Empirical Modeling on Hot Air Drying of Fresh and Pre-treated Pineapples Yardfon Tanongkankit, Kanjana Narkprasom and Nukrob Narkprasom MATEC Web of Conferences, 62 (2016) 02007 Published online: 28 June 2016 DOI: 10.1051/matecconf/20166202007