Comparative analysis of fruit-based functional snack bars

The aim was to develop snack bars with high dietary fibre (DF) and polyphenol contents. Snack bar base was formulated without (control bar) or with fibre (inulin or apple DF bar). Snack bar filling was formulated with or without apple polyphenol extract (APE). Nutritional assessment of snack bars was based on the total DF, phenolics, protein, fat, uronic acid (UA) and moisture contents, water activity, Hunter L∗a∗b∗ colour, hardness, and phenolic composition. Results showed that snack bars with added apple DFs gave the highest amount of total DF (∼5.3% w/w). Good quantities of phenolics were also retained in the snack bars with added apple DF and APE after baking. With APE in the bar filling, the snack bars enhanced with apple DF or inulin had higher levels of extracted phenolics (2.87 and 2.22 mg catechin equivalent (CtE)/g bar) than the control bars (1.45 mg CtE/g bar). The phenolic profiles of snack bars obtained by HPLC resembled that of the APE ingredient. The Hunter L∗a∗b∗ colour and water activity values suggested that the addition of APE did not cause extra browning and the resultant snack bars would possess a good shelf life. Therefore, snack bars enhanced with apple DF and APE may be a convenient functional food, offering a good source of DF and apple polyphenols.