Karakterisasi Tepung Beras Menir Kukus Dan Pendugaan Umur Simpannya

Abstract

Rice milling is one of rice post harvest steps to process rice germ into ready consumed rice with by product husk, bran, and menir rice. The increasing of rice production will also increase the by products that is menir rice. Based on Badan Pusat Satistik (2008), rice production in 2008 was 60.28 million tons with yield of menir rice is 2 %. The projection of this amount are 1.2 million tons menir rice, sales in low price. Menir rice has size smaller that 0.2 part of rice or broken rice that pass 1.7 mm screening that could utilized as alternative food source with chemical composition similar with rice. The purpose of this research is to obtain the characteristics of menir rice flour from quality, amount of microbiology, functional characteristics and to found out the self-life of menir rice flour using Arrhenius method. Menir rice from rice milling processed into rice flour through steaming process. The research method separated into two steps, the first step is to obtain menir rice flour with the best treatment using the proximate analysis, flour functional analysis, and microbiology test. The second step is the product self-life testing using analysis of percentage water, total acid, solubility, swelling power, color, hedonic and water retention capacity. This research use 3 levels steaming duration that are 10, 15, and 20 minute. The self-life testing used three storage temperature which are 35, 45, and 50 oC. Drying time for fresh and steamed menir rice is 4 hour in 50 oC temperature drying with composition of menir rice flour are : the water content 11.82 %, ash 0.59 %, protein 7.94 %, fat 2.40 %, fibre 0.61 %, carbohydrate by difference 76.64 %, solubility 10 % and swelling power 14.30 %, apparent viscosity of rice paste decrease with increasing shear rate, water retention capacity fell up into twice maximum increase at two degrees temperature 75 oC and 90 oC, and there is no microbiology in menir rice flour. The proximate analysis and the functional analysis for 3 levels steaming duration that are 10, 15, and 20 minute show that menir rice flour that steamed for 20 minutes had the best characteristics. From functional characteristics of menir rice flour found that 20 minutes steaming duration has a higher viscosity than other level steaming, good in stability of paste, and water retention capacity fell up into maximum increase at 90 oC. The shelf-life for temperature 25 oC approximately 7 month 2 week, using total acid perimeter . Shelf-life for storage in other temperature could be count with the quality decreasing rate which is k amount 1.94 x 10-3 per week. The total acid perimeter used because increasing total acid perimeter made stamed menir rice flour damaged faster than using water content perimeter. The steamed menir rice flour shelf life still on average flour storage which are 6-12 month.