Studies On Rheological Properties And Texture Evaluation Of Jerusalem Artichoke And Pickled Jerusalem Artichoke Tuber

Jerusalem artichoke is a kind of familiar tuber vegetable,and it is usually be used to extract inulin or make pickled vegetable. Jerusalem artichoke has the advantage of high nutrition value and easily growth,so it is semi-wild resource with very important development value. The parameters of rheology and texture are important parameter to evaluate the quality of fruit and vegetable ,they are always primary factors to affects customer to choose fruit and vegetable. So, investigating changes of rheology and texture quality of fruit and vegetable such as Jerusalem artichoke after gathering has very important meaning to dispose and evaluate their quality.With "Jerusalem artichoke and pickled Jerusalem artichoke tuber" as the main objects and texture analyzer as the main instrument, this thesis mainly focuses on the aspects as follows: the "slight deformation" tests such as stress relaxation and creep test,the destructive tests such as puncture test,compression test,shearing test,bending test,tension test,and the simulative test such as TPA (Texture Profile Analysis) test.Different test conditions had been respectively applied to every kind of test in order to get the best test conditions. The results show that speed,time and distance affect the tests differently,and the main influencing factors are different with different measurement. So the test conditions has to be optimized respectively: For Jerusalem artichoke, taking of samples should be in the core region of it and samples should be taken peel out. The probe of P/3 is chosen in the puncture test. The optimal test conditions are as follows: Test speed 0.2～5mm/s,distance > 3mm in the puncture test; Test speed 0.2～4 mm/s in the shearing test; Test speed 0.2～4mm/s,distance > 2mm in the TPA test; Test speed lmm/s,distance 0.5mm,time 60s in the stress relaxation test; Test speed 0.5mm/s,force 3000g,time 60s in the creep test.The trends of rheological and texture properties of Jerusalem artichoke under different storage temperature and Jerusalem artichoke under different storage measure were studied. Meanwhile,sensory assessment was also be made .The results show that ultimately quality of Jerusalem artichoke under different storage temperature is different distinctly. The condition under 1℃is good for keeping its quality;Packing with PE fresh-keeping film or PE fresh-keeping bag is all-right measure for keeping quality of Jerusalem artichoke. Dealing it with CaCl₂ is also a good measure;Changes of texture and rheological properties of Jerusalem artichoke are relational with change of its sensory property and water content in course of storage. Specially,there are good correlation between Crispy,Texture,Greenness (sensory parameters) and NSR, Fracture distance of puncture test, Resilience of TPA test (texture parameters),their R is respectively 0.952,-0.955,0.957.The difference of Jerusalem artichoke and pickled Jerusalem artichoke tuber in texture and rheological properties,and the change of texture properties, rheological properties and sensory property of Jerusalem artichoke and pickled Jerusalem artichoke tuber by heating them up are studied. The results show that the difference between Jerusalem artichoke and Pickled Jerusalem artichoke tuber is notable. The effect of heating them up for their rheological and texture properties is distinct.The nonfigurative texture quality of Jerusalem artichoke and Pickled Jerusalem artichoke tuber is be made embodiment and digital by above research,and handy methods are established for estimating their integrated quality. Sensory estimate is also be made simultaneity. The correlation between sensory estimate and texture analyse will be studied farther .The study provides basis for the using of instrumental analysis instead of sensory estimate in the assessment for texture quality of Jerusalem artichoke and Pickled Jerusalem artichoke tuber.