Effect of exposure to light on the solanine content of two varieties of potato (Solanum tuberosum) popular in Jordan

An analysis of random samples of potatoes (Solanum tuberosum) from local markets in Jordan showed that many whole tubers had solanine contents above the recommended level of 20 mg/100 g (fresh weight) of potato, while the maximum level in the skins was 128 mg/100 g. Exposure of two local varieties, Draga and Sponta, to direct or diffuse sunlight generated comparable levels over a 3-week period, but differences between the varieties were significant. It is suggested that growers in countries with Mediterranean climates should select varieties that generate low levels of solanine, remove the tubers from the field immediately after harvest and store the crop in the dark.