不同贮藏方式对双肩玉荷包荔枝氨基酸变化的影响

Changes in Amino Acid Contents of Shuangjianyuhebao Litchi during Different Storage Conditions

采用低温(3-5℃)和气调保鲜(3-6℃、85-95%RH、O2浓度3-5%vol、CO2浓度3-5%vol)两种方式贮藏双肩玉荷包荔枝,通过全自动氨基酸分析仪分析荔枝样品在0-42 d贮藏期果实的氨基酸组分含量变化。结果表明,初期(0 d)荔枝的氨基酸总量为2.93 mg/g,其中主要为γ-氨基丁酸(GABA)、丙氨酸(Ala)和谷氨酰胺(GluNH2)。两种贮藏方式荔枝的氨基酸总量在贮藏前期差异不显著(p>0.05),贮藏至42 d,冷藏样品为2.93 mg/g,气调样品为3.13 mg/g。贮藏期从0-14 d,冷藏和气调样品的GABA含量分别从初始的1.01 mg/g和1.08 mg/g显著增加到1.25mg/g和1.30 mg/g,之后前者的GABA含量出现下降,而后者的GABA含量仍较高,差异达到显著水平(p<0.05)。两种贮藏方式下样品的丙氨酸含量有增加趋势,但差异不显著(p>0.05),谷氨酰胺含量在贮藏7d后显著减少,而谷氨酸含量则在贮藏7-35 d期间显著增加(p>0.05)。

Changes in contents of amino acids of litchi （Litchi chinensis Sonn.） cultivar, Shuangjianyuhebao stored by refi-igcrated storage at 3-5 ℃ and controlled atmosphere （CA） storage （3-5 vol% 02, 3-5 vol% CO2 at 3-5 ℃ and 85-95% RH） for 42 days were analyzed by using an automatic amino acid analyzer. The results showed that the fresh litchi has total amino acid content of 2.93 mg/g with 7-amino-n-butyric acid （GABA）, alanine and glutamine being of the dominant amino acid composition. No significant difference （p〉0.05） in total amino acid content between samples with refi＇igerated storage and CA storage was found in the early storage period. After a 42-day storage, total amino acid contents of the samples by refrigerated storage and CA storage were 2.93 mg/g and 3.13 mg/g, respectively. GABA in samples stored for 14 days by refiigerated and CA storage was increased fi＇om 1.01mg/g and 1.08 mg/g to 1.25 mg/g and 1.30 mg/g, respectively. Then GABA was decreased during refi＇igerated storage, but maintained a stable level during CA storage （/7〈0.05）. Alanine content in sample stored by refiigemted and CA storage showed a little increase （p〉0.05）. During 7-day storages under different conditions, glutamine content was decreased and glutamic acid content was increased （p〈0.05）.