The Prepartion Of The Beef Flavor And The Research On The Intermediates Of Maillard Reaction-Alpha-Dicarbonyl Compounds

In order to prepare the quality beef flavor and elucidate Maillard reaction (MR) mechanismand formation pathway of flavor, the optimal process of the beef flavor were optimized by singlefactor and orthogonal experiment. The meat-like MR model systems of glucose/ribose/L-cysteine were builded, which flavor compounds were analyzed by GC-MS under differentconditions (thiaime concentration, pH, temperature, reaction time). The Alpha-dicarbonylcompounds (α-DCC) of ribose/L-cysteine MR model system was trapped witho-phenylenediamine (OPD), separated and identified by HPLC and LC/ESI-MS/MS underdifferent conditions (pH, temperature and reaction time). Results are summarized as following.1. The optimal recipe of beef flavor is100g beef protein hydrolysates,0.3M ribose,4:3ratio of ribose and L-cysteine,0.05M thiamine,0.09M glutamate,1.5%tallow,1%yeast,0.1ganiseed powder,0.06g cassia powder,0.06g onion powder and1g salt. The optimal reactioncondition is60min,115℃, pH5.6.2. The flavor compounds are mainly meat-like sulfur-containing compounds in ribosesystem, and roasted flavor compounds in glucose system. After adding thiaime,2-Methyl-3-furanthiol,2-Thiophenethiol and4-methyl-5-thiazoleethanol increased, whichcontribute to the beef-like flavor.3. When the concentration of thiamine increased, the yeilds of key flavor compoundsincreased. The flavor compounds can be divided into acid, weakly acid and alkaline compoundsaccording to different effects of pH. Most of the flavor compounds increased with increasingtemperature and reaction time.4. Eight kinds of α-DCC were identified in the ribose/L-cysteine MR system.N-2,3-dioxopentyl-L-cysteine is a newly discovered substance. The pH and temperature were themajor factors affected the quantity and quality of α-DCC. The pathway of α-DCC under differentconditions was proposed for the MR mechanism.5. The kinetic parameters were obtained after fitting kinetic equations of α-DCC.6. The relationship of the flavor compounds and α-DCC was bulided. Controlling pH andtemperature could influence the yields and components of α-DCC and subsequently control theformation of flavor compounds.