{abstract} DAMPAK KONDISI EKSTRIM SUHU DAN KELEMBABAN TERHADAP PERTUMBUHAN Aspergillus flavus DAN PEMBENTUKAN AFLATOKSIN PADA KEDELAI (Impact of Extreme Condition (Temperature and Relative Humidity)for Aspergillus flavus Growth and Aflatoxin Production on Soybean)

By: Rahayu WP1),2), Broto W3), Ambarwati S4), Dian Herawati1),2), Lioe HN1), Pratiwi C5). 1)Department of Food Science and Technology-IPB, 2)SEAFAST Center-IPB, 3)Agency for Research and Development of Agricultural Postharvest, Ministry of Agriculture. 4)SEAMEO BIOTROP, 5) Food Science Post Graduate Student.

 http://www.clt.astate.edu/mhuss/Aspergillus flavus pict.jpg

http://www.clt.astate.edu/mhuss/Aspergillus flavus pict.jpg

Aspergillus flavus producing aflatoxin is found contaminating crops such as soybean. The growth of this mold on soybean and other food is affected by temperature and relative humidity (RH). The aim of this study was to measure the growth and aflatoxin production of A.flavus at different temperature and relative humidity. A. flavus Bio 2237 was inoculated on  medium namely Czapek Dox Agar (CDA), and soybean,  and incubated for 10 days at 20, 30, 40oC and RH 70, 80, 90%, respectively. Aflatoxin analysis was conducted using RP-HPLC equipped by fluorescent detector and post column photochemical reactor. These instruments had LoD 0.45, 0.26, 0.05, and 0.13 ppb, while the LoQ were 1.50, 0.88, 0.18, and 0.43 ppb,  for aflatoxin B1, B2, G1, and G2 respectively. Optimum growth for  A. flavus Bio 2237 on CDA medium and soybean were reached at 30oC with RH 90%. Maximum aflatoxin (999 ppb) production on soybean was reached at those conditions as well. A. flavus could not grow as well as produce aflatoxin at extreme condition (40ºC and RH70%) on soybean.

 

Keywords: aflatoxin, Aspergillus flavus, extreme condition, soybean.

 Dipresentasikan pada Seminar Hasil Hasil Penelitian IPB, 23-24 Desember 2013.

 

{abstract} MODIFIKASI PATI GARUT (Marantha arundinacea L) DENGAN PERLAKUAN HIDROLISIS ASAM DAN SIKLUS PEMANASAN-PENDINGINAN UNTUK MENGHASILKAN PATI RESISTEN TIPE 3 (Modification of Arrowroot (Marantha arundinacea L.) Starch Through Acid Hydrolysis and Autoclaving-Cooling Cycling Treatment to Produce Resistant Starch Type 3)

patiBy: Faridah DN, Rahayu WP, Apriyadi MS (Department of Food Science and Technology. Bogor Agricultural University).

Arrowroot starch can be modified to produce resistant starch (RS), which have been observed to show physiological functions similar to dietary fiber. Acid hydrolysis and autoclaving-cooling cycling treatments can increase RS content. Arrowroot starch modification hydrolyzed by 1.1 and 2.2 N HCl for 0, 2, 4, and 6 hours, then continued with3 cycles of autoclaving-cooling treatment. Based on the starch digestibility, the acid hydrolyzed starch by 2.2 N HCl for 2 hours and 3 cycles of autoclaving-cooling cycling treatment had the lowest digestibility (22.04%). This treatment also increased amylose, dietary fibre, and RS contents. The increase of the amylose contents contributed to increase the total dietary fibre and RS contents up to 4.1 and 4.4 times, respectively, than native starch.

Key words: acid hydrolisis, arrowroot, autoclaving-cooling, resistant starch.

Dimuat di:   J. Tek. Ind. Pertanian 23(1): 61-69. 2013

[abstract] PREVENTION AND REDUCTION OF MYCOTOXIN BY ANTAGONISTIC MICROORGANISM

 http://www.clt.astate.edu/mhuss/Aspergillus flavus pict.jpg

http://www.clt.astate.
edu/mhuss/Aspergillus flavus pict.jpg

By: Winiati P. Rahayu (Department of Food Science and Technology, Bogor Agricultural University).

