Cartridge

The cartridge is a vertical container with a flat bottom, which can be directly heated and sterilized on a gas furnace or an electric furnace. However, it is more commonly used to put the whole in a sterilizer and sterilize it with steam. The cassette tank can sterilize wort and cultivate pure yeast in the laboratory to meet the needs of expanded yeast cultivation equipment.

Cartridge structure

The top of the cassette tank is sealed, and the top cover is equipped with: 3 clamps, an insulating lifting ring, air holes for oxygen ventilation/exhaust, and diaphragm connectors for checking pure yeast culture. Standard cartridges come complete with connecting tubing and a separate filter for sterile oxygen ventilation. Cassettes are designed for easy placement directly into the retort.

Advantages of cartridges

It is convenient for aeration; it provides a safe condition for yeast transfer; it is easier to clean; and it is convenient for transportation.

Cartridge Process Stages for Yeast Expansion

The main task of yeast expansion is to cultivate a sufficient number of strong purebred yeast within the specified time, that is, to ensure the robust growth of the cultured yeast during the expansion process, while not allowing other microorganisms to grow. In the stage of laboratory expansion, 70% of the infected bacteria are in the Karst jar stage, because this stage cannot be automatically controlled like large-scale production. Compared with other laboratory expansion, the volume is larger and the control is more difficult. Therefore, how to reduce the chance of bacterial contamination in the Karst tank stage has become a problem that every expansion personnel must think about.

Previous Cassette Can Process

1. After the culture of the Erlenmeyer flask is completed, pour the bacterial solution from the inoculation port of the Karst jar into the Karst jar. In order to reduce the chance of infection, a fire ring is specially made, and the bacterial solution is poured from the inoculation port through the burning fire ring during inoculation. There are three disadvantages in this method: ① During the inoculation process, the fire ring is easy to burn the yeast species in contact with the fire, which increases the mortality of the yeast; With the aseptic wind protection of the ultra-bacteria table, and the fire power of the fire ring cannot be very large, the bacteria in the room can easily enter the Karl Fischer tank from the inoculation port, thereby increasing the chance of infection. ③ During the inoculation process, the bacterial liquid is easy to stick to the edge of the inoculation port, which increases the chance of bacterial infection.

2. The filter bottle (must have good pressure resistance) is used for the expansion of the Karst tank in the previous stage. During the cultivation process, the mouth of the filter bottle and the side pipe are wrapped with gauze, and the mouth of the filter bottle is replaced with a rubber stopper when inoculating the Karl Fischer tank. (There is a glass tube leading to the bottom of the filter bottle in the middle of the rubber stopper, sealed with a raw material tape and the rubber stopper, wrapped and sterilized in advance), and compressed air or oxygen is passed through the side tube of the filter bottle to pass the bacteria solution through the glass tube Press the yeast into the Karst jar from the sampling port of the Karst jar.

3. Compared with method 1, method 2 is not exposed to the air during the inoculation process, so the chance of bacterial infection is reduced, and the death of yeast caused by the inoculation process can be reduced, but this method still has limitations: The sealing requirements of the road are relatively high, and if there is a slight leakage, it may cause inoculation failure. ② There must be a sterile air source in the laboratory. If the air source microorganisms are unqualified, it will increase the chance of contamination. ③ Sterilize the bacteria in the pipeline before the inoculation of the Karst tank, and replace it on the suction filter bottle before the inoculation of the Karst tank, there is still a certain chance of bacterial contamination during the replacement process. ④ Two people are required to cooperate with the operation.