The factors affecting greening of potatoes include more than light exposure. Greening is affected by variety, maturity and age, temperature, intensity and quality of light, and duration of light. White skinned varieties often green more readily than the red or russet varieties. The latter can green also but it may be masked and not as easily detected. Immature potatoes and those recently harvested green more readily due to lack of a thick outer skin.
Retail packaging can also contribute to increased greening.
Consumers want to be able to view produce prior to purchase. Packaging materials have changed over time from burlap and other opaque materials to transparent bags which allow exposure to light during retail storage and display. Consumers should be aware that some greening of potatoes is not unusual and may be more prevalent in some varieties than others. Excessive greening should be used as a symptom that solanine may also be present. A bitter taste will verify its presence.