Assessment of ochratoxin A stability following gamma irradiation: experimental approaches for feed detoxification perspectives

2016 ◽  
Vol 9 (2) ◽  
pp. 289-298 ◽  
Author(s):  
A. Mehrez ◽  
I. Maatouk ◽  
R. Romero-González ◽  
A. Ben Amara ◽  
M. Kraiem ◽  
...  

The present study evaluated the effect of gamma irradiation on the stability of ochratoxin A (OTA) under various conditions. The effects of the physical state of OTA (solid vs aqueous), initial OTA concentration, irradiation dose and dose rate as well as the presence of model substances simulating food matrix compounds on OTA radiostability were investigated. First, pure OTA with and without food model compounds including α-D-glucose (monosaccharide), Methyl α-D-glucopyranoside (starch) and the amino acid derivatives N-α-acetyl-L-lysine methyl ester and N-α-acetyl-L-cysteine methyl ester (protein models) were irradiated with doses of 2, 4 and 8 kGy applied at 15.117 and 108.24 Gy/min. Secondly, artificially OTA-contaminated wheat with different moisture content (11, 14 and 16%) was irradiated with doses of 2, 4 and 8 kGy applied at 63.39 Gy/min. Residual OTA levels were analysed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry. Solid OTA (50 and 3,200 ng/ml)showed great irradiation stability, even with irradiation doses up to 8 kGy. Under dry conditions, the presence of food model components did not affect OTA radiostability. However, in an aqueous solution, complete reduction was achieved at the initial OTA concentration of 50 ng/ml and irradiation dose of 2 kGy. Applying gamma irradiation to cereal-based food model systems produced a significant OTA reduction (5,000 µg/kg) of 47.2% in moistened wheat kernels (16%) with an absorbed dose of 8 kGy but failed to reduce the OTA content of low moisture content wheat (11%). These model experiments offered a useful tool to assess the main key factors affecting gamma irradiation-induced OTA reduction. Gamma irradiation is promising since the irradiation doses applied could partially reduce OTA contamination. Nevertheless, its efficacy was largely affected by initial moisture content and could be dangerous if toxic by-products are produced or nutritive quality is lost and needs further study.

2006 ◽  
Vol 69 (5) ◽  
pp. 1139-1143 ◽  
Author(s):  
MIREN CASTELLS ◽  
ESTER PARDO ◽  
ANTONIO J. RAMOS ◽  
VICENTE SANCHIS ◽  
SONIA MARÍN

The objective of this work was to determine the effects of extrusion cooking on the stability of ochratoxin A (OTA) in an artificially contaminated hulled barley meal (0.73-mm grain diameter) using a single screw extruder. The extrusion cooking parameters were temperature (140, 160, and 180°C), initial moisture content of barley meal (24, 27 and 30%), and residence time (30, 40, 50, 60, and 70 s). Both unextruded and extruded samples were analyzed for OTA by high-performance liquid chromatography. Extrusion cooking variables significantly affected the stability of OTA (P < 0.05). Greater OTA reductions were achieved at higher residence time (70 s), medium temperature level (160°C), and either high (30%) or low moisture (24%) content of samples. The amount of OTA destroyed during the extrusion process ranged from 17 to 86% depending on the studied parameters. The decrease in the amount of OTA after extrusion cooking followed first-order kinetics, showing that the fastest treatment in OTA reduction was that at 140°C and 24% of moisture content.


Author(s):  
Weixia Zhong ◽  
Jiansheng Sun ◽  
Jinping Liu ◽  
Ping Sun

In this paper, irradiated samples by different irradiation doses of the beta/gamma radiation from a selected nuclear cable material, which were studied by tensile machine, DSC and DMTA. The research results show that the elongation at break (EAB) drops with absorbed dose of beta/gamma radiation and at the same dose the EAB drop for beta-irradiated samples is higher than that for gamma-irradiated samples, which means that this material becