Study On Rheological Properties Evaluation System Of Instant Corn

Corn is a nutritious food. Instant corn is the fresh corn which use of modern food processing technology and vacuum flexible packaging technology to produce. The nutritional value of instant corn is better than corn and products. Instant corn is called "green food", "gold food", "longevity food", "a new nutrition and health food", also be seen as "a fashion and convenience food" by many people. So majority consumers favor instant corn. But, the main method rheological evaluate of instant corn is sensory evaluation. The standard is misty and there is no clear, objective, scientific and quantitative criteria in our country. The research on rheological evaluate of instant corn is few report in foreign. The aim of this thesis was to study the texture evaluation of instant corn by TA-XT. And establish a scientific and objective rheological evaluation system of instant corn.Using Sky-scenery "sticky one" corn and "Jingke waxy" corn as mails in this study. Corn was divided into one, two, three level by maturity automated grading system. The texture of different maturity corn was studied by mechanical test methods, sensory evaluation methods and chemical method, also the different of indexes between different varieties corn and different maturity corn was studied. The correlation of indexes was analyzed by mechanical test, sensory evaluation, and chemical method for instant corn. Find out the key indicators that influence consumer acceptance. Established regression equation what mechanical test replace sensory evaluation on instant com texture. The main conclusions are as follows.1. Using Sky-scenery "sticky one" corn as main material, using Test Analyzer to TPA test, and analyzing the differences. The results showed that:different parts of the grain texture indicators were significantly different at level (p<0.05)2. Optimization of texture tests show that:different test conditions on the instant corn texture the results of mechanical tests have significant impact. By screening, determine the best mechanical testing methods and conditions of instant com texture:(1) P2 probe was used in puncture test, and test parameters were:before the test speed is 1.0mm/s, 1.0mm/s test speed, test end speed is 1.5mm/s,10mm puncture depth, start force is 5g, curve for the recording is target. (2) HDP/VP probe was used in optimum test, and test parameters were:0.5 mm/s test speed,80% compression, start force is 5g, curve for the recording is target. (3) The robe of TPA test is P36R, test parameters were:before the test speed is 1.5mm/s, 1.0mm/s test speed, test end speed is 1.0mm/s,70% compression.3. Using Sky-scenery "sticky one" com and "Jingke waxy" corn as materials. Differences of sensory index, physical and chemical indicators and texture index for different varieties and maturity corn. The results showed that:There were significant differences between the various indicators at level (p<0.05)4. Correlation analysis between sensory indexes, physical and chemical indicators and test indicators of the mechanical texture of instant corn showed that:there were good correlation between sensory indicators and texture indicators, sensory indicators and Physical and Chemical Indicators, Physical and Chemical Indicators and texture indicators. 5. Regression equation was established and verified that:in addition to color and flavor can not be predicted by mechanical test indicators, other indicators of sensory evaluation, for example, hardness, adhesiveness, fracturability, chewiness, springiness and overall acceptability can be predicted well all by mechanical test indicators, and well as the prediction model.This study shows that:rheological properties evaluation of instant corn can use the method of sensory evaluation and Mechanical test combination. The results of this assessment are more objective and accurate. The results of this study supply a powerful foundation for the objective evaluation method creation, quality control and detection of instant corn.