Abstract

The evaluation of the maturity and ripening of fruits is important from both consumer and industry point of view in order to produce high quality horticultural products. This requires the need to explore the potential of reliable, cost effective and fast data acquiring techniques that have practical applicability for the nondestructive monitoring of fruits. Therefore, the present study explores the utility of confocal micro Raman spectroscopy for the nondestructive, extraction-free evaluation of biochemical changes associated with the ripening of jamun fruits. For this, the exocarp, mesocarp and seed of the jamun fruits have been examined at green, green-pink, reddish-pink, light-purple, dark-purple and blackish-blue stages of growth and ripening. The analysis of the acquired Raman spectrum of the exocarp and mesocarp of jamun shows the spectral features of starch, glucose, fructose, carotenoids, anthocyanins and flavonoids. In addition, seeds are rich in carotenoids and flavonoids. The decrease in the intensity of the starch band and simultaneous increase in the intensity of glucose and fructose bands at the onset of ripening indicate that ripening is associated with a decrease in non-reducing sugars with subsequent accumulation of reducing sugars. The appearance of the spectral features of anthocyanins and carotenoids in the ripe fruits indicates significant accumulation during ripening. The obtained spectral features may be used to monitor the maturity and ripening of the fruits in order to determine the appropriate harvest time to maximize fruit quality and minimize postharvest losses.

摘要

从消费者和行业的角度来看，水果成熟度和成熟度的评估对于生产高质量的园艺产品都很重要。这需要探索可靠、经济和快速的数据采集技术的潜力，这些技术对水果的无损监测具有实际适用性。因此，本研究探讨了共焦显微拉曼光谱在非破坏性、免提取评估与果酱成熟相关的生化变化方面的应用。为此，在绿色、绿色-粉红色、红-粉红色、浅紫色、深紫色和黑蓝色的生长和成熟阶段对 jamun 果实的外果皮、中果皮和种子进行了检查。获得的jamun外果皮和中果皮的拉曼光谱分析显示了淀粉、葡萄糖、果糖、类胡萝卜素、花青素和类黄酮的光谱特征。此外，种子富含类胡萝卜素和类黄酮。在成熟开始时淀粉带强度的降低以及葡萄糖和果糖带强度的同时增加表明成熟与非还原糖的减少以及随后的还原糖的积累有关。成熟果实中花青素和类胡萝卜素的光谱特征的出现表明在成熟过程中显着积累。获得的光谱特征可用于监测果实的成熟度和成熟度，以确定适当的收获时间，以最大限度地提高果实质量并最大限度地减少收获后的损失。