Study On The Non-enzymatic Browning Of Konjac Flour

In this experiment, A. albus flour and A. konjac flour as raw materials, ethanol treatment on the A. konjac flour components removal Maillard reaction, causing non-enzymatic browning of free amino acids, free sugar, total phenol components to determine the type of non-enzymatic browning reaction simulation Maillard reaction, the reaction products of A. konjac flour United States, its main findings are as follows:(1) It is technology that color of konjac flou is changed by ethanol extraction. We have konjac flour as raw material,by a single factor test and single factor analysis of the optimum level, and then analyse the color changed of konjac flour by orthogonal extraction, ratio of solid and liquid, ethanol concentration, temperature and time on, it's influence in decreasing order:the of ethanol concentration, ratio of solid and liquid, extraction time, extraction temperature.It is determine that the ethanol extract of konjac flour on the optimum technology for color change:50% ethanol concentration, extraction of solid to liquid ratio of 1:40, extraction temperature 35℃, extraction time 3h. The colors of A.albus flour and A.konjac flour are white, heated at 105℃for 4h, the colors of A.albus flour is from white into yellow, color of A.konjac flour is from white turned dark brown, the colors of two kinds of flour are the clean white extraction ethanol, color of these two konjac extracted ethanol are also white heated at 105℃for 4h, so it is showed that sugars, amino acids and total phenols are removed in konjac flour by ethanol extraction.(2) It is identified that component of non-enzymatic browning in A.konjac flour extracted by ethanol is changed. We determined the changes of chemical composition in A.konjac flour around the ethanol extraction, it was show that chemical compositions of A.albus flour and A.konjac flour are reducing by ethanol extraction, the content of sugar decreased 0.94% and 5.71%, amino acids decreased 0.38% and 1.13% and total phenolic decreasedl.55% and 9.62%.(3) It is identified type of non-enzymatic browning reaction. We determined the changes of chemical composition in konjac flour around the non-enzymatic browning, it was show that around the non-enzymatic free sugars in A. albus flour and A. konjac flour was reducing without heat treatment, glucose and amino acids are reduced, because they were participated non-enzymatic browning reaction, the content of total phenol was increased,due to non-enzymatic browning reaction was produced phenol.(4) Free sugars and free amino acid in konjac flour around non-enzymatic browning were changed. Further free sugars and free amino acid in A. albus flour and A. konjac flour were analyzed by gas chromatography and automatic amino acid analyzer aronud the non-enzymatic browning, it was show that the composition of free sugar in A. albus flour and A. konjac flour were different around non-enzymatic browning, only one kind of glucose in A. albus flour, which concentration is reduced; arabinose and glucose in A. konjac flour which the content of glucose is reduced and the content of arabinose is not changed.The composition of free amino acid in A. albus flour and A. konjac flour were same, there are 16 species of ingredients, the large content of amino acid in A. albus flour is serine,others are glutamic acid, threonine and aspartic acid; the large content of amino acids in A. flour to change is serine, others are alanine, arginine, glutamic acid, leucine, threonine, aspartic acid and lysine.(5) Maillard reaction simulation experiment. Glucose and amino acids are processed Maillard reaction simulation, the greatest strength of browning is lysine, next histidine, other changes are not obvious. Although the content of serine, alanine and arginine are changed greatly in A. albus flour and A. konjac around Maillard reaction, but that the color of three kinds of amino acid accured by Maillard reaction is lighter, so it did not participate in Maillard reaction. The components of Maillard reaction products in Lysine, histidine and glucose are analyzed by gas-mass spectrometry, more ketones, the more content of components is 2,3-dihydro-3,5-dihydroxy-6-methyl-4 (H) pyran-4-ones, there is documentation that the material is one of the characteristics product in Maillard reaction, so Maillard reaction simulation experiment is successful.(6) The components of Maillard reaction products are analyzed by gas-mass spectrometry in A. albus flour and A. albus flour. A. albus flour was analyzed 9 chemical composition which were less species, A. konjac flour was analyzed 91 chemical composition which were more categories, the more contain products in this two kinds of konjac flour is 2,3-dihydro-3,5-dihydroxy-6-methyl-4 (H) pyran-4-ones.5-hydroxymethylfurfural was also analyzed in Maillard reaction products of A. konjac flour, the material is also a middle product of Maillard reaction, therefore, the color of A. albus flour and A. konjac flour were changed because they take place maillard reaction by heat treatment.(7) A. albus flour and A. Konjac flour is identification. Results show that, With the temperature rising, yellow index of A. albus flour and A. konjac flour is increased, more and more color, so white and konjac flour konjac flour to cold storage in order to prevent or slow non-enzymatic brown change occurs, although it can not tell from the sensory A. albus flour and A. konjac flour, but the colors of A. albus flour and A. konjac flour occurred non-enzymatic browning reaction after 105℃heating 4h are difference Large,so easy to identify A. albus flour and A. konjac flour. A. albus flour artificial by mixing different ratios of A. konjac flour is heated by 105℃after 4h,standard color can be broadly identified in A. albus flour mixed with a number of A. konjac flour.