Chapter 2.3 Jiuqu-making Technology

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2.3.1 Wheat Jiuqu Traditional wheat Jiuqu production

As mentioned, 8 varieties of Jiuqu which are made by wheat flour and the other is made by millet flour. As the prepartion methods and conditions were different, the hydrolytic activity of these Jiuqu varied greatly. The most powerful Jiuqu was "Shen Qu". Only a small amount ( about 3% of the raw material for brewing ) of "Shen Qu" was need to make rice wine. The flow chart for preparation of "Shen Qu" discribed in << Qiming Yaoshu>> is shown in Fig. 1.

     Fresh water      Roasted wheat    Uncooked wheat    Steamed wheat
         │                ↓            ↓                    ↓
         │              Milling        Milling             Milling
         │                │            │                    │
                        all ingredients are mixed  thorougly
                         transfered to incubation rooms
                         spread the Jiuqu onto the ground
                                   │ the  microorganisms  multiply  and
                                   ↓ penetrate into the inside of Jiuqu block
                         turn over the Jiuqu
                         stack of the Jiuqu
                         seal the Jiuqu in the jar or vats
                    Jiuqu ready for rice wine brewing
It was noticed in ancient times that the control of temperature and moisture during the development of Jiuqu is important to the preparation of good Jiuqu. We could not know exactly what temperature was controlled in ancient times, but the temperature pattern during the period of Jiuqu-making was obviously well understood by ancient people. People checked the Jiuqu temperature at the first several days regularly. When the temperature rose rapidly, the windows were opened, straw covers were removed. When room temperature below normal conditions, the Jiuqu were heaped together. A rather high moisture content is required at the begining of the approximate 3- day incubation period when mycelial growth occurs followed by a lower moisture content in later stages when spores are being formed. The incubation period usually was 7 weeks to promote adequate production and accumulation of enzymes.Matured koij is clear yellow to yellowish -green in color.
The preparation process of Ben qu is similar to that of Shen qu, but the main differences is that the all the raw material──wheat ── is roasted, and the dimension of the Jiuqu is bigger than Shen qu.
It was described by <> that the mixed materials for Jiuqu making are shaped with round or spuare frames, instead of hands. This makes the sizes and thickness of the Jiuqu evenly, and the quality of the Jiuqu was guaranteed.
Wheat Jiuqu-making techniques in ancient times developed slowly. They could be subdivided into several forms:
Straw-weapped wheat Jiuqu: the Jiuqu is wrapped in straw, allowed to be incubated for a month, and then sun-dried.
Hanged over wheat Jiuqu: To prepare "Hanged over wheat Jiuqu", wheat is mashed, mixed with suitable amounts of water, and shaped into retangular parallelepiped, roughly wrapped in rice straw, and hung under the rafters until each block is covered with a white bloom of natural mold and be dried by wind. Pure cultured wheat Jiuqu

After the founding of the People's Republic of China, scientists have isolated a number of microorganisms from traditional Jiuqu. Aspergillus spp. are used widely. Pure culture or mixed culture of molds became a popular operating procedure. The raw materials may be sterilized by steaming, and this wheat Jiuqu is called "cooked wheat Jiuqu"; The raw materials may also be subjected no heat treatment, and this is called " uncooked wheat Jiuqu".
There are three forms wheat Jiuqu prepared by the pure culture method.
(1) Incubation on ground in incubation rooms
The flowchart of this wheat Jiuqu is given below.

     wheat →crush to croase grists→adding water, and mixing →steaming

→cooling→innoculation with mold spores→heap→spreading on ground →

1st turning over→2ed truning over→finished wheat Jiuqu
(2) Incubation in the through-flow system
The equipment for wheat Jiuqu preparation is like the germinating compartments used in malting. The wheat grists are innoculated with pure cultured mold spores, then heaped up for 3 hours. The materials are spreaded onto the perforated plate mounted at the bottom of the compartment with the wheat grist bed thickness of 30 cm. The aerobic filamentous fungi are cultured by passing temperature- and moisture -controlled air through the wheat grist bed. Heat removal from large -scale operation is no longer a major problem, as it can be facilitated by increasing the aeration rate or the frequency of aeration for systems that are not continuosly aerated.
(3) Incubation in tray
The uncooked wheat grists are mixed with water and stirred evenly. After innoculating with mold spores, the materials are filled into tray, and each tray contains about 2.5 kg of material. The tray are carried to the incubation room where they are arranged in "bricklap stack". The temperature of the incubation room is maintained at about 26-28 ℃. After 24 hour's incubation, the temperature of the Jiuqu in the middle stacks reached to above 30 ℃, it is needed to change the positions of the tray, especially, the tray in the middle should be placed on top or at bottom. In this way, one makes the Jiuqu's temperature evenly.
For the mycelial fungi to take oxygen, the next step is to turn the tray upside down to another empty tray. The Jiuqu which remains unbrokend for the Jiuqu being winded by growing mycelial fungi is transfered to the empty tray. This step is repeated three times.

