Quantifying risk factors associated with light-induced potato tuber greening in retail stores

Abstract

Light conditions in retail stores may contribute to potato greening. In this study, we aimed to develop a potato tuber greening risk rating model for retail stores based on light quality and intensity parameters. This was achieved by firstly exposing three potato varieties (Nicola, Maranca and Kennebec) to seven specific light wavelengths (370, 420, 450, 530, 630, 660 and 735 nm) to determine the tuber greening propensity. Detailed light quality and intensity measurements from 25 retail stores were then combined with the greening propensity data to develop a tuber greening risk rating model. Our study showed that maximum greening occurred under blue light (450 nm), while 53%, 65% and 75% less occurred under green (530 nm), red (660 nm) and orange (630 nm) light, respectively. Greening risk, which varied between stores, was found to be related to light intensity level, and partially explained potato stock loss in stores. Our results from this study suggested that other in-store management practices, including lighting duration, average potato turnover, and light protection during non-retail periods, likely influence tuber greening risk.

A Review on Greening and Glycoalkaloids in Potato Tubers: Potential Solutions

“…Several lighting conditions were studied by researchers trying for better potato display to reduce greening such as dull daylight conditions (140 μmol –1 m –2 ) for 7 days, cool white fluorescent light for ten days, and creating a grocery store environment using fluorescent white light (200 ft candles) at room temperature for 4 days . Recently, Tanios et al have reported an influence of light exposure at retail stores on the greening of potato varieties (Maranca, Nicola, and Kennebec). The blue light (450 nm) had maximum effect on greening, followed by green light (530 nm) with 53% less, red light (660 nm) with 65% less, and orange light (630 nm) with 75% less greening.…”

“…Greening of potatoes mostly occurs on the skin or toward the surface, as shown in Figure 4. The measurement of greening is mostly visual observation; 25 however, it can be scientifically measured by colorimeter, 26 fluorimeter, 25 or a visible/nearinfrared (VIS/NIR) DA-meter, which measures color in index of absorbance difference. 27 Total glycoalkaloids are mainly present in the skin and around the eyes 28 of the potato, which is generally called the growing point on potatoes and where sprouts start developing.…”

“…Greening of potatoes mostly occurs on the skin or toward the surface, as shown in Figure . The measurement of greening is mostly visual observation; however, it can be scientifically measured by colorimeter, fluorimeter, or a visible/near-infrared (VIS/NIR) DA-meter, which measures color in index of absorbance difference …”

“…The increase in the content of TGA is associated with the wavelength, duration of exposure, and the intensity of light. , The quality and quantity of light play essential roles in developing TGA in stored potatoes , and are greatly influenced by the spectral composition of the light source. Some studies showed that different light sources and wavelengths of light resulted in a reduced risk of TGA production. Mekapogu et al have studied the effect of light qualities (yellow, green, blue, red, purple, fluorescent, and UV lights) on Haryoung and Atlantic cultivars of potato.…”

Discolouration of Potato Tubers Under Retail Light: Cultivar Variations and Effect of Different Packaging Materials for Folva Potatoes Stored at 20 and 6 °C

“…Although no metabolic connection has been established between the two processes, contents of GA may be partly predicted from colour changes (Tilahun et al 2020). Green potatoes are generally considered unfit for human consumption and are identified as the primary reason for customers not purchasing potatoes (Tanios et al 2020). For the Norwegian retail chains, the total potato waste in 2020 due to green potatoes was estimated to be 200 tons at a value of 250,000 Euro (Pål Westby, Norgesgruppen).…”