Effects Of Packaging Materials On The Quality Of Rice Ancd Millet During Storage

Rice and millet are important food crops in China,they are the staple food in our daily life,they provide essential nutrients such as carbohydrates,water and protein to our daily lives.The nutrients in rice and millet content is reduced during storage,and sensory quality,cooking quality decreased.In this paper,by studying the changes of rice and millet,in the different storage conditions and different packaging materials,provide the basis for the storage of rice and milletIn this experiment,use Dandong rice and Chaoyang millet as material,respectively,PVDC packaging materials and Composite bag(polypropylene/polyethylene/nylon)packaging materials vacuum packaging,storage at room temperature and constant temperature and humidity(Temperature 38 degrees,humidity 85%)and measured.Comparison of changes in the composition of rice and millet,to determine a better rice and millet storage program.The results are as follows:Moisture content of rice,water absorption of rice,soluble solids content of rice soup and pH value of rice soup decreased.Starch iodine value of rice soup,water activity of rice,amylose content of rice,reducing sugar,fatty acid value increased.Amylase and lipase showed a tendency to decrease first and then decrease.The water content,reducing sugar,amylose,fatty acid valueis an important indicator of the quality of rice.Under the two storage conditions,the water content of rice in PVDC packaged rice was declines quickly than that in the composite bag,fatty acid and reducing sugar increased rapidly,there was no significant difference between lipase and amylase.Room temperature PVDC packaging materials of rice water content decreased to 10.32%in 300 days,composite packaging bags of rice water content dropped to 10.32%in 210 days The content of reducing sugar in PVDC packaging was increased from 1.6%to 2.7%in 300 days,and the compound bag increased from 1.6%to 2.7%in the 210 days.Under the condition of constant temperature and humidity,PVDC material of rice water content dropped to 10.33%in 56 days,and the compound bag rice dropped to 10.01%in 56 days.The fatty acid value of PVDC material increased to 31.7 and the compound bag increased to 35.3 in 56 days.Room temperature and constant temperature and humidity conditions,PVDC material is good for rice storage.At room temperature PVDC material water content of rice reached 10.33%,constant temperature and humidity PVDC material moisture content of rice reached 10.33%.Room temperature conditions are more conducive to the storage of rice.The ?E of rice chroma is increasing,The ?E is no difference of room temperature conditions two kinds of packaging materials rice in 360 days.Constant temperature and humidity conditions,the compound bag of rice 35 days to produce differences,PVDC material of rice did not show any differences.At room temperature,PVDC bag sensory score reach to 8.1 points in 170 days,composite bag reach to 8.1 points in 130 days.Constant temperature and humidity conditions PVDC material to 6.8 in 56 days points at this time sensory quality evaluation for the general,Composite bag 42 days to 5.8 points at this time sensory quality evaluation is bad.The first major component of the electronic nose is W5S,the nitrogen oxides,Different packaging materials under different storage conditions of rice nitroxides increased with storage time.Millet at room temperature due to shorter storage time,millet indicators of the slow changes and quality changes are not obvious,But the storage of 60 days millet PVDC packaging indicators are better than composite packaging materials.The fatty acid value of PVDC bag millet increased from 73.7 to 93.1,and the fatty acid value of compound bag millet increased from 73.7 to 102.7 in 56 days.Under constant temperature and humidity conditions,the rate of change of each index was significantly faster than room temperature.The temperature and humidity have great influence on the storage quality of rice and millet,In high temperature and humidity of the southern region high barrier material is more suitable for storage such as PVDC.