Judul: Studying the effect of substitution level of different types of flour on the snack extrusion product characteristics
Abstrak: One application of extrusion technology in the field of food processing is the manufacture of snack food (snacks). The raw material is a very role in the quality of extrusion products. Various types of materials substitution in the form of flour was used in this research to study the interaction with the main raw material in the form of particles of corn and its influence on the characteristics of the extruded snack products. The research conducted consisted of two parts, the preliminary research and primary research. Preliminary study aimed to explore the appropriate extrusion process conditions. The determined process conditions is a feed screw speed, extruder screw speed, barrel temperature (T 1, T 2, T 3), and feed moisture content. The primary research is the manufacture of extruded products with substitution treatment consisting of two degree of concentration of three types of flour substitution (5%, 10%). The conducted analysis of the product is water content (before and after drying), texture (hardness), the degree of gelatinization, water absorption index (WAI), water solubility index (WSI), the degree of expansion, bulk density, and organoleptic test (hedonic).
Keyword: 

Judul: Mempelajari Pengaruh Pre-conditioner, Kecepatan Ulir, dan Substitusi Gandum Utuh Terhadap Ekstrusi
Abstrak: Extrusion cooking is the process of forcing a material to flow under a variety of conditions through a shaped hole (die) at a predetermined rate to achieve various resulting products. This research was done to learn the influences of pre-conditioner, screw speed, and whole wheat substitusion in extrusion process.Several extrusion treatments were studied, as follows: pre-conditioner treatment, wheat proportion (0 %, 5 %, and 10 %), and screw speed (350 rpm, 360 rpm, and 370 rpm). Pre-conditioner, wheat proportion, and screw speed found to affect the product in different ways. Pre-conditioning treatment increases the product’s moisture, gelatinisation degree, WSI (Water Solubility Index), WAI (Water Absorbtion Index), hardness and product’s length but it decreases the product’s bulk density. The higher wheat proportion between 0 % to 10 % increases gelatinisation degree, WSI, hardness, and bulk density. On the other hand, increasing of screw speed around 350 rpm to 370 rpm will increases gelatinisation degree, WSI, product’s length, hardness, but decreases product’s expansion degree.
Keyword: 

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf