Study On Flavor Changes During Maillard Reaction Of Chicken Bone Extracts Hydrojysate And Safety Assessment

Chicken bone contains plenty of protein, and animal protein is a kind of precious resources for partof the developing countries. At the same time, abandoned chicken bone can cause great influence to theenvironment.. Therefore abandoned bone resources transformed into animal protein resource humansneed, not only is a recycling of resources, but also can reduce environmental pollution. This paper isbased on chicken bone as raw material. Maillard reaction makings were obtained by hot-pressingextraction and enzymolysis, and the process was optimized. The product flavor of Maillard reactionproducts (MRP) from chicken bone and its hydrolysate were compared. The changes of compoundsduring the process were analyzed, studying the changing rule of the flavor and taste combined E-noseand E-tongue. The safety evaluation of MRP was studyed using Sprague-Dawley rats.Sensory evaluation was carried out according to Chinese national standard (GB/T16861-1997Sensory Evaluation). Combining with fuzzy mathematical evaluation method, the optimum process ofthe Maillard reaction was determined. The parameters is as follow: the value of pH is7.0, the reactiontemperature is105℃, reaction time is90min, the additions of D-Xylose, cysteine and thiamine are all2%.The flavor characteristics and difference of Maillard Reaction Productions from chicken boneextract (MRPs1) and Maillard Reaction Productions from the enzymatic hydrolysate of chicken boneextract (MRPs2) were analyzed. The non-volatile flavors as follow: total free amino acid is1.4mg/g(MRPs1) and8.1mg/g (MRPs2), freshness amino acid are respectively0.37mg/g (MRPs1) and0.71mg/g (MRPs2); the content of oligopeptide is11.37mg/ml (MRPs1) and14.03mg/ml (MRPs2); thecontents of AMP, GMP, IMP were70.12,185.01,415.60μg/mL (MRPs1) and57.46、186.81、475.56μg/ml (MRPs2); the value of MSG is3.06and6.77gMSG/100g fresh weight. Forty andforty-five volatile compounds were identified in the two kind of MRPs. Aldehyde and ketone compoundswere respectively15.17and22.57%, and heterocyclic compounds were respectively39.43and42.86%in kind ofMRPs. The intensity volatile flavour in MRPs2was stronger than that in MRPs1. Therefore, whetherfrom the volatile flavor or volatile flavor, the product gets more full-bodied aroma after enzymolysis.The variation of flavor and taste was studyed by chicken bone extracts hydrolysate during Maillardreaction. Most amino acids are down after rising first, and reached the maximum in60min. Flavoramino acid such as aspartic acid shows the tendency of increase significantly (p <0.05) and glutamate isno significant change. Sweet amino acids continued to increase during the reaction. Bitter amino acidshad significant rise in the60min and great decrease after60min. The nucleotides presents a trend ofgradual decline, mainly resulted from a degradation of the nucleotides. And EUC had no significance.The results using TS-5000Z system to evaluate the taste was consistent with physical and chemicalindex. At the same time, the E-Nose and SPME/GC-MS combined with internal standard method wereused for the determination of volatile flavor of the product. In PCA of electronic nose, the first principalcomponent (PC1) and the second principal component (PC2) contribution rate were95.44%and2.71%,respectively. The flavor produced bigger difference as the reaction, but after the reaction to60min, they have overlap on PC1, and flavor characteristics have more in common. At the same time, they weredetected21,25,39,51compounds by SPME/GC-MS, the contents of alcohols, acids, and estercompounds increased firstly and decreased laterly. But the contents of aldehyde, ketone and heterocycliccompounds were rising in the whole process.The safty of MRP by chicken bone extract hydrolysate was studyed. A certain gradient of MRP bychicken bone hydrolysate was added in the diet of SD rats. In the process of3months, no abnormalitywas discovered, such as the colour, drinking water, feeding, mental state. There was no significantdifferences in body weight and food intake between experimental group and blank group. In hematology,MCHC of high, middle dose group had significant difference compared with the blank group (p<0.05).In blood biochemical indicators, ALAT of high, middle dose group compared with the blank groupdecreased significantly (P <0.05). And no obvious pathological changes were detected in SD rat organs.Therefore, the experimental dose of MRP by chicken bone extract hydrolysate will not harm the SD rats,and it is safe.