ISSN: 2338-1345 – Vol. 2. (2): 41- 46 (2014) Journal online http://journal.bakrie.ac.id/index.php/APJSAFE 41 Asia Pacific Journal of Sustainable Agriculture Food and Energy (APJSAFE) A Study on Beef Drying Regime towards Sustainable Energy Huy-Bich Nguyen 1,2,* and Hay Nguyen 1,b 1 Faculty of Engineering and Technology, Nong Lam University Ho Chi Minh City, Viet Nam 2 National Key Laboratory of Digital Control and System Engineering - DCSELAB, Viet Nam National University Ho Chi Minh city, Viet Nam *Corresponding author e-mail address: nhbich@hcmuaf.edu.vn Abstract: Beef is one of the popular meat as the daily food in general and beef processing technology might become one of the interesting food processing research in Vietnam. There are many researchers and industrial companies study on how to create and to develop more kind of instant beef in which the beef drying plays as one of the common food using in Vietnam. For this aspect, finding out the suitable drying regime with the reasonable energy source towards the sustainable is highly attraction. This paper presents the different experimental studies on beef drying using hot-air dryer, heat pump dryer and solar dryer. The results proved that solar energy can be used as a sustainable energy source for forced convection dryer to drying beef with high quality and passing the food standard requirements. The drying regime for beef is as 1) temperature drying is 50 0 C, and 2) the time drying is around 7 hours. The RH of beef might reduce from 75% to 36.7% within 7 hours or the RH rate is around 5.5% per hour when using solar dryer. The quality and color of dried-beef are also tested and it is shown that they are well and satisfied the market requirements. Key words: solar dryer; beef processing; dryer; head pump. _________________________________________________________________________________________________ INTRODUCTION Beef in generally and dried beef in particularly is one of the popular daily food in Viet Nam (Tran Thi, 2010). Beef processing technology might become one of the interesting food processing research in Vietnam in which how to optimization beef drying regime has attracted many researchers. Drying is one processing component amongst several processing technology. Beef drying is a simple but efficient food preservation activity and is not a clearly defined technology (regional office, 2010). It is not only single purpose of dehydrating fresh beef for extension of storage under ambient temperatures for many months, but also be one of various processing steps during the manufacture of specific beef products. Due to the low water content, microbial spoilage of the muscle proteins can be safely prevented (Li Jin Goh, 2011; K.J. Chua, 2010). The contents of fresh beef mostly are water which takes account for 72-75%, then protein is about 18.5 – 22%, next is lipid with 2 – 3%, and last ones like glycogen (0.3 – 0.8%), Fe, Ca, Mg, Zn, vitamin B6, E, A, etc (Tran Thi, 2010). The beef drying at present is mostly done under natural conditions by sun exposing (Nguyen, 2013). This basic traditional drying method is also called sun drying, characterized by direct solar radiation and natural air circulation on the product. It is still a popular method in Viet Nam and largely carried out for meat preservation. Pieces of beef are cut to a specific uniform shape that permits the regular and equal drying of whole batches of beef (Fig.1). They are then suspended in the open air or spread on drying trays made of fiber or wire mesh with a wooden or metallic frame (Fig. 2). For sun drying, in particular for the suspension method, the beef is sometimes dipped in salt solution (approx. 14% common salt). This helps to limit microbial growth on the meat surfaces and protects to some extend against insects. However, this method is known to have some certain disadvantages, such as exposure to contamination from sources such as dirt, wind, rain, insects, rodents and birds and even high surface microbial contamination may occur. The other methods like using dryer for beef drying have also been applied but many things need to be clarified and it is not popular right now. They are the drying regime such as drying time and temperature, air speed, drying method etc. suitable for beef drying, the quality of dried beef, and the drying cost.