摘要
为探究以糖液为介质的猕猴桃果块品质特性,对比、分析热烫预处理和脉冲超声预处理对猕猴桃果块组织和糖液特性的影响。以猕猴桃为试材,蔗糖溶液为渗透液,采用热烫、脉冲超声(单频超声、双频超声、三频超声)对猕猴桃果块进行渗透脱水预处理,之后置于蔗糖溶液中。结果表明,渗透脱水24 h后,猕猴桃果块的可溶性固形物含量显著增加。质构结果分析表明,热烫预处理组表现出最低的硬度(6.22 N);随脉冲超声频率的增加,猕猴桃果块的(硬度、咀嚼性、回复性、弹性、凝聚性)均呈先升高后降低的趋势,最大值(分别为8.18 N,136.01 N,6.35%,68.35%,0.24)均出现在双频超声预处理组。电学特性分析表明,热烫预处理组因细胞结构破坏严重,故果块阻抗值和电抗值显著降低;而脉冲超声预处理因大量糖分子的渗入,增加了带电离子运动的阻力,故使阻抗值和电抗值随频率的增加而显著增加。色泽分析表明,热烫预处理使猕猴桃组织中叶绿素等色素物质大幅度降解,而出现最高的L*值(68.53)和a*值(2.10);随超声频率的增加,L*值和a*值则呈降低趋势。电子鼻试验结果表明,对照组与脉冲超声预处理组的挥发性成分差异小,表明脉冲超声对猕猴桃风味物质无显著影响。分析糖液特性发现,基于渗透脱水过程中的传质现象,糖液浊度和电导率增加;最大的渗透压(1 482.33 m Osm/L)和表观黏度(367.60 mPa·s)出现在热烫预处理组,其次为双频超声预处理组。猕猴桃果块中色素类物质大量降解渗出,使糖液色泽发生改变,其中热烫预处理组的变化最为显著,这与猕猴桃果块色泽变化一致。综上,双频超声预处理有助于以糖液为介质的猕猴桃果块的品质保持。
In order to analysis the quality formation of kiwifruit chunks within sugar solution as medium,effects of blanching pretreatment and pulsed ultrasonic pretreatment on kiwifruit tissue and properties of sugar solution were researched.The kiwifruit was used as the test material and the sucrose solution was used as the permeate solution,and the kiwifruit fruit pieces were pretreated with permeation and dehydration by blanching and pulsed ultrasound(single pulsed ultrasonic,dual pulsed ultrasonic,and three pulsed ultrasonic),and then placed in the sucrose solution.Results showed that total soluble solid(TSS)of kiwifruit chunks were significantly increased after osmotic dehydration for 24 h.Texture analysis indicated that the lowest hardness(6.22 N)were observed in blanching pretreatment group.Additionally,with the increase in ultrasound frequency,the hardness,chewiness,resilience,springiness,and cohesivenwere first increased and then decreased,meanwhile,the highest values(8.18 N,136.01 N,6.35%,68.35%,0.24,respectively)were all found in the dual frequency ultrasound pretreatment group.Results of electrical characteristics illustrated that when subjected to blanching pretreatment,the impedance and reactance of kiwifruit were significantly declined owning to the extreme damaged cell structure. However, with the inflation of sucrose molecule during OD, the movement of charged particles were inhibited resulted in the increased impedance and reactance accompanied with the increased frequency. L* value and a* value were selected as the evaluated indictors for color analysis of kiwifruit chunks. The highest L* value (68.53) and a* value (2.10) were both obtained in blanching pretreatment group because of the pronounced chlorophyll degradation resulted from blanching treatment. With the increase in ultrasonic frequency, L* value and a* value of kiwifruit chunks were significantly decreased. Results of electronic nose depicted that, only small differences in volatile components between control group and pulsed ultrasonic pretreatment group, which indicated the little effect of pulsed ultrasonic pretreatment on flavor quality of kiwifruit. Furthermore, the quality properties of sucrose solution were studied. Based on the mass transfer during OD processing, the turbidity and conductivity of sucrose solution were significantly increased. Besides, the biggest osmotic pressure (1 482.33 mOsm/L) and apparent viscosity (367.60 mPa·s) was obtained in blanching pretreatment group, followed by the dural pulsed ultrasonic pretreatment group. Due to the pigment degradation, the color changes in sucrose solution were observed, in which blanching pretreatment group showed the most one. This was consistent with the color changes in kiwifruit chunks. Therefore, the dual pulsed ultrasonic pretreatment was benefit for improving the quality properties of kiwifruit chunks with sucrose solution as the medium.
作者
李淑娟
吕健
毕金峰
王凤昭
王静萱
LI Shujuan;LÜJian;BI Jinfeng;WANG Fengzhao;WANG Jingxuan(College of Food Science and Engineering,Qingdao Agricultural University,Qingdao 266109,Shandong;Key Laboratory of Agro-products Processing,Ministry of Agriculture and Rural Affairs,Institute of Food Science and Technology,Chinese Academy of Agricultural Sciences,Beijing 100193;Shandong Technology Innovation Center of Special Food,Qingdao 266109,Shandong;Qingdao Special Food Research Institute,Qingdao 266109,Shandong)
出处
《中国食品学报》
北大核心
2025年第4期289-300,共12页
Journal of Chinese Institute Of Food Science and Technology
基金
“十四五”国家重点研发计划项目(2022YFD1600704)。
关键词
猕猴桃
脉冲超声
糖液
渗透脱水
电学特性
kiwifruit
pulsed ultrasound
sugar solution
osmotic dehydration
electrical characteristics
