采后果蔬损伤检测研究进展

简介了果蔬采后损伤检测的研究进展。其中视觉观察是最为简单而常用的手段,能直接了解果蔬表面损伤的情况,如挤伤、开裂等;但可靠性相对较低。由于仪器分析可减少人为误差;因而,在实验室和商业上使用常常优于感观评价,并且能为研究人员、产业部门和消费者所接收。虽然能量吸收和声音、超音振动技术可反映采后果蔬内部的损伤情况,但这两种技术仅用于对果蔬挤伤敏感性的分析。与荧光和延迟光发射的方法只适用于含叶绿素的果蔬材料相比,光谱分析可广泛用于所有的果蔬损伤的检测;但这些方法只能用于果蔬表面损伤的评价。对研究人员和产业部门来讲,最大希望能更好地了解果蔬采后处理和流通过程中内部损伤的情况。目前,X-射线分析、磁场共振图像和激光检查虽能检测果蔬内部不同的损伤程度,但由于成本高,使用范围十分有限,未能在商业上应用。同其它所有技术一样,上述技术的检测成本正迅速下降;同时检测能力迅速提高。另外,利用生理活性,如呼吸速率、乙烯释放率和渗透率检测果蔬内部损伤的技术正在研制过程中。随着仪器、设备灵敏度的提高,这些技术的应用将成为可能。由于果蔬内部损伤包括多个方面,而每一种检测方法又针对某一特定的特性进行;因此,需要采用数学分析,结合每一种测定方法,这样才能确切反映果蔬内部的损伤情况。在将来可望采用一组检测器元件,通过指纹图像了解采后果蔬内部损伤及严重情况

Advances in Evaluations of Damage of Postharvest Fruits and Vegetables

Progresses in evaluations of damage of postharvest fruits and vegetables are reviewed. Visual inspection is simple but useful method to assess physical damage, such as bruising and crack; however, it can relatively be less reliable. Generally, instrumental measurements are often preferred over sensory evaluations in laboratory and commercial situations because they reduce variations in judgment among individuals and provide a common language among researchers, industry and consumers. Energy absorption and sonic and ultrasonic vibration may reflect the status of internal damage, but both techniques are more suitable for assessing bruise susceptibility. Compared with application of fluorescence and delayed light emission to chlorophyll containing fruits and vegetables, optical absorbance to all fresh produce is widely tested to evaluate damage. However, these methods developed are essentially for detection of physical damage. For researchers and industry, an exciting prospect arises from a better understanding of internal damage of fruits and vegetables during postharvest handling and distribution. X ray analysis, magnetic resonance imaging, and laser inspection can now be used to detect the internal damage in some limited application; but not practical for routine damage testing because the equipment is expensive. Like all other technologies, costs and capabilities are rapidly improving. Other techniques related to physiological activities, such as respiration rate, ethylene evolution rate, and leakage rate, are also developed, and, furthermore, the increasing sensitivity of the equipment could make these techniques more available. Since internal damage comprises many properties or characteristics, and each method is based on the measurement of a given property, it is important to mathematically combine each measurement and then to exactly reflect the damage. It is expected that a battery of several detectors can produce a fingerprint that may indicate presence or degree of damage of postharvest fruits and vegetables.