Mycotoxin is widely known as one cause of the foodborne disease, produced by toxigenic fungi. Its prevalence becomes higher with the availability of supporting conditions such as proper climatic changes, plentiful substrates, and minimum controls. Any country should be aware about this high risk potency in order to maintain food safety and food security by knowing the mycotoxin, the affected commodities, the fungal sources, and  the toxicity effect to human or animal. Indonesia has made some regulations regarding the contamination of mycotoxin to food or feedstuff, including Aflatoxin, Fumonisin, Deoxynivalenol (DON), Ochratoxin, and Patulin (PAT). Besides controlling through regulations, many studies  controlling mycotoxin have also been done throughout the world.   The using of microorganism or metabolite compounds produced by microorganism as biological agent has many advantages such as mild reaction conditions, target specificity, efficiency and environmental friendly. Some microbial strains has been developed as commercial biological agent product including Aspergillus flavus AF36, A. flavus strain NRRL21882, etc. The microbial characteristic used for biological agent should be evaluated including the inability to produce toxic substance, the tendency to multiply, colonize, survive, the safety, and applicability to the environment. Studies related to mycotoxin biocontrol by using microorganism can be focused on (1) the effect to the mycotoxin, (2) the growth of microorganism, or (3) the application to food both raw material and processed products. Consideration to combine more than one species of microorganism instead of a single species also has been taken to gather the possibility of achieving more effective.  For example, Yeast (S. cerevisiae) has been used together with bacteria (LAB) to take control on mycotoxin produced by some fungi. Further studies are still needed to develop the possibility of other biological control agents and the effect of their application, which in the next have the potency to be developed as manufacturing products.

Keywords: alternatives, advantages, biological agents, mycotoxin biocontrol

Presented at International Conference on Mycological Aspects of Food and Feed Safety, Yogyakarta, 27-28 June 2013

 

[abstract] EFFECT of KEBAR GRASS (Biophytum petersianum) LEAF EXTRACT on THE GROWTH AND STRUCTURE of AFLATOXIGENIC Aspergillus flavus

kebar

Source: Private collection

By: Meike M Lisangan1,2, Rizal Syarief1, Winiati P Rahayu1, Okky S Dharmaputra3,4(1 Faculty of Agricultural Engineering and Technology, Bogor Agricultural University, 2  Faculty of Agricultural and Agricultural Technology, The State University of Papua, 3  Faculty of Mathematics and Natural Sciences, Bogor Agricultural University4Southeast Asian Regional Centre for Tropical Biology (SEAMEO BIOTROP)- Indonesia)

The objective of this study was to investigate the chemical composition and antifungal activity of kebar grass polar extract and its effect on the mycelial growth, conidiation and  morphological structure of two isolates of aflatoxigenic Aspergillus flavus, i.e. isolates BCCF0219 and AF1. A total of 64 components were identified using pyrolysis/gas chromatography/mass spectrometry (Py/GC/MS), consisting of a class of carboxylic acids (7.81%), amina (1.56%), phenolics (26.56%), terpenes (15.60%), alcohols (10.94%), hydrocarbons compounds (20.3 %), benzene derivatives (6.25%), carbohydrate derivatives (4.69%), steroidal saponin (1.56%),  haloalkane (1.56%), and sterols (3.13%).In the bioassay, the two isolates of A. flavus were cultured on three  types of model media, i.e. fat-enriched medium, protein-enriched medium and carbohydrate-enriched medium containing five concentrations (12, 14, 16, 18, and 20 mg/mL) of kebar grass polar extract.  The changes of hyphae structure and conidiation were observed usingScanning Electron Microscopy (SEM). The results showed that the percentage of growth inhibition of A. flavus isolate BCCF0219 caused by kebar grass polar extracts at a concentration of 14 mg/mL was 95.5% (in fat-enriched medium), whereas at a concentration of 12 mg / mL was 95.7% (in carbohydrate-enriched medium) and a concentration of 14 mg/mL was 91.0% (in protein-enriched medium).  The percentage of growth inhibition of A. flavusisolate AF1 caused by the extract at  a concentration of 16 mg/mL was 100% (in fat-enriched medium),while at a concentration of 12 mg / mL was 91.4% (in carbohydrate-enriched medium) and at a concentration of 16 mg/mL was 94.3% (in protein-enriched medium). A marked retardation in conidial production of the fungus was noticed in relation to the inhibition of mycelial growth. Under scanning electron microscopy, deformation of hyphae tips, formation of short branches, thinner hyphae, folded hyphae and collapse of entire hyphae were the major changes observed.  Morphological alterations might be due to the effect on cell permeability through the direct interaction between kebar grass extract and the fungal plasma membrane. These findings indicate the potential of  kebar grass leaf extract in preventing aflatoxigenic A. flavus infection  and minimize aflatoxin contaminationin stored food and feedstuff.

