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Consumers drink coffee not as nutrition source, but as refreshment drink. For coffee consumers who have high tolerance for caffeine, coffee may warm up and refresh their bodies. High caffeine content in coffee beans may cause several complaints to consumers who are susceptible to caffeine. One of the efforts, for coffee market expansion is product diversification to decaffeinated coffee. Decaffeination process is one of process to reduce caffeine content from agricultural products. Indonesian Coffee and Cocoa Research Institute in collaboration with Bogor Agricultural University has developed a single column reactor for coffee beans decaffeination. The aim of this research is to study process characteristic of coffee decaffeination in single column reactor using ethyl acetate (C4H8O2) solvent. Treatments applicated in the research were time and temperature process. Temperature treatment were 50—60OC, 60—70OC, 70—80OC, 80—90OC and 90—100OC. Time treatment were 2 h, 4 h, 6 h, 8 h, 10 h, and 12 h Size of Robusta coffee beans used were less than 5.5 mm (A4), between 5.5 mm and 6.5 mm (A3), between 6.5 mm and 7.5 mm (A2), and more than 7.5 mm (A1). The result showed that decaffeination process with ethyl acetate solvent will be faster when its temperature was higher and smaller bean size. For bean size less than 5,5 mm, decaffeination process by 10% ethyl acetat can be done 8—10 hours in 90—100OC solvent temperature or 12 hours in 60—70OC solvent temperature for 0.3% caffein content. Organoleptic test showed that 90—100OC temperature solvent treatment decreased coffee flavor, which aroma, bitterness and body values were 1.9 each . Key words : Coffee, caffeine, decaffeination, quality, single column.

The secondary process of cocoa is one of the promising alternatives to increase the value added of dried cocoa beans. One the other hand, the development for secondary cocoa process requires an appropriate technology that is not available yet for small or medium scale business. Cocoa roaster is a basic equipment to produce good and competitive secondary cocoa products for chocolate industry. The Indonesian Coffee and Cocoa Research Institute has, therefore, designed and tested a horizontal cylinder type roaster for drying cocoa cotyledon. The cylinder has 405 mm diameter, 520 mm long and is rotated by a 1 HP (0.75 kW), 220 V, single phase and 1400 rpm electric motor. Assisted with a gear reducer, the final cylinder rotation is adjusted at approximately 6 rpm. The heat for roasting process is generated from kerosene burner. At the end of roasting, the roasted beans are cooled down by ambient air inside a cooling platform by natural air flow. The raw material used in this optimizing test was dried fine cocoa cotyledon. Field tests showed that the optimum performance of the roaster was 7 kg dried fine cocoa cotyledon loaded with roasting temperature 120 oC and 25.57 kg/h optimum capacity. The organoleptic test showed that score of aromatic, flavour, acidity, bitterness, astringency and burnt were 4.8, 5.2, 5.4, 5.2, 4.8 and 0.8 with 10 scale, also 4.2 with 5 scale for likely. The roasting time was 15—25 minutes to get 2.5—3% final water content depend on roasting temperature and cocoa cotyledon loaded. Key words: cocoa, roasting, horizontal cylinder, quality.

Indonesian cocoa is cheaper and considered second grade compared with most other cocoa. However, the domestic chocolate industry is not well-developed due to significantly low consumption. To cope with these issues, product innovation through technical process improvement is required to stimulate the domestic chocolate industry. This study aimed to investigate the effect of cocoa bean origin and conching time on the physicochemical (water content, texture, color, crude fat content, and melting enthalpy) and microstructural properties of chocolate. The experiment was conducted under a completely randomized factorial design consisting of two factors: cocoa bean origin (100% fermented cocoa beans from Jember, 100% fermented cocoa beans from Southeast Sulawesi, 50% fermented cocoa beans from Jember + 50% non-fermented cocoa beans from Southeast Sulawesi, and 50% fermented cocoa beans from Southeast Sulawesi + 50% non-fermented cocoa beans from Southeast Sulawesi) and conching time (4, 6 and 8 h). The results showed that cocoa bean origin significantly affected the hardness, gumminess and color of chocolate, including the redness and yellowness level, whereas conching time affected water content, hardness, cohesiveness, elasticity, and crude fat content. Differential scanning calorimetry (DSC) analysis showed that the treatment with 100% fermented cocoa beans from Jember presented higher values of Tonset, ΔHmelt and area compared with those of the treatment with 100% fermented cocoa beans from Southeast Sulawesi, which presented higher values of Tpeak and Tend. Scanning Electron Microscopy (SEM) analysis showed a distribution of solid and dense particles with crystal interaction with chocolate structures.

