| The carrot originally produces in west Asia, for two years growth-herb's root vegetable class plant, and its cultivation history is above 2000 years. Carrot is a prevalent vegetable which has crisp quality, dainty sapor and ample nutrition.It has very highly report in world and be regarded as the best of vegetable because of it's beautiful colour, delicate and excessive juice. Li Shizheng in china had praised it as "Vegetable's King",and it alse had been named as "Ersatz Panax".Its whole body is all valuable, and has very high nutritional value and very good medical function..The carrot is an organic living plant, each physiological metabolism activity still is carrying on in stores and Shelf-life time, and reological property and texture also unceasingly chang along with it. But reological property and texture also has the closerelation, therefore studing reological property and texture changes has the positive sense regarding the carrot texture evaluation and the quality research.The paper uses the TA-XT2i Natural Meter to reological test and texture evaluation on the fresh carrot,salting carrot and pickling carrot.mainly includes: The basically reological test and the parameter optimization; The reological property otherness research;The texture forecast of Shelf-life carrot; Tha reological property and texture evaluation of alting carrot; The texture characteristic research on pickling carrot..The test method and parameter have a very tremendousinfluence to test result.using different distortion quantity, distortion speed, pokes and time and so on ,the identical experiment will have difference, and different test method and parameter will be choose in the tests of different goal. In order to enable the test result to have the commeasurability and theuniformity, wo optimize the test parameter before the experiment, the conclusion is: The best test parameter of loading-unloading test is P100poke, distortion quantity 2mm,distortion speed 1mm/s; The stress-relaxation test is P5 poke, distortion quantity2mm, distortion speed2mm/s, maintenance time20s, best reological model is Maxwell model with three Elements and the experience modelⅡ; The creep test is P5poke, load20N, creep time40s, speed1．0mm/s, best model is four parts five parameters model; The TPAtest is P100 pokes, distortion 50%, speed lmm/s, resident time 4s.TakingΦ10×10 (diameter10mm,high10mm) circular cylinder test specimen from different spot (crown,middle,base),different organization (fruit,pulp,core),different direction (crosswise,longitudinal).Carring on the Loading-unloading test, through destruction stress, breaking strain,young's modulus and destruction,wo can found carrot have compactness difference;Carring on the stress-relaxation test, through hardness Fmax, rigidity K, compression merit A, elastic D, balance elasticity coefficient E0,decay elasticity coefficientE1, damping body viscosity coefficient and relaxing time T to attribute carrot have relaxation difference; Carring on the creep test, attributes change difference by creep deformation, wo know creep difference is not very obvious, and not give consideration;Carring on the PTA text, through hardness F1,elasticity, cohesion, chews,hardness F2 and reply six parameters, wo know carrot have TPA difference.A different Shelf-life time causes the reological property difference in different parts, different organizations and different directions, which displays each TPA test curve is not the same, four TPA parameter hardness,elasticity,cohesion and chew have obvious difference, assumes the relevant change, to explain the Shelf-life carrot has TPA difference. cohesion assumes elasticity with minus correlation, but other parameters is plus correlation.Chews has high correlation with other three parameters, occupies the leadership in the four parameters, and it is regarded as the system " Characteristic Factor", so indicated the chewing change can attribute texture change of Shelf-life carrot.Taking "Characteristic Factor"chews as the target,wo can establish texture changepessimistic model GM (1,1) of carrot core and pulp,which is X(K+1)果心(2) = (46．869-45．5013) e-1．4766K +45．5013,X(K+1)果肉(2) = (130．25-172．6964) e-1．4743K+172．6964。And after theconfirmation, the pulp model doesn't conform to the requirement, but the core model conforms to the general requirement, therefore wo can use core GM (1,1) to establish forecastthe model, which to carry on the very good forecast to texture change of Shelf-life carrot..From optimizating, the best compression text parameter of salting carrot is P5 poke, compression quantity 3mm,speed 2mm/s; The shear test is special-purpose installment,double edge cutting edge poke,distortion quantity 3mm, speed 3mm/s. The longitudinal sample of different temperatures (10℃,20℃,100℃),different spots(crown,middle,base),different organizations (pulp,core) indicated that, salting carrot has the compression characteristic difference, and has caused its texture difference.And the change of hardness F, lag loses A, elastic D and rigidity K is not very obvious,but has obvious regularity in organization, displaying the value of core is bigger than pulp.The biggest compression forces of core must be bigger than the same pulp under 20℃. and present the regular change.Other different temperatures test curves are different, but presents regularity. The comparative and analysis of cuts most vigorously Fmax, peak area S, modulus G and energy E four parameter to indicate salting carrot exists cuts characteristic difference. The relevant analyses of reduces four parameters and cuts fou rparameters to obtain, the same and different temperature also has different parameter relevance, and presents regular change, manifests different preserve temperature to have different influence, causes different rheological property and texture.Optimizing best test condition is P100 poke, compression 90%, speed 2mm/s, resident time 4s. When compresses is 90%, the phenomenon appears obviously in the TPA experiment test curve submits, which can express well the sauce pickling-carrot's brittle value and attribute it's brittleness.Wo carries on the TPA experiment to pickling carrot of two different habitats(Zhenjiang Hengshun, Yangzhou Sihe), three different productive times (2005．10．11, 2006．6．19, 2006．8．29) . Through comparativing and analysising hardness F1, elasticity, cohesion, chews,hardness F2 and the reply six TPA parameters, wo know that time has extremely remarkably affects to various parameters, and variety also influential, but the influence isrespectively different. Along with the change of pickling time,the carrot rheological property and texture also changes, which displays for its TPA parameter regular change. The relevance in various parameters has certain difference, but the correlation is not high, and only hardness F1 and hardness F2 is remarkably correlate, others are not remarkable.Hardness F1 and hardness F2 has minus correlation with elasticity and cohesion, but has plus correlation with chews. The elasticity, cohesion and chews are the plus general correlation. The pickling carrot of different habitat also display different regulary rheological property and texture, which indicates the different pickling carrot has different rheological property and texture, and this difference can be used to instruct factory's production practice and consumer's shopping choice.
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