Old carrots should be peeled because their outer layer becomes thicker, bitter, and less palatable as they age, while fresh carrots have a thin, sweet skin that is perfectly edible and nutritious.
Freshly harvested carrots have a thin, delicate skin that is packed with nutrients and contributes to their overall sweetness. This outer layer is perfectly safe and enjoyable to eat. In fact, many people prefer to simply scrub fresh carrots clean rather than peeling them, preserving both the nutrients and the flavor.
However, as carrots age, their outer layer undergoes changes. It becomes thicker, tougher, and can develop a bitter taste. This is due to the carrot's natural defense mechanisms and the loss of moisture over time. Peeling older carrots removes this undesirable outer layer, revealing the sweeter, more tender flesh underneath. Peeling also helps to improve the carrot's texture and appearance, making it more appealing to eat.
Essentially, peeling old carrots is about improving their taste and texture by removing the less desirable outer layer that has developed over time. With fresh carrots, this layer is still thin, sweet, and nutritious, so peeling is unnecessary.
If you're unsure about the age of your carrots, give them a taste test. If the outer layer tastes bitter or tough, peeling is recommended. You can also try gently scraping the carrot with a knife; if the skin comes off easily and looks thin, it's likely a fresh carrot that doesn't need peeling.