title: Effect of different cooking methods on color, phytochemical concentration, and antioxidant capacity of raw and frozen brassica vegetables.
abstract: This study evaluated the effect of common cooking practices (i.e., boiling, microwaving, and basket and oven steaming) on the phytochemical content (carotenoids, chlorophylls, glucosinolates, polyphenols, and ascorbic acid), total antioxidant capacity (TAC), and color changes of three generally consumed Brassica vegetables analyzed fresh and frozen. Among cooking procedures, boiling determined an increase of fresh broccoli carotenoids and fresh Brussels sprout polyphenols, whereas a decrease of almost all other phytochemicals in fresh and frozen samples was observed. Steaming procedures determined a release of polyphenols in both fresh and frozen samples. Microwaving was the best cooking method for maintaining the color of both fresh and frozen vegetables and obtaining a good retention of glucosinolates. During all cooking procedures, ascorbic acid was lost in great amount from all vegetables. Chlorophylls were more stable in frozen samples than in fresh ones, even though steaming methods were able to better preserve these compounds in fresh samples than others cooking methods applied. The overall results of this study demonstrate that fresh Brassica vegetables retain phytochemicals and TAC better than frozen samples.
authors.affiliation: Department of Public Health, University of Parma, Parma, Italy. nicoletta.pellegrini@unipr.it
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Pellegrini
authors.forename: Emma
authors.initials: E
authors.lastname: Chiavaro
authors.forename: Claudio
authors.initials: C
authors.lastname: Gardana
authors.forename: Teresa
authors.initials: T
authors.lastname: Mazzeo
authors.forename: Daniele
authors.initials: D
authors.lastname: Contino
authors.forename: Monica
authors.initials: M
authors.lastname: Gallo
authors.forename: Patrizia
authors.initials: P
authors.lastname: Riso
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Fogliano
authors.forename: Marisa
authors.initials: M
authors.lastname: Porrini
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001937:Brassica / Q000737:chemistry*; D002338:Carotenoids / Q000032:analysis; D005511:Food Handling / Q000379:methods*; D010858:Pigmentation; D014675:Vegetables / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D002338:Carotenoids