Study On The Preparation Of Meat-like Flavors By Maillard Reaction Of Gluten Hydrolysates

Glutens are rich in nutrition with comprehensive amino acids and high content of protein.They are the modest raw materials for food processing because of their functional properties.Application of gluten hydrolysates in meat-like flavors is important for developing newproducts and provides new ideas for deep processing of gluten in food processing areas.Firstly, seven commercial proteases were evaluated for gluten hydrolysis. Compared toothers, the Alcalase had a higher hydrolysis rate and its hydrolysates could generate richflavors of meat-like. So Alcalase was selected to be the enzyme that hydrolyzes gluten. Bysingle factor and response surface experiments, the hydrolysis conditions were optimized asfollows: pH7.5, reaction time180min, reaction temperature60℃, substract concentration8g/100mL, E/S0.024AU/g.Secondly, the character of Maillards Reaction Products (MRPs) by gluten hydrolysateswith a certain hydrolysis time was analyzed, and the relationship between MRPs of glutenhydrolysates and degree of hydrolysis was explored. An electronic nose (E-nose) was used toanalyze MRPs obtained by gluten hydrolysates and reducing sugars. The results showed thatwhen the hydrolysis time was from120to180min, the flavors of MRPs were relativelysimilar and difficult to be discriminated. A high correlation between electronic nose outputsignal and sensory evaluation score was found. The flavor compounds obtained by Maillardreaction of gluten hydrolysates and glucose were analyzed by SPME-GC-MS.87flavors wereidentified including pyrazines, furans, sulfur compounds, aldehydes, ketones, alcohols andphenols etc. Heterocyclic compounds contens of the MRPs of120to180min hydrolysedgluten were shown to be the highest. The degree of hydrolysis and MRPs of glutenhydrolysates were closely related.Thirdly, debittering of gluten hydrolysates using Flavourzyme，Promatex and Alcalasewas studied. It was showed that complexed enzymatic hydrolysation was better than singleenzymatic hydrolysation. The more Flavourzyme was used, the weaker was the bitternesstasted. Gluten was hydrolyzed for60min using Alcalase (0.024AU/g) and the crudehydrolysates was obtained. Then Flavourzyme (100LAPU/g) was added into the crudehydrolysates and reacted for60min. on this condition, debittering effect got best.Fourthly, the optimum conditions of Mallard reation of gluten hydrolysates werediscussed by sensory evalution of Friedman sort. Results showed that the best conditions were:gluten hydrolysates10.0g, glucose3.0g, xylose1.0g, L-cysteine0.4g, VB10.4g, reactiontime60min, reaction temperature120℃, intial reaction pH6.0. Under this condition, meat-like flavors were rich and full.Finally, flavors by Maillard reaction of gluten hydrolysates were analyzed. The E-nosewas used to study MRPs with different conditions. Results showed that E-nose candiscriminate MRPs with different conditions. The flavor compounds obtained by Maillardreaction of gluten hydrolysates and glucose were analyzed by SPME-GC-MS. Based onlibrary searching,64flavors were identified including pyrazines, furans, sulfur compounds,aldehydes, ketones, alcohols and phenols etc.33flavors content of heterocyclic compoundswas about56.26%.