Is Canned Food Fresher Than Frozen?

Canned and frozen foods are lifesavers, especially when their fresh counterparts aren't accessible. Since both canned and frozen foods are preserved rather than fresh, is one fresher than the other? The answer is yes — frozen foods are resoundingly fresher than canned. In fact, frozen foods can sometimes be even fresher than "fresh" foods. This applies to produce, meats, and seafood. 

Once produce reaches its peak freshness, it's picked from the ground or tree it grew on, and consequently, indicators of freshness like flavor, color, texture, and nutritional value will begin to degrade. However, freshness can be preserved if foods are frozen immediately after harvesting. Similarly, freezing meat right after its cut from the animal is the superior way to preserve freshness.

Unfortunately, the same is not always true for canning. Canning food necessitates intense heat or complete cooking, which destroys most of the vitamins present and also requires the addition of salt or sugar to preserve the flavor and integrity of the food during its extended storage. Frozen produce is also sometimes exposed to heat prior to freezing if it's blanched, a process where produce is boiled in water for a few minutes. Blanching eliminates only a small percentage of vitamins while also preserving flavor, color, and nutrients. This is why frozen peas can be so much better than fresh. As for meat and seafood, when frozen isn't an option, you can resort to canned versions which still have a favorable level of freshness. Plus, there's ways to make canned seafood taste like a million bucks.

Produce that's flavorful is often an indication of freshness, which means a higher nutritional content. Research reveals that fresh produce rich in vitamin C, such as spinach, can lose up to 100% of its vitamin C content within a week at room temperature and 75% when refrigerated for the same duration. (Vitamin C is highly sensitive to heat, light, and oxygen at specific temperatures and durations.)

However, blanching before freezing only removes a small percentage of vitamin C, allowing it to be retained while frozen, unlike fresh produce. The best way to preserve the vitamin content and freshness of raw meat is also by freezing. On the other hand, canned meats have already been cooked; resulting in a loss of water-soluble vitamins, similar to produce. That being said, some canned meats are better than others. The addition of salt may also pose a concern for some individuals. 

Vitamin content plays a significant role in determining the freshness of frozen or canned foods. Even still, regardless of the level of heat exposure, both frozen and canned foods retain their naturally occurring minerals (like potassium, iron, and calcium) as well as their macronutrients (including carbohydrates, protein, fats, and fiber). By striking a balance with both preservation methods, it's possible to create fresh tasting meals that are filled with flavor and are nutrient-rich.