{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