Preparation Of Essence And Residues Powder From Flammulina Velutipes And Evaluation Of Their Physical-Chemical Properties

Flammulina is an edible mushroom in the transmission. It has high nutritional value, especially high content of lysine and arginine, known as good for the intellectual development. Recent studies show that Flammulina has anti-tumor, immunomodulatory and antioxidant effects. With the expansion of the cultivation, the traditional consumption patterns can not meet the needs of development of Flammulina's industry; accelerating the development of Flammulina processing industry is imminent. This paper is to explore an initiatory processing method, divided Flammulina into soluble and insoluble fraction, and dried into a power, respectively. We hope that through this approach can expand the applications of Flammulina in the food processing industry and lay the foundation for the finish machining.1. Using enzymatic extraction method, wet ultrafine grinding extraction method, ultrasonic extraction method, wet ultrafine grinding and ultrasonic wave extraction method extracting soluble components from Flammulina, and the single factor optimized extraction results were compared to select the best one. The results showed that the wet ultrafine grinding extraction method and wet ultrafine grinding assisted to ultrasonic wave extraction method have the highest extraction rate; to simplify the processing we choose the wet ultrafine grinding extraction method to extracting soluble components from Flammulina.2. Response surface methodology (RSM) was employed to optimize conditions of wet ultrafine grinding extraction method of water-soluble polysaccharides and total solid. Results showed that the optimum processing parameters were:the gap of colloid mill at 40μm, extraction temperature at 86℃and extraction time at 171 min. The concentration of solid was 9.03±0.25mg/mL and water-soluble polysaccharides was 418±3.21μg/mL, and yield of solid rate was 13.5%, yield of water-soluble polysaccharide was 3.63%.3. The microwave vacuum drying of Flammulina residue include two parts, color protection and drying process. The treatment of color protection was immersing the residue into the protecting color liquid at a certain concentration at room temperature. Orthogonal test was used to optimize the addition of the three color protection agent(citric acid, Vc and EDTA-2Na), and the L* value was used to evaluated the optimizing results. Results showed that the optimum concentration of the color protection liquid was:citric acid at 0.15%, Vc at 0.15%, EDTA-2Na at 0.2%. The stage drying method was used on drying Flammulina residue. The primary drying parameters were:the vacuum at 0.08 MPa, the microwave power at 350 W, drying time at 40 min, after primary drying the moisture contends was 20%. The second drying parameters were:the vacuum at 0.04 MPa, the microwave power at 200 W, drying time at 50 min, after second drying the moisture contends was bellowed 8%. The feed rate was 1000 g every time.Microwave vacuum technology was used for the preparation of the essence Flammulina. Orthogonal experiment was employed to optimize drying conditions (vacuum degree, microwave power, and addition of malt dextrin). The optimum processing parameters were:the vacuum at 0.04 MPa, the microwave power at 700 W, and the addition of malt dextrin at 5%.226 min of drying time was consumed and 87.6% of yield rate was obtained.4. In order to facilitate the using of Flammulina essences and residues, the physical-chemical properties and antioxidant activity in vitro were determined. The results showed that the essences of Flammulina has good solubility and fluidity; the contents of total free amino acid was 25±1.2 mg/mL; the lysine was 267±12.3μg/g; the arginine was 249±9.8μg/g; the polysaccharides was 9.4±1.32mg/g. The essences of Flammulina has good antioxidant activity. The solution at mass concentration of 10%, the scavenging rate of hydroxyl radical, superoxide anion and DPPH·was 85%,91% and 77%, respectively.The residues power of Flammulina has good fluidity and dispersity; the contents of total protein was 19.6±0.69 mgN/g; the total dietary fiber was 721±9.3 mg/g; the soluble dietary fiber was 11.5±1.4 mg/g. The residues power of Flammulina has some antioxidant activity. The suspension at mass concentration of 10%, the scavenging rate of hydroxyl radical, superoxide anion and DPPH·was 66%,79% and 55%, respectively.