Grapefruit is considered a fruit of good nutritional value provide us with many useful nutrients and has many benefits in the food processing. Also the grapefruit peels contain innumerable nutrients and used in the making of jam and desserts. The current study aimed to utilize the whole grapefruit peels flour in cake fortification. Study included determination of gross chemical composition, caloric value, physical, sensory properties of the studied cakes likewise; staling rate and loss of freshness of studied cakes were assessed. The data revealed that incorporation of both wheat flour and treated whole grapefruit peels flour (TGPF) increased moisture, ash and crude fiber to (25.51%- 28.45%); (3.95%-4.42%) and (0.81%-2.22%); respectively. The results showed that 5%, 10%, 15% and 20% TGPF had a different effect on all studied sensory and physical characteristics of all studied cakes. Moreover, cake with 5%, 10% TGPF was recorded the best scores of all studied sensory characteristics in fortified cakes. The staling rate mean values of the different cake samples were reduced gradually during storage for 2, 4, 6 and 8 days. The higher freshness (27.21%) was assessed in cakes fortified with 15% TGPF. The results showed that cake fortified with 20% TGPF had the highest staling value (362.20%) after 8 days of storage as compared to all other cakes samples. Consequently, it recommended utilizing the grapefruit peels to enhance the nutritional values of cake.

Key words: Grapefruit peels, Chemical composition, Cake Staling, Physical and Sensory Characteristics.