Influence of dextran in sugar production and its solution

Sugarcane is an important sugar crop in the world. China is a big sugarcane planting country, with an annual output of more than 12 million tons, accounting for about 10% of the world's total output, ranking third in the world after Brazil and India. As a kind of sweetener, white sugar has been widely added to all kinds of food. It can not only provide energy, but also give food a special taste. It has been deeply loved by the masses. At the same time, China has nearly 40 million people engaged in sugarcane planting and sugarcane production related industries.

Sugarcane is susceptible to microbial infection, especially if it is not fresh or has been damaged in a variety of ways, or is carried by bacteria from the outside. In the later stage of sugar refinery production, most microorganisms are killed, but a small number of microorganisms can reproduce in the workshop and some materials, and may even appear in the product.

In the cut cut of sugarcane, insect wounds, wind breaks or frost cracks and other places, or sugarcane is burned before harvest, or placed for a long time after harvest, this bacterium will multiply rapidly, forming mucous substances at the wound, consuming sucrose and producing glucan. They often breed at the dead corners of the sugar mill equipment, especially at the bottom of the sugar press juice tank, the bottom of the curving sieve and the bottom of the mixing juice box, and the resulting glucan sticks to form white beaded lumps, which is commonly known as "sugar cane rice".

Dextran is a polymer condensation of glucose with molecular weights ranging from tens of thousands to millions. In sugar production, dextran is mainly a glucose polymer formed by the metabolization of sucrose by microorganism such as Leuconococcus enterosus and Streptococcus, which is generally α-glucan. The fresh sugarcane contained little glucan, but the stale and infected sugarcane had a rapid increase in glucan content. For example, long cut sugarcane segments increased to 740 mg/(kg·°Bx) after 24 h, while the segments cut (about 250 mm) increased to 170 mg/(kg·°Bx) after 1 h and increased to 10 times after 24 h. The content of glucan in sugarcane harvested after burning at the same time was 1 ~ 3 times higher than that of unburned sugarcane. High temperatures and slime on the sugarcane surface increase bacterial activity. If the sugar cane is left after cutting for a long time, especially in the air with high humidity or unclean surroundings, the content of glucan can increase by more than 10 times. Every 250 mg/kg increase of glucan in cane juice means a 0.1% increase in sucrose loss. If the juice contains 0.1% glucan, the loss of sucrose will reach 0.4%. On the one hand, C. enterococcus converts glucose to dextran, on the other hand, it destroys fructose to form organic acids.

C. enterococcus is easy to grow in dilute sugar solution, and rapidly propagates in slightly acidic, neutral and at 50 ~ 60℃. It and a variety of microbes in sugar mills can form capsular-covered spores that are very heat resistant. Although most of them died under the temperature of 95 ~ 100℃, a few of them were just dormant. Once the temperature drops, it recovers. Therefore, both mud juice and filter suction machine may have bacterial reproduction, and some sugar mills have found that there is a large amount of sugar cane rice accumulation in the juice pipe of filter suction machine.

Dextran can obviously increase the viscosity of sugar solution, especially the intervention rate of high molecular weight dextran in high concentration sugar solution is 0.1% ~ 0.25. This is related to its high viscosity, large amount of glucose groups in the molecule and molecular structure close to sucrose. Dextran is easy to adhere to the surface of the filter, blocking the liquid channel and hindering filtration. Dextran increases the viscosity of the paste, impedes the crystallization of sucrose and increases the difficulty of honey separation. In the raw sugar refinery, the 0.03% glucan content of the syrup increases the purity of molasses by one degree. When the content of glucan in the syrup reaches 0.04% ~ 0.06%, the sucrose crystals in the crystallization process will become longer and even become needle-like. Most of dextran exists in sucrose crystal and is difficult to be removed by washing.

The effects of glucan and starch content on the filtration speed of raw sugar syrup were studied experimentally. The results showed that glucan could obviously affect the filtration speed of raw sugar syrup, and the simultaneous action of glucan and starch could also affect the filtration speed of raw sugar syrup.

In the press section, high concentration of glucan polymer often appears in the roller screen, curved screen, cane juice tray and other places in the press workshop, and these white objects will cause difficulties in the filtering of the juice.

In the clarification section, when the sugarcane juice contains a certain amount of glucan, it will be as the process into the sedimentation pool, in the process of subsidence, glucan can reduce flocculation efficiency, prevent colloid flocculation and the associated suspended in solution, leading to slow mud juice subsidence, increase the burden of filtering time and filtering, delay the whole production process.

In the evaporation section, the unremoved dextran in the sedimentation will still enter the evaporation tank with the clear juice. In the evaporation process, the presence of dextran will increase the viscosity of the solution, affect the heat transfer efficiency, and thus reduce the evaporation efficiency and increase the gas consumption.

In the sugar boiling section, high viscosity syrup is not easy to operate in the sugar boiling process, which reduces the crystallization rate and prolongs the sugar boiling time. At the same time, it has been pointed out that the presence of dextran can make the crystal formation abnormal. Moreover, the presence of glucan is easy to block the sieve, resulting in the difficulty of honey separation. If the viscosity of the paste is too large, the fluidity becomes worse, the cooking time is prolonged, the quality of the seed becomes worse, the probability of caramel generation becomes larger and the color value of the white granulated sugar increases, thus causing the quality of the white granulated sugar of the product to fail to meet the standard of high quality sugar. In the process of sugar boiling, 80% of glucan can enter the sucrose crystal at a steady speed, but can not be removed by honey washing, which will affect the morphology of sucrose crystal, resulting in incomplete crystal shape and rough crystal face.

Formaldehyde fungicide commonly used in sugar mills has been banned by the state. At present, our company has developed an economical, effective and environmentally friendly bacteriostatic agent for sugarcane sugar production instead of formaldehyde.

The dextran in the sugar industry is mainly dextran, which is a polymer of glucose linked by α-1, 6 glycosidic bonds. Its relative molecular weight ranges from tens of thousands to millions. The glucanase is divided into α-glucanase and β-glucanase according to the severing of different glycosidic bonds. The β-glucanase degrades the glucan linked by the β-glucosidic bond and the α-glucanase degrades the glucan linked by the α-glucosidic bond. The dextran produced by C. enterocheum contains a large amount of α-1, 6 bonds and a small amount of α-1, 2, α-1, 3 and α-1, 4 bonds. The content of dextran can be significantly reduced by adding α-glucanase from sugarcane.

By using the α-glucanase of our company, 50~85% of glucan can be degraded, the viscosity of boiled sugar and the purity of molasses can be reduced, and the content of glucan in the crystal can also be reduced by about 80%.

Music yeast α-glucanase specification

LJSWKJ-TM7

The α-glucanase is a compound enzyme preparation, which is divided into α-glucanase and β-glucanase according to the severing of different glycosidic bonds. The β-glucanase degrades the glucan linked by β-glucosidic bonds, and the α-glucanase degrades the glucan linked by α-glucosidic bonds. The dextran produced by C. enterococcus contains a large amount of α-1, 6 bonds and a small amount of α-1, 2, α-1, 3 and α-1, 4 bonds, thus inhibiting the growth of the bacteria. This product is a compound enzyme preparation, the main ingredients are food-grade enzyme preparation, the product is a food additive, is suitable for sugarcane sugar factory, beet sugar factory production safety substances, the whole process of sugar production without any adverse effects.

1、Technical indicators：GB26687-2011

2、Range of application

It is mainly used for bacteriostasis in the process of squeezing and storage of cane juice in sugar cane sugar mills and bacteriostasis of oozing juice from beet sugar mills. Action temperature: The effective action temperature range is 30-65°C. PH value: applicable PH value 3.5-6.0

3、Instructions

When used in the sugarcane squeezing process, the recommended dosage is 2-3 grams per ton of sugarcane. It can be added in the original solution or after dilution. In the production of sugar beet, it is added at the outlet of the leached juice, and 2-4 grams per ton of leached juice is added.

4、Packaging and storage

Packed in plastic drum, 25kg/drum. The product should be stored in a cool, ventilated, dry warehouse, not stored in the open air, and not mixed with toxic, polluted items or other sundries.

5、Food additive production license number：SC20145014001493

6、safety：

This product is a biological enzyme preparation, a non-flammable and explosive product, and a non-hazardous chemical. According to the requirements of the instructions, there will be no safety problems. Avoid inhalation of the mouth and nose. If the eyes are in contact with this product, wash them with water immediately.

7、Technical Advisory Services：

Technical Service Phone：0771-3926709  13707880269

E-mail:hlj269@163.com

manufacturer：Guangxi Le Yeh Biological Technology Co., Ltd.

address：The whole floor of the west side of the first floor, Building A, Nanning Technology Business Incubation Base, No. 25, East Section of Gaoxin Avenue, Nanning High-tech Zone, Guangxi