2.3.2 "Da Qu"

"Da Qu", meaning the dimension of the Jiuqu is big than "Xiao Qu", is made from mixture of wheat flour and pea flour. "Da Qu" which is used in manufacture of Chinese spirits is a variant derived from wheat Jiuqu for rice wine making. It is a hard work but interesting, and needs sophiscated techniques and strict operating procedures. The wheat or larley and pea is ground to powder separately, and mixed together in a special proportion varied from place to place.Let's take the Da qu produced by Yanghe distillery as an example, wheat, barley and pea are (all in powder ) are mixed in the proportion of 50:40: 10. After adding suitable amounts of water to the mixed flour, A moisture content of about 40% is necessary to maintain good texture of the dough. the dough should be kneaded very evenly. Someone transfer the kneaded dough into a wooden mould. The wooden mould has the dimension of 195 × 138×75 cm. The next step is to tread the dough into the four corners of the mould firmly, then, the mould containing the dough is passed down to about 10 persons which is lined one by one. The body weight of each person should be different, ao as the dough is treaded not too firmly, not too loosely. After being removed from the mould, the rectangularly shaped dough is transfered to a incubation room, where the shaped doughs are placed on the straw with two layers, bamboo rods are used to separate the up and down layers. There is a space of 2 cm between each rows of Da qu blocks at the same layer. The Da qu block is covered with straw.
The temperature and humidity control is important to make good high quality "Da Qu". Incubation times usually last 4 weeks.
Although the temperature in summer is high, each distillery prefers to make their Da Qu in summer because the high temperature is favourable to the thermophilic microbes, and discourages the cryophilic bacteriua which usually are spoilage bacteria.
The Da Qu could be roughly divided into 2 types according to the incubation temperature. The "moderate temperature Da qu" is incubated with the maximum temperature usually below 50 ℃, and the "high temperature Da Qu" is incubated with the maximum temperature above 55 ℃, sometime,the maximum temperature of the Da qu may be reached to 65 ℃. It is believed that the production of distilled spirits by using high temperature Da qu enhances the arama and flavour of the distilled spirits, although the complicated mechanisms are still not clear.
During the cultivation of the Da Qu, the temperature pattern and humidity pattern are usually have three distinct phases ( moderate temperature Da Qu as an eaxmple):
First phase: this phase lasts about 9 days, and is charactered by rapidly increasing of temperature, and the humidity in the incubation romm is high. The spores of mycelial fungus begin to sprout, and mycelioid colonies appeared on the surfaces of the Da Qu. Due to the fermentation caused by the mycelial fungus, the Da qu blocks expand, and become soft. The temperature of the Da qu rises, water vapor evolves, humidity in the incubation room is very high. It is the first time to open the windows and doors to disperse the humidity, and turn over the Da qu block. To obtain uniformity, the location place of the Da qu blocks should be arranged again so that the block located in the centre be placed in the edge, and it is the same the other way around. In the first phase, usually, turning over the Da qu repeated six times. The major effort was directed towords obtaining good growth of mycelia and spores by culturing them at 30- 45 ℃, the Da qu blocks sometimes became heated to about 56 ℃. The details of the whole operating are difficult to discribe here.
Second phase: This phase lasts from the 10th day to 17th day. The temperature of the Da qu gradually rises. by turning over the Da qu, the temperature is controlled within 30-46 ℃ . It is needed that temperature change be smooth, and the water vapor inside the Da qu volatilize greatly. Turning over the Da qu and changing the position of each Da qu is done as that described before.
Third phase: Now the weight of the Da qu becomes light, and the Da qu is dry. It is better to allow the room temperature decrease smoothly. Turning over the Da qu is done as the usual method. In the traditional process, when the Da qu is dried, and temperature of the Da qu dose not rise, all the Da qu are heaped up in a corner of the incubation room, and are covered with straws. In this way, the temperature of the Da qu will rise again and the water content inside of the Da qu will evaporate further.
Every distillery persists in their own particular traditional methods in preparation of Da qu. For eaxmple, in Maitai distillery, the manufacturer of the most famous Chinese spirit, Da qu used is belong to high temperature Da qu, so the maximum temeprature during the Da qu cultivation may be over 65 ℃; and in Feng Jiu Distillery, during the cultivation of the moderate temperature Da qu, the maximum temperature of the Da qu is rearly beyond 46 ℃.
Good Da Qu is yellowish- to greyish- white color and has a good growth of mold mycylium throughout the mass. The Da qu should contain approximately 12 % moisture.