 

Keywords: Aspergillus flavus, Biophytum petersianum, growth inhibitor, morphological structure, Scanning Electron Microscopy

Presented at International Symposium on Tropical Fungi, Mikoina. Bogor 10-11 September 2013

 

 

[abstract] THE POTENTIAL IMMUNOMODULATORY EFFECT OF PROBIOTIC L. rhamnosus TW2 AND L. plantarum TW14 ISOLATED FROM LOCAL GOAT MILK AND THEIR INCORPORATION IN CHEESE

OLYMPUS DIGITAL CAMERA

Source: private collection

By:  Nurheni Sri Palupi 1),  Triana Setyawardani 2) and Winiati P Rahayu 1)

1)Department of Food Science and Technology  and SEAFAST Center- Bogor Agricultural University, 2)Faculty of Animal Science, Jenderal Soedirman University

Probiotic is live non-pathogenic microorganisms that give beneficial effects on health when they are administered in adequate amounts.  The objective of the study was to evaluate the influence L. rhamnosus TW2 and L. plantarum TW14 as well as cheese containing the probiotics on the profiles of microflora, morphological profile of ileum and caecum, lymphocyte proliferation and IgA levels in mice. Male SD rats was fed with the probiotics or cheese containing the probiotics for 10 days, infected with S. Typhimurium for 3 days, and continued to be fed with or without the probiotics or the cheese. Additionally a group of mice with standard feeding was used as control group. The results showed that the number of total lactic acid bacteria in the ileum and caecum in probiotic fed mice was higher than control, whereas the number of S. Typhimurium was lower. The growth of S. Typhimurium was completely inhibited when the mice were continuously given probiotics post-infection. Treatment of probiotic isolate was able to improve the number of lymphosite cellsduring the first 10 days, during infection with S. Typhimurium, and postinfection. Treatment of probiotic isolate was able to improve sIgA at the time of S. Typhimurium intervention. In conclusion, mixed isolates of L. rhamnosus TW2 and L. plantarum TW14 and cheese containg the probiotics were able to show preventive and remedial functions during S. Typhimurium ATCC 14028 infection, thus demonstrate the potential immunomodulatory.

Key words: Immunomodulatory, IgA, L. rhamnosus TW2, L. plantarum TW14, probiotic

Presented at 13th Asean Food Conference, SIFST (Singapore Institute of Food Science & Technology), Singapore 9-11 September 2013

 

 

[abstract] ANTIDIARRHEAL AND ANTIOXIDATIVE CAPABILITY OF SYNBIOTIC YOGURT TO THE RATS

synbiotic

Source: Private collection

By: Winiati P. Rahayu, Made Astawan, Tutik Wresdiyati*, and Sandra Mariska

Department of Food Science and Technology, Faculty of Agricultural Technology and Engineering, Bogor Agricultural University,
(*) Department of Anatomy, Physiology, and Pharmacology, Faculty of Veterinary Medicine, Bogor Agricultural University

