Nutrient Conservation in Canned, Frozen and Fresh Foods
Canned food? Nutritious? You bet! In fact, canned fruits and vegetables are as equally nutritious as their fresh and frozen counterparts when prepared for the table.
According to a study conducted by the University of Illinois Department of Food Science and Human Nutrition, canned fruits and veggies provide as much dietary fiber as their fresh and frozen counterparts, and are a convenient weapon in helping to combat the risk of heart disease and some types of cancer.
Key findings from the nutrition study included:
- Many canned fruits and vegetables are high in vitamin A and related carotenes, antioxidants that provide essential protection for the body's cells. Canned products packed with carotenes include: green and yellow vegetables, sweet potatoes, carrots, peaches, pumpkin and apricots.
- Canned tomatoes, in particular, contain an important carotenoid called lycopene, which other studies have found that it appears to help prevent prostate cancer. In fact, some analyses show lycopene is more effective when eaten after heating or canning the tomatoes.
- Canned poultry and fish stack up well against fresh and frozen versions, with similar levels of protein and vitamins. Canned salmon is higher in calcium - a vital nutrient needed to maintain strong bones and teeth - than fresh or frozen salmon.
- Recipes with canned ingredients provide comparable nutritional value. For instance, a spaghetti sauce recipe made with canned tomatoes provides more fiber, potassium, vitamin A, vitamin C, calcium and iron than the same recipe using fresh tomatoes.
- Many canned fruits and vegetables, particularly varieties of beans, are a valuable source of soluble fiber, which other research has shown reduces blood cholesterol and gastrointestinal problems that increase the possibility of certain cancers. The researchers also stated the heating process during canning appears to make fiber more soluble, and therefore, more useful to the body.
- Most vitamin C is retained after canning and remains stable during the one- to two-year shelf life of the product. Significant sources of vitamin C include canned apricots, asparagus, oranges, grapefruit, pineapple, strawberries, spinach and tomatoes.
- Folate is an important nutrient that helps to regulate blood pressure and kidney functions. Recent studies indicate folic acid also plays a key role for women in prenatal care and during pregnancy. Look for significant levels of the Recommended Daily Intake (RDI) of folate in canned beans (20 to 40 percent) and asparagus (25 percent).
In conjunction with the Canned Food Alliance (CFA), researchers from the University of Illinois have established a Web site to provide a complete listing of the 1997 nutrition study components.