Look for these signs of high-quality potatoes:1. Firm and smooth,not soft or shriveled. 3. Shallow eyes. 4. No sprouts. Sprouting potatoes are high in sugar. 5. No green color. Green areas develop on potatoes stored in light. These areas contain a substance called solanine, which has a bitter taste and is poisonous in large quantities. All green parts should be cut off before cooking. 6. Absence of cracks, blemishes, and rotten spots. Was this article helpful?