| The components of potato harvested in Neimeng Province were analyzed. The key factors influencing potato puree's quality during manufacturing, such as cooking, potato mash making and storage, were studied, which would be important to produce high quality potato puree. Meanwhile the system of potato puree's quality assessment was established. Finally we got the best formula of garlic-flavored potato puree.Cooking and potato mash making both influenced the potato cell structure and then influenced the final production quality. The best cook time, about 40min, was determined by using SEM images, Descriptive Sensory Analysis(DSA) and Texture Profile Analysis(TPA), respectively. To avoid potato cell suffering over-shear and be broken up, extrusion method was used to make potato mash.Through researching the influence of emulsifiers, wheat starch, potato starch and granules on the texture properties and sensory attributes, the best emulsifiers formula of 1.00%GMS and 0.10%SE was established. 2.5% potato starch was added to potato mash to make the final product's solid content above 20%, while the firmness of potato puree was about 100N and the cohesiveness was about 0.600.Under conservation, the factors which influenced potato puree's quality were studied carefully. With the use of dynamic rheometer, this part of research was aimed at rheological properties of potato puree subjected to 0,1,2,3,4,5 and 6 freeze-thaw cycles. Rheological data from dynamic rheometer indicated that, with frequency and temperature changing, the effect of freeze-thaw cycles on the elastic modulus(G′),viscous modulus(G″),complex dynamic modulus (G*) and phase angle (δ) of potato puree is significant. It could be concluded from syneresis results that either the initial manufacturing process or the freeze-thaw cycles, or both, caused major structural damage to the morphological components of potato puree. As the number of freeze-thaw cycles increase, the extent of syneresis in potato puree was increased. Unexpectedly, syneresis after six cycles was similar to that of samples not subjected to cycles, maybe six successive cycles led to the creation of a coarsely aggregated structure in potato puree.The flavor of fresh potato puree and potato puree stored at 4℃for 1d were determined by Head Space Solid Phase Micro-Extraction (HS-SPME) and Gas Chromatography-Mass Spectroscopy(GC-MS), Simultaneous Distillation Extraction (SDE) and GC-MS. Aroma compounds were adsorbed and concentrated directly on the fiber in SPME procedure, so that not changed at all. As a result, the SPME experimental result s could represent the volatile flavor component s of raw potato puree. Two hours high temperature cooking with SDE procedure produced more compounds, which represented to cooked potato puree.The firmness and cohesiveness of potato puree were determined by sensory and instrumental analyses, which had good linear correlations. It's feasible that using both textural analysis and sensory analysis to determine the quality of potato puree.Through analyses of sensory index, physical and chemical index, and microorganism index, meanwhile on the basis of experiments and some national standards, the quality evaluating indicator of potato puree was initially fixed.The best formula of garlic-flavored potato puree was potato mashes60.3%, water27.0%, potato starch2.5%, GMS1.0%, SE0.1%, butter7.5%,chicken power0.5%, garlic power0.45%, salt0.4%, and sugar0.2%。...
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