Utilisation of preharvest dropped apple peels as a flour substitute for a lower glycaemic index and higher fibre cake

Fibre-enriched materials (FEMs) obtained from preharvest dropped apple peels were utilised as a source of dietary fibre in baked cakes and their effects on the textural/nutritional qualities and starch digestibility (glucose release behaviour, starch digestion fraction, predicted glycaemic index) of the cakes were evaluated. When FEMs were incorporated into the cake formulation (3?g and 6?g of dietary fibre per serving (100?g)), the volume of the cakes seemed to be reduced and their texture become harder. However, 3?g of FEMs did not degrade the cake qualities. The use of FEMs in cakes significantly reduced the levels of rapidly digestible starch and slowly digestible starch, while the levels of resistant starch increased. Additionally, the cake samples prepared with FEMs exhibited a lower predicted glycaemic index. This study may give rise to multi-functional bakery products with acceptable quality and low glycaemic index.