Stabilisasi Tepung Bekatul dengan Metode Pemanasan Bertekanan dan Pengeringan Rak serta Pendugaan Umur Simpannya.

Abstract

The national production of the unhulled rice on 2007 reported about 60,3 million tons (BPS,2008). The by product is about 12,1 million tons hull, 1,8 million tons broken rice, and 6 million tons bran. For this time bran is used as feed for breed animals and as medium to grow fungi, even though the bran is a potential source of phytochemical materials. The bran contain some of vitamin, minerals, and other nutrition that is necessary to keep human health. The problem is the bran contain many enzymes, especially lipase that can trigger rancidity process in the bran if they don’t be handled well. One of the tech to solve this problem is using pressed steaming. The purpose of this research is to obtain characteristic of the fresh bran, the time of stabilization with pressed steaming and predict storage time of stabilized bran. The fresh bran characteristics include the water level 11,30 %, protein 14,41 %db, fat 18,99 %db, crude fibre 7,25 %db, carbohydrate 46,06 %db, ash 7,8%db, and TBA 1,36 mg malanoldehid/kg of sample. The fresh bran then stabilized by using pressure of heating method (autoclave). Time of process that is used are 5, 10, 15 minutes and dried during 4 hours. Stabilized bran with heating process at 5 minutes was decided as material for predicting of storage time with characteristic of water level 4.94 % and TBA value 0.11 mg malanoldehid/kg of sample. The low of water level can inhibit destruction of the bran and the low of TBA value showed the little action of destruction of the bran. During the storage, the water level and the brightness of the bran has been decreased, mean while TBA value has increased as same as the storage time. The bran is packed by using metallized material and be storaged in the incubator at 35oC, 45oC, and 50oC during 8 weeks. The critical point of this analysis is based on the TBA value. TBA value is opted as the critical point because of can be used as indicator of the succeed factor of stabilization, that showed rancidity indicator. Critical point of TBA value is based on odor test, the value is 0,36 malanoldehid/kg of sample. The Arrhenius equation for the storage is k = 25,1033 e-2092/T. The storage time of the bran at temperature storage 15°C is 9 weeks, 25°C is 7 weeks, and 30°C is 6 weeks 2 days.