Judul: Phytic Acid Degradation In Jagaq (Setaria italica) Through Cultivation Using R. oligosporus and L. plantarum.
Abstrak: Belakangan ini kementrian pertanian Indonesia sedang menggalakkan program diversifikasi pangan. Salah satu jenis tanaman yang dapat medukung program diversifikasi pangan adalah tanaman jagaq. Tanaman jagaq adalah tanaman sejenis serealia yang mengandung karbohirat tinggi sebesar 70-80% yang berasal dari Kutai Barat, Kalimantan Timur sehingga berpotensi dijadikan tanaman pokok. Namun, seperti serealia lainnya, jagaq mengandung zat anti nutrisi yaitu asam fitat sehingga perlu dilakukan modifikasi pada tepung jagaq dengan metode kultivasi menggunakan kapang Rhizopus oligosporus dan Lactobacillus plantarum. Tujuan penelitian ini adalah mengetahui kandungan asam fitat pada jagaq, mengetahui pengaruh strain mikroorganisme terhadap aktivitas enzim fitase, mengetahui pengaruh variasi lama kultivasi terhadap penurunan kadar asam fitat, mengetahui perbandingan jenis mikroorganisme terhadap penurunan kadar asam fitat dan menentukan rancangan rinci bioreaktor berdasarkan kondisi proses. Hasil penelitian menunjukkan bahwa pemilihan strain mikroorganisme berpengaruh dalam penurunan kadar asam fitat. Lama kultivasi berpengaruh terhadap penurunan kadar asam fitat. Penurunan kadar asam fitat terendah didapatkan pada kapang R.oligosporus dengan perlakuan lama kultivasi 24 jam yaitu 25,15%. Penurunan kadar asam fitat tertinggi didapatkan pada bakteri L.plantarum dengan perlakuan lama kultivasi 48 jam yaitu sebanyak 42,56%. Pemilihan bioreaktor berdasarkan kondisi proses dan jenis mikroba yang digunakan, tipe reaktor yang dipilih reaktor alir tangki berpengaduk atau batch stirred tank reactor dengan pengaturan suhu menggunakan tipe jacket., Recently, Indonesia's ministry of agriculture is promoting a food diversification program. One type of crop that can support the food diversification program is the jagaq plant. Jagaq plant is a cereal-like plant that contains 70-80% high carbohirat which comes from West Kutai, East Kalimantan so that it has the potential to be used as a staple crop. However, like other cereals, jagaq contains anti-nutritional substances, namely phytic acid, so it is necessary to make modifications to jagaq flour by cultivation methods using Rhizopus oligosporus and Lactobacillus plantarum. The purpose of this study is to determine the content of phytic acid in jagaq, find out the influence of microorganism strains on phytase enzyme activity, find out the effect of variations in cultivation duration on reducing phytic acid levels, find out the comparison of microorganism types to decreased phytic acid levels and determine the detailed design of bioreactors based on process conditions. The results showed that the selection of microorganism strains had an effect in reducing phytic acid levels. The length of cultivation has an effect on reducing the level of phytic acid. The lowest decrease in phytic acid levels was obtained in R.oligosporus mold with a 24-hour cultivation duration treatment of 25.15%. The highest decrease in phytic acid levels was obtained in L.plantarum bacteria with a 48-hour cultivation duration treatment of 42.56%. The selection of bioreactors is based on the process conditions and the type of microbes used, the type of reactor chosen by the stirred tank reactor or batch stirred tank reactor with temperature regulation using the jacket type.
Keyword: cultivation, L. plantarum, R. oligosporus, phytic acid

Judul: Perbaikan Tekstur Tepung Jelai (Coix lacryma-jobi L.)  Menggunakan Metode Kultivasi Lactobacillus plantarum. dan Autoclaving-Cooling
Abstrak: Jelai (Coix lacryma-jobi. L.) merupakan salah satu jenis tanaman serealia yang memiliki kandungan protein tinggi dan karbohidrat rendah. Produktivitas tanaman jelai mencapai 8-10 ton/Ha di Daerah Kalimantan Timur. Namun, pembudidayaan jelai sebagai komoditas pertanian di Indonesia dinilai belum merata. Pengaplikasian tepung jelai pada pembuatan produk dinilai masih terdapat kekurangan yaitu masih terdapat bulir bulir halus yang membuat tekstur produk yang dihasilkan sedikit kasar. Dalam hal ini dilakukan penelitian dengan melakukan modifikasi jelai menggunakan kombinasi kultivasi dan siklus autoclaving-cooling. Kultivasi dilakukan menggunakan Lactobacillus plantarum. sedangkan autoclaving-cooling memanfaatkan suhu dalam melakukan pre-gelatinisasi dan retrogradasi. Kedua metode ini menjadi acuan perancangan alat modifikasi jelai dalam skala besar. Hasil penelitian menunjukkan kultivasi 24 jam dan 2 siklus autoclaving-cooling ¬dapat menurunkan suhu dan waktu gelatinisasi pada jelai. Suhu terbaik yaitu 43ºC dengan waktu 32 detik. Bahan konstruksi alat menggunakan stainless steel 304. Rancangan alat modifikasi menggunakan bioreaktor dilengkapi pengaduk propeller untuk kultivasi. Pre-gelatinisasi dilakukan menggunakan rancangan tangki pemanas yang memanfaatkan uap panas yang diumpan dari boiler dengan suhu 100ºC-121ºC. Retrogradasi jelai dilakukan pada suhu 4ºC menggunakan chiller. Modifikasi menggunakan kombinasi kultivasi dan autoclaving-cooling dapat memperbaiki bulir berpasir pada produk dibandingkan dengan control., Barley (Coix lacryma-jobi. L.) is a type of cereal plant that has high protein and low carbohydrate content. Barley productivity reaches 8-10 tons/ha in East Kalimantan. However, the cultivation of barley as an agricultural commodity in Indonesia is considered uneven. The application of barley flour in the manufacture of products is considered to still have shortcomings, namely there are still fine grains that make the texture of the resulting product a little rough. In this case, research was conducted by modifying barley using a combination of cultivation and autoclaving-cooling cycles. Cultivation was carried out using Lactobacillus plantarum. While autoclaving-cooling utilizes temperature to pre-gelatinize and retrograde. Both of these methods become a reference for designing large-scale barley modification tools. The results showed that 24 hours of cultivation and 2 cycles of autoclaving-cooling could reduce the temperature and time of gelatinization in barley. The best temperature is 43ºC with a time of 32 seconds. The tool construction material uses 304 stainless steel. The modified tool design uses a bioreactor equipped with a propeller stirrer for cultivation. Pre-gelatinization is carried out using a heating tank design that utilizes hot steam fed from a boiler with a temperature of 100ºC-121ºC. Barley retrograde was carried out at 4ºC using a chiller. Modification using a combination of cultivation and autoclaving-cooling can improve the grit of the product compared to the control.
Keyword: barley, cultivation, autoclaving-cooling, tools, bioreactor

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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