EFFECT OF THE DRYING METHOD ON THE QUALITY AND DRYING CHARACTERISTIC OF MINT LEAVES (Mentha spicata L.)
Mint leaves are vegetables used for tea especially in the northern part of Nigerian because of their nutritional and medicinal values. Fresh mint leaves are perishable and to extend their shelf-life drying the leaves is a common practice among the people. The application of a proper drying method is essential to preserve its nutritional and medicinal values. Lack of information on the drying characteristic that could be used for the design of its dryers is a major bottleneck in its processing. This accounts for the poor colour, taste, flavour of dried mint leaves found in the market.In this study, three methods were used to dry mint leaves, sun, oven and shade drying methods. Proximate analyses were carried out on the samples dried with the three methods. Samples drying characteristics were investigated using an oven at 40, 50, 60 and 70 °C. The results show that the drying method significantly affected all the proximate compositions at 5% level. Shade drying has the highest crude protein and ash contents of 7.74% and 8.48% respectively. Carbohydrates were more (30.13%) when open sun drying was employed. Oven drying favoured lowest moisture content of 7.20%, highest crude fiber of 49.34% and highest crude fat contents of 9.22%. To dry mint leaves to equilibrium moisture content, it took 140 min for samples at a drying temperature of 40 °C, 120 min at 50 °C, 90 min at 60 °C and 70 min for 70 °C. Drying of the leaves occurred in a falling rate period.
AOAC, Official Methods of Analysis, (1984). 14th Edition, Association of Official Analytical Chemists. Washington DC.
AOAC, Official Methods of Analysis, (1990). 15th Edition, Association of Official Analytical Chemists. Washington DC.
Aniebo A. O. and Owen O. J. (2010). “Effect of Age and Method of Drying on the Proximate Composition of Housefly Larvae Meal (HFLM)”. Pakistan Journal of Nutrition Vol: 9(5): pp 485 - 487.
Asekun, O. T., Grierson, D. S. and Afolayan, A. J. (2007). “Effects of Drying Methods on the Quality and Quantity of the essential Oil of Mentha longifolia L. subsp. Capensis”. Food Chem. 101, pp 995–998.
Braga, A. M. P., Pedroso, M. P., Augusto, F., Silva, M. A. (2009). Volatiles Identification in Pineapple Submitted to Drying in an Ethanolic Atmosphere. Drying Technol. 27, pp 248–257.
Consuelo D. M., Soledad P. C. M., Gonzalez V. M. A., and Dolores C. M. (2003).“Influence of Drying on the Flavour Quality of Spear Mint (Mentha spicata L.)”. J. Agric. Food Chem. Vol: 51(5), pp 1265-1269.
Deshmukh A. W., Varma M. N., Yoo C. K. and Wasewar K. L. (2014). “Investigation of Solar Drying of Ginger (Zingiber officinale): Empirical Modelling, Drying Characteristics, and Quality Study”. Hindawi Publishing Corporation Chinese Journal of Engineering, Article ID 305823, 7 pages.
Garba Z. N. and Oviosa S. (2019). “The Effect of Different Drying Methods on the Elemental and Nutritional Composition of Vernonia amygdalina (bitter leaf)”. Journal of Taibah University for Science Vol. 13, No. 1, pp 396–401.
Garti, H., Agbemafle, R., and Ibrahim, A. (2018). “Effects of Shade and Sun Drying on Nutrient Composition of Hibiscus Cannabinus”.UDS International Journal of Development [UDSIJD] Volume 5 No. 2, ISSN: pp 2026-5336.
Iscan G., Kirimer N., Kurkcuoglu M., Can Baser K.H. and Demirci F. (2002). “Antimicrobial screening of Mentha piperita essential oils”.Journal of agricultural and food chemistry. 50(14): pp 3943-3946.
Kalaivani K., and Chitra, D. V. (2013). “Mathematical Modeling on Drying of Syzygium Cumini (L.)”. Int J Agric and Biol Eng, Vol: 6(4): pp 96－103.
Kaya, A., and Aydin, O. (2009). “An Experimental Study on Drying Kinetics of some Mint Leaves. Energ. Convers. Manage. 50, pp 118-124.
Lad P. P, Pachpor N. A, Ghutukade R. D. and Bhagat S. D. (2019). “Analysis of Drying Characteristics of Ginger by different Drying Methods”. Journal of Pharmacognosy and Phytochemistry; Vol: 8(6): pp 1998-2004.
Park, K. J., Vohnikova, Z., and Brod, F. P. R. (2002). “Evaluation of Drying Parameters and Desorption Isotherms of Garden Mint Leaves (Mentha crips L.)”. J. Food Eng. 51, pp 193-199.
Ratti, C. (2001) “Hot Air and Freeze-Drying of High-Value Foods: a review”. J. Food Eng. 49, pp 311-319.
Rohloff, J., Dragland, S., Mordal, R., Andiversen, T. H. (2005). “Effect of Harvest Time and Drying Method on Biomass Production, essential Oil Yield, and Quality of mint (Mentha piperita L.)”. J. Agric. Food Chem. 53(10), pp 4143–4148.
Satyanarayana, A., Giridhar, N., Balaswamy, K., Shivaswamy and Rao D. G. (2001). “Studies on Development of Instant Chutneys from Pudina (Mint, Mentha spicata) and Gongura (Hibiscus sp)”. J. Food Sci. Technol. 38 (5), pp 512-514.
Shalini, Singh J., Samsher, Chandra S., Kumar V., Chauhan N. and Yadav M. K. (2017). “Effect of Moisture Content and Drying Rate on Dried Aonla Shreds during Ambient Storage”. International Journal of Chemical Studies:5(4): pp 362-366.
Shittu, S. K. and Timothy, T. O. (2020). “Study of Drying Characteristics of Baobab (Adansonia digitata L.) Leaves”. Bayero Journal of Engineering and Technology (BJET) Vol.15 No.2, pp17-21 ISSN: 2449 – 0539.
Copyright (c) 2021 FUDMA JOURNAL OF SCIENCES
This work is licensed under a Creative Commons Attribution 4.0 International License.
FUDMA Journal of Sciences