Studies On The Relevance Between Physicochemical Properties And Sensory Quality Of White Sufu

The companies’ survival and development are directly affected by the product quality.There are more or less differences of the texture and flavours among different brands becauseof the complexity technology and specificity environment. The quality of some brands ismuch better than others in the market. To identify the reasons of differences, providing newways to improve and enhance the sufu quality, the differences of four commercially whitesufu brands were studied.The sensory and physical proterty differences of four brands were studied. Resultsshowed that, the sensory result of texture is most significant, the texture of LF and LP weremuch better than GH and MX, there were more softness and smothy. There were significantlydifference of hardness, adhesiveness, gumminess and chewiness of LF, LP compared withanother two brands, especially between LF and GH. The order of apparent viscosity wereLF<LP<MX<GH. A loose uniform spong-like structure was showed in the microstructure ofLF, whereas a dense granular structure was showed in MX. The microstructure of GH and LPwere similar, both containing greater holes.The chemical compositions and the hydrolysis of protein and oil were studied.Speculated that the physical differences of four brands were mainly caused by proteolysis,and the difference of fat globule gathered morphological caused by oil content and oilhydrolysis also had an effect on microstructure to some extent.The effects of proteolysis and oil content on the physicals were studied on simulatedconditions. Results demonstrated that, the formation of cheese-like texture was not relevant tothe restriction sites. The change of hardness, adhesiveness, gumminess, chewiness andformation of loose, uniform microstructure were mainly caused by protelysis. The addition orincreasing of oil promoted the hydrolysis of protein, and on the other hand reduced thehardness, gumminess, chewiness, apparent viscosity and increased the adhesiveness.Compared to the samples without oil, the oil containing samples had greater holes. Resultsconfirmed that the physical differences among four brands were mainly caused by proteolysis,while the oil played a secondary effect.The volatie flavour compounds of four brands were determined by HS-SPME combinedwith GC-MS. A total of109flavour compounds were determined in four brands and only19the same.60,57,45,55volatiles were identified in GH, LF, LP and MX, separately; theseshowed clearly that there were big differences of volatiles among four brands. The volatilesdifferences in four brands showed that there were different flavours metabolic converting enzymes existed in different brands, which caused by different Microorganisms existed ineach manfufacture environmental.