Study On The Processing Technology Of The Lotus Seed Powder And It's Application

This paper is something about the extruder cooking. The HuNan lotus is extruded by DS32 Twin-Screw Extruder under different condition of processes. The change of the degree of gelatinization and the density of the samples are studied under the different materiel moisture content,barrel temperatures and screw speed. Based on these, the major component and physic-chemical characteristics of the lotus and the lotus which had been extruded are studied. This article studies the feasibility of making the lotus seed paste from lotus seed powder, and its formula and the processing technology are studied. The main results are as follow:The degree of gelatinization and the density of the samples change largely under the different materiel moisture content and screw speed. The degree of gelatinization rises with the chance of the screw speed form 15 to 40×7r/min, while the density of the samples falls. Both of them change largely. The density of the samples goes up with the chance of the materiel moisture from 10% to 25%. And the degree of gelatinization reaches the top when the materiel moisture is 15%. Both of the degree of gelatinization and the density of the samples change a little under the chance of barrel temperatures.The texture of the lotus extruded changes a lot. The starch granule structure disappears. And the internal structure of lotus seed is more closely and its surface smooth, while after extruding it increasing gap and the surface is even. Because of linking with starch, the free fat largely reduces and left less than 30%. Every amino acid reduces more or less, and the total amino acid reduce 5.83%. Most of the free amino acid rise, while some of them reduce. But the total free amino acid arise 2.24%. The protein hydrolysis rate rises obviously. The total sugar and starch change a little. And the degree of gelatinization arises from 11.9% to 88.6%. The amylase, blue number of iodine and reducible carbohydrate increase more or less. And the starch hydrolysis rate increase largely.The aerated density reduces with decreasing of the particle size, while the trapped density changes little. The materiel moisture content has a little to do with the aerated density and trapped density. Overall the density of the lotus seed powder which extruded is larger than the one before extruding. The angle of repose and the angle of slide increases with decreasing of the particle. Both of them change a little with the chance of the materiel moisture content. The compression index, the angle of repose and the angle of slide are all show that the lotus seed powder is poor liquidity.The water absorption and water solubility index are both increase largely after extruding, while the oil absorption decreases. The stability of the lotus suspension is better than the one which extruded. And both of the stability improves by whipping. The foam ability and its stability of the lotus suspension are better than the one which extruded. And the frozen stability of the later one is better than the before one, and both of them decrease by suspension.The viscosity of the lotus seed paste increases with the increasing of the concentration of the NaCl, glucose and sucrose. And it decreases with the higher temperature. The propriety intensity of the acid and the alkali also increase it. And the lotus seed paste is pseudo plastic fluid.Traditionally, the lotus seed paste is made from the whole lotus seed. This article studied the feasibility of making the lotus seed paste from lotus seed powder. The result showed that it is feasible to make the lotus seed paste with lotus seed powder, and its formula and the processing technology are studied.The formula is: lotus seed powder (150 head)∶white sugar∶p eanut oil=10∶1 0∶7. And the processing technology is: the lotus seed powder is sautéfor 60 min at 140℃→adding sugar solution, and mixing uniformLy (sugar∶water=10∶24)→adding half of the peanut oil, and mixing it till most product is dry→reduce the temperature to 110℃→adding the another half of peanut oil→take it out till the moisture content of the product is seemLy→cooling→packing.