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PREDICTION OF MICROBIAL POPULATION IN SORGHUM FERMENTATION THROUGH MATHEMATICAL MODELS Laila, Umi; Nurhayati, Rifa; Utami, Tyas; Rahayu, Endang Sutriswati
Reaktor Volume 19 No. 4 December 2019
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (16.534 KB) | DOI: 10.14710/reaktor.19.4.152-161

Abstract

The mathematical models can be used as a tool in predicting microbial population in sorghum fermentation, either spontaneous fermentation or fermentation with the addition of lactic acid bacteria (LAB) inoculum. Gompertz model modified by Gibson, Gompertz model modified by Zwietering, Baranyi-Robert model, Fujikawa model, Richards model, Schnute model were used in predicting the growth of lactic acid bacteria (LAB) and coliform bacteria during spontaneous fermentation, and also the growth of LAB during fermentation with the addition of inoculum. Meanwhile, there was death (inactivation) of coliform bacteria during sorghum fermentation with the addition of LAB inoculum. The Geeraerd model and the Gompertz model modified by Gil et al. were used to predict the inactivation. The accuracy and precision of models were evaluated based on the Root Mean of Sum Square Error (RMSE), coefficient of determination (R2), and curve fitting. Gompertz model modified by Gibson had the highest accuracy and precision, which was followed by the accuracy of the Fujikawa model and Baranyi-Robert model in predicting the growth of LAB and the growth of coliform bacteria during spontaneous fermentation. Meanwhile, in predicting LAB growth during fermentation with the addition of inoculum, high accuracy and precision was obtained from Richards and Schnute models. In predicting the inactivation of coliform bacteria, Geeraerd model provided higher accuracy and precision compared to Gompertz model modified by Gil et al. Keywords: fermentation; inoculum; mathematical; model; sorghum; spontaneous
ISOLASI DAN IDENTIFIKASI BAKTERI ASAM LAKTAT PROTEOLITIK DARI SUSU KEDELAI YANG TERFERMENTASI SPONTAN Yusmarini, Yusmarini; Indrati, Retno; Utami, Tyas; Marsono, Yustinus
Jurnal Natur Indonesia Vol 12, No 1 (2009)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (188.878 KB) | DOI: 10.31258/jnat.12.1.28-33

Abstract

Lactic acid bacteria is a group of bacteria with proteolytic activities enambling to grow on protein rich substratesuch as soymilk. This research was aim to isolate and identify lactic acid bacteria with have proteolytic activityfrom spontaneous fermented soy milk. Sixteen isolates out of 26 colonies isolated from fermented soymilk arepresumed as lactic acid bacteria. Among these 16 isolates, only 3 of them showed proteolytic activity. These threeisolates were further identify morphologically and only two isolates identified as Lactic Acid Bacteria, namelyR.1.3.2 and R.11.1.2. The ability of these isolates to produce acid and protease were observed. The results showedthat isolate R 1.2.3 higher ability in producing protease.
PENGIKATAN GARAM EMPEDU OLEH SUSU KEDELAI TERFERMENTASI DAN STABILITASNYA TERHADAP PEPSIN DAN PANKREATIN [BINDING OF BILE SALTS BY FERMENTED SOYMILK AND ITS STABILITY AGAINST PEPSIN AND PANCREATIN] Yusmarini, .; Indrati, Retno; Utami, Tyas; Marsono, Yustinus
Jurnal Teknologi dan Industri Pangan Vol. 24 No. 1 (2013): Jurnal Teknologi dan Industri Pangan
Publisher : Departemen Ilmu dan Teknologi Pangan, IPB Indonesia bekerjasama dengan PATPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (381.471 KB) | DOI: 10.6066/jtip.2013.24.1.105

Abstract

ABSTRACT Processed soybean products especially the fermented ones have beneficial health effects since they are capable of reducing the level of plasmacholesterol (hypocholesterolemic effect). One of the mechanisms is by increasing the binding of bile salt. This research was aimed to assess the ability of soymilk, fermented soymilk products and fermented soymilk products combined with enzymatic hydrolysis to bind bile salts. The stability of the binding against hydrolysis by digestive enzymes (pepsin and pancreatin) was also evaluated. Fermented soybean products inoculated with isolates of L. plantarum 1 R.11.1.2 was be able to bind 1.40 ?mol/100 mg protein (62.26%) of natrium taurocholate. This binding ability is slightly higher than that of soymilk to natrium taurocholate, i.e.1.33 ?mol/100 mg protein (59.04%). Addition of a protease enzyme specific to hydrophobic amino acid (thermolysin) on fermented soymilk products was able to enhance the ability of bind natrium taurocholate. Enzymatic hydrolysis products having a molecular weight of
PENURUNAN KADAR AFLATOKSIN B1 PADA SARI KEDELAI OLEH SEL HIDUP DAN SEL MATI LACTOBACILLUS ACIDOPHILUS SNP-2 [REDUCTION OF AFLATOXIN B1 IN SOYMILK BY VIABLE AND HEAT-KILLED LACTOBACILLUS ACIDOPHILUS SNP-2] Utami, Tyas; Nugroho, FX. Hartanta Adi; Usmiati, Sri; Marwati, Sri; Rahayu, Endang S.
Jurnal Teknologi dan Industri Pangan Vol. 23 No. 1 (2012): Jurnal Teknologi dan Industri Pangan
Publisher : Departemen Ilmu dan Teknologi Pangan, IPB Indonesia bekerjasama dengan PATPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (271.008 KB)

