an egg flower into the water as it boils. Another school of thought is to wait until the dumplings are cooked, and then add the wine before and after the fire is turned off. It is believed that excessive heating affects its nutritional value, and that wine is a fermented food, and when it is cooked for a long time, the strains of bacteria are destroyed by the high temperature, which makes it easy to lose the flavor and leads to a bad taste. The more you do, the more you cook the dumplings and the more you cook the wine, the more you want the soup to be clear.
Other
Add fresh mash juice to milk and leave it at room temperature overnight, and the milk will solidify. This is another way to make Beijing snack cheese (the usual way is to add agar to the milk and let it cool). This cheese is sweeter and has a slightly wine-like flavor.