Alteration in phytochemicals from sweet maize in response to domestic cooking and frozen storage

Abstract

Sweet maize has worldwide importance due to its high nutritional value and health benefits. In order to provide valuable health-related information to consumers, the phytochemicals profile of raw sweet maize kernels and those exposed to different treatments (cooking, frozen storage before cooking, sucrose addition during cooking, and blanching) was examined herein. Thus, carotenoids, tocopherols and free phenolic acids content was determined by liquid chromatography, while the content of water soluble sugars was analyzed by anion exchange chromatography. In response to immediate cooking, as well as, to blanching prior to shorter frozen storage and cooking afterwards, all hybrids exhibited a significant decrease in carotenoids, and a significant increase in concentration of tocopherols, fructose, glucose, protocatechuic, ferulic and p-coumaric acids, in comparison to the fresh samples. However, treatments with blanching prior to longer frozen storage and cooking afterwards, contributed only to increased tocopherols content. Distinct grouping of processed samples in comparison to their corresponding control samples, revealed the existence of unique linkage between changes in phytochemicals content upon treatment in a hybrid-dependent manner. Combined blanching prior to shorter frozen storage with sucrose addition during cooking is highly recommended as a potent tool for phytochemicals enhancement.