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The Ceramic-pot sealed meat was used to study. Through analyzing the change rules of proteins, fats, micro-organisms, endogenous enzymes, maillard reaction, combined with the changes of volatile compounds and sensory test during the processing and storage, the flavor formation mechanisms of Ceramic-pot sealed meat can preliminary be studied. It can provide a basic theory for improving the traditional technology of Ceramic-pot sealed meat. The main results and conclusions were summarized as follows:(1) After frying no microorganism was detected during the storage of Ceramic-pot sealed meat. This result showed that traditional sealed way could protect the meat from contaminating by the environment’s microorganism.(2) A total of120volatile compounds were detected in Ceramic-pot sealed meat during the processing and storage. Alcohols, aldehydes, ketones, hydrocarbons, amides and esters were the major ingredients, while the relative contents of aldehydes, which were mainly hexanal and2,4-decadienal, amounted highest (64.42%). During the processing, aldehydes, ketones, esters increased notably, while amides were detected. During the storage, the relative contents of alcohols, aldehydes and ketones, decreased overall, whereas hydrocarbons, amides esters and other compounds increased, meanwhile (2E)-2-undecenal, hexyl formate,(Z)-9-octadecenamide and2-pentylfuran were newly generated.(3) Four items of sensory estimation, including colour, morphology, smell and taste were used to estimate Ceramic-pot sealed meat during processing and storage. Results showed that the flavor of Ceramic-pot sealed meat was basically formed after storing for55days. (4) During the curing and hanging phase, the activity of protease and lipase decreased notably (P<0.05). After frying, the activity of protease and lipase turned to zero and the activity could not be detected during storage.(5) The contents of amino-acid nitrogen (AAN), non-protein nitrogen (NPN) and free amino acids (FAA) notably increased (P<0.01) and FAA maximized (219.2mg/100g) at the end of frying, and declined slowly in the prophase and metaphase, and increased again and AAN maximized (0.32%), NPN maximized (0.616%) in the anaphase storage; after high-temperature frying, the protein contents(dry muscle) of sarcoplasmic protein and myofibrillar protein declined to4.18mg/g and4.70mg/g, protein bands more than66KD completely disappeared, and less than16KD largely accumulated. New bands of51KD and42KD came out in the later storage phase of sarcoplasmic protein. The results indicated that the denaturation of protein and proteolysis in Ceramic-pot sealed meat mainly happened during frying, while proteolysis changed very slowly during the curing phase and storage.(6) The acid value of Ceramic-pot sealed meat increased slowly during the curing and hanging phase, decreased significantly during frying (P<0.01), maintained steady during prophase and metaphase of storage and increased again and maximized (1.19mgKOH/kg) in the anaphase storage. Peroxide value and TBA increased gradually during the processing and storage. The content of muscle phospholipid decreased gradually during the processing and storage, especially decreasing from18.14%to9.77%during frying. The content of free fatty acid firstly increased and then decreased during the processing and increased gradually during storage. All these facts showed that fat decomposition was throughout all the processing and storage, and phospholipid was the main substrate. (7) Polyunsaturated fatty acids of phospholipid and free fatty acid, which were mainly linoleic acid (C18:2), were degraded during the processing, whereas the relative contents of alcohols monounsaturated fatty acids in glycerides accounted increased from44.06%to50.14%. The major free fatty acids in glycerides accounted, phospholipid and free fatty acid of mature Ceramic-pot sealed meat were palmitic acid (C16:0), oleic acid (C18:1) and linoleic (C18:2).(8) The content of5-Hydroxymethylfurfural (5-HMF) increased rapidly to6.11mg/kg during frying but decreased to1.13mg/kg after storing for5days. The content of5-HMF stayed steady during prophase and metaphase of storage and increased until anaphase of storage. Its browning degree increased gradually during the processing, especially increasing quickly from0.042to0.14, almost2.09times, during frying. Its browning degree gradually decreased during prophase of storage and then increased significantly (P<0.01) after storing for55days. These showed maillard reaction happened at different degrees during the processing and storage of Ceramic-pot sealed meat.(9) The characteristic flavor of Ceramic-pot sealed meat is mainly engendered by the protein degradation, fat decomposition, maillard and caramelization reaction.
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