Judul: Pembuatan Minuman Instan Sari Kurma (Phoenix dactylifera)
Abstrak: Palm dates are the fruit that is rich in calories and nutrition. It contains simple sugars, minerals and vitamins, and has potentially function as healthy food. Nowdays dates usually consumed directly as fresh or dried forms, or processed into ready to drink dates extract or concentrate. This research explored the process of making dry instant dates by using spray dryer, formulation of instant drink and examined it’s the characteristics as instant beverages and it’s consumer acceptance. Dried palm dates were used in the research, therefore for preparation of dates extract should be extracted and diluted in hot water. About 50-60% of dextrin and maltodextrin were added as bulking agent for spray drying. Fifty percents of cane sugar powder was added in the formulation of dates instant drink, to increase the sweetness of product. The results shows that sugars (94.31%) is main component in dried dates. Sixty percents of maltodextrin gave the best result in the preparation of spray dried instant dates. The product has high solubility (97.49%) and low viscosity (18.49 cP) with clear or transparant performance. Base on organoleptic test, this product is preffered in terms of taste, color, aroma and solubility.
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Judul: Optimasi Proses Pengeringan Semprot dan Formulasi Minuman Instan Fungsional Ekstrak Kulit Buah Manggis (Garcinia mangostana L.) dengan Teknologi Effervescent.
Abstrak: Mangosteen (Garcinia mangostana L.) is one of world most famous tropical fruits by its unique flavors and aromas. Newest researches reveal that within the extract of mangosteen pericarp contains many kinds of bioactive compounds. Some researches have proved that the extract of mangosteen rind had beneficial properties such anti-oxidant, anti-microbial, cancer prevention, etc. Considering the advantages, many food product based on the mangosteen extract, especially “ready to drink product” was developed. Nevertheless, there are problems occurs specially dealing with the stability of the product during storage. Consider as watery based product, the bioactive compounds containing within the product are easily degrading during several periods of storage. To solve that stability problem, this research was conducted to give alternative product which is hopefully more stable during storage. The product which was developed in this research was instant based product by using spray drying technology and adopted the one of pharmaceutical drugs form, the effervescent. The main reason effervescent based product was chosen because it can deliver the good acceptance of the product to the consumer especially the one which has not pleasant flavor. The extract of mangosteen it self contains a lot of bioactive compound which is usually well-known by its unpleasant taste. In other words, by using effervescent technology, giving the product it self other advantage such easily self-solving and having a good acceptance because of sparkling sensation. Therefore, the product will be able to be consumed conveniently. Based on the research result, the best condition to spray dry the extract of mangosteen pericarp was by inlet spray dryer temperature 160 oC, outlet temperature 82 ± 2 oC, fluid rate 12.14 ml/minute and added by 15 % of maltodextrin dextrose equivalent 15-20. The powder contain 25,01 ± 5,29 mg/g dry encapsulated extract or 1,13 ± 0,02 mg/g dry matter of anthocyanin, 188,40 ± 0.04 mg/g dry encapsulated extract or 8,9 ± 0,00 mg/g dry matter fenolic compound, and 0,59 ± 0,00 mg/g dry matter of -mangostin, one of most abundant xanthones groups compounds. All this properties are giving a donation to anti-oxidant properties by amount 428.72 ± 1,65 mg equivalent to ascorbic acid/g dry matter.The chosen formulation has composition mangosteen extract powder, aspartame, sodium bicarbonate, citric acid, malic acid, PEG and sorbitol.
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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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