2.3.3 Xiao Qu Traditional Xiao Qu production

Xiao Qu has been used in rice wine brewing from ancient times to present, mainly in Southeast China. It was used mainly for rice wine brewing in ancient times. With the development of distilled spirits, the Xiao Qu also found its uses in this industry.
The primitive methods were very simple. The leftover ( remained steamed rice ) was a suitable substrate for microbial growth. Traditional preparation procedures are described below:
First the rice was ground into powder, then the powder was mixed with special liquid made by steeping herbs or hop with water. the ingredients were kneaded like a dough, then filled into a box, press the rice dough firmly into corners of box, and smooth the surface. cut the rice dough into pieces with a knif, make the pieces be shaped like a round ball. The most important thing is to select old Jiuqu, which should be as good as possible, as seed Jiuqu. The seed Jiuqu was used to inoculate the rice dough ball. Usually, the old seed Jiuqu is selected on the basis of rice wine quality made in last batch fermentation. Due to successive screen and isolation of the Rhizopus spp. from generation to generation, high quality strains were preserved and maintained and handed down from ancient times. The primitive screening and isolating methods invented in Song Dynasty had contributed a lot to modern microbiology.
This is the first discription on artificial inoculating Jiuqu medium although the seed Jiuqu was not strictly a pure culture. Chinese herbs and perfumes (spice) are also added to the rice flour to make the Xiao Qu which is called "YAO Qu"
The famous Xiao Qu was produced in Shaoxing and Ning Bo, Zhejiang Province. Rice Jiuqu production using indigenous microbial flora is best illustrated with the Shaoxing rice Jiuqu process. The flowchart of production process is briefly outlined below.

     dried Laliao ( a kind of Chinese plant) rice                water
               ↓                            ↓                  │
     Pound the Laliao in a mortar      ground (50 mesh)          │
               ↓                            ↓                  │
            sun-dried                      screening             │
               │                            │                  │
                      mixing and
                      transfered to Jiuqu tray
                      Treading underfoot
                      cutting to cuboid shape
                      rolling  to make it shaped like a round ball
                      add old koj  powder, let  it  adhere  to  the
                      surface of the ball
                      incubation in vats, and covered with straw
                          ↓ Trun over intermittently,
                      Xiao Qu (Shaoxing Xiao Qu) Pure cultured Xiao Qu and mixed cultured Xiao Qu

The microorganisms grown in the Xiao Qu are mainly Rhizopus spp. (Rhizopus oryzae, R.chinensis), Aspergillus spp. and yeasts. During the period from 1940's to 1950's, scientists isolated as many as 828 strains from Xiao Qu around the country, in which 643 strains belong to the Rhizopus genera. Rhizopus spp. have the ability to excrete not only amylase and glucoamylase, but also zymase. This illustrates why the rice wine makers use only Xiao Qu as both a sacharafying and fermenting agent.
We will take the Xiao Qu made by using Rhizupos sp. and yeasts as an example for illustrating the preparation procedures for the mixed cultured Xiao Qu. RHizupos sp. is grown in the medium based on rice meal or wheat bran, and yeast is cultured in Xiao Qu extracts and harvested by sedimentation. Cultured Rhizupos sp. and yeasts are mixed in a ratio of 50:1. The mixed culture can be used for making seed mash for rice wine. It was reported that using rice Jiuqu made with the mixed culture method has the advantages of easy of mass cultivation of moulds and yeasts, and the speed at which they grow. It is also possible to shorten the time required for rice wine fermentation due to the strong power of the saccharifying and fermenting agents. It is obvious that high yield and concentration of ethanol in the fermenting mash can realized by using the mixed culture Xiao Qu.

