Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans

The potency of C0₂ gas as an alternative fumigant in controlling stored-product insects, its inhibitory characteristics on the growth of molds and mycotoxins production and quality changes of the treated cocoa beans have been evaluated in four consecutive research experiments. These experiments w...

Full description

Saved in:

Bibliographic Details
Main Author:	Wahyudi, Teguh
Format:	Thesis
Language:	English English
Published:	2003
Subjects:	Plants - Effect of carbon dioxide on Carbon dioxide - Physiological effect
Online Access:	http://psasir.upm.edu.my/id/eprint/8499/1/FSMB_2003_3_A%20D.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-upm-ir.8499
record_format	uketd_dc
spelling	my-upm-ir.84992022-01-25T07:31:33Z Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans 2003 Wahyudi, Teguh The potency of C0₂ gas as an alternative fumigant in controlling stored-product insects, its inhibitory characteristics on the growth of molds and mycotoxins production and quality changes of the treated cocoa beans have been evaluated in four consecutive research experiments. These experiments were focused on the use of high CO₂ concentration during fumigation and followed by prolonged storage practices in laboratory hermetic room, under plastic enclosures or high-pressure chamber. As comparison, treatments using methyl bromide, phosphine and normal air atmosphere were also carried out. Carbon dioxide concentration of 40, 60 and 80% were effective in controlling Ephestia cautella and Araecerus Jasciculatus during 1 to 3 months of exposure, whereas the test insects in the control showed 20-27 survivors for E. cautella and 20 surVIvors for A. Jasciculatus from the initial number of 30 and 20 insects, respectively. This study also found no significant effect of high CO₂ concentration treatments on cocoa beans quality during the exposure time. The growth of A. flavus and aflatoxins production (except for aflatoxin B2) was significantly inhibited in the presence of high concentration of CO₂ atmosphere during I-month storage. Free fatty acids production in the treated cocoa beans was not inhibited by the treatments. Methyl bromide concentration of 15 g/t or 0.66 g/t of phosphine were required to control E. cautella, A. Jasciculatus and Tribolium castaneum. Levels of methyl bromide residues increased from 0.27 ppm to 1.27, 1.49 and 3.10 ppm with an increase in concentration of methyl bromide from 3 g/t to 5,10 and 15 g/t, respectively. Phosphine residues increased from 0.07 ppm to 0.12, 0.11, 0.14 and 0.15 ppm with an increase in concentration of phosphine from 0.33 g/t to 0.66, 1, 2 and 3 g/t respectively. Methyl bromide fumigation resulted in methylation of proteins as indicated by the formation of 7 -methyl guanine in treated cocoa beans. Complete elimination of E. cautella was achieved by using C02 under high-pressure at 4 bar within 4 hours of exposure. A longer exposure time of 6 hours was needed to control A. Jasciculatus and T. castaneum at the same pressure. Complete elimination was also achieved at 7 bar within 4 hours of exposure or at 10 bar within 2 hours of exposure for controlling A. fasciculatus and T. castaneum. In the control treatments using normal air at 10 bar within 4 hours of exposure, the percent RIE (reduction in emergence) for E. cautella was only 3.33% whereas no mortality were found for T. castaneum and A. fasciculatus. Carbon dioxide under high-pressure treatments exhibited low possibility to effect the quality of the treated cocoa beans. Plants - Effect of carbon dioxide on Carbon dioxide - Physiological effect 2003 Thesis http://psasir.upm.edu.my/id/eprint/8499/ http://psasir.upm.edu.my/id/eprint/8499/1/FSMB_2003_3_A%20D.pdf text en public doctoral Universiti Putra Malaysia Plants - Effect of carbon dioxide on Carbon dioxide - Physiological effect Food Science and Technology Selamat, Jinap English
institution	Universiti Putra Malaysia
collection	PSAS Institutional Repository
language	English English
advisor	Selamat, Jinap
topic	Plants - Effect of carbon dioxide on Carbon dioxide - Physiological effect
spellingShingle	Plants - Effect of carbon dioxide on Carbon dioxide - Physiological effect Wahyudi, Teguh Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans
description	The potency of C0₂ gas as an alternative fumigant in controlling stored-product insects, its inhibitory characteristics on the growth of molds and mycotoxins production and quality changes of the treated cocoa beans have been evaluated in four consecutive research experiments. These experiments were focused on the use of high CO₂ concentration during fumigation and followed by prolonged storage practices in laboratory hermetic room, under plastic enclosures or high-pressure chamber. As comparison, treatments using methyl bromide, phosphine and normal air atmosphere were also carried out. Carbon dioxide concentration of 40, 60 and 80% were effective in controlling Ephestia cautella and Araecerus Jasciculatus during 1 to 3 months of exposure, whereas the test insects in the control showed 20-27 survivors for E. cautella and 20 surVIvors for A. Jasciculatus from the initial number of 30 and 20 insects, respectively. This study also found no significant effect of high CO₂ concentration treatments on cocoa beans quality during the exposure time. The growth of A. flavus and aflatoxins production (except for aflatoxin B2) was significantly inhibited in the presence of high concentration of CO₂ atmosphere during I-month storage. Free fatty acids production in the treated cocoa beans was not inhibited by the treatments. Methyl bromide concentration of 15 g/t or 0.66 g/t of phosphine were required to control E. cautella, A. Jasciculatus and Tribolium castaneum. Levels of methyl bromide residues increased from 0.27 ppm to 1.27, 1.49 and 3.10 ppm with an increase in concentration of methyl bromide from 3 g/t to 5,10 and 15 g/t, respectively. Phosphine residues increased from 0.07 ppm to 0.12, 0.11, 0.14 and 0.15 ppm with an increase in concentration of phosphine from 0.33 g/t to 0.66, 1, 2 and 3 g/t respectively. Methyl bromide fumigation resulted in methylation of proteins as indicated by the formation of 7 -methyl guanine in treated cocoa beans. Complete elimination of E. cautella was achieved by using C02 under high-pressure at 4 bar within 4 hours of exposure. A longer exposure time of 6 hours was needed to control A. Jasciculatus and T. castaneum at the same pressure. Complete elimination was also achieved at 7 bar within 4 hours of exposure or at 10 bar within 2 hours of exposure for controlling A. fasciculatus and T. castaneum. In the control treatments using normal air at 10 bar within 4 hours of exposure, the percent RIE (reduction in emergence) for E. cautella was only 3.33% whereas no mortality were found for T. castaneum and A. fasciculatus. Carbon dioxide under high-pressure treatments exhibited low possibility to effect the quality of the treated cocoa beans.
format	Thesis
qualification_level	Doctorate
author	Wahyudi, Teguh
author_facet	Wahyudi, Teguh
author_sort	Wahyudi, Teguh
title	Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans
title_short	Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans
title_full	Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans
title_fullStr	Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans
title_full_unstemmed	Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans
title_sort	effects of high carbon dioxide concentration on stored-product insects, aflatoxin production and storage quality changes in cocoa beans
granting_institution	Universiti Putra Malaysia
granting_department	Food Science and Technology
publishDate	2003
url	http://psasir.upm.edu.my/id/eprint/8499/1/FSMB_2003_3_A%20D.pdf
_version_	1747810819777757184

Effects of High Carbon Dioxide Concentration on Stored-Product Insects, Aflatoxin Production and Storage Quality Changes in Cocoa Beans

Similar Items