Judul: Ketahanan Hidup Pediococcus pentosaceus BP (20) dalam Es Krim Sinbiotik Spirulina Fermentasi Selama Penyimpanan
Abstrak: Bakteri asam laktat genus Pediococcus memiliki suhu optimum pertumbuhan di kisaran 25 ºC ˗ 40 ºC, belum diketahui bagaimana ketahanan hidup bakteri ini jika disimpan dalam suhu beku (-5 ºC) pada produk es krim. Penelitian ini bertujuan menentukan pengaruh penambahan spirulina fermentasi terhadap karakteristik es krim sinbiotik dan ketahanan hidup P. pentosaceus BP (20) dalam es krim sinbiotik spirulina fermentasi perlakuan terbaik selama penyimpanan pada suhu beku beserta potensi aktivitas antioksidannya. Spirulina difermentasi dengan P. pentosaceus BP (20) menghasilkan karakteristik total BAL 8,01 log cfu/mL, nilai pH 4,26, dan kadar TAT 0,20%. Spirulina fermentasi kemudian difortifikasi ke dalam es krim tanpa penambahan (ES0), 10 g (ES10), 15 g (ES15), dan 20 g (ES20). Total mikroba yang diperoleh <4,00-6,18 log cfu/mL, total BAL 0,00-5,72 log cfu/mL, kadar TAT 0,21-0,52%, nilai pH, 6,75-6,71, overrun 30,83-23,67%, daya leleh 0,87-0,94 g/menit, total padatan 45,28-43,37%, kadar protein 15,38-17,07%, dan kadar lemak 10,59-12,35%. Perlakuan terbaik diperoleh pada ES15 yang memiliki karakteristik total mikroba dan total BAL >105 cfu/mL, pH 6,72, kadar TAT 0,48%, overrun 26%, daya leleh 0,9 g/menit, total padatan 42,03%, kadar protein 17,07%, kadar lemak 12,35%, dan aktivitas antioksidan lemah. Ketahanan hidup BAL selama 28 hari penyimpanan menurun sebesar 10,43%., Lactic acid bacteria genus Pediococcus have an optimum growth temperature in the range 25 ºC ˗ 40 ºC, it is not yet known how the survival of this bacteria if stored in freezing temperatures (-5 ºC) in ice cream products. This study aims to determine effect of adding fermented spirulina on the characteristics and the survival of P. pentosaceus BP (20) in synbiotic ice cream with the best treatment during storage at freezing temperatures along with potential antioxidant activity. Spirulina was fermented with P. pentosaceus BP (20) resulting in LAB 8.01 log cfu/mL, pH 4.26, and TAT 0.20%. Fermented spirulina then fortified into ice cream 0 g (ES0), 10 g (ES10), 15 g (ES15), and 20 g (ES20). Total microbes obtained <4.00-6.18 log cfu/mL, LAB 0.00-5.72 log cfu/mL, TAT 0.21-0.52%, pH 6.75-6.71, overrun 30.83-23.67%, melting power 0.87-0.94 g/min, total solids 45.28-43.37%, protein content 15.38-17.07%, and fat content 10.59-12.35%. The best treatment was obtained from ES15 which had characteristics of total microbes and LAB >5 log cfu/mL, pH 6.72, TAT 0.48%, overrun 26%, melting power 0.9 g/min, total solids 42.03%, protein content 17.07%, fat content 12.35%, and weak antioxidant. The survival of LAB for 28 days of storage decreased by 10.43%.
