| Rice protein(RP) was widely favored for its high nutrition and low hypoallergenic character. It has been confirmed to have better composing of essential amino acids, high value of BV, and lower irritability as compared with other plant proteins. Unfortunately, over 80% of the protein contained in rice kernels is glutelin, and the solubility of rice protein is very low. So the functional properties of rice protein were poor. The purpose of this paper was to discuss the Maillard reaction between RP and sugar, and to improve the functional properties of the protein by the reaction. The relationship between the improved functional properties and the factors that influence the Maillard reaction was also studied.The rice protein was extracted by alkili. And the RP reacted with sugars by dry-heated Maillard reaction. The aim of this investigation was to find the optimum conditions that can obtain the conjugates with excellent emulsifying properties. The optimal reaction conditions were as follows: RP reacted with dextran in weight ratios of 1:5, at 40oC ,79% relative humidity for 24h. The graft degree of the Pr-D was 29.29%.On the base of dry-heated Maillard reaction, this paper try to improve the functional properties of RP by wet-heated Maillard reaction. The improvement of solubility,emulsifying property of the conjugates combined with graft degree, browning, pH value of the system were studied in order to optimize the reaction conditions. The results shown that Pr reacted with glucose(WR=1:1) at pH11, 90℃water bath for 15min has excellent functional properties. The solubility of Pr-G could reach 90.3% at pH 8. The graft degree of the Pr-G was 34.01%.Then the influence of different pH value and drying methods on the functional properties of RP-glucose conjugate were investigated in this paper. The results shown that the functional properties of Pr-G were all improved under different pH. The solubility and emulsifying stability of Pr-G decreased after drying, however, they were improved for a certain extent compared to protein control. The conjugates obtained from the increasing protein concentration system (4%w/v in protein) still have better functional properties after spray drying.The structure and physico-chemical characteristic of the Pr-G conjugates were analyzed by hydrophobicity, florescence analysis, HPSEC-MALLS-UV-RI combined system, IR and amino acid analysis. The conjugates have the strongest florescence intensity when emission was 347nm and the excitation was 425nm. And florescence intensity sharply increased within the first 10min, then increased slowly with increased time. The result ensured that the Maillard reaction was happened. HPSEC-MALLS-UV-RI combined system was used to measure the molecular weight of the conjugates. Resuts from HPLC shown that the aggradations of RP were changed by Maillard reaction. Before the reaction, the molecular weight of RP was 1.067×106Da. However, the molecular weight of the protein became smaller when the reaction occurred. The molecular weight was 2.44×105Da when reacted for 15 min. The solubility of the protein has been changed and so did the other properties. The information of intermediate from Maillard reaction could be find by HPLC. The amino acid analysis shown that the content of cysteine, lysine, proline and arginine was decreased by glycation. In addition, the surface hydrophobicity decreased with increasing reaction time.
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