Spoiled ground beef often shows clear signs of decay. A sour smell, sticky texture, or grayish color usually signals it is no longer safe to use. Even if the expiration date has not passed, storage conditions can affect its quality. When in doubt, it is always safer to discard questionable meat. https://www.dskkblade.com/blogs/food-news/how-long-is-ground-beef-good-in-the-fridge