The objective of this research was to utilize the local probiotic lactic acid bacteria, isolated from beef in some traditional markets in Bogor (L. plantarum 2C12 and L. fermentum 2B4), in synbiotic yogurt making and analyzing its antidiarrheal and antioxidative capability in rat models. The  rats  were  treated  with  synbiotic  yogurt  and  enteropathogenic Escherichia  coli (EPEC) intervention. The antidiarrheal parameters were the appearance and the gravimetrically water content of the rats’ feces. The normal feces was round or oval, black, and hard or soft with lower fecal water content. The diarrheal feces was not round nor oval, liquid or unformed, brownish, and soft or slimy with higher fecal water content. The antioxidative parameter was immunohistochemically  superoxide dismutase  (SOD)  content  in  liver  and  kidney  tissues, shown by brown color in nucleus. This synbiotic yogurt showed antibacterial and antidiarrheal activities in the rat’s model. This research shown that the feces of the rats, which were infected by EPEC and treated by synbiotic yogurt contained L. fermentum 2B4 was normal, specifically oval, black, and soft feces. Whereas, the rats which were infected by EPEC, but were not treated by the synbiotic yogurt shown the diarrheal feces. The synbiotic yogurt also had antioxidative effect. For 21 days treatment with synbiotic yogurt to the EPEC intervention rats, the Cu, ZnSOD content in the liver and kidney increased, 17.72 and 24.96% respectively higher than the rats that were not treated with it.

Published in International Food Research Journal (IFRJ) University Putra Malaysia. Available online at: http://www.ifrj.upm.edu.my

International Food Research Journal 20(2): 703-709 (2013)

[abstract] PRODUCTION AND CHARACTERISTICS OF CANNED TEMPE EXTRACT

OLYMPUS DIGITAL CAMERA

Source: private collection

By: Reggie Surya and Winiati P. Rahayu

(Department of Food Science and Technology, Bogor Agricultural University)

Tempe is a traditional Indonesian food product derived from fermented soybeans using Rhizopus oligosporus. Tempe has many advantages, such as good nutritional value and organic compounds contributing to human health. Tempe’s key benefitsare related to its excellent protein content,
high levels of essential fatty acids, numerous vitamins and minerals, dietary fibres and isoflavones. Tempe extract (tempe milk) is an example of a diversified tempe-based food. The purpose of this study is to produce canned tempe-extract. This study determined the sterilization time, nutrition facts, isoflavone contents, antioxidant capacity and production feasibility of canned tempe-extract. The results showed that the most favourable formula was tempe extract with 7%(w/v) honey as sweetener. The time needed to sterilize the canned tempe-extract (can size 202×308) was 25 minutes after the activation of the retort to reach sterilization level equivalent to Fo value of 2.62 minutes. The sterilization process did not affect the sensory characteristics of canned tempe-extract significantly. The proximate analysis results showed that canned tempe extract contained 90.27% water, 0.06% ash, 3.66%protein, 0.98% fat and 5.03% carbohydrate. The isoflavones analysis results showed that canned tempe-extract contained total isoflavones of 5.09 mg/100g. The canned tempe-extract had antioxidant capacity of 7.13 mgAEq/150ml, which
means 150 ml canned tempe-extract had equivalent antioxidant capacity to 7.13 mg ascorbic acid. The economic study showed the production of canned tempe-extract was feasible.

Published in Asian Journal of Food and Agro-Industry. ISSN 1906-3040. Available online at www.ajofai.info

As. J. Food Ag-Ind. 2012, 5(04), 299-306

[abstract] EFFECTIVENESS OF WAYANG GOLEK ‘BANG TAGOR’ AS A FOOD EDUCATION MEDIA FOR ELEMENTARY SCHOOL CHILDREN

bang tagor

Source: Nissa collection

By: Mochamad Sobich Maimun and Winiati P. Rahayu

(Department of Food Science and Technology, Bogor Agricultural University)

Elementary students are the most susceptible ages to foodborne diseases, due to most of them do not get adequate information about food safety. In 2009, National Agency for Drug and Food Control (NA-DFC) confirmed that 26.09% of food poisoning outbreaks happened at school; and 19.13% were caused by street foods. This research aimed to find out the effectiveness in dissemination of food safety information by using dazzling educative media which was modified wayang golek, called “Bang Tagor”, to 4th and 5th graders of elementary school. The education was conducted by using  story telling on wayang golek “Bang Tagor” stage, food safety posters, booklets, and interactive games which were related to food safety and health. Research has been done from February to June 2012 at two targeted schools by observing and spreading questionnaires to 75 respondents. Program effectiveness was measured based on cognitive, affective, and psychomotor aspects. As the result, the perception of students on food safety and health sharply increased to 15,32% and there were several positive attitude changes after the program.

