预冷结合气调对荷兰豆冷藏期间品质的影响
Effect of pre- cooling combined with controlled atmosphere on quality of Pisum sativum L.during refrigerated storage
-
摘要: 研究了预冷结合气调(CA)对荷兰豆冷藏期间品质的影响。采收的荷兰豆分别在常温下放置0(立即预冷)、6、12 h(对照)后置冷库内以强制通风(1.0±0.5)℃方式预冷至中心温度下降到2℃,于(1±0.5)℃、3%O2+5%CO2+92%N2环境下贮藏30 d。贮藏期间每10 d测定荷兰豆的色泽(a*值),超氧阴离子(O2-·)产生速率,呼吸速率,丙二醛(MDA)、叶绿素、纤维素、还原糖含量,纤维素酶(CEL)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性。结果显示,预冷结合气调贮藏显著抑制了荷兰豆a*值、纤维素含量的上升和叶绿素含量的下降;还原糖含量略高于对照;维持了相对低的呼吸速率、O2-·产生速率和MDA含量;CEL、SOD和POD活性显著高于对照(p<0.05),且立即预冷组优于6 h后预冷组和对照组。以上结果表明,立即预冷结合气调贮藏能有效维持荷兰豆的鲜绿色,延缓纤维化,抑制呼吸作用,提高抗氧化酶类活性,最终维持荷兰豆较好的品质。Abstract: The combined effect of pre- cooling and controlled atmosphere( CA) on quality of Pisum sativum L. was investigated.Pisum sativum L.were precooled in a cold storage to about 2 ℃ after placed at room temperature for 0( immediate pre-cooling),6,12 h( Control),respectively,and then stored for 30 days at( 1 ± 0.5) ℃ with controlled atmosphere( 3% O_2+ 5% CO_2,balance N2).Changes in a*value,O_2~-· production rate,respiration rate,MDA,chlorophyll,cellulose and reducing sugar contents,cellulase( CEL),superoxide dismutase( SOD) and peroxidase( POD) activities were evaluated at intervals of 10 days. The results showed that the immediate pre- cooling combined with CA significantly retarded the increase of a*value and cellulose content and the decline of chlorophyll content,maintained relatively lower respiration rate,O_2~-· production rate and MDA content.Reducing sugar content was slightly higher than the control. The treatment also promoted CEL,SOD and POD activities compared with the control.The present findings indicated that the immediate pre- cooling combined with CA could retard yellowing and fibrosis,inhibit respiration rate,improve antioxidant enzymes activities,and therefore maintain a better quality of Pisum sativum L.