Abstract

Aflatoxins are carcinogenic mycotoxins that commonly contaminate foods and feed. There are many different forms of aflatoxin and its metabolites. Of these, aflatoxin B1 (AFB1) is the most prevalent and toxic. Lactobacillus acidophilus SNP-2 has previously been shown to remove AFB1 from liquid solution of phosphate saline buffer. However, the ability of lactic acid bacteria to reduce AFB1 content in soymilk has not been studied yet. The objective of this study was to investigate the ability of viable and heat-killed cells of L. acidophilus SNP-2 to reduce AFB1 in soymilk and fermented soymilk. Soymilk contaminated with Aspergillus flavus was inoculated with culture of L. acidophilus SNP-2, and incubated at 37°C for 12 hours. Fermented soymilk, then, was heat sterilized and stored at cool room (4°C). Heat-killed cells were introduced to soy milk and then kept at cool room for 3 days. During soymilk fermentation, there was reduction of AFB1 content in soymilk related to the growth of lactic acid bacteria and the reduction of pH. The initial concentration of AFB1 in the soymilk was 4.9 ppb. Lactobacillus acidophilus SNP-2 reduced 67.58% of AFB1 in the soymilk after 12 hoursof fermentation. In cool environment, the binding of AFB1 to heat-killed cell after soymilk fermentation was relatively more stable than that of soymilk without fermentation. 
KETAHANAN DAN VIABILITAS PROBIOTIK BAKTERI ASAM LAKTAT SELAMA PROSES PEMBUATAN KULTUR KERING DENGAN METODE FREEZE DAN SPRAY DRYING [SURVIVAL AND VIABILITY OF LACTID ACID BACTERIA PROBIOTIC DURING PRODUCTION OF DRIED CULTURE USING FREEZE AND SPRAY DRYING Harmayani, Erni; Ngatirah, .; Rahayu, Endang S.; Utami, Tyas
Jurnal Teknologi dan Industri Pangan Vol. 12 No. 2 (2001): Jurnal Teknologi dan Industri Pangan
Publisher : Departemen Ilmu dan Teknologi Pangan, IPB Indonesia bekerjasama dengan PATPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (708.08 KB)

Abstract

Selection on 36 lactid aid bacteria isolate from various source (dadih, sausage, infant faces, gato, chinese leaf pickle, growol and yoghurt) has been carried out based on their potency to reduce choresterol. Based on their ability to assimilate choresterol, conjugate bile solt, restency on bile salt and low pH, three isolates i.e. Lactobacillus sp. Dad 13, L. asidophillus D2 and L. plantarum Mut 7 have been chosen for further study. Viability of selected cultures during biomass production using coconut water with addition of 0.5% yeast extract, and during production of dried starter culture using freeze and spray dried were investigated. The results show that the growth patern of  the three isolates selected were almost similar i.e. reaching maximum amount after 16 hours fermentation at 37°C. biomass production using coconut water produced 109 cfu/ml after 16-18 hours incubation at 37°C. decrease on viability after drying using freeze drier ranged between 0.5-2 log cycles, while that of storage of freeze dried culture during 4 weeks at -20°C caused descreasing in viability of 26-56%.
SINTESIS ESTER METIL RANTAI MEDIUM DARI MINYAK KELAPA DENGAN CARA METANOLISIS KIMIAWI (Chemical Methanolysis in Synthesis of High Medium Chain Fatty Acids Methyl Ester from Coconut Oil) Karouw, Steivie; ., Suparmo; Hastuti, Pudji; Utami, Tyas
Jurnal Agritech Vol 33, No 02 (2013)
Publisher : Jurnal Agritech

