Effect of Light-Emitting Diodes (LEDs) on the Quality of Fruits and Vegetables During Postharvest Period: a Review

Abstract

Major losses of fresh horticultural produce transpire during postharvest storage due to prompt senescence and diseases. The traditional postharvest preservation techniques used after harvest are based on cooling and the application of chemical preservation techniques. As a residue-free physical sterilization and preservation method, light-emitting diode (LED) treatment, has recently been applied for postharvest storage of fruits and vegetables by numerous researchers. This paper reviews the recent applications of LEDs in postharvest storage of fresh produce, including its effect on physiological characteristics, secondary metabolism, nutritional attributes, ripening process, senescence, shelf-life improvement, and pathogenic microbial spoilage of fruits and vegetables. LED treatment has promoted the accumulation of different phytochemicals, such as phenolic compounds, vitamins, glucosinolates, chlorophyll, total soluble solids, and carotenoids. Changes in the nutritional content, anthocyanin content, antioxidant capacity, and ripening were also observed after the treatment. Reduction in microbial spoilage and delay senescence were evident after the LED exposure. The influence of LED light depended on the fruit and vegetable variety. Therefore, LED treatment is an efficient and promising strategy for extending the storage life of fruits and vegetables with enhanced nutritional values.

Challenges and Opportunities of Light-Emitting Diode (LED) as Key to Modulate Antioxidant Compounds in Plants. A Review

“…Unlike HID and HPS, LEDs show reduced heat emission leading to prevent thermal degradation and optimizing space in indoor farming and storage management applications. Moreover, LED technology, compared to conventional lamps, enables a wide variety of spectral outputs and allows for controlling the directionality of light and regulating light intensity, all of which make it more suitable for the growth, preservation, and storage of fresh horticultural products [ 180 , 181 , 182 ].…”

“…Although several studies have addressed the benefits of LEDs for the growth of horticultural crops and the enhancement of their nutritional value, the findings about their effect on the quantity and quality of the plant crops in the postharvest stage are relatively recent and focused on few fruits and vegetables species [ 182 , 184 ]. There is evidence that LED lighting can influence the shelf life and quality of fresh produce, inhibiting weight loss, senescence, and over-ripening, and enhancing the production of antioxidant compounds [ 55 , 56 , 73 , 98 , 108 , 135 ].…”

“…LED technology provides unique advantages over the conventional lighting systems and proves to be extremely versatile. LEDs have the potential to regulate several aspects of plant growth, development, the accumulation of different secondary metabolites ( Figure 6 ) [ 182 ], and the overall plant metabolome [ 226 ].…”

“…Senescence is an unwanted phenomenon which leads to the loss of the nutritional and commercial value of the product. Generally, weight loss, oxidation, loss of pigments, yellowing in green vegetables due to chl degradation, and alteration of transpiration and respiration processes characterize senescence [ 182 ]. BL, RL, and GL can directly affect pigment accumulation, the antioxidant status, and photosynthesis, thus slowing senescence and extending the shelf life of fruits and vegetables.…”

Chlorophyll fluorescence imaging for process optimisation in horticulture and fresh food production

“…During storage, but most of all in the display cabinets in shops, quality of fruit and vegetables is further interactively affected by temperature and by the illumination system used (Prange and Lidster 1991, Herppich 2003, Kong et al 2021. The positive effects of low-light treatment have become increasingly obvious since LED facilitated the controlled postharvest application of low photosynthetic photon fluxes during recent years (Nassarawa et al 2021). CFI analyses easily and noninvasively verified that optimised low illumination indeed improved quality maintenance of packed photosynthetic active corn salad, arugula, and spinach leaves (Herppich 2003, Gergoff Grozeff et al 2013) by reducing microbial decay and leaf senescence during 10 d-storage at 18°C.…”