Effects of Drying Temperature on the Drying Characteristics of Parboiled Palm Nuts

Abstract

The effect of drying temperature on drying characteristics of cooked and fermented palm nuts were determined. The samples were processed using two methods (cooking and fermentation). The rate of drying the samples was observed to increase with corresponding increase in temperature and drying time. It was duly observed that at 70C, Tenera sample (TS), Pisifera sample (PS) and Dura sample (DS) attained their constant drying rates at 720 mins, 600 mins, and 780 mins. At 80C TS, PS and DS drying rates falls to zero at 660mins, 600 mins and 720 mins, for 90C drying temperature, TS and PS had same constant drying rate at 540 mins, DS constant drying rate was found at 600mins. For 100C TS constant drying rates was observed at 480mins while PS and DS had same constant drying rate at 420mins respectively. The effective drying of the samples was observed to occur at falling rate across the varieties and processing methods. The lower temperature (70C) decreased the drying rates while the higher temperature increased the drying rates. The average drying time for cooked samples irrespective of sample varieties were 740 mins, 620 mins, 460 mins and 500 mins for temperature range of 70-100C respectively while for the fermented samples, the average drying time were 680 mins, 660 mins, 560 mins and 440 mins at temperature range of 70-100C respectively. The regression equations were found to give the best fit with highest coefficient of variation (R2) values. Mostly all the samples irrespective of processing methods exhibited quadratic regression equations. The cooked samples displayed better dry characteristics than fermented samples.

Keywords

• Palm nuts
• Drying
• Fermentation
• Cooked
• Temperature

References

1. Akangbe JA, Adesiji GB, Fakayode SB and Aderibigbe YO (2011). Towards palm oil self-sufficiency in nigeria: constraints and training needs nexus of palm oil extractors. Journal of Human Ecology, 33(2): 139-145.
2. Akpinar EK, Midilli A and Bicer Y (2003). Etperimental investigation of drying behavior and conditions of pumpkin slices via a cyclone-type dryer. Journal of Food Science and Agriculture, 83: 1480-1489.
3. Alonge AF (2008). A study of drying rate of some fruits and vegetables with passive solar dryers. American Society of Agricultural and Biological Engineers-Food Processing Automation Conference 2008, p. 98-111.
4. Alonge AF and Hammed RO (2007). A direct passive solar dryer for tropical crops. African Crop Science Conference Proceedings, 8: 1643-1646.
5. Amer BMA, Hossain MA and Gottschalk K (2009). Design and performance evaluation of a new hybrid solar dryer for banana. Journal of Energy Conversion and Management, 51(4): 813-820.
6. Barcelos E, de Almeida Rios S, Cunha RNV, Lopes R, Motoike SY, Babiychuk E, Skirycz A, Kushnir S (2015). Oil palm natural diversity and the potential for yield improvement. Frontiers Plant Science, 6:190.
7. Brennan, J. G. (2006). Evaporation and Dehydration. In: Food Processing Handbook, Brennan, J.G. (Ed.). Wiley-VCH Verlag, GmbH and Co., Weinheim, Germany, p. 71-121.
8. Chineze GO, Brendan E and Eze CE (2020) Drying characteristics of yam varieties: A comparative analysis. University of Belgrade Faculty of Agriculture, Institute of Agricultural Engineering Scientific Journal Agricultural Engineering, 1: 20-37.

