Institute of Agro-food Technology, Jilin Academy of Agricultural Sciences
The People’s Government of Jilin Province and Chinese Academy of Agricultural Sciences signed an agreement in 2004, to jointly establish Northeast Agricultural Research Center of China (NARCC), on the basis of Jilin Academy of Agricultural Sciences (JAAS).
NARCC covers a total area of 791.8 hectares, and total building area about 100000 square meters. There are more than 1500 pieces of large-sized and advanced instruments. NARCC has built up more than 30 research and development platforms, such as centers at national and provincial levels, and key laboratories.
Food Research at NARCC
1. Dairy Technology
Institute of Agro-food Technology of Northeast Agricultural Research Center of China (Jilin Academy of Agricultural Sciences) has started research in dairy science for over ten years, and achievements have been made in the research and development of fermented milk, milk beverage, soy milk, and ice cream.
The Dairy Technology Laboratory of the Institute, with about 10 staff members (3 with Ph.D. degree), focuses research on the improvement of raw milk quality, biotechnology of lactic acid bacteria, enzymatic techniques for dairy processing, and milk-derived bioactive substances, aiming to provide technological supports for the development of dairy industry in Northeast China. The laboratory, with a total area of 1500 m2, has advanced experimental instruments including fluorescence micro-imaging system, texture analyzer, automatic nitrogen determination apparatus, automatic fermentation system, milk analyzer, PCR instrument, freeze dryer, ultra-low temperature refrigerater, centrifuge and gel imaging system. There are also pilot production lines for fermented milk products and milk beverage.
Current research projects of the laboratory include “Molecular modification of fungal chymosin used for cheese production and development of bioengineered chymosin preparation” (National “863” Program); “Studies on the tolerance and colonization mechanism of probiotic lactobacilli” (Natural Science Foundation of China); “Studies on exopolysaccharides produced by lactic acid bacteria of Chinese traditional sources and novel applications in functional fermented dairy products” (Sino-Finnish Cooperative Research Project supported by Ministry of Science & Technology of China); “Development of novel lactic acid bacteria starter cultures and chymosin”( Jilin Science & Technology Program).
1.1. Biotechnology of Lactic Acid Bacteria
1) Isolation, identification and screening of lactic acid bacteria
Lactic acid bacteria are isolated and identified from traditional fermented products in Northeast China and Inner Mongolia. Studies are carried out to screen strains with good production performance, strains producing functional compounds (exopolysaccharides, bacteriocins, etc.), and probiotic strains, and finally to develop high-efficient functional starter cultures.
2) Studies on the physiological characteristics and colonization mechanism of lactic acid bacteria
Studies are performed on the tolerance of lactic acid bacteria to low pH of stomach and bile, the adhering capacity to intestinal epithelial cells, and the ability to inhibit food spoilage bacteria or pathogens. The functionality of capsular polysaccharides produced by lactic acid bacteria.is also studied.
3) Studies on the gene regulation of metabolic pathways of lactic acid bacteria
The key enzymes in the metabolic pathways of lactic acid bacteria are studied by gene knockout, gene silencing to supress the expression, and by overexpression of the enzyme, thus to regulate the metabolic pathways and the end products.
4) Applications of lactic acid bacteria in fermented dairy products, meat products, and vegetables
Lactic acid bacteria are used as starter cultures to improve physiological and functional characteristics, to produce function-specified or probiotic fermented foods.
1.2. Modification of exopolysaccharides from lactic acid bacteria
To better difine the relationship between the structures and biological properties, a program was started in our research group to modify the structures of EPS.
1) Chemical modification of exoplysaccharides (EPS)
Sulfation of EPS: The hydroxyl groups of EPS are sulfated by chlorosulfonic pyridine to give sulfated products.
Phosphorylation of EPS: Chemical phosphorylation with POCl3 in pyridine is used for direct one-step introduction of the monophosphate function into unprotected EPS molecules.
2) Enzymatic degradation of EPS
Enzymatic degradation of exopolysaccharides into their oligomers is mainly based on the use of microbial hydrolases and transferases.
3) EPS biosynthesis regulation by gene engineering
Based on the available genetic information, genetic modification of eps genes should lead to EPSs with a different repeating unit or with a different chain length. It was established through chemical mutagenesis or inactivation of the glycosyl-transferase gene, that lactic acid bacteria can assemble and export variants of the EPS structure with truncated sidechains.
1.3. Bioengineering of Chymosin
Our research focuses on overexpression of the chymosin gene (native or structurally modified), and economic production of chymosin via microorganism fermentation, thus to lower the costs of cheese making.
