Judul: Karakterisasi Sifat Fisikokimia dan Jumlah Kelompok Bakteri Tahan Garam (Halofilik) pada Tauco Kering Khas Cianjur
Abstrak: Tauco kering merupakan salah satu olahan pangan fermentasi kedelai yang berasal dari Indonesia. Salah satu tauco tertua yang masih eksis di Indonesia yaitu tauco kering Cianjur. Penelitian mengenai tauco kering ini bertujuan mengetahui karakteristik fisikokimia dan jumlah kelompok mikroba (terutama bakteri halofilik) yang bertahan pada tauco kering selama umur simpan 0 hingga 8 minggu setelah produksi pada penyimpanan suhu ruang dan kulkas. Analisis yang dilakukan dalam penelitian ini meliputi analisis fisikokimia (Aw, pH, kadar air, kadar abu, dan kadar garam) dan mikrobiologi (Angka Lempeng Total (ALT), total bakteri dan total bakteri halofilik, isolasi koloni, morfologi koloni, morfologi sel, pewarnaan Gram dan endospora, serta uji katalase). Analisis fisikokimia tauco kering menunjukkan adanya pengaruh lama penyimpanan tauco kering terhadap Aw dan pH yang disimpan pada suhu kulkas, serta Aw yang disimpan pada suhu ruang. Analisis fisikokimia tauco kering dengan pengaruh suhu penyimpanan menunjukkan adanya pengaruh terhadap pH tauco kering yang disimpan selama 4 minggu, serta Aw dan pH yang disimpan selama 8 minggu. Analisis total mikroba secara keseluruhan menunjukkan tidak adanya pengaruh lama penyimpanan dan tidak adanya pengaruh perbedaan suhu penyimpanan tauco kering dengan berbagai suhu dan waktu inkubasi., Semisolid tauco is a fermented soybean food from Indonesia. One of the oldest tauco that still exist is semisolid tauco from Cianjur. This research aims to determine the physicochemical characteristics and total of microbial groups (especially halophilic bacteria) that survive on semisolid tauco during the storage at room and refrigerator temperature. The analyzes carried out in this study included physicochemical (Aw, pH, water, ash, and salt content) and microbiology analysis (Total Plate Count (TPC), total bacteria and total halophilic bacteria, colony isolation, colony and cell morphology, Gram and endospores staining, also catalase test). Physicochemical analysis of semisolid tauco showed that there was an influence of storage time on the Aw and pH stored at refrigerator temperature, as well as the Aw stored at room temperature. Physicochemical analysis with the influence of storage temperature showed that there was an influence on the pH that stored for 4 weeks, as well as Aw and pH stored for 8 weeks. Analysis of total microbial counts showed that there was no influence on storage time and no influence on differences in storage temperature of semisolid tauco at various temperatures and incubation times.
Keyword: tauco kering, tauco Cianjur, bakteri halofilik, analisis fiiskokimia, total bakteri

Judul: The Diversity of Chemical Characteristics of Tauco as Fermented Soybean Paste
Abstrak: Tauco merupakan produk fermentasi kedelai yang diproduksi secara tradisional di Indonesia dan digunakan sebagai bumbu masak. Tauco berupa pasta berwarna coklat, terbuat dari campuran kedelai kuning dan tepung serealia dengan proporsi kedelai yang lebih besar. Bahan difermentasi pada suhu ruang melalui 2 tahap fermentasi, yaitu tahap fermentasi kapang menghasilkan koji dan tahap fermentasi dalam larutan garam, yang mendorong terjadinya fermentasi spontan oleh mikroba alami yang berasal bahan baku dan lingkungan. Tauco memiliki rasa umami dan aroma yang khas yang sangat bergantung dari banyak faktor, diantaranya yaitu komposisi bahan baku dan kondisi fermentasi selama proses produksinya. Informasi mengenai karakteristik kimia produk tauco yang berasal dari berbagai produsen di Indonesia masih terbatas. Penelitian ini bertujuan untuk mengkarakterisasi komposisi kimia produk tauco yang berbeda dan melakukan pemetaan berdasarkan komposisi kimia tersebut melalui analisis multivariat, serta menentukan sampel tauco dengan konsentrasi umami-related amino acids tertinggi. Komposisi proksimat, kadar garam natrium, total gula, total asam, nilai pH, dan total asam amino dianalisis pada 24 sampel tauco yang diperoleh dari 24 produsen di 7 provinsi di Indonesia. Komposisi kimia dan pemetaan secara statistik menunjukkan bahwa sampel tauco dapat dikelompokkan menjadi tauco padat, tauco semi-padat, dan tauco cair. Tauco padat memiliki karakteristik kimia meliputi 29.19 – 35.33% air (basis basah), 10.02 – 22.77% abu, 9.72 – 11.90% protein, 6.98 – 23.38% lemak, 54.69 – 65.21% karbohidrat, 7.13 – 16.90% garam, 11.88 – 27.04% gula, 1.24 – 2.18% asam, dan 11.45 – 17.53% total asam amino (basis kering). Tauco semi-padat memiliki karakteristik kimia meliputi 42.24 – 54.47% air (basis basah), 13.90 – 36.22% abu, 15.14 – 32.61% protein, 0.92 – 13.97% lemak, 33.71 – 68.35% karbohidrat, 10.85 – 24.83% garam, 10.94 – 42.33% gula, 