Judul: Proses Pembuatan Functional Drink dari Ekstrak Kulit Kopi
Abstrak: Kulit kopi memiliki potensi sebagai bahan baku berbagai produk dikarenakan adanya kandungan senyawa aktif seperti tanin, pektin, kafein, asam klorogenat, dan antosianin. Salah satu potensi kulit kopi adalah diolah menjadi minuman fungsional yang bermanfaat untuk kesehatan. Tujuan dari penelitian ini adalah mengembangkan minuman fungsional ekstrak kulit kopi dengan mengetahui kadar proksimat kulit kopi, menentukan proses ekstraksi terbaik dengan rendemen dan aktivitas antioksidan tinggi serta membandingkan minuman fungsional ekstrak kulit kopi tanpa dan dengan lemon. Penelitian dilakukan dengan analisis proksimat, ekstraksi kulit kopi, pembuatan functional drink, dan uji organoleptik. Analisis proksimat kulit kopi menunjukkan kadar air sebesar 2,237%, kadar lemak 7,033%, kadar abu 4,033%, kadar protein 11,196%, kadar karbohidrat 25,637%, dan kadar serat kasar 39,894%. Ekstrak kulit kopi terbaik diperoleh dengan bantuan enzim selulase dan pektinase dengan rendemen sebesar 23,50% dan aktivitas antioksidan sebesar 1,21 µg/ml. Hasil uji organoleptik menunjukkan minuman fungsional ekstrak kulit kopi dengan penambahan ekstrak lemon adalah produk terbaik dari penelitian ini., Coffee cherry skin has the potential to be used as a raw material for various products due to the content of active compounds such as tannins, pectin, caffeine, chlorogenic acid and anthocyanins. One of the potentials of coffee cherry skin is to be processed into a functional drink that is beneficial for health. The purpose of this research is to develop a functional drink from coffee skin extract by determining the proximate content of coffee skin, identifying the best extraction process with high yield and antioxidant activity, and comparing the functional drink made from coffee skin extract with and without lemon. The research was conducted through proximate analysis, coffee skin extraction, functional drink formulation, and sensory evaluation. Proximate analysis of coffee skin revealed a moisture content of 2,237%, fat content of 7,033%, ash content of 4,033%, protein content of 11,196%, carbohydrate content of 25,637%, and crude fiber content of 39,894%. The best coffee skin extract was obtained using cellulase and pectinase enzymes, with a yield of 23,50% and antioxidant activity of 1,21 µg/ml. Results from the sensory evaluation indicated that the functional drink made from coffee skin extract with added lemon extract was the best product from this research.
Keyword: functional drink, coffee skin, extraction, enzyme

Judul: Market Development Strategy  and Determination of Cost of Production Coffee Skin Extract and Its Potential as  a Functional Drink
Abstrak: Indonesia merupakan salah satu negara produsen kopi terbesar di dunia yang ikut memberikan kontribusi terhadap perekonomian negara. Kopi menghasilkan sekitar 50% kulit kopi yang sejauh ini belum banyak dimanfaatkan. Belift Green Beans adalah salah satu perusahaan yang bergerak dalam bidang agroindustri kopi di Indonesia yang sejauh ini hanya membuang kulit kopi yang masih memiliki banyak kandungan bermanfaat yang dapat dimanfaatkan sebagai antioksidan. Penelitian ini bertujuan mengolah kulit kopi menjadi ekstrak kulit kopi dan functional drink. Lean canvas menjadi bentuk awal model bisnis dari lini pengolahan kulit kopi karena lebih cocok diterapkan pada industri yang baru berdiri. Analisis SWOT juga menunjukkan bahwa strategi stabilisasi menjadi fokus utama dalam upaya pengembangan bisnis lini pengolahan kulit kopi tersebut. Strategi stabilisasi itu sendiri yakni seperti pengembangan pasar dan kualitas produk. Alternatif strategi pengembangan pasar yang telah dihasilkan pada penyusunan matriks SWOT juga dapat diterapkan. Pada penelitian ini produk yang direncanakan adalah ekstrak kulit kopi kemasan jerigen food grade kapasitas 20 l dengan harga pokok produksi Rp 64.891/unit dan functional drink kemasan botol food grade kapasitas 250ml Rp 5.062/unit., Indonesia is one of the largest coffee producing countries in the world that contributes to the country's economy. Coffee produces about 50% of coffee skin waste that has so far not been widely utilized. Belift Green Beans is one of the companies engaged in the coffee agroindustry in Indonesia which so far only disposes of coffee skin waste which still has many beneficial ingredients that can be used as antioxidants. This study aims to process coffee skin waste into coffee skin extract and functional drinks. Lean canvas is the initial form of business model of the coffee skin processing line because more suitable for newly established industry. SWOT analysis, also show that stabilization strategy is the main focus for coffee skin processing line business development efforts. The stabilization strategy is like market development and product quality. Alternative market development strategies that have been produced in the preparation of the SWOT matrix can also be applied. In this study, the planned products are coffee skin extract, food grade jerry cans with capacity of 20 ls with a cost of production is IDR 64,981/unit and functional drinks packaged in food grade bottles with a capacity of 250ml is IDR 5,062/unit.
Keyword: Coffeeskin extract, functional drink, cost of production

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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