| The research & development of forestry byproduct such as Jew's-ear and machinery for processing forestry byproducts are weak fields of food industry in China. Pased on the theory and laboratory research of "Technology for making green top-grade paper-shape Jew's-ear and recombination technology for making Jew's-ear", this paper has made a in-depth research into the variation of cells structure during pressing and shaping process. A thermal compressive molding machine with automatic temperature controller has also been designed and manufactured based on analyzing the heat transfer processing and confirming the parameter of thermal compression. Also, a demonstrative factory of Jew's ear paper product was built up. The main achievements are as follows.1. Research on transfer of water in Jew's-ear indicates that Jew's-ear absorbs water mainly through the gelatine existing between mycelial cytoplasm and stroma between cells. Most of the gelatine exists in the middle layer between the compact layers of ventral and back sides. Research on water losing through drying process and water recovery rules shows that water recovery of Jew's-ear may be best obtained in 40℃ water whose weight should be 10 times that of the Jew's-ear. When various factors were taken into consideration, it is found that Jew's-ear is applicable to be dried with hot air of 70℃.2. The thermal compressing process for paper-shape Jew's-ear is fully studied. Orthogonal experiment has been applied to determine optimal technical parameters for the thermal compressing process and the results demonstrated that the most influential factor is water content of raw material. The optimized results are: water content of raw material 15%, temperature 60℃, compressive pressure 0.5MPa and time 180s.3. Three schemes have been designed according to the technical requirements and the requirements for the thermal-compressed Jew's-ear product (Heating temperature 60-65℃, pressure >0.3MPa, dimensions of two module mold 90 x60x30mm, size of finished product 90 x 60x 2 mm), which are respectively spiral clamped design, second wheel loading design and clamped lever combined with second wheel design. The optimal design is determined and a thermal compressing machine with automatic temperature controller has been made to produce paper-shaped Jew's-ear. The feasibility of the demonstrative factory of Jew's ear paper was analysed at last.4. For the first time, the changes of internal microstructure of Jew's-ear on both transverse and longitudinal section have been studied. The results of variance and cluster analysis of hyphal angle rules before and after compressing process proved that the arrangement of mycelium are more orderly after compressing process. SEM examine test shows that the surface cells of Jew's-ear are smoother and the shape is more regular after compressed. TEM tests show that the internal structure of Jew's-ear cells has not been destroyed, the diameter of the mycelium cell is l~3μm and the arrangement of mycelium cells are more regular. Property analysis shows that the water recovery capability of Jew's-ear has been improved after compressed. Ingredient analysis shows that contents of protein, ash, fat,carbohydrate and coarse fibre are basically remain unchanged.5. For the first time, superfine pulverizing powder of Jew's-ear with excellent properties has been developed through vacuum frozen-drying and superfine pulverizing process. TEM tests show that the cells were smashed, the minimum size of the cell scrap is 0.1 μm, and the average size is 0.5-1μm. This test results further proved that the cells have been smashed, the internal substances have been released and some of the protein molecular have been broken. The analysis show that the gross content of amino acid has been increased. The primary reason were given in this paper. HPLC test results indicate that vitamin BI has not been destroyed; on the contrary, vitamin B2 is destroyed to a larger extent. Property analysis demonstrated that due to the effect of smaller molecular size, the voi...
|
PDF Full Text Request