9. Conway J (2018). Nigeria's palm oil consumption 2011/12-2018/2019. Available online at https://www.statista.com/statistics/489451/palm-oil-consumption-nigeria/
10. Corley RHV and Tinker PB (2007). The Oil Palm (4th ed) edited. Blackwell Science Ltd, 561 p.
11. Coumans, WJ (2000). Models for drying kinetics based on drying curves of slabs. Chemical Engineering and Processing, 39: 53-68.
12. Dai JW, Qin W, Wu ZJ, Zhang P and Zhang LH (2017). Drying characteristics and quality of yam slices of different thickness during microwave intermittent drying. Advances in Engineering Research, 136: 183-188.
13. Dairo OU and Olayanju TMA (2012) Convective thin-layer drying characteristics of sesame seed. International Journal of Engineering Research in Africa, 7: 55-62. https://doi:10.4028/www.scientific.net/JERA.7.55.
14. Doymaz I (2011). Thin-layer drying characteristics of sweet potato slices and mathematical modeling. Heat and Mass Transfer, 47: 277-285.
15. Embrandiri A, Singh RP, Ibrahim HM and Ramli AA (2011). Land application of biomass residue generated from palm oil processing: its potential benefits and threats. Springer Science. Environmentalist. https://doi.10.1007/s 10669-011-9367-0.
16. Folaranmi J (2009). Design, construction and testing of simple solar maize dryer. Leonardo Electronic Journal of Practices and Technologies, 13: 122-130.
17. Gatea AA (2010). Design, construction and performance evaluation of solar maize dryer. Journal of Agricultural Biotechnology and Sustainable Development, 2(3): 039-046.
18. Hii CL, Law CL and Cloke M (2008). Modelling of thin layer drying kinetics of cocoa beans during artificial and natural drying. Journal of Engineering Science and Technology, 3(1): 1-10.
19. Ibitoye OO, Akinsortan AO, Meludu NT and Ibitoye BO (2011) Factors affecting oilpalm production in Ondo state of Nigeria. Journal of Agriculture and Social Research (JASR), 11: 97-105.
20. John OO, Clinton EO, Adeyi J, Oladayo A, Abiola FOE, Adeniyi G and Olayanju T (2020). Drying characteristics of yam slices (Dioscorea rotundata) in a convective hot air dryer: Application of ANFIS in the prediction of drying kinetics, Heliyon, 6(3): e03555.
21. Kajuna STAR, Silayo VCK, Mkenda A and Makungu PJJ (2001). Thin-layer drying of diced cassava roots, African Journal of Science and Technology: Science and Engineering Series, 2(2): 94-100.
22. Koyuncu T (2005). An investigation on the performance improvement of greenhouse-type agricultural dryers. Journal of Renewable Energy, 31(7): 1055-1071.
23. Maskan, M. (2001). Kinetics of color change of kiwifruits during hot air and microwave drying. Journal of Food Engineering, 48: 169-175.
24. Mujumdar AS and Law CL (2010). Drying technology: Trends and applications in post-harvest processing. Food and Bioprocess Technology, 3: 843-852.
25. Ndukwu MC (2009). Effect of drying temperature and drying air velocity on the drying rate and drying constant of cocoa bean. Agricultural Engineering International: CIGR EJournal., Manuscript 1091.Volume TI.
26. Nguyen MH and Price WE (2007). Air-drying of banana: Influence of experimental parameters, slabthickness, banana maturity and harvesting season. Journal of Food Engineering, 79(1): 200-207.
27. Oduro I, Ellis WO, Sulemana A and Oti-Boateng P (2007). Breakfast meal from breadfruit and soybean composite. Discovery and Innovation, 19: 238-242.
28. Onoh PA and Peter-Onoh CA (2012). Adoption of ımproved oil palm production technology among farmers in Aboh Mbaise local government area of Imo State. International Journal of Agriculture and Rural Development, 15(2): 966-971.
29. Saeed IE, Sopian K and Zainol AZ (2008). Drying characteristics of Roselle (I): Mathematical modeling and drying experiments. Agricultural Engineering International: the CIGR E-journal. Manuscript, 10: 1-25.
30. Sobukola OP and Dairo OU (2007). Modeling drying kinetics of fever leaves (Ocimen viride) in a convective hot air dryer. Nigerian Food Journal, 25(1): 145-153.
31. Stephen KA and Emmanuel S (2009). Modification in the design of already existing palm nut-fibre Separator. African Journal of Environmental Science and Technology, 3(11): 387-398.
32. Zhao J, Wang AJ and Fan TW (2016). Microwave vacuum freeze-drying of yam chip preparation. Journal of Food Science and Technology, 5(27): 89-91.