| Rice residue, the by-product during producing starch sugar, was used to prepare high emulsibility production by two modification methods, including enzymatic hydrolysis and Maillard's reaction. The high emulsibility production was successfully used in microcapsule powder oil.1. Determined the content of rice residue, such as moisture content, ash content, protein, fats, carbohydrate, metal elements and amino acids. It is indicated that rice residue was abundant of protein, metal elements and amino acid, and it was a good raw material for functional foods. Many methods were studied to extract protein in rice residue, the best method was using amylase and cellulose enzymatic hydrolyse carbohydrate after the fats were removed by hexane. By this means, the loss percentage was only 18%, the purified rice residue contained protein 84%, we can call it rice residue protein.2. Investigated effects of papain, alcalase,protamex and flavourzyme to hydrolysis degree, emulsification activity and emulsification stability of enzymatic hydrolyzed rice residues protein. It was clearly found that alcalase 2.4L FG was much better than the other three. The hydrolysis characters of rice residue protein were studied with Alcalase 2.4L FG in light hydrolysis degree and with the results as follows, pH was 9.0, the hydrolytic time was 30min, temperature was 60℃, the substrate concentration was 10 g·100ml-1water, the enzyme concentration was 0.03 mL·g-1 water(the enzyme was diluted to 10% concentration ).According to pH-state, limited enzymatic hydrolyzed rice residues protein with different hydrolysis degree could be prepared by controlling the added NaOH volume. When the volume was 0mL,9mL,18 mL,27 mL,63 mL, the limited enzymatic hydrolyzed rice residues protein with different hydrolysis degree (DH=2.89%,3.89%,4.89%,5.89%,9.89%) could be gotten. In order to record conveniently, DH was recorded as 3,4,5,6,10 instead of DH=2.89% ,3.89 % ,4.89 % ,5.89 % ,9.89 %.3. Emulsification characteristics such as emulsification activities, emulsification stabilities, dissolution characters, surface tension, consideration and granularity gaussian distribution was studied with the Rice Residues Protein DH 3,4,5,6,10 which was limited enzymatic hydrolyzed by Alcalase 2.4L FG It could be easily seen from the investigation result that rice residues protein with limited enzymatic hydrolyzed had much better emulsification characteristics than rice residues protein. And the emulsification activity of the rice residues protein DH 4 was better than sodium casein, but the emulsification stability a little worse than it. In a word, the rice residues protein DH 4 had a very good emulsification characteristic.4.Determined molecular weight distribution of limited enzymatic hydrolyzed rice residues protein with different DH, distribution range was from 80Da to 15KDa. While the hydrolysis degree increasing, more low molecular weight appeared. While DH=10, the molecular weight was mainly at 692Da, the ratio reached 94.76%. Because there were chiefly micromolecule peptide or amino acid in DH10, and lower molecular was with worse flexibility , yet the hydrolysis production of DH10 was with low emulsification properties. The highest emulsification hydrolysis production of DH4 possesed a molecular distribution range with 43.17% at Mw=2233 Da and 50.17% at Mw=441Da.5.The factors such as limited enzymatic hydrolyzed rice residues protein of different DH, different substrate ratio to the malt dextrin, reaction temperature, reaction pH and reaction time which affect the Maillard's reaction kinetics were discussed. Response surface methodology was used to optimize Maillard's reaction factors, in order to get the Maillard conjugation with the highest emulsification activities. The results indicated that: the DH 6, the weight ratio of RRHP to MD 8:1, temperature 58℃, pH 6.5, and reaction time 3 days were the optimum reaction conditions. Within these conditions, the actual emulsification activities value (EAI=0.3170) was higher than sodium casein (EAI=0.2695) .6.The spectra of limited enzymatic hydrolyzed rice residues protein -malt dextrin Maillard conjugation was determined by FTIR spectrometry. The absorption peaks of the spectra were analyzed. Results from the comparison of the three spectra showed the spectra of Maillard conjugation possessed not only amide characteristic absorption peaks in limited enzymatic hydrolyzed rice residues protein, but also C— O-C characteristic absorption peaks in malt dextrin. Some differences in the intensity and the shape of absorption peaks of their FTIR spectra could be found,especially at 3400cm-1, 1660 cm-1 and in the range of 1456-1369 cm-1, which mainly reflected the substituent nature of C=O and O-H. So FTIR spectra could be used for the identification of Maillard conjugation.7.Used the self-made high emulsification activity products, DH4 limited enzymatic hydrolyzed rice residues protein and limited enzymatic hydrolyzed rice residues protein -malt dextrin Maillard conjugation to embed oil for preparing microencapsulation powder oil. It could be told from the results that self-made DH4 limited enzymatic hydrolyzed rice residues protein could be used to substitute sodium casein, when the ratio of DH4 enzymatic hydrolyzed rice residues protein to gum Senegal was 7:3, the microencapsulation production embedding ratio could reach 92.5%, and the production could get to request. But the self-made Maillard conjugation could relatively get a lower embedding ratio 83.3%, when it was combinated with gum Senegal at the ratio of 6:4.
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