基于NMR和(1)^H-MRI技术的不同糖度锦绣黄桃耐贮性评价

Storage endurance evaluation of’jinxiu’yellow peach with different sugar content based on NMR and(1)^H-MRI techniques

目的:评价不同含糖量黄桃果实的耐贮性。方法:将不同含糖量的锦绣黄桃贮藏于(2±0.5)℃的冷库中,测定贮藏0,14,21,28,35,(35+3)d的果实呼吸强度、乙烯释放速率、可溶性固形物含量、质构,并利用核磁共振技术(NMR)和质子核磁共振成像((1)^H-MRI)技术测定果实自由水含量和弛豫时间以观察贮藏期间果实变化规律。结果:贮藏期间,低糖组果实果肉组织硬度、果肉紧实度及果实咀嚼性特性下降速率较快,尤其是贮藏后期(14~35 d)水分丧失量较大,耐贮性较差;高、中糖组果实质构品质保持较好,耐贮性好,贮藏前期(0~21 d)水分含量较高且无明显变化,贮藏后期水含量略下降但仍高于低糖组。结论:含糖量高的锦绣黄桃货架期可达3 d,在贮藏期间可保持较高的自由水含量和品质,耐贮性较好,0~14 d为冷藏下的优质保鲜期,21 d为安全保鲜期,28~35 d为品质劣变期。

Objective:To evaluate the storability of yellow peach with different sugar content.Methods:The respiration intensity,ethylene release rate,soluble solid content and texture of the fruit stored at 0,14,21,28,35,(35+3)d were measured.Nuclear Magnetic Resonance(NMR)technique and proton magnetic resonance imaging((1)^H-MRI)were used to determine the content of free water(A)and relaxation time(T)to observe the changes of fruit stored at(2±0.5)℃.Results:During storage and shelf,the decrease rate of firmness of pulp,flesh compactedness and chewiness was faster in low-sugar group,especially at the later stage of storage(14~35 d)and shelf-life,the water loss was larger,and the storage tolerance was poor;Fruit texture and storability of high and medium sugar groups were maintained well,and the water content of high and medium sugar groups was higher than that of low sugar group at the early stage of storage(0~21 d),but decreased slightly at the late stage of storage.Conclusion:’Jinxiu’yellow peach with high sugar content can keep high free water content and quality during storage,and has good storability.0~14 days is the high quality fresh preservation period,21 days is safety preservation period,28~35 days is the quality deterioration period,and the shelf life can reach 3 days.