| Food superhigh pressure processing technology is used for food sterilization,improvement of food quality and extraction process,and the technology has been studied at home and abroad for many years.According to the results of previous studies,it can be seen that super-high pressure can change the spatial structure of large molecules of food organic compounds and affect the food quality,such as high pressure can make proteins fold and denature.Due to the complexity of large molecular structure of food organics,most of the researches on the structural changes of organic macromolecules under high pressure are studied after the superhigh pressure treatment.In order to explain the inherent law of protein folding and degeneration under high pressure,we try to from the amino acids and peptides,simple at the same time in order to explore the structural change of organic matter under the pressure of the higher law,we use the high pressure in situ Raman spectroscopy under the high pressure of L-serine,L-Aspartate,L-cysteine,L-arginine,L-cysteine and five kinds of amino acids,such as proline,oxidized glutathione and D-galactose and D-lactose,two sugars of eight kinds of common food small molecules structure change of Raman spectroscopy.The main conclusions are as follows:(1)L-serine crystals,respectively between 0.1-1.37 GPa,2.2-2.7 GPa,5.3GPa,6.0GPa,7.46-7.9GPa,10.1-11.0GPa,and 15.5-17.5GPa,etc.have structural phase changes.(2)L-aspartate respectively between 0.55-2.10 GPa,between 0.82-1.09 GPa,GPa of 2.20-2.47,between 3.30-3.58 GPa,between 5.20-6.60 GPa and between 9.40-10.00 GPa between six structural phase transformation in the pressure range.(3)L-cysteine crystals occurred in the four ranges of pressure between 1.78-3.57 GPa,7.78-8.63 GPa,10.9-12.0GPa,16.65-18.1GPa,etc.(4)L-arginine was constructed in the pressure interval between 1.1-1.4GPa,6.0-7.2GPa and 10.6-11.8GPa.The structural phase change between 1.1 and 1.4GPa may be related to the change of crystal structure due to the rearrangement of L-arginine molecules.(5)Proline was structurally phase-transitioned within the pressure ranges of 1.09-1.92 GPa,5.23-6.34 GPa,10.60-12.00 GPa,and 17.20-18.40 GPa,respectively,among which 1.09-1.92 GPa.(6)Oxidized glutathione undergoes a structural phase transition between 6.15 and 6.56 GPa.The structural phase transition may be related to the breakage of the N-H...N hydrogen bond.(7)D-galactose was found between 3.85 and 4.94 GPa,between 7.68-8.73 GPa,13.22-14.89 GPa,16.57-18.17 GPa and 25.66-27.41 GPa.The structural phase change between 3.85 and 4.94 GPa may be related to the lattice vibration of D-galactose.(8)D-lactose had a structural phase change between 0.66-1.63 GPa,4.77-5.83 GPa,11.45-13.20 GPa,and 18.11-19.65 GPa.(9)For oxidized glutathione undergoes and D-lactose,the stability of their structures under high pressure is higher than that of their small molecules under high pressure.In addition to serine and cysteine,the experimental subjects selected in this thesis were studied by others.At the same time,the high-pressure Raman technique was first introduced into the food field.From the perspective of food processing,the structural changes of food molecules were studied for food performance.Impact.Therefore,this dissertation not only enriches the database of amino acid molecular structure phase transition under high pressure,but also provides a feasible solution for the study of food under high pressure. |
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