Judul: Karakterisasi dan Analisis Kluster Tepung Singkong Terfermentasi Varietas Indonesia
Abstrak: Indonesia has various types of cassava with different physicochemical characteristics. Cassava can be processed into fermented cassava flour (FCF), which is an intermediate cassava-based product used as a raw material in food industries. To enhance the database of cassava varieties in Indonesia, this study aimed to characterize the chemical composition and pasting profiles of FCF produced from 28 different Indonesian cassava varieties. The FCF samples were analyzed in terms of chemical composition (moisture, ash, protein, fat, carbohydrate, starch, amylose, amylopectin, and cyanide content) and their pasting properties (peak viscosity, hot paste viscosity, breakdown viscosity, final viscosity, setback viscosity, pasting temperature, peak time, and gel strength). The chemical composition data were subsequently analyzed using Principal Component Analysis (PCA) and Agglomerative Hierarchical Clustering (AHC). This research discovered that the 28 cassava varieties had a significant effect on moisture, ash, protein, fat, carbohydrate, starch, amylose, amylopectin, cyanide content, and gel strength (p<0.05). The highest productivity value of cassava was in UK 1. However, when combined with the FCF yield, the most efficient variety for FCF production was Barokah. The most potential cassava variety in FCF production had high cyanide and ash content that exceeded SNI. Thus, further decreasing method is needed. A decrease in ash content is needed for UK1, Darul Hidayah, Manggu Bogor, and Kubar B, while a decrease in cyanide content is needed for Barokah, Gajah B, Randu, and Genjah Bayam. Some varieties were potential for tapioca raw material, namely UK 1, Barokah, and Malang 4. The result of pasting properties showed a relatively wide range of each parameter, indicating a potential wide range of food application. The PCA of chemical composition visualized the relationships and similarities among the different cassava varieties based on their ash, starch, amylose, amylopectin, and cyanide content. Based on the same factors, three clusters of FCF were identified: the first cluster had the lowest level of ash, starch, and amylopectin content but has the highest amylose and cyanide content; the second cluster displayed demonstrated the highest ash content and the lowest cyanide content, and the last cluster exhibited the highest levels of starch, amylopectin, but intermediate ash, amylose, and cyanide content. These findings successfully identified cassava varieties with a potential application as a food ingredient., Indonesia memiliki berbagai jenis singkong dengan karakteristik fisikokimia yang berbeda-beda. Singkong dapat diolah menjadi tepung singkong terfermentasi atau fermented cassava flour (FCF) yang merupakan produk antara untuk bahan baku industri makanan. Untuk meningkatkan data varietas singkong di Indonesia, penelitian ini mengkarakterisasi komposisi kimia dan sifat pasta pada FCF yang dihasilkan dari 28 varietas singkong berbeda yang ada di Indonesia. Sampel FCF dianalisis kandungan kimianya (kadar air, abu, protein, lemak, karbohidrat, pati, amilosa, amilopektin, dan sianida) dan sifat pasta (viskositas puncak, viskositas jatuh, viskositas pasta panas, viskositas akhir, viskositas balik, suhu pasting, waktu puncak, dan kekuatan gel). Data komposisi kimia selanjutnya dianalisis menggunakan Principal Component Analysis (PCA) dan Agglomerative Hierarchical Clustering (AHC). Penelitian ini memperlihatkan bahwa 28 varietas ubi kayu berpengaruh signifikan terhadap kadar air, abu, protein, lemak, karbohidrat, pati, amilosa, amilopektin, sianida, dan kekuatan gel (p<0,05). Nilai produktivitas umbi singkong tertinggi ada di
Keyword: cassava, characterization, cluster, fermented, flour

Judul: Physicalization-Chemical Flour and Cassava-Based Noodles from Kalimantan and Bogor
Abstrak: Singkong (Manihot esculenta) merupakan salah satu tanaman yang banyak dibudidayakan di Indonesia, dan termasuk sumber karbohidrat terbesar selain beras. Singkong biasanya diolah dengan digoreng maupun direbus. Penelitian mengenai tepung singkong sudah banyak tetapi untuk singkong dari varietas Pacar dari Kalimantan masih sedikit, dan belum ada penelitian mi yang berasal dari tepung singkong ini. Penelitian ini bertujuan mengkaji karakteristik tepung singkong yang dihasilkan dari singkong varietas Pacar dari Kalimantan dan singkong varietas Manggu dari Bogor, serta mendapatkan karakteristik fisiko-kimia mi berbahan dasar tepung singkong yang didapatkan dari proses penelitian sebelumnya. Penelitian ini dilakukan dengan dua tahapan yaitu proses pembuatan tepung singkong dengan metode pengeringan yang berbeda dan tahapan proses pembuatan mi singkong dengan metode kalendering. Metode analisis yang dilakukan antara lain analisis proksimat, analisis serat, analisis fisik (derajat keputihan, bentuk granula pati, cooking loss, texture profile, dan gelatinisasi pati). Berdasarkan hasil analisis fisik, tepung dengan perlakuan terbaik adalah tepung singkong varietas Pacar dari Kalimantan dengan perlakuan sinar matahari, dan tepung singkong varietas Manggu dari Bogor dengan perlakuan oven. Berdasarkan hasil analisis fisiko-kimia, formulasi terbaik mi singkong diperoleh dengan penggunaan 100% tepung singkong varietas Pacar dengan penambahan glukomanan sebesar 8% dan xanthan gum sebesar 4%., Cassava is one of the most cultivated plants in Indonesia, which is one of the largest sources of carbohydrates besides rice. Cassava is usually processed by frying or boiling. Research on cassava flour has been a lot but for cassava from the Pacar variety from Kalimantan is still a little in Indonesia, as well as research on noodles derived from its cassava flour. This study aims to examine the characteristics of cassava flour produced from cassava variety from Kalimantan and cassava variety Manggu from Bogor, as well as to get the physical-chemical characteristics of cassava noodle made from cassava flour obtained from the previous research process both cassava. This research was conducted with two stages, namely the process of making cassava flour with different drying methods and the stages of the cassava noodle making process with the calendaring method. The analytical methods carried out include proximal analysis, fiber analysis, physical analysis (degree of vaginal discharge, granule shape of starch, cooking loss, texture profile, and gelatinization of starch). Based on the results of physical analysis, the flour with the best treatment is cassava flour from Kalimantan with sunlight treatment, and Cassava flour manggu variety from Bogor with oven treatment. Based on the results of physical-chemical analysis, the best formulation of cassava noodles is obtained with the use of 100% cassava flour of the Pacar variety with the addition of glucomannan by 8% and xanthan gum by 4%.
Keyword: Cassava Flour, Cassava Noodles, Drying, Gelatinization, Physical  Analysis

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model