Judul: Teknologi Proses Pengolahan Nasi Gurih Instan
Abstrak: Nasi merupakan bahan pangan pokok utama bagi sebagian masyarakat Indonesia. Berbagai variasi pengolahan beras menjadi nasi telah lama berkembang. Salah satu produk yang telah banyak beredar di masayarakat adalah nasi gurih. Nasi gurih instan lebih praktis dalam penyajiannya. Tahapan pengolahan nasi gurih instan meliputi pencucian, perendaman, pemasakan, pembekuan, dan pengeringan. Proses pembekuan dilakukan pada suhu -20 oC selama 24 jam dan 72 jam. Proses pengeringan menggunakan fluidized bed dryer selama 3 jam. Nasi putih instan digunakan sebagai kontrol. Parameter yang dianalisis yaitu karakteristik fisik, karakteristik kimia, karakteristik fungsional, dan penerimaan konsumen. Hasil penelitian nasi gurih instan dengan perlakuan pembekuan 24 jam dan 72 jam tidak berbeda pada karakteristik fisik, penerimaan konsumen dan laju pengeringan. Nasi gurih dengan perlakuan pembekuan 24 jam terpilih karena lebih efisien dari segi waktu dan biaya. Hasil penelitian nasi gurih instan dengan perlakuan pembekuan 24 jam memiliki karakteristik rendemen (95,77%), densitas kamba (0,57 g/mL), waktu rehidrasi (14,34 menit), rasio rehidrasi (2,86), rasio volume pengembangan (2,26), dan daya serap air (69,50%). Nasi gurih instan dengan perlakuan pembekuan 24 jam mengandung kadar air (8,48%), kadar abu (3,93%), kadar lemak (5,56%), kadar protein (7,54%), kadar karbohidrat (82,97%), kadar amilosa (32,39%), kadar amilopektin (46,59%), kadar pati (79,98%), daya cerna pati (54,84%), dan kadar pati resisten (1,90%)., Rice is the main staple food for some Indonesian people. Various variations of processing rice into rice have long been developed. One product that has been widely circulated in the community is savory rice. Instant savory rice is more practical in serving. The stages of processing instant savory rice include washing, soaking, cooking, freezing and drying. The freezing process was carried out at -20 oC for 24 hours and 72 hours. The drying process uses a fluidized bed dryer for 3 hours. Instant white rice was used as a control. The parameters analyzed are physical characteristics, chemical characteristics, functional characteristics, and consumer acceptance. The results of research on instant savory rice with 24 hour and 72 hour freezing treatments did not differ in physical characteristics, consumer acceptance and drying rate. Savory rice with 24 hour freezing treatment was chosen because it is more efficient in terms of time and cost. The research results of instant savory rice with 24 hour freezing treatment had the characteristics of yield (95.77%), bulk density (0.57 g/mL), rehydration time (14.34 minutes), rehydration ratio (2.86), expansion volume ratio (2.26), and water absorption capacity (69.50%). Instant savory rice with 24 hour freezing treatment contains water content (8.48%), ash content (3.93%), fat content (5.56%), protein content (7.54%), carbohydrate content (82.97%), amylose content (32.39%), amylopectin content (46.59%), starch content (79.98%), starch digestibility (54.84%), and resistant starch content (1.90%).
Keyword: functional food, instant rice, resistant starch, savory rice

Judul: Development of Instant Sorghum Rice Product with Two Different Processing Techniques (Parboiled and Conventional)
Abstrak: Nasi sorgum instan merupakan nasi sorgum kering bertekstur porous yang dapat direhidrasi secara cepat menjadi nasi sorgum siap konsumsi. Penelitian ini bertujuan menentukan teknik pengolahan yang mampu menghasilkan nasi sorgum instan yang baik dengan parameter mutu waktu rehidrasi, karakteristik fisik, tingkat penerimaan konsumen, dan Informasi Nilai Gizi (ING) dari produk terpilih. Perendaman biji sorgum untuk teknik parboiled dilakukan dalam water bath bersuhu 60oC (0, 1, 2, 3, 4, 6 jam), dan dianalisis kadar airnya. Penyosohan biji sorgum teknik konvensional dengan abrasive polisher dilakukan pada tiga waktu yaitu 30, 45, dan 60 detik serta dianalisis derajat putihnya. Pengolahan teknik parboiled memiliki tahapan berupa perendaman, pengukusan, pembekuan, pengeringan, dan penyosohan, sedangkan teknik konvensional memiliki tahapan berupa penyosohan, pencucian, pengaronan dengan penambahan gliserol (0%, 2%, 4%), pengukusan, pembekuan, dan pengeringan. Nasi sorgum hasil pengukusan dibekukan pada freezer bersuhu -20oC selama 24 jam dan dikeringkan dengan fluidized bed dryer hingga mencapai bobot konstan. Teknik konvensional lebih baik untuk dikembangkan karena memiliki waktu rehidrasi yang memenuhi kriteria pangan instan, bobot akhir lebih rendah, laju kehilangan air lebih tinggi, dan waktu pengeringan dua kali lebih cepat. Karakteristik fisik produk terpilih meliputi waktu rehidrasi (7,5 menit), densitas kamba (0,4029–0,4136 g/mL), daya serap air (38,91–41,92%), rasio rehidrasi (3,4270–3,5830) dan rasio volume pengembangan (209,1705–223,7180). Pemilihan konsentrasi gliserol 0% dilakukan karena tidak memberikan pengaruh nyata pada produk. Satu sajian nasi sorgum instan (60 g) mengandung energi total (240 kkal), protein 3 g (6% AKG), lemak total 0 g (0% AKG) dan karbohidrat 56 g (17% AKG)., Instant sorghum rice is dry sorghum rice with a porous texture that can be quickly rehydrated into ready-to-eat sorghum rice. This study aims to determine a processing technique that can produce good instant sorghum rice with rehydration time as quality parameter, physical characteristics, level of consumer acceptance, and nutrition facts (ING) of the selected product. Sorghum seeds for the parboiled technique were carried out in a water bath at 60oC (0, 1, 2, 3, 4, 6 hours), and the water content was analyzed. The conventional technique of polishing sorghum seeds with an abrasive polisher was carried out at three times, namely 30, 45, and 60 seconds and the degree of whiteness was analyzed. Processing of the parboiled technique has stages in the form of soaking, steaming, freezing, drying, and polishing, while the conventional technique has stages in the form of polishing, washing, boiling with the addition of glycerol (0%, 2%, 4%), steaming, freezing, and drying. Steamed sorghum rice was frozen in a freezer at -20oC for 24 hours and dried using a fluidized bed dryer until it reached a constant weight. The conventional technique is better to develop because it has a rehydration time that meets instant food criteria, lower final weight, higher water loss rate, and twice as fast drying time. The physical characteristics of the selected product include rehydration time (7,5 minutes), bulk density (0,4029–0,4136 g/mL), water absorption capacity (38,91–41,92%), rehydration ratio (3,4270–3,5830) and volume expansion ratio (209,1705–223,7180). The choice of 0% glycerol concentration was carried out because it did not have a significant effect on the product. One serving of instant sorghum rice
Keyword: Conventional, glycerol, instant sorghum rice, parboiled, rehydration time

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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