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Abstract

Synthesis of fatty acid methyl ester from coconut oil has conducted by chemical methanolysis. The objectives of the research were to evaluate the effect of temperature reaction on yield and profile of fatty acid methyl ester and the fractionation process on medium chain fatty acids methyl ester content. Coconut oil was extracted from 11-12 months of Mapanget Tall coconut variety fruit. The oil was then analyzed to evaluate the physycochemical properties and fatty acids profile. Methanolysis reaction was conducted using potassium metoxide as a catalyst at 50, 55 and 60oC for 2 hours. The methanolysis products were then measured for the yield and were determined for fatty acids profile. Furthermore, the fatty acid methyl ester was franctionated by melting from solid to liquid form. The results showed that the coconut oil had a good quality and medium chain fatty acid content was 61.93%, whereas lauric acid was the major component about 48.24%. The yield of fatty acid methyl ester was 85.41-86.69% and medium chain methyl ester content were 60.81%, 61.84% and 59.85% at reaction temperature of 50oC, 55oC and 60oC, respectively. Ester methyl lauric was a major component of 48.84 – 49.04%. Dry fractionation process only increased 6.68% of fatty acids methyl laurate content. Keywords: Synthesis, medium chain methyl ester, coconut oil, methanolysis ABSTRAK Pada penelitian ini dilakukan sintesis ester metil asam lemak minyak kelapa dengan cara metanolisis kimiawi. Tujuan dari penelitian ini adalah mengetahui pengaruh suhu metanolisis terhadap yield dan profil ester metil asam lemaknya serta perlakuan fraksinasi terhadap kandungan ester metil asam lemak rantai medium. Minyak kelapa diekstraksi dari daging buah kelapa varietas Dalam Mapanget umur buah 11-12 bulan. Minyak kelapa yang diperoleh dianalisis sifat kimianya dan profil asam lemaknya. Reaksi metanolisis dilakukan secara kimiawi menggunakan katalisator kalium metoksida pada suhu 50, 55 dan 60oC selama 2 jam. Hasil metanolisis diukur yield dan proporsi asam lemaknya. Selanjutnya ester metil yang dihasilkan difraksinasi dengan metode beku ke cair. Hasil analisis diperoleh bahwa minyak kelapa mempunyai kualitas yang baik dan asam lemak rantai medium sebesar 61,93% yang didominasi oleh asam laurat sekitar 48,24%. Yield ester metil yang dihasilkan berkisar 85,41-86,69% dengan total kandungan ester metil rantai medium yang dihasilkan berturut-turut 60,81%, 61,84% dan 59,85% masing-masing pada suhu 50oC, 55oC dan 60oC. Proporsi tertinggi adalah ester metil laurat yaitu sebesar 48,84 - 49,04%. Proses fraksinasi kering dengan metode beku ke cair hanya dapat meningkatkan proporsi ester metil laurat sebesar 6,68%. Kata kunci: Minyak kelapa, metanolisis, ester metil rantai medium, fraksinasi
Pengaruh Infeksi Escherichia coli dan Pemberian Lactobacillus plantarum Dad 13 terhadap Mikrobiota Feses Tikus Wistar Sumaryati, Bekti Tri; Utami, Tyas; Suparmo, Suparmo
Agritech Vol 29, No 4 (2009)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (416.491 KB) | DOI: 10.22146/agritech.9692

Abstract

The antibacterial activity of Lactobacillus plantarum Dad 13 to pathogenic Escherichia coli was studied in vitro using well diffusion method. The effects of E. coli infection and addition of L. plantarum Dad 13 on fecal microbiota of Wistar rats were studied in-vivo. Rats were fed with standard feed. After five days they were divided into two groups. Rats in the first group were infected with 1010  CFU E. coli enterotoxigenic stabile toxin and rats in the second group were fed with 109  CFU L. plantarum Dad 13 for a week. Samples were taken before and after treatment for enumeration of E. coli, coliform, and lactobacilli in the feses. The results showed that L. plantarum Dad 13 could inhibit pathogenic E. coli indicated by clear zones. Escherichi coli infection didn’t significantly increased the count of E. coli and coliform in the feses, but reduced 0.4 log cycle of the total lactobacilli. Lactobacillus plantarum Dad 13 increased 1.2 log cycle of the total lactobacilli, but did not reduced the count of E. coli and coliform. Infection of E. coli and addition of L. plantarum Dad 13 changed the ratio among fecal microbiota of rats.ABSTRAKTujuan dari penelitian ini adalah mempelajari aktivitas antibakteri Lactobacillus plantarum. Dad 13 terhadap Escher­ ichia coli patogen penyebab diare secara in vitro, dan pengaruh infeksi E. coli patogenik dan pemberian L. plantarum Dad 13 terhadap mikrobiota feses tikus Wistar. Tikus percobaan diberi pakan standar selama lima hari, kemudian dibagi menjadi dua kelompok. Kelompok pertama, tikus diinfeksi dengan 1010 CFU E. coli patogen, sedang tikus pada kelompok kedua diberi L. plantarum Dad 13 sebanyak 109  cfu selama satu minggu. Sebelum dan setelah perlakuan, dilakukan enumerasi E. coli, coliform, dan lactobacilli pada feses tikus. Hasil yang diperoleh menunjukkan bahwa secara in vitro Lactobacillus sp. Dad 13 dapat menghambat pertumbuhan E. coli patogenik. Infeksi dengan 1010 CFU E. coli enterotoksigenik stabil toksin pada tikus Wistar tidak meningkatkan jumlah E. coli dan coliform, namun menu­ runkan jumlah lactobacilli sebesar 0,4 siklus log. Pemberian L.plantaraum Dad 13 tidak dapat menurunkan jumlah E. coli dan coliform, namun dapat meningkatkan jumlah lactobacilli sebesar 1,2 siklus log. Infeksi E. coli dan pemberian L. plantarum Dad 13 mengubah rasio mikrobia dalam feses.
Perubahan Sifat-Sifat Biokimiawi, Fisikawi, Mikrobiawi, dan Sensoris Produk "Wadi" Ikan Betok (Anabas testudineus Bloch) Khairina, Rita; Utami, Tyas; Harmayani, Eni
Agritech Vol 19, No 4 (1999)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2140.849 KB) | DOI: 10.22146/agritech.13719

