Ascorbic acid in processed plant-based foods

Abstract

Vitamin C (ascorbic acid or l-ascorbic acid) is an essential vitamin for humans and is vital for maintaining good health. As humans are unable to synthesise ascorbic acid, they are dependent upon its presence in their diet to meet their daily ascorbic acid needs. Plants are a good source of ascorbic acid and so it is not difficult for humans to obtain an adequate daily supply of ascorbic acid from a wide range of plant-based foods. However, the ascorbic acid content in plant tissues is variable and levels in fresh product can be affected from the time of harvest until ingestion. In addition, the increasing consumption of processed plant-based foods, rather than fresh product, has led to a considerable amount of research into the most appropriate processing methods to convert raw plant materials into plant-based foods while retaining high levels of ascorbic acid in the final food product. In this chapter, we discuss the impacts of conventional food processing techniques, such as blanching, frying, and freezing on ascorbic acid levels and how novel processing techniques, such as pulsed electric field and high hydrostatic pressure, could be used to improve the retention of ascorbic acid in plant-based foods. The importance of selecting appropriate food processing techniques to maintain both the levels and bioactivity of vitamin C in a range of different plant-based foods is critically evaluated.