2.3.4 Red Rice ( Ang-kak) Introduction to red rice in general

Red rice and its use in alcoholic drinks and food industry were first mentioned in the literatures of Song Dynasty,and the traditional techniques of making red rice were recorded in Li Shizhen's <> ( a monograph of Chinese medicine),Song Yinxing's < < Tian Gong Kai Wu>>, and << Me E Xiao Lu>>.
The traditional producing areas of ang-kak was centered in South China, such as Fujian Province, Zhejiang province, Jiangsu Province, Jiangxi Province, and Taiwan Province. Gutian in Fujian Province has been the most famous red rice production center.
Application of the red rice
Red rice (ang-kak, ankak, anka, angquac, beni-Jiuqu, aga-Jiuqu) has been used in the fermentation industry for preparation of red rice wines and foods such as sufu ( or Dou- fu- ru in Chinese, a mold -fermented soybean curd product;), fish sauce, fish paste, and red soybean curd ( a cheese-like product used as a spice).Because Large quantities of hydrolytic enzymes shch as α - amylase, β - amylase, glucoamylase, protease, and lipase are produced by Monascus spp. which break down the rice constituents during growth and penetration of mycelium into the kernels. Pigments produced by Monascus purpureus and M. anka on rice have been used as household and industrial food colorants. The main pigments produced by Monascus spp. are monascorubin (red),rubropunctatin, monascin (yellow) , anka- flavin, rubropunctamine, and monascorubramine.
In addition to its value as a colorant, ang-kak may also possess therapeutic properties. Ailments and diseases purportedly cured by ang -kak included indigestion, bruise of muscle, dysentery and anthrax. Traditional preparation procedures

Red rice could be classified into four types, Ku Qu, Qing Qu, Se Qu and Wu Yi Hong Qu, Due to the differences in their raw materials and production methods.
Ku Qu is mainly used for making rice wine, Among the four types of red rice, Ku Qu is most heavy.
Qing Qu may be used for making rice wine or as colorant for food. Se Qu is mainly used as colorant for food, and its weight per unit volumn is the lightest, due to the longest fermentation time.
Wu Yi Hong Qu is a mixed culture of Monascus sp. with Aspergillus niger.
Traditional methods for manufacturing of red rice were very complicated and time-consuming, and through the ages, these techniques had acquired an element of mystery and wonder. Before making red rice, it was needed to get "seed red rice" as a starter. The techniques for seed red rice were kept secretly by masters. The seed red rice was supposed to have sexual distinction. The so called "father seed" and "mother seed" were manufactured in different ways.
The traditional techniques of making red rice were recorded in ancient books mainly published in Yuan Dynasty (1271-1368 A. D. ) and Ming Dynasty ( 1368-1644).
The "fermented rice wine mash" or red rice itsself were used as a starter (seed). Non-glutinous varieties of rice are most suitable for preparing ang-kak, since kernels of glutinous varieties tend to stick together and thus reduce the surface to volume ratio of solid material which is so critical to pigment production. The best raw material was long-shaped non glutinous rice. It was first washed, soaked in water for about 1 day or more, and drained thoroughly. The moist rice was then cooked. Upon cooling, the steamed rice was mixed with diluted vinegar solution or solution of alum to acidify the raw material (because the Monascus spp. are acidophilic), then was inoculated with "fermented red rice wine mash". The inoculated rice is thoroughly mixed and then incubated at appropriate temperature.During the first severals days, the rice will have taken on a red color and should be stirred and shaken to redistribute the moisture and kernels with respect to depth from the surface of the fermenting mass which should be spread out and piled up in turn. It may be necessary to add some water to replenish moisture lost during incubation. Within about 2 weeks, the rice would take on a deep purplish red color and kerneals should not stick together. Pure cultured red rice production

After the founding of the People's Republic of China, 11 strains of Monascus spp. had been isolated by the Institute of Microbiology, Academia Sinica. Pure cultivation of red rice was spreaded, and traditional operating procedures were also popular. Large- scale production of red rice with the "through-flow system" ( thick-layer bed aerated cultivation ) had been recently developed in Zhejiang Province. Besides as saccharifying and fermenting agents used in rice wine brewing, the red rice is used as a colorant mainly for food and as medicines. Large-scale production of colorant by extraction methods has developed quickly recently, and most products are exported to foriegn countries, for the red rice is considered as a safe food additive.
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