1) Cloning and expression of the bovine chymosin, and its production by fermentation
The bovine chymosin gene is cloned from the mucous cells of calf stomach. The enzyme is expressed in E. coli and food-grade yeast cells, and it is separated and purified from the fermented liquors.
2) Cloning, expression and molecular modification of a fungal chymosin
A chymosin gene from Mucor pusillus was cloned, and molecular modification of this enzyme by using computer simulation methods is performed to improve the interaction between the enzyme and casein. Mutagenesis of the enzyme is carried out to obtain mutant enzyme with increased milk clotting activity, higher specificity and decreased thermostability.
2. Soybean Processing Technology
The Northeast region of China is the major soybean planting area with a total yield about 50% of the whole country. In recent years, the nutrition, health value and functional properties of soybean have been further confirmed, and soybean processing technology and novel product development have made substantial progress. The Soybean Processing Lab focuses on research regarding key processing technologies, equipments of soybean processing, to meet the technological needs of soybean industry.
1) Key technology research of functional soy proteins by structural modifications with enzymatic, physical, chemical and biological methods, to enhance the functional properties of soy protein, and to produce functional soy proteins for special use.
2) Industrialization of traditional soybean processing methods for the production of various soybean products utilizing the methods of modern food technology, food engineering, and biotechnology.
3) Exploitation of bioactive components in soybean, and studies on separation and purification, mechanism of action and functional evaluation of the soy isoflavones, peptides, polysaccharides, oligosaccharides, and lecithin, etc.
4) Exploitation of novel soybean products such as fermented soy milk, soy cheese, imitated meat products, soy chocolate, and soy pudding, etc.
5) Studies on the standards and quality management system for traditional and novel soybean products according to the HACCP and GMP systems.
3. Cereal Food Technology
Jilin Province is one of the biggest grain producers in China. Developing down-stream processing of cereal foods can enhance their conversion into different food products with added-values. The use of novel high-tech methods may help to maintain the original nutritional value of raw materials, and to produce high quality foods with favorable nutritional and organoleptic characteristics. The aims of Cereal Food Technology Lab are to develop novel cereal foods by the use of biotechnology, ultra-high pressure technology, special extraction and chromatographic methods.
For corn research, the studies focus on the molecular modification, anti-aging, and prevention of retrogradation of starch, to develop anti-aging food additives, to develop specialized corn meals, to solve problems with low gluten of corn meals with improved elasticity and malleability, to expand the use of specialized corn meals in dumpling, bread, steamed bread, and noodles, and to comprehensively utilize by-products of corn starch plants.
For miscellaneous cereal research, to develop methods for effective extraction of healthful components in grains, and to develop functional and snack foods.
4. Comprehensive Utilization of Agricultural Special Products
Jilin province is rich in speciality resources, especially in Changbai Mountain, which is a land full of precious natural creatures and plants. These resources provide great advantage and potentiality for the development of Jilin's economy. To study and develop the natural, healthy, functional foods from these resources helps to accelerate the ecology construction and comprehensive exploitation of the resources.
1) Processing technology for special functional maize food, including preservation of sweet-sticky maize, maize milk technology, maize sausage technology.
2) Processing technology for special functional food, including edible wild herbs in Changbai Mountain, bioactive soybean fibre, and edible fungi, and for comprehensive utilization of maize pollen, processing of the wood frog oil cosmetics, extraction and separation of special functional components, etc.
3) Comprehensive utilization of fruits and vegetables in healthy drinks.
4) Key technology for the production of biodiesel, including the equipment for the production of biodiesel with soybean oil, acidified oil and so on.
5. Food Biotechnology
The Food Biotechnology Lab focuses on the isolation from the nature the beneficial microorganisms, and to improve the microorganisms by genetic engineering for specific uses.
1) Functional food additives –lycopene： By knockout of the key enzyme, lycopene cyclase of the isoprenoid pathway in Rhodotonda, to increase the accumulation of the intermediate product lycopene.
2) Isolation and genetic engineering of microorganisms to produce polylactic acid (PLA) and polyglutamic aid (PGA) by fermentation of corn starch.
3) Identification, separation and cloning of microbial genes encoding metabolites with interesting physiological activities, and design of transgenic bioreactors.
4) Application of biomolecular techniques in the examination and classification of food microorganisms, focusing on the use of 16s rRNA and ITS conserved sequences.
5) Exploring novel food enzymes and cloning of their genes for application in food industry.
Add: No.1363, Caiyu Str., Changchun, Jilin, P.R.China
P.C.:130033 Tel: +86-431-87063145
Fax: +86-431-87063075 E-mail: email@example.com
Contact: Mr. Jie Zhang