Most red flags for tomatoes are in opposition to the green flags. Avoid tomatoes with blemishes, wrinkles, mold, a squishy texture, or an unpleasant smell.
Green flags to look for in bananas are a bright yellow color with a firm texture. Avoid bananas with loose or missing stems, a lack of black tips, or an overly sweet smell.
Major green flags are shiny, unblemished skin, regardless of the color of pepper you're purchasing. They should feel heavy, and the texture should be firm.
Avoid buying bell peppers with wrinkly skin, soft spots, black or brown discoloration, sliminess that doesn't rinse away with water, mold spores, or an acrid smell.