For most fruits and vegetables, there is a difference in taste and texture between fresh and canned or frozen versions. However, nutritional analysis verifies that fresh, canned and frozen fruits and vegetables are practically identical in vitamin content. Many consumers have the notion that frozen and canned varieties 'don't count' when in fact they are sometimes more nutritious than those found in the produce aisle because they are harvested and preserved at the peak of freshness. Fresh produce often loses some of its nutrients during shipping, while at the store, and in consumers' refrigerators. The lycopene in tomatoes, for example, is in fresh tomatoes, canned tomatoes and spaghetti and pizza sauce.
Evidence shows that processing actually improves the bioavailability of lycopene.
Processing can also add a safety advantage to some products. Traditional pasteurization, or heating to destroy harmful bacteria, has been recognized as a food safety advantage for decades, and is considered one of the major advanced in public health. When milk pasteurization was discussed in the early 1900's, the concern was tuberculosis as well as other illnesses then could be transferred by raw milk. More recently, pasteurization is being applied to apple cider. On the other hand, heat treatment of cider is critical because the benefits of additional protection from E. coli can be life saving.