Document Type: Original Article

Authors

1 Department of Food Science and Technology, School of Food Technology, Nutrition and Bio-engineering, Makerere University, Kampala, Uganda

2 Department of Food Technology and Nutrition, School of Food Technology, Nutrition and Bio-engineering, Makerere University, Kampala, Uganda

10.22077/jhpr.2020.2998.1113

Abstract

Purpose: Transformation of pumpkin flesh and seeds into dry flours increases their shelf stability and versatility. This study sought to optimise drying conditions for production of flour with high nutritional and nutraceutical value from flesh and seeds of C. pepo L var. fastigata using Response Surface Methodology, I optimal design. Research Method: Pumpkin flesh and seeds were dried following temperature time combinations got using I optimal design. All dry samples were tested for ascorbic acid, total carotenoids, total antioxidant capacity and starch digestibility. Seeds were also tested for in vitro protein digestibility, trypsin inhibitor activity, alpha tocopherol, beta tocopherol, and alpha tocotrienol. Findings: The predicted optimum drying conditions for production of C. pepo L var. fastigata flour with maximum nutritional quality and bioactivity were 57°C; 6.9 hours for flesh and 60°C; 3.15 hours for seeds. The most influential model terms were temperature for resistant starch, in vitro protein digestibility, trypsin inhibitor activity, total carotenoids, alpha tocopherol, beta tocopherol and alpha tocotrienol; quadratic term of temperature and time for ascorbic acid; and drying time for total antioxidant activity of the flesh and temperature for antioxidant activity for seeds. Research limitations: Dryer air flow rate was not included as a variable. Originality/Value: Results give, for the first time, an objective basis for choice of the drying conditions C. pepo L var. fastigata flesh and seeds for maximum nutritional and health benefits.

Keywords

Main Subjects

AOAC. (1995). Official methods of analysis (16th Edn). Washington (DC): Association of Official Analytical Chemists. Washington, D.C., USA.

Bradley, R. L. Jr. (2003). Moisture and total solids analysis. In: Food Analysis (3rd Edn). S. S. Nielsen (Ed). Springer Science+Business Media, LLC: New York, USA, 81-98.

Ceclu, L. S., Botez, E., Nistor, O. V., Andronoiu, D. G., & Mocanu, G. D. (2016). Effect of different drying methods on moisture ratio and rehydration of pumpkin slices. Food Chemistry, 195, 104-109. https://doi.org/ 10.1016/j.foodchem.2015.03.125

Damodaran, S. (1996). Amino acids, peptides, and proteins. In: Food Chemistry (3rd Edn). FennemaO. R (ed). Marcel Dekker, New York, 321-431.

Donlao, N., & Ogawa, Y. (2017). Impact of postharvest drying conditions on in vitro starch digestibility and estimated glycemic index of cooked non-waxy long-grain rice (Oryza sativa L.). Journal of the Science of Food and Agriculture, 97, 896-901. https://doi.org/10.1002/jsfa.7812 

Ekorong, F. J. A. A., Zomegni, G., Desobgo S. C. Z. & Ndjouenkeu, R. (2015). Optimization of drying parameters for mango seed kernels using central composite design. Bioresources and Bioprocessing, 2, 1-9. https://doi.org/10.1186/s40643-015-0036-x

Fagbemi, T. N. F., Eleyinmi, A. F., Atum, H. N., & Akpambang, O. (2005, July). Nutritional composition of fermented fluted pumpkin (Telfairia occidentalis) seeds for production of ogiri ugu. In Proceedings of the IFT Annual Meeting, Fermented Foods and Beverages: General, July 15-20, New Orleans, Louisiana.

Frick, L., & Doyle, R. (2015). LC/MS/MS quantitative analysis of fat soluble vitamins in serum. Agilent Technologies Inc: Lexington (MA).

Gregory, J. F III. (1996). Vitamins in food chemistry. In: Food Chemistry (3rd Edn). FennemaO.R (ed). Marcel Dekker, New York, 532-590.

Hsu, H. W., Vavak, D. L., Satterlee I. D., & Miller, G. A. (1977). A multi enzyme technique for estimating protein digestibility. Journal of Food Science, 42, 1269-1273.  https://doi.org/10.1111/j.1365-2621.1977.tb14476.x

Kim, M. Y., Kim, E. J., Kim, Y. N., Choi C., & Lee, B. H. (2012). Comparison of the chemical compositions and nutritive values of various pumpkin (Cucurbitaceae) species and parts. Nutrition Research and Practice, 6, 1-21. https://doi.org/10.4162/nrp.2012.6.1.21 

Marwah, R. G., Fatope, M. O., Mahrooqi, R. A., Varma, G. B., Abadi, H. A., & Al-Burtamani, S. K. S. (2007). Antioxidant capacity of some edible and wound healing plants in Oman. Food Chemistry, 101, 465–470.  https://doi.org/ 10.1016/j.foodchem.2006.02.001

Megazyme International. (2017). Resistant starch assay procedure. Megazyme International: Ireland, 1-15.

