【摘要】：論文采用射頻為主要熱源、輔以熱風對流的方式,研究了不同加熱速率下,不同初始含水率玉米種子的射頻-熱風聯(lián)合干燥動力學及品質,并與不同溫度與緩蘇頻率下玉米種子的熱風緩蘇干燥動力學及品質進行對比。主要研究結論如下:(1)緩蘇處理可以提高下一階段熱風干燥速率,且緩蘇頻率與熱風溫度越高,干燥總時間越短。隨著緩蘇頻率下降、熱風溫度升高,玉米種子綜合品質下降;但熱風干燥10min后緩蘇時,玉米種子發(fā)芽率和脫氫酶活性均劣于干燥20min后緩蘇,說明緩蘇頻率過快易對種胚造成損傷。基于干燥動力學及品質綜合評分結果,熱風干燥20min后緩蘇、熱風溫度40℃為熱風干燥最優(yōu)工藝。(2)玉米種子射頻-熱風聯(lián)合干燥可顯著提高干燥速率。相同的玉米初始含水率下,隨著極板間距的減小,干燥速率加快,玉米品質綜合評分下降;相同極板間距下,玉米初始含水率越高,越有利于保持較好的綜合品質。玉米初始含水率越低,其在射頻-熱風聯(lián)合干燥初期的干燥速率越高,但射頻對其結構的破壞也越大,因此,干燥后期,其干燥速率越慢。基于干燥速率及品質綜合評分結果,玉米初始含水率29.21%、極板間距160mm為射頻-熱風聯(lián)合干燥最優(yōu)工藝。(3)射頻-熱風聯(lián)合干燥裝載量是熱風干燥的3倍,但其干燥時間僅為熱風緩蘇干燥的1/3。與應力損傷、種子活力相關的指標(除發(fā)芽率外)明顯優(yōu)于熱風干燥;由于射頻-熱風聯(lián)合干燥下物料溫度略高于熱風干燥,其與溫度緊密相關的營養(yǎng)成分指標略遜于熱風干燥樣品,但差異不顯著。經射頻-熱風聯(lián)合干燥,玉米種子脫氫酶活性更高,但發(fā)芽率明顯低于熱風干燥樣品,破休眠試驗結果表明,其原因可能是射頻處理引起了種子休眠現(xiàn)象。
[Abstract]:In this paper, the radiofrequency (RF) was used as the main heat source and the hot air convection was used to study the drying kinetics and quality of maize seeds with different initial moisture content under different heating rates. The drying kinetics and quality of maize seeds under different temperature and frequency were compared. The main conclusions are as follows: (1) the drying rate of hot air in the next stage can be increased by the gentle Su treatment, and the higher the frequency and the temperature of the hot air, the shorter the total drying time. The comprehensive quality of maize seeds decreased with the decrease of the frequency and the temperature of hot air, but the germination rate and dehydrogenase activity of maize seeds were lower than those of dry 20min, but the germination rate and dehydrogenase activity of maize seeds were lower than those of dry 20min, but the germination rate and dehydrogenase activity of maize seeds decreased after drying 10min. The results showed that the frequency of slow sucrose was too fast and easy to cause damage to embryo. Based on the results of drying kinetics and comprehensive quality score, the optimum drying process was hot air drying after 20min drying with hot air temperature of 40 鈩，

本文編號：2130419