Keyword: Ice cream, Fermentation, Pediococcus pentosaceus BP (20), Survival, storage

Judul: Fermentation of Spirulina plantensis by Lactobacillus plantarum SK(5) and its Fortification on Probiotic Ice Cream
Abstrak: Spirulina dapat berperan sebagai prebiotik bagi bakteri bakteri asam laktat probiotik. Lactobacillus plantarum SK(5) merupakan bakteri asam laktat asal bekasam yang bersifat sebagai probiotik. Penelitian ini bertujuan menentukan karakteristik spirulina fermentasi dan pengaruh perbedaan konsentrasi spirulina fermentasi terhadap karakteristik es krim spirulina probiotik. Spirulina platensis diperoleh melalui kultivasi mandiri selama 13 hari dengan nilai optical density (OD) sebesar 0,54. Biomassa spirulina difermentasi menggunakan Lactobacillus plantarum SK(5) pada suhu 37℃ selama 48 jam. Karakteristik spirulina fermentasi yang dihasilkan yaitu pH 3,38, total asam tertitrasi 0,7% dan total bakteri asam laktat 8,15 log cfu/mL. Spirulina fermentasi selanjutnya difortifikasi ke dalam es krim dengan formula E0 (tanpa penambahan spirulina fermentasi), E10 (10 g), E15 (15 g), dan E20 (20 g). Data yang dianalisis pada es krim probiotik meliputi overrun, total padatan, daya leleh, komposisi kimia (protein, lemak, air, abu, dan karbohidrat), total BAL, kadar TAT dan nilai pH. Es krim spirulina probiotik memiliki overrun 19,25-20,42%, total padatan 40,55-42,37%, daya leleh 1,41- 1,53%, kadar protein 6,23-7,33%, kadar lemak 3,49-3,37%, kadar air 57,63- 59,46%, kadar abu 1,70-1,85%, karbohidrat 28,67-29,72%, nilai pH 6,22-6,27, total asam tertitrasi 0,52-0,68%, dan total bakteri asam laktat 0,00-6,59 log cfu/mL. Es krim yang difortifikasi dengan spirulina fermentasi dapat dinyatakan sebagai produk probiotik. Perlakuan terbaik yaitu formula es krim E20 (fortifikasi spirulina sebanyak 20 g), mempunyai karakteristik total padatan 41,79%, kadar protein 7,33%, total BAL 6,59 log cfu/mL (106 cfu/mL) kadar TAT 0,86% dan nilai pH 6,22., Spirulina can act as a prebiotic for probiotic lactic acid bacteria. Lactobacillus plantarum SK(5) is a lactic acid bacteria from fermented fish product which acts as a probiotic. This study aims to determine the characteristics of fermented spirulina and the effect of different concentrations of fermented spirulina on the characteristics of probiotic spirulina ice cream. Spirulina platensis was obtained through self-cultivation for 13 days with an optical density (OD) value of 0,54. Spirulina biomass was fermented using Lactobacillus plantarum SK(5) at 37℃ for 48 hours. The characteristics of fermented spirulina produced were pH 3,38, total titrated acid 0,7% and total lactic acid bacteria 8,15 log cfu/mL. The fermented spirulina was then fortified into ice cream with the formula E0 (without the addition of fermented spirulina), E10 (10 g), E15 (15 g), and E20 (20 g). Characterization of probiotic ice cream included overrun, total solids, melting power, chemical composition (protein, fat, water, ash, and carbohydrates), total LAB, TAT content and pH values. Characteristics of probiotic spirulina ice cream were overrun of 19,25-20.42%, total solids 40,55-42,37%, melting power 1,41- 1,53%, protein content 6,23-7,33%, fat content 3,49-3,37%, water content 57,63- 59,46%, ash content 1,70-1,85%, carbohydrates 28,67-29,72%, pH value 6,22-6,27, total titrated acid was 0,52-0,68%, and total lactic acid bacteria was 0,00-6,59 log cfu/mL. Ice cream fortified with fermented spirulina can be declared as a probiotic product. The best treatment was ice cream formula E20 (it fortified with fermented spirulina of 20 g), which had the characteristics of total solids 41,79%, protein content 7,33%, total LAB 6.59 log fcu/mL (106 cfu/mL), TAT content 0,86% and pH value 6,22.
Keyword: Spirulina, Es krim, Fermentasi, Lactobacillus plantarum SK(5), Bakteri asam laktat, Ice cream, Probiotik, Probiotic, Lactic acid bacteria, Fermentation, Fermented spirulina, Spirulina fermentasi

Judul: Rantai Markov Pada Bilangan Biner
Abstrak: Ranlai Markov {Xn} yang didefinisikan pada ruang peluang (n, P, P) dilllana n = (O,I],dan 'Fadalah cr-lapangan Borel, lllelllpunyai ekspansi biner X n = 0, dl(n) din).. n = I, 2, ... Mengkonstruksi rantai Markov ini diawali dengan memilih sembarang bilangan ..Y o di (0,1], nyatakan bilangan Xo dalam ekspansi biner Xo =0, diD) diD) ... d~O) ... dimana { d~O) ,n = 1,2, ... } adalah barisan nol dan satu. Peubah acak XI ditentukan oleh .Xo dan asumsi berikut.
Keyword: