Effect of substituting chia (Salvia hispanica L.) seeds flour and gel for wheat flour and egg on the quality of cookies and cake

The present study aims to determine the nutrient content, functional properties and sensory characteristics of cookies and cakes made from flour substituted partially by chia seeds (Salvia hispanica L) flour and gel as follow: 1) partial replacement of wheat flour by 25% chia seed flour and 2) total replacement of eggs by chia gel, in comparing with traditional cookies and cake formulation as control samples. Results revealed that overall acceptability of control samples recorded the highest value followed by samples with chia gel then 25% whole chia flour blending. Significant increase (p<0.05) in weight, diameter and height were observed in cookies samples blended with 25% whole chia flour. Meanwhile, significant increase (p<0.05) in volume and specific volume were observed by the whole replacement of egg with chia gel in cookies samples in comparing with the control ones. Significant differences (p<0.5) were observed amongst cake samples in weight, volume and specific volume. Cake samples with completely egg substitution with chia gel recorded the highest weight and volume. The partial substitution of wheat flour by 25% chia seed flour caused significant increasing (p<0.05) in protein, ash, fat  and total energy and significant decreasing (p<0.05) in moisture and carbohydrate in both cookies and cake samples in comparing with control ones. On the other hand total replacement of eggs by chia gel in cookies caused a significant increasing (p<0.05) in all chemical composition parameters except carbohydrate which decreased by adding chia flour comparing with the control samples. Protein, carbohydrate and total energy values were decreased by substitution egg in cakes with chia gel. Also, cookies and cake samples substituted with chia flour or gel recorded higher values in protein, amino acid content, amino acid scores (AAS), essential amino acid index (EAAI), biological value (BV) and protein efficiency ratio (PER) than the control samples.  In conclusion, the substitution of cookies and cake  flour and eggs with chia seeds flour and gel were affected on their nutritive value, functional properties and sensory characteristics. Thus, we recommended to use chia seeds flour and gel in our daily meals and dishes in general and in particular for the people who suffering from healthy problems as the result of consumption food products containing egg.