The NIR spectroscopy for characterization and classification of intact Java arabica coffee beans based on their origin is proposed. Commonly, NIR spectroscopy is used to determine composition of agricultural products including coffee. Three kinds of Java arabica coffee beans namely Arabica Java Preanger, Arabica Bondowoso and Arabica Malang were used in this research. Three hundred samples, each consisted of 100 g coffee beans were prepared. The coffee beans of 100 g were placed in petri dish and the light reflectances of intact coffee beans were measured by FT-NIR spectrometer at the wavelength of 1000-2500 nm. After reflectance measurement, the samples were subjected to composition analysis using proximate and Liquid Chromatography Mass Spectrometry. The reflectance and absorbance spectra were processed by five spectra data pretreatments (smoothing, first derivative, second derivative, Standard Normal Variate (SNV), Multiple Scatter Correction (MSC)) and then Principle Component Analysis (PCA) were carried out. Discriminant analysis (DA) of Principle Components were developed to classify coffee beans based on their origin. The results show that the spectra data treatments of SNV and MSC of reflectance spectra and PC analysis using PC1 and PC2 gave the best results for discriminating three kinds of coffee beans. The DA of three principle components of reflectance data processed by SNV and MSC could classify arabica coffee beans accurately (100%). This results shows that NIR spectroscopy can be used as a nondestructive method to classify arabica coffee beans based on their origin.

A simple mathematic model for caffeine kinetic description during the extraction process (leaching) of coffee bean was developed. A non­steady diffusion equation coupled with a macroscopic mass transfer equation for solvent was developed and them solved analytically. The kinetic of caffeine extraction from coffee bean is depend on initial caffeine content, final caffeine content, caffeine content at certain time, mass­transfer coefficient, solvent volume, surface area of coffee beans, process time, radius of coffee bean, leaching rate of caffeine, caffeine diffusivity and a are constan, solvent concentration, activation energy, temperature absolute and gas constant. Caffeine internal mass diffusivity was estimated by fitting the model to an experiment using acetic acid and liquid waste of cocoa beans fermentation. The prediction equation for leaching rate of caffeine in coffee beans has been found. It was found that Dk (m2/sec)=1.345x10­7—4.1638x10­7, and kL (m/sec)=2.445x10­5—5.551x10­5 by acetic acid as solvent depended on temperature and solvent concentration. The prediction equation for length of time to reduce initial caffeine content to certain concentration in coffee beans has been developed, Caffeine diffusivity (Dk) and mass­transfer coefficient (kL) was found respectively 1.591x 10­7—2.122x10­7 m2/sec and 4.897x10­5—6.529x10­5 m/sec using liquid waste of cocoa bean fermentation as solvent which depend on temperature and solvent concentration. Key words: Coffee, caffeine, decaffeination, leaching, mathematic model.

Dying is one of important steps in coffee processing to produce good quality. Greenhouse is one of artificial drying alternatives that potential for coffee drying method cause of cleans environmental friendly, renewable energy sources and chippers. Indonesian Coffee and Cocoa Research Institute has developed and testing a big scale greenhouse type dryer for fresh coffee cherries and wet parchment coffee drying process. Greenhouse has 24 m length, 18 m width, also 3 m high of the front side and 2 m high of the rear side. The maximum capacity of greenhouse is 40 tons fresh coffee cherries. Fiber Reinforced Plastic (FRP) used as greenhouse roof that combined with I and C profile of steel. Fresh coffee cherries and wet parchment coffee from Robusta variety use as main materials in this research. The treatment of this research was 30 kg/m2, 60 kg/m2 and 90 kg/m2 for coffee density. String process has done by manual, two times a day in the morning and in the afternoon. As control, fresh coffee cherries and wet parchment coffee has dried by fully sun drying method. The result showed that a big scale greenhouse has heat drying efficiency between 29.9-58.2% depend on type and density of coffee treatments. On the full sunny day, greenhouse has produced maximum drying air temperature up to 52oC. In radiation cumulative level 4-5 kW-jam/m2 per day, 12.9-38.8 tons fresh coffee cherries or wet parchment coffee with 58-64% moisture content can be dried to 12% moisture content for 6 up to 14 days drying process. Slowly drying mechanism can be avoided negative effect to degradation of quality precursor compound. Capacity of the dryer can be raise and fungi can be reduce with application of controllable mechanical stirring in the greenhouse. Keywords: greenhouse, coffee, drying, quality

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