IJSRST1845508 | Received : 20 April 2018 | Accepted : 30 April 2018 | March-April-2018 [ (4) 5 : 1848-1851] © 2018 IJSRST | Volume 4 | Issue 5 | Print ISSN: 2395-6011 | Online ISSN: 2395-602X Themed Section: Science and Technology 1848 Drying Characteristics of Spinach in Tray dryer and Hot air oven B. Bhavani 1 ,V. Bhasker 2 ¹Post Graduate Student ,Department of Food Technology, University College of Technology (A), Osmania University, Hyderabad, Telangana, India ²Assistant Professor , Department of Food Technology, University College of Technology (A), Osmania University, Hyderabad, Telangana, India ABSTRACT In the present work, spinach samples were dried using two different drying techniques namely tray drying and hot air oven drying. Drying experiments were conducted using a constant air velocity but varying temperature i.e, 60°C and 70°C. Then after 30 minutes the weight of the samples were recorded up to 3 hours and moisture ratio was calculated. It was observed that drying rate enhanced in case of tray drying compared to hot air oven drying with lower drying time. Keywords: Drying rate, Moisture ratio, Tray drying, Hot air oven drying. I. INTRODUCTION Drying (dehydrating) food is one of the oldest and easiest methods of food preservation. Dehydration is the process of removing water or moisture from a food product. Removing moisture from foods makes them smaller and lighter. Dehydrated foods are ideal for backpacking, hiking, and camping because they weigh much less than their non-dried counterparts and do not require refrigeration. Drying food is also a way of preserving seasonal foods for later use. Drying, in which the water content and activity are decreased, is an important method of preservation and production of a wide variety of products. This method brings about substantial reduction in weight and volume, minimizing packaging, storage and transportation costs, and enables storability of the product under ambient temperatures (Baysal et al. 2003). Foods can be spoiled by micro-organisms and through enzymatic reactions within the food. Bacteria, yeast, and molds must have a sufficient amount of moisture around them to grow and cause spoilage. Reducing the moisture content of food prevents the growth of these spoilage causing micro-organisms and slows down enzymatic reactions that take place within food. The combination of these events helps to prevent spoilage in dried food. Spinach (Spinacia oleracea L.) is a flowering plant in the family Amaranthacea native to central and southwestern Asia. It is an important leaf vegetable now grown throughout the temperate regions of the world. It is a rich source of iron, magnesium and potassium and extraordinarily high in vitamins C, A, E, B6 and thiamine (Wikipedia Encyclopedia 2007). Spinach is widely used in making various foods like puree, soups and baked products (Baigai and Hashinaga 2001). Spinach is the one that rapidly perishes after harvest, which is consumed only in the product season. Like other leafy greens spinach has high water content. Drying is one of the preservation methods that has the