Mirhosseini, H., Rashid, N. F. A., Amid, B. T., Cheong, K. W., Kazemi, M., & Zulkurnain, M. (2015). Effect of partial replacement of corn flour with durian seed flour and pumpkin flour on cooking yield, texture properties, and sensory attributes of gluten free pasta. LWT-Food science and Technology, 63, 184-190. https://doi.org/10.1016/j.lwt.2015.03.078

Monteiro, R. L., Link, J. V., Tribuzi, G., Carciofi, B. A. M., & Laurindo, J. B. (2018). Microwave vacuum drying and multi-flash drying of pumpkin slices. Journal of Food Engineering,  232, 1-10.  https://doi.org/10.1016/j.jfoodeng.2018.03.015

Muanda, F., Koné, D., Dicko, A., Soulimani R., & Younos, C. (2009). Phytochemical Composition and Antioxidant Capacity of Three Malian Medicinal Plant Parts. Evidence-Based Complementary and Alternative Medicine, 2011, 1-8. https://doi.org/10.1093/ecam/nep109

Oh, I. K., Bae, I. Y., & Lee, H. G. (2018). Effect of dry heat treatment on physical property and in vitro starch digestibility of high amylose rice starch. International Journal of Biological Macromolecules, 108, 568-575. https://doi.org/10.1016/j.ijbiomac.2017.11.180

Park, S. J., Kim, T. W., & Baik, B. K. (2010). Relationship between proportion and composition of albumins, and in vitro protein digestibility of raw and cooked pea seeds (Pisum sativum L.) Journal of the Science of Food and Agriculture, 90, 1719-1725.  https://doi.org/10.1002/jsfa.4007

Pellegrini, N., Serafini, M., Colombi, B., Del Rio, D., Bianchi, S. S. M., & Brighenti, F. (2003). Total antioxidant capacity of plant foods, beverages and oils consumed in Italy assessed by three different in vitro assays.  The Journal of Nutrition, 133, 2812–2819  https://doi.org/10.1093/jn/133.9.2812

Potosí-Calvache, D. C., Vanegas-Mahecha, P., & Martínez-Correa, H. A. (2017). Convective drying of squash (Cucurbita moschata): Influence of temperature and air velocity on effective moisture diffusivity, carotenoid content and total phenols. Revista DYNA, 84, 112-119. https://doi.org/10.15446/dyna.v84n202.63904

Que, F., Mao, L., Fang, X., & Wu, T. (2008). Comparison of hot air-drying and freeze-drying on the physicochemical properties and antioxidant activities of pumpkin (Cucurbita moschata Duch.) flours. International Journal of Food Science and Technology, 43, 1195-1201. https://doi.org/10.1111/j.1365-2621.2007.01590.x

Rodriguez-Amaya, D. B., & Kimura, M. (2004). Harvestplus handbook for carotenoid analysis. HarvestPlus technical monograph 2. International Food Policy Research Institute [IFPRI] and International Center for Tropical Agriculture [CIAT]: Washington (DC).

Roongruangsri, W., & Bronlund, J. E. (2016). Effect of air-drying temperature on physico-chemical, powder properties and sorption characteristics of pumpkin powders. International Food Research Journal, 23, 962-972.

Roychaudhuri, R., Sarath, G., Zeece, M., & Markwell, J. (2003). Reversible denaturation of the soybean Kunitz trypsin inhibitor. Archives of Biochemistry and Biophysics, 412, 20-26. https://doi.org/10.1016/s0003-9861(03)00011-0

Stratil, P., Klejdus, B., & Kubán, V. (2006). Determination of total content of phenolic compounds and their antioxidant activity in vegetables--evaluation of spectrophotometric methods. Journal of Agricultural and Food Chemistry, 54(3), 607-616. https://doi.org/10.1021/jf052334j

Szmigielski, M., Wesolowska-Janczarek, M., & Szczepanik, M. (2010). Determination of trypsin inhibitor activity of microwave-heated bean seeds using Bromocresole purple index (BCPI). Polish Journal of Food and Nutrition Sciences, 60, 329-333.

Vamadevan, V., & Bertoft, E. (2015). Structure-function relationships of starch components-Review. Starch/Stärke, 67, 55-68. https://doi.org/10.1002/star.201400188