1.30 – 5.43% asam, dan 13.36 – 24.41% total asam amino (basis kering). Sementara itu, karakteristik kimia tauco cair meliputi 56.23 – 68.06% air (basis basah), 17.12 – 73.83% abu, 20.41 – 30.88% protein, 1.30 – 18.89% lemak, 8.47 – 56.51% karbohidrat, 10.73 – 68.44% garam, 4.45 – 29.92% gula, 1.65 – 5.36% asam, dan 14.12 – 24.56% total asam amino (basis kering). Kadar air dalam basis basah menentukan karakteristik ketiga kelompok tauco tersebut. Tauco semi-padat dan tauco cair memiliki kadar protein tertinggi dan dibuktikan dengan kadar total asam amino yang tertinggi pula. Seluruh sampel tauco memiliki pH sedikit asam, berkisar antara 4.38 – 5.91. Glu dan Asp adalah asam amino dominan pada tauco, menyumbang 25 – 40% dari total asam amino. Keduanya merupakan asam amino berasa umami dalam bentuk asam amino bebas atau sering ditemukan sebagai residu dalam peptida umami. Pemetaan berdasarkan profil asam amino (dari hasil analisis komposisi total asam amino), mengungkapkan bahwa satu sampel tauco semi-padat dipetakan terpisah dari 23 sampel lainnya dan sampel ini memiliki kandungan umami-related amino acids (Asp, Glu, Gly, Ser, Thr, Val) pada konsentrasi tertinggi. Sampel ini dapat dipilih untuk penelitian eksplorasi senyawa peptida dari produk fermentasi kedelai, yang mempunyai rasa umami, yang sedang banyak diteliti di dunia.
Keyword: amino acid profiles, chemical characteristic, clustering analysis, fermented soybean paste, tauco

Judul: The Construction of Greedy SVP LLL Algorithm
Abstrak: A lattice is a set of all integer linear combination of a set of linearly independent vectors in ℝ𝑛���. The independent vectors are called bases of lattice. Any lattice can be generated from many bases, and these bases have the same cardinality. In the lattice, the most fundamental and renowned problem is the Shortest Vector Problem (SVP). SVP is a tracking problem of the shortest nonzero vector in a lattice with equivalent bases. In two dimensions, SVP problem has resolved exactly by Gauss’ algorithm. When the lattice dimension is higher than two, A.K. Lenstra, H.W. Lenstra and L. Lovasz gave a LLL algorithm to compute approximation of nonzero shortest vector in the lattice. Reduced bases solution obtained from LLL algorithm still be an approximation and has polynomial running time of arbitrary dimension which large enough. In 1994, Schnoor and Euchner modified this LLL algorithm as a new variant which later was named deep insertion LLL algorithm. This algorithm is a modified version of the LLL algorithm to the terms of the exchange step to improve the accuracy of output of LLL reduced bases and applying it to the subset sum problem. The purpose of this research are: (1) Reconstruct the LLL algorithm and deep insertion LLL algorithm using a geometric approach. (2) Construct a greedy SVP LLL algorithm. (3) Implement the three algorithms in a symbolic programming language, and evaluate them experimentally. A bases ℬ=[𝐛���1,𝐛���2,…,𝐛���𝑛���] in ℝ𝑚��� is called reduced LLL with parameter 𝛿��� if satisfies: (a) |𝜇���𝑗���𝑖���|≤12, for every integer 𝑖���,𝑗��� with 1≤𝑖���<𝑗���<𝑛���. (b)𝛿���‖𝜋���𝑗���(𝐛���𝑗���)‖2≤‖𝜋���𝑗���(𝐛���𝑗���+1)‖2, for 𝑗���=1,2,…,𝑛���−1,where 𝛿��� is a reduced parameter of real numbers with 14<𝛿���<1. The first requirement is the reduced basis 𝛿��� must “nearly orthogonal” and in its computation case, this requirement can be reached out by using the Gram-Schmidt’s orthogonalization. While the second requirement is called exchange step, or used to called as Lovasz condition. By using both of these requirements, then they establish the LLL algorithm. Then, Schnoor and Euchner modify the LLL algorithm based on the requirements of the exchange step called the deep insertion LLL algorithm, where the exchange step is based on the comparison of the projected vector in orthogonal complement [𝐛���1,𝐛���2,…,𝐛���𝑘���−1]⊥ after j-th reduction. To construct greedy SVP LLL algorithm, the requirements of the exchange step is based on purely by comparing norm of lattice 𝐛���𝑗��� with norm lattice 𝐛���𝑖��� for 𝑖���=1,2,3…,𝑗���−1. The process of insertion reduced vector after the exchange step also has done greedily. Then, we calculate the number of arithmetic operation in greedy SVP LLL algorithm for further analysis. The result of our exprimentation for three algorithms on the certain matrix size shows that the running time of the three algorithms increases propotional to the size of the matrix. The result also shows that by using 𝛿���=34 for the LLL algorithm and the deep insertion LLL algorithm, and the greedy SVP LLL algorithm which is a new variant made by using no parameter of 𝛿���, outperform of the other of two previous algorithm in terms of speed with the same output.
Keyword: LLL algorithm, LLL deep insertion algorithm, greedy SVP LLL algorithm