Optimization of African Breadfruit Based Complementary Food Using Mixture Response Surface Methodology

Aims: To model and optimize complementary foods based on their mixture ingredients viz. African breadfruit, soybean and maize, and their depending quality characteristics namely, energy, carbohydrate, fat, ash, protein, flavor, taste, general acceptability and paste viscosity, and determine the amino acid qualities of the optimized formula.

Study Design: Experimental research (controlled experiment).

Place and Duration of Study: The Department of Food Science and Technology, Michael Okpara University of Agriculture, Umudike between 2011 and 2015.

Methodology: The D-optimal three factor mixture design fitted into the second order canonical model was adopted, and the factor ranges were set at 64-80 % (African breadfruit), 19-35 % (soybean) and 1-9 % (maize) which yielded twenty blends (including replications) based on the mixture design combination. Each mixture component was expressed as a proportion of the mixture such that the sum was equal to 100 %.

Results: The results of the analyses were: 379.51-411 kcal/100 g (energy), 53.59-63.62 % (carbohydrate), 8-6 % (fat), 3.03-4.28 % (ash), 10.31-14.64 % (protein), 6-like slightly to 8-like very much (flavor, taste and general acceptability) and 5770-5800mPa.s (paste viscosity). Protein and energy were exceptionally high with all the values of protein exceeding the minimum standard recommended for complementary foods. The models for energy, fat, taste and paste viscosity were excellent for prediction due to the quality of their PRESS and predicted r-squared hence their selection for the numerical optimization which resulted in the prediction of 69:24:7 (African breadfruit: soybean: maize) as the optimized formula. Amino acid evaluation of this optimized formula showed that the values compared favourably with standards (WHO/FAO/UNU reference pattern and egg reference protein).

Conclusion: The selection of 69:24:7 as the optimized formula indicates that complementary food can be produced with the African breadfruit as a base at 69% inclusion, while its amino acid profile suggests that its protein could be nutritionally adequate.