EVALUATION OF PROXIMATE, MICROBIOLOGICAL AND PASTING PROFILES OF CUSTARD SUPPLEMENTED WITH LIMABEAN AND RIPE PLANTAIN FLOURS

Onwuama, N.N.¹, Okoye, J.I.² and Eze, S.I^3
1Department of Nutrition and Dietetics, University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu, Nigeria.
²Department of Food Science and Technology, Enugu State University of Science and Technology, Enugu, Nigeria
³Department of Home Economics, Federal College of Education, Eha Amufu, Enugu, Nigeria.
*Corresponding Email: okoyejoseph6@gmail.com

ABSTRACT

This study was designed to evaluate the proximate composition, microbiological and pasting properties of custard supplemented with lima bean and plantain flours. The lima bean and plantain flours were separately prepared from lima bean seeds and ripe plantain fruits and used at varying replacement levels (5-25% and 5-25%) for cornstarch in the production of custard formulations with the custard produced from 100% cornstarch used as control. The custard formulations produced were analysed for proximate, microbiological and pasting properties using standard methods. The moisture, crude protein, fat, ash and crude fibre contents of the samples increased significantly (p<0.05) with increase in substitution of lima bean and plantain flours from 9.19-9.91%, 9.18-19.42%, 2.10-3.23%, 3.38-3.67% and 3.38-4.90%, while the carbohydrate and energy contents decreased from 72.98-58.90% and 347.44-342.27KJ/100g, respectively. The control sample (Custard produced from 100% cornstarch) had the highest carbohydrate (72.98%) and energy (347.44KJ/100g) values, respectively. The microbial counts of the custard samples showed that the total viable count of the samples ranged from 0.32 x 104 -1.20 x104cfu/g, while the coliform and fungal counts were nil which is an indication that the products were safe and fit for human consumption. The pasting properties of the samples showed that the peak, breakdown, set back, final and trough viscosities as well as the pasting temperature and peak time of the custards increased significantly (p<0.05) with increase in the addition of lima bean and plantain flours from 27.16-62.84RVU, 68.15-110.70 RVU, 58.89-97.56 RVU, 36.78-77.29 RVU, 63.04-97.49RVU, 76.10-83.57oC and 5.40-7.03 min, respectively. The control sample (Custard made with 100% cornstarch) had the least values in all the pasting parameters evaluated compared to the substituted samples. The study, therefore, showed that the macronutrient contents and the pasting properties of custard samples could be improved by supplementing cornstarch with lima bean and plantain flours at different proportions, thereby extending the use of these locally available novel flours in the preparation of good quality and acceptable custard formulations.

Keywords: Custard, supplementation, proximate composition, microbial quality, pasting properties, lima bean flour, ripe plantain flour.