This study aims to determine the effect of roasting temperature on chemical content of coffee beans at various fruit maturity. Robusta coffee was obtained from Karawang Regency, West Java. After picking, sortation, and drying in the sun to 10% moisture content, the coffee beans were roasted at 190°C, 200°C, 210°C for 12 minutes. Physical properties observed were weight loss during the roasting. The chemical content observed were water, caffeine, fat, chlorogenic acid and ash before and after roasting. Chemical content analysis was performed using gravimetric methods, soxhlet extraction, and UV-Vis spectrophotometry. The color, aroma and flavor of roasted bean were conducted by organoleptic test. The results obtained, the ripe coffee bean with roasting temperature of 210°C is the best, which gives the lowest yield. The unripe green beans have the highest water content. The roasting temperature did not provide a significant difference in fat, caffeine, chlorogenic acid, and ash content. Organoleptic test results (color and aroma) showed that the mature beans with roasting temperature of 200-210°C were the most preferred, while the coffee brew most preferred was overripe bean with the roasting temperature of 200°C.

Coffee is an important export commodity for Indonesia. Coffee drying is post-harvest processing that greatly determines the coffee quality and microbiological safety. Conventional/sun drying is time-consuming, depending on the weather, and can potentially contaminate coffee beans by dust and moisture readsorption under high relative humidity. These problems could be avoided by employing artificial drying. This literature review aims to identify the current status of coffee drying technology, its advantages and limitations, to obtain coffee beans with the desired quality, duration of drying time, and energy consumption for processing. From the three types of thermal radiation dryers being reviewed, namely tray dryer, rotary dryer, and fluidized bed dryer, it was concluded that the drying air temperature and relative humidity must be selected properly to obtain the microbiological safety and the quality of the coffee brew. Efficient energy consumption requires a balance between the rate of water evaporation inside the coffee grain and the rate of water vapor removal from the solid surface by the air stream. The most efficient coffee drying is achieved at an air temperature of 50 o C, resulting in drying time and energy consumption of 65%, and 50% lower than that of 40 o C, with a good quality of the coffee brew. Fluidized bed drying combined with zeolite adsorption is potential to reduce the drying time due to an enhancement of air capacity to absorb water vapor. Application of microwave for coffee drying resulting in much shorter drying time than conventional thermal drying, but has a drawback of un-uniform grain temperature. A hybrid drying system could be implemented by using microwave and thermal oven.

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Polypropylene is a widely used material for various types of equipment. As a recyclable thermoplastic polymer, polypropylene composite provides an attractive quality of thermal insulation due to its heat-retaining property. The use of rice straw for filler in thermal insulating material is based on its low thermal conductivity, renewable material, and low cost production techniques. The composite were manufactured by melt-mixing of neat polypropylene and filler of various weight fractions, pellet formation, followed by reprocessing with injection molding. The current work focused on determining the effect of filler’s weight fraction, particle size and pretreatment on the thermal conductivity and tensile strength of the composite. The result showed that an increase of filler’s weight fraction up to 30% decreased the composite’s thermal conductivity and tensile strength gradually. Composite of fine particles filler (325 mesh) gave a lower thermal conductivity and higher tensile strength than that of coarse particle (18-35 mesh). Composite with the lowest thermal conductivity of 1.39 W/mK was obtained at 30 w.% filler content and fine particles filler (325 mesh). Improvement on composite properties achieved by acetylated rice straw which enable to reduce straw’s hydophylicity and enhance adhesion between matrix and filler.

Palm oil is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of the oil palm, primarily the African oil palm Elaeis guineensis. Oil palm is one of agriculture comodity that can increase farmers income, provide raw material on manufacture industry which can create added value.  The expansion of oil palm farming in Indonesia has shifted the use of mineral land to suboptimal land which is currently available in many place in Indonesia. Generally the aim of this research is to anylize the competitiveness sensitivity of oil palm farming. Specifically this research wants to anylize the sensitivity on input-output changing, and to anylize the impact of government policy on input-output when facing fluctuation price. In order to reach the goal of this research we used Policy Anlayisis Matrix (PAM). The result of this research shows that partially the declining of price, declining of output volume and increasing input price PCR value and DRCR < 1, which means that the oil palm farming on suboptimal land has competitivenes, and the absence of government policy on determaining input price nor output price on oil palm farming in at suboptimal land. While simultanously shows that the fluctuation of input and output price causes value of PCR dan DRCR  > 1 with PCR value 1,12 and DRCR value 1,04, means that oil palm farming on suboptimal land at Musi Rawas Regency not feasible and has no competitiveness.  It means that government policy needed to protect input price in oil palm farming on suboptimal land.  Therefore government support and guidence in oil palm farming technology on suboptimal land also needed to increase the production of oil palm farming on suboptimal land.