Fermentasi Asam Asetat dengan Sel Amobil Acetobacter Pasteurianus INT-7 dengan Variasi Ph Awal dan Kadar Etanol

Tujuan penelitian ini adalah mendapatkan kondisi optimum fermentasi dengan sel amobil dan hasilnya dibandingkan dengan sel bebas. Penelitian ini diawali dengan pembuatan sel amobil dengan jumlah sel awal 107 CFU/mL, larutan alginat 3 %, ratio jumlah sel dan alginat 1:3 (v/v) dan pengkondisian sel amobil pada media pertumbuhan PGY-2 % etanol (pepton glucose yeast extract) pada inkubator goyang 150 rpm, 30 oC selama 1 hari. Sel amobil yang sudah dikondisikan dicuci 2 kali dengan akuades steril dan siap digunakan untuk fermentasi menggunakan media YEPM (yeast extract pepton malt) dengan variasi pH awal (5,5;6,0 dan 6,5), kadar etanol (5,0; 7,5 dan 10 % b/v) dan waktu fermentasi pada inkubator goyang 150 rpm, 30 oC selama 10 hari. Pengukuran produksi asam asetat dan jumlah sel dilakukan pada hari 1, 3, 5, 7, 8, 9 dan 10 hari. Hasil penelitian menunjukkan bahwa kondisi optimum fermentasi dengan sel amobil adalah pH awal media 6,0; kadar etanol 7,5 % suhu 30 oC selama 7 hari. Penggunaan sel amobil dalam fermentasi asam asetat dapat meningkatkan resistensi etanol dan waktu optimum fermentasi dicapai lebih lama. Fermentasi dengan sel amobil Acetobacter pasteurianus INT-7 pada kondisi optimum menghasilkan asam asetat sebesar 35,81 g/L dan 16,29 g/L pada fermentasi dengan sel bebas. Efisiensi fermentasi dengan sel amobil (36,73 %) lebih besar daripada sel bebas (16,17 %)

Peranan HACCP dalam Industri Pangan

keyword: hccp, industri panga

Isolation and Purification of Oxalate Oxidase From Barley Seedling

A procedure of isolation of oxalate oxidase from barley seedling and a new method for purification is described. A purification step was accomplished by the second partition using polyethylene glycol (PEG-6000) and Devi-Iran-500 (4.5%1 4), and affinity chromatography using oxalate immobilized on activated CNBR-Sepharose 6MB as a ligand. After partition some protein were separated, and the specific activity were increased by 5-30 fold. The affinity chromatography using Oxalate-Sepharose effectively separated the oxalate oxidase. The specific activity of pure enzyme was 154.3 U/mg protein and the purity was 41 fold

Some Characteristics of Oil Palm and Sago Starch Acetates

Pati kelapa sawit dan pati sagu diasetilasi dengan anhidrid asetat pada suhu 25°C dalam larutan alkali. Tingkat pemberian anhidrit asetat adalah 2,5 - 15,0 %, berdasar berat kering pati. Pati asetat yang diperoleh dicirikan mengenai tingkat substitusi (DS), perilaku pembentukan pasta, kemampuan penggelembungan, dan kedapat cernaannya menggunakan amilase pankreas babi. Hasilnya menunjukkan bahwa makin banyak tingkat pemberian anhidrid asetat menghasilkan pati dengan DS makin besar. Prosedur modifikasi yang dilakukan menghasilkan turunan pati dengan DS 0,007 - 0,095 untuk pati kelapa sawit, dan DS 0,041 - 0,056 untuk pati sagu. Asetilasi berakibat menurunkan suhu pembentukan pasta, meningkatkan kemampuan penggelembungan, dan menurunkan kedapatcernaannya secara in vitro. Pati kelapa sawit dan turunannya memiliki suhu pembentukan pasta yang lebih rendah dari pada pati sagu dan turunannya. Sifat-sifat pati kelapa sawit mirip dengan sifat-sifat pati sagu dalam beberapa hal

Some Characteristics of Cross-Linked Hidroxypropyl Sago Starch

Sago starch was laboratory hydroxypropylated using 1% propylene oxide in alkaline condition, then cross-linked using 9.000 - 0.025 % phosphorus oxychloride. The dual modified starches with level of cross-linking ranging from 0.0000 to 0.0186 were characterized for amylographic properties, swelling power, paste turbidity, and in vitro digestibility using porcine pancreatic a-amylase. The cross-linking procedure applied to dual modification nearly unchanged the pasting temperature, i. e. at 62.5°C. Cross-linked, hydroxypropyl starches with DS more than 0.0150 had similar amylographic properties which showed high heat and shear stability of the paste. Cross-linking resulted in decrease in the swelling power and the in vitro digestibility of the starch. Hydroxypropylationprior to subsequent modification facilitate the cross-linking with a consequence of lower pasting temperature, higher maximum viscosity, higher swelling power, and lower digestibility

Aspergillus Proteolitik Indigenous dari Koji dan Kemampuannya Mendegradasi Aflatoksin B1

Legume and cereals are always exposed to the danger of fungal contamination. Among such fungi, some species of the genus Aspergillus are potential of aflatoxins producer. Aflatoxin BI (AFB1) which is the most carcinogenic mycotoxins , known very stable under cooking condition and other processing factors. The removal of AFB1 by degradation or detoxification is critical to reduce risk to human health. Microbiological degradation is a promising method for AFB1 degradation compared to others. The aim of this research was to isolate the proteolytic Aspergillus strain from "koji" and to determine its ability to degrade AFB). Out of 18 strains of Aspergillus, 16 strains were found proteolytic and only 5 strains had no afiatoxigenic properties, but all of them were able to degrade AFB1. There were no spesific pattern of the rate of AFBI degradation. Strain of KKB4 was identified as Aspergillus oryzae, that possess the highest ability to degrade AFB1. Two kind of substances were formed after degradation which were more polar than AFB1. The rate of AFB) uptake by Aspergillus oryzae KKB4 was similar with that of mycelia! growth. Aflatoxin BI inhibits mycelium growth, vesicle and conidial head formation