title: Vitamin C losses in some frozen vegetables due to various cooking methods.
abstract: Frozen spinach, peas, green beans and okra were commercially cooked in three different stewpans (double based stainless steel, teflon, pyrex) with and without thawing. The vitamin C levels were effected both by cooking methods and stewpans. Frozen peas were found to be the least (3.5% loss), and frozen green beans were found to be the most (19.6% loss) effected vegetables by thawing. In all of the stewpans, double based stainless steel pan retained more vitamin C than the others. While boiling spinach, peas, green beans, and okra without thawing resulted 46.5, 25.2, 18.2, and 21.6% vitamin C loss in double based stainless steel pan, boiling them in pyrex pan resulted 58.5, 36.0, 42.1, and 28.2% vitamin C loss, respectively. Besides, the losses in cooking processes were accelerated in thawed vegetables with the same tendency; that is more destruction occurred in samples boiled in pyrex pan (60.3% loss in spinach, 40.8% loss in peas, 48.4% loss in green beans, and 41.6% loss in okra). According to the results, it was found that thawing before cooking is useless and causes more vitamin C loss. Therefore, frozen vegetables must not be thawed before cooking. In order to prevent vitamin C from destruction, using double based stainless steel pan, minimum amount of water and cooking of frozen vegetables are recommended.
authors.affiliation: Hacettepe University, Department of Nutrition and Dietetics, TR-06100 Sihiye, Ankara, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Nursal
authors.forename: S
authors.initials: S
authors.lastname: Yücecan
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis*; D003296:Cooking; D005519:Food Preservation; D005615:Freezing; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D014675:Vegetables / Q000737:chemistry*
chemical_list: D001205:Ascorbic Acid