Abstract

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Pediococcus acidilactici F-11 Penghasil Bakteriosin sebagai Agensia Biokontrol Escherichia coli dan Staphylococcus aureus pada Sayuran Segar Simpan Dingin Rahayu, Endang Sri; Harmayani, Eni; Utami, Tyas; Handarini, Kejora
Agritech Vol 24, No 3 (2004)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2344.649 KB) | DOI: 10.22146/agritech.13456

Abstract

Our survey indicated that fresh vegetables contained. high population of microorganisms including pathogenic Staphylococcus aureus. Washing procedures, including the addition of sanitizes to the wash water have not been effectively in reduction of the number of microorganisms. Currently, there is interest in possible use bacteriocin producer of lactic acid bacteria as biocontrol agents to ensure safety of minimally processed, refrigerated (MPR) foods which are not acidified, including fruits and vegetables. Our previous result, indicated that Pediococcus acidilactici F-11 (PAF-11) produced bacteriocin with wide spectrum activity. Objectives of this research was to study the potency of PAF-I 1 as biocontrol agent to inhibit the growth of pathogenic bacteria occurred in ready to eat fresh vegetables, i.e., paprika, lettuce, carrot. The results showed that PAF-11 was able to inhibit the growth of naturally present coliform and Staphylococcus significantly, as well as that of tested bacteria of E. coil and S. aureus which were inoculated into paprika and carrot. PAF-11 was able to grow at these two vegetables, and their population were increased about I log cycle. Bacteriocin activity produced by PAF-11 was positively detected from these two vegetables inoculated with these bacteria. However, there was no inhibition activity of PAF-11 against naturally present coliform and Staphylococcus, as well as inoculated E. coil and S. aureus on lettuce. Bacteriocin activity produce by PAF-11 was also not detected in this vegetables. Conclusion of this study, Pediococcus acidilactici F-11 could be used as biocontrol agents in paprica and carrot.
The Effect of Addition of Lactobacillus plantarum S4512 on The Microbiological and Chemical Characteristics during Sorghum (Sorghum bicolor L. Moench) Fermentation Utami, Tyas; Nurhayati, Rifa; Rahayu, Endang Sutriswati
Agritech Vol 35, No 4 (2015)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (385.835 KB) | DOI: 10.22146/agritech.9329

Abstract

The aim of this study was to investigate the population of selected bacteria and some chemical characteristics during sorghum fermentation with the addition of Lactobacillus plantarum S4512. Proteolytic L. plantarum S4512 isolated from natural sorghum fermentation was added into sorghum fermentation. Sorghum flour was mixed with sterile water (1:2 w/v) and then was inoculated with 1% v/v (about 109 CFU/ml) culture of L. plantarum S4512. Fermentation was carried out at 37°C for 24 hours. As a control, natural sorghum fermentation without addition of a starter culture was carried out at 30°C for 24 hours. During fermentation time, the amount of bacteria, acid producing bacteria, coliform and proteolytic bacteria were monitored. The titratable acidity, pH, soluble protein, and proteolytic activity were also measured. Addition of L. plantarum S4512 increased significantly the initial population of total bacteria, lactic acid bacteria and proteolytic bacteria to 107 CFU/ml and suppressed the growth of coliforms indicated by siginificantly decline of coliforms population after 6 h fermentation. The production of acid was doubled of that in the natural fermentation resulted in the lower pH to 3.14. Both natural sorghum fermentation and that with addition of proteolytic L. plantarum S4512 showed some proteolytic activities during fermentation.