Effect of steamable bag microwaving versus traditional cooking methods on nutritional preservation and physical properties of frozen vegetables: A case study on broccoli (Brassica oleracea)

• First study of steamable bag microwaving effect on frozen vegetable nutrition value
• First study of steamable bag microwaving effect on frozen vegetable physical property
• First comparison of this method and traditional cooking methods on studied properties
• Steamable bag microwaving improves broccoli antioxidant activity over thawed broccoli

The effect of steamable bag microwaving on the nutritional value and physical properties of frozen vegetables was studied and compared to that of traditional cooking methods (i.e., steamer steaming and traditional microwaving) for the first time. Broccoli was chosen for this study since it is one of the most consumed frozen vegetables. Titration, oxygen radical absorbance capacity assay, colorimetry (L*, a*, b*, hue angle, and total color difference) and texturometry were used for evaluation. The results show that steamable bag microwaving performs better than traditional microwaving and is equal to steamer steaming in retaining ascorbic acid content and increasing antioxidant activity compared to thawed frozen broccoli. Steamable bag microwaving tenderizes frozen broccoli faster, and better maintains the broccoli lightness and yellowness than steamer steaming and traditional microwaving. These findings show that steamable bag microwaving is a more appropriate cooking method for frozen broccoli than traditional cooking methods.Industrial relevanceSteamable bag microwaving is an emerging cooking technology for frozen vegetables. While steamable bag microwaving provides consumers with convenience and safety compared to other cooking technologies (i.e., traditional microwaving, steaming, and boiling), there is no information on the effect of steamable bag microwaving on nutritional and physical changes of frozen vegetables. Our findings show that steamable bag microwaving is more appropriate than traditional cooking methods and satisfies current consumers' needs better (i.e., high nutritional content, fresh-like produce, and time savings).