Electronic Theses and Dissertation

Penelitian ini dilakukan untuk mengetahui pengaruh metode pengolahan pasca panen terhadap sifat fisis mencakup kadar air, densitas dan porositas serta sifat kimiawi berupa kadar abu dan perubahan gugus fungsi pada biji kopi Arabika dari Gayo. Pengukuran sifat fisis dan kadar abu mengikuti standar SNI-01-2907-2008, dan perubahan gugus fungsi diamati menggunakan FTIR. Berdasarkan pengukuran didapatkan kadar air biji kopi green bean memiliki kadar air tertinggi pada jenis Premium yaitu sebesar 10% dan nilai terendah pada jenis Full Wash yaitu 7%. Pengukuran kadar air setelah proses roasting didapatkan relatif mendekati nol. Secara umum densitas biji kopi green bean lebih kecil dibandingkan densitas biji kopi roasted bean, sedangkan sebaliknya untuk nilai porositas. Kadar abu untuk biji kopi green bean tertinggi pada jenis Specialty yaitu 11% dan terendah pada jenis Luwak yaitu 6,4%, sedangkan untuk biji kopi roasted bean yang tertinggi pada jenis Premium yaitu 11,3% dan terendah pada jenis Natural sebesar 8,6%. Perubahan gugus fungsi terlihat dari perubahan %Transmitansi dan kawah yang berbeda. Berdasarkan penelitian dapat disimpulkan bahwa perbedaan metode pengolahan pasca panen mempengaruhi sifat fisis dan kimia dari jenis biji kopi serta proses pemanggangan menyebabkan perubahan pada kandungan kimianya.

This study was conducted to determine the effect of post-harvest processing methods on physical properties including moisture content, density and porosity as well as chemical properties such as ash content and changes in compounds in Arabica coffee beans from Gayo. Measurement of physical properties and ash content followed the standard of SNI-01-2907-2008, and changes in compounds were observed using FTIR. Based on the measurements, the water content of green bean coffee beans has the highest water content in the Premium type, which is 10%, and the lowest value in the Full Wash type, which is 7%. Measurement of moisture content after the roasting process is obtained relatively close to zero. In general, the density of green beans is smaller than that of roasted beans, while the opposite for the porosity value. The ash content for green beans is the highest for the Specialty type, which is 11%, and the lowest for the Luwak type, which is 6.4%, while the highest for roasted beans is for the Premium type, which is 11.3% and the lowest is for the Natural type, which is 8.6%. Changes in compounds can be seen from changes in %transmittance and different craters. Based on the research, it can be concluded that differences in post-harvest processing methods affect the physical and chemical properties of the type of coffee beans and the roasting process causes changes in the chemical content.