Published in The 19th Tri-University  International Joint Seminar & Symposium 2012 (Oct.  21- 26, 2012 Bogor Agricultural  University, Indonesia)

[abstrak] STABILISASI BAKTERI ASAM LAKTAT PADA PEMBUATAN KEJU PROBIOTIK SUSU KAMBING (Stabilization of Lactic Acid Bacteria (BAL) on Probiotic Cheese from Goat Milk)

source: http://www.gutflora.org

By: Rahayu W P1), Triana Setyawardani2), Miskiyah3) (1)Department of Food Science and Technology, Bogor Agricultural University, 2)Faculty of Animal Science, Jenderal Soedirman University, 3) Post harvest Research and Development Center, Ministry of Agriculture)

Goat milk is very potential to be future processed because it has low content of lactose, high MCFA, and high nucleotides. Goat milk is a natural source of lactic acid bacteria (LAB) that have beneficial effect to the health. The research successfully isolated Lactobacillus rhamnosus, and L. plantarum 1  and then apply those bacteria on cheese as a form of food diversification. This research were done in three stages, i.e. (1) maintenance and preparation of lactic acid bacteria culture, (2) probiotic cheese making and testing its stability, (3) proximate and sensory test of probiotic cheese. Probiotic cheese using Lactobacillus rhamnosus, and L. plantarum 1  has the stability of LAB for 4 weeks of storage with the number of LAB was 109  log CFU/g. The flavour of resulting cheese was similar to commercial goat cheese, but the texture and taste were different (P<0.05) to commercial goat cheese.  The texture of probiotic soft cheese has a hardness range from 0.115 to 0.452 N. The hardness texture was significantly different at level 5% (P<0.05) for soft cheese compare to the use of different probiotic LAB. The chemical composition of probiotic cheese has moisture content from 56.38 to 60.58%; protein content from 13.57 to 17.40%, fat  17.66 to 20.42% fat and  ash content from 2.69 to 3.19%.

Keywords : goat milk, probiotics, cheese

Dimuat di Jurnal  Penelitian Pascapanen Pertanian, Volume 7 No. 2, 2010, ISSN 0216-1192

[abstract] STABILITY OF VIABLE COUNTS OF LACTIC ACID BACTERIA DURING STORAGE OF GOAT MILK SOFT CHEESE

source: http://www.cheesemaking.com

By: Winiati P. Rahayu, Feri Kusnandar, and Widya Eka Prayitno (Department of Food Science and Technology, Faculty of Agricultural Engineering and Technology, Institut Pertanian Bogor)

The use of goat milk is limited in Indonesia due to lack of good milking practices resulted in disliked goaty smell. One of the method to eliminate this off flavor is by processing the goat milk into soft cheese. The aim of this research was to study the stability of viable starter lactic acid bacteria cultures ( FNCC-0051 and FNCC-0090) during storage of goat milk soft cheese. Three batches of goat milk soft cheeses were produced with different starter cultures FNCC-0051 (5.0 x 106 cfu mL-1 ); FNCC-0090 (5.0 x 106 cfu mL-1 ); and the mixture of FNCC-0051 (2.5 x 106 cfu mL-1 ) and FNCC-0090 (2.5 x 106 cfu mL-1 ). The goat milk cheeses had white color and soft. The viable lactic acid bacteria in the goat milk soft cheese reached 109 cfu g-1 , which was stable for 8 weeks at 5 °C. Panelists liked goat milk soft cheeses, especially in term of its aroma. The specific aroma produced could mask the disliked goaty smell.

Key words: goat milk, soft cheese, starter lactic acid bacteria.

Journal Microbiology Indonesia. ISSN 1978-3477, eISSN 2087-8575. Vol 5, No 4, December 2011, p 149-153. Available online at: http://www.permi.or.id/journal/index.php/mionline

DOI: 10.5454/mi.5.4.1