With the continuous enhancement of consumers' health awareness, the demand for low-sugar and functional foods has experienced an explosive growth, which has brought unprecedented development opportunities to the sugar industry. 

Starch is rich in sources. According to its structure, it is mainly divided into amylose and amylopectin. Amylose is composed of glucose connected by α-1,4 glycosidic bonds. Amylopectin, on the other hand, is highly branched starch, with branches connected by α-1,6 glycosidic bonds and usually having a larger molecular weight. The composition ratio of amylose and amylopectin varies greatly depending on the source of the starch. In common starch, the content of amylose and amylopectin is approximately 25% and 75% respectively. 

Different sources of starch, processed using various techniques, can yield different derivatives of starch sugar, such as dextrin, amylose, resistant dextrin, oligosaccharides, fructose-glucose syrup, malt syrup, glucose, etc. 

These starch sugars, due to their unique physical and chemical properties as well as functional characteristics (anti-digestion, bulking, film-forming, sweetness, prebiotics, nutrition, etc.), are gradually becoming indispensable components in numerous food formulations. They have achieved remarkable success in various fields such as food and beverages, health supplements, etc., and their application scope continues to expand. 

The production process of starch sugar derivatives can be roughly divided into: mixing, gelatinization, enzymatic hydrolysis, filtration, desalination, concentration, and spray drying. The production process flow is as shown in the following figure:

slurry → dextrinization → enzymolysis  →  filtration  →  Decolorization/Desalination → concentrate (a liquid) → Spray drying

                                                ↓                           ↓

                                        Liquefied               plate frame

                                  saccharification       Ceramic membrane

                                    debranching             Ultrafiltration

                                    isomerization           Nanofiltration

                               transglycosylation            

The key enzymes in starch sugar production are as follows:

After the starch solution undergoes processes such as gelatinization and enzymatic hydrolysis, it usually contains undissolved proteins and granular substances, which need to be filtered and clarified. The enzymatic solution typically has a solid content of around 30%, and the material liquid temperature is 50 to 60 degrees Celsius. Through plate and frame filtration, most insoluble substances are removed, but the plate and frame filtration has poor precision and cannot meet the turbidity requirements of the material liquid. 

Membrane filtration separation technology, with its unique advantages, has begun to gain prominence in the starch sugar production field, leading the industry towards the direction of high efficiency, environmental protection and energy conservation. 

The sugar solution becomes clear - ceramic membrane 

Ceramic membranes have the characteristics of high temperature resistance, corrosion resistance, strong pollutant adsorption capacity, high filtration accuracy and large filtration capacity. By using high-precision ultrafiltration ceramic membranes for cross-flow filtration, large molecules such as proteins and cellulose can be effectively retained. For liquid sugar used in glucose production, when filtered under working conditions, it can be concentrated by 30 times, with a filtration capacity of over 200L/㎡h. The trans-passed liquid has a turbidity of less than 5 NTU, and the sugar liquid transmittance (at 440nm) has significantly increased to over 80%. 

Sugar solution classification, decolorization, protein removal, endotoxin removal - ultrafiltration, nanofiltration 

Organic ultrafiltration or nanofiltration membranes have the characteristics of narrow pore size distribution and high separation accuracy, and they have unique advantages in the separation of homologous substances, decolorization, and protein removal. The membrane filtration system has the features of large processing capacity, linear scalability, and high degree of automated operation. Clarified liquid from ceramic membranes can be processed through different precision organic ultrafiltration membranes/nanofiltration membranes to achieve the precise separation requirements of different starch sugar products. 

In industry, organic membrane ultrafiltration/nanofiltration is often used to remove residual enzymes, endotoxins, and large molecular pigments from the liquid. By optimizing the membrane material, precision, and filtration area, under conditions of a liquid temperature of approximately 60°C and a concentration of 30%, the filtration indicators such as the transmittance of the filtrate at 440nm (>95%) and endotoxin content <5 EU/ml can be achieved; the direct chain starch can be separated in stages, and the product can be directly used for film formation; the experimental separation of cyclodextrin raw material drug was carried out, and the molecular weight distribution curve met the quality standard requirements. 

Concentration of low-concentration sugar solutions - nanofiltration, reverse osmosis 

Nanofiltration and reverse osmosis technologies can be used for the concentration, desalination and reduction of COD in low-concentration sugar solutions, enabling low-cost concentration of sugar solutions, reducing evaporation energy consumption, increasing water reuse rate, saving a large amount of energy costs for enterprises, improving resource utilization efficiency, and achieving green production. 

Wuhan Bona, as a leading company in the field of membrane separation technology, focuses on the research and application of this technology, and is committed to providing customers with comprehensive membrane filtration solutions. In the areas of starch sugar products (such as dextrin, cyclodextrin, amylose, resistant dextrin, oligosaccharides, fructose-glucose syrup, maltose syrup, glucose, etc.) sugar liquid ceramic membrane clarification filtration, organic membrane ultrafiltration, nanofiltration separation, nanofiltration, and reverse osmosis RO concentration, it has accumulated rich process development and engineering experience. 

Based on the individualized needs of customers, we can provide tailor-made process design solutions, ensuring the scientificity, rationality and efficiency of the process. At the same time, the company also offers high-quality membrane filtration equipment to guarantee the stable operation of the system and safeguard the production of customers. In addition, the professional technical support and the complete after-sales service team can promptly respond to customer needs and solve various problems encountered by customers during use, eliminating customers' worries and allowing them to fully devote themselves to production and operation, enjoying the many conveniences and benefits brought by membrane separation technology.