模拟运输振动对不同堆高哈密瓜果实质地品质的影响

摘要

[目的]分析运输过程中不同堆高哈密瓜果实质地品质的连续变化,确定振动对不同堆高哈密瓜果实质地品质产生的影响,为哈密瓜冷藏运输调控品质提供依据.[方法]模拟运输振动试验,试验设置3个堆高处理,分别是顶层(9箱高)、中层(5箱高)、底层(1箱高),以静置哈密瓜作为对照(CK).试验温度在4～6℃,振动频率7 Hz的条件下连续开展14 d,每隔2 d取样,测取质地品质指标包括硬度、粘附性、内聚性、弹性、胶黏性、咀嚼性以及弹性模量,分析振动对不同堆高哈密瓜果实质地品质产生的影响.[结果]振动对果肉硬度影响较大,连续振动4 d,果肉硬度出现大幅下降,其中顶层果肉硬度降至初始值的38.3％,按影响大小排序:顶层>中层>底层;振动对果肉粘附性影响较明显,对不同堆高果肉粘附性影响大小排序:顶层>底层>中层;振动对果肉内聚性影响表现在前4 d延缓果肉内聚性降低,从第6 d开始加速果肉内聚性减小;振动对果肉弹性影响较明显,按影响大小排序:顶层>中层>底层;振动对果肉胶黏性影响较明显,连续振动4 d,各处理胶黏性均明显下降,底层果肉下降幅度最大,降至初始值的20.6％;振动对果肉咀嚼性和弹性模量影响较小.各项质地参数相关性分析结果表明:经过模拟运输振动,果肉硬度与咀嚼性和弹性模量呈极显著正相关(P中层>底层.[结论]低频振动会加速哈密瓜果肉软化,这种影响在连续振动4 d后尤为明显.振动对不同堆高哈密瓜果实质地软化程度影响大小排序:顶层>中层>底层.%[Objective] This study is designed to ascertain the effect on texture quality of Hami melon at different stacking heights by simulation of transport vibration in order to provide theoretical basis for refrigerated transport.[Method]Setting three treatment groups: top(9 boxes high),middle(5 boxes high)and bottom(1 box high).The immobile boxes were taken as the CK.The experiment lasted 14 d under 4-6℃ and the vibrational frequency was 7 Hz.Samples were checked every two days and the food texture was analyzed to measure the melon′s physical index,including hardness,adhesiveness,cohesiveness,elasticity,chewiness and elasticity modulus.Compared with CK,the vibration influence on the texture at different stacking heights of Hami melon was analyzed.[Result]The vibration had great influence on the pulp hardness,after continuous vibration 4 d,pulp hardness began to decrease sharply,the top′s dropped to 38.3％of the starting value.According to the degree,the order was: top>middle>bottom;The vibration had obvious influence on the adhesiveness,according to degree,the order was: top>bottom>middle;In the beginning of 4 d,the vibration postponed the decrease of melon′s cohesiveness,after 6 d,the vibration accelerated the decrease of melon′s cohesiveness;The pulp hardness dropped to the initial value of 38.3％.Vibration did not obviously influence the melon′s elasticity.According to the degree,the order was: top>middle>bottom;The vibration had obvious influence on the melon′s tackiness,after vibration for 4 d,each treatment group′s tackiness declined obviously,the bottom had the greatest decline,falling to 20.6％of the initial value;The vibration didn′t influence the melon′s chewiness and elasticity modulus obviously.Analyzing the texture parameters results showed that pulp hardness was positively correlated with chewiness and elasticity modulus(Pmiddle> bottom.[Conclusion]Low frequency vibration could accelerate the softening of melon pulp,and this influence appears obvious 4 days later.The vibration has influence on melon′s texture at different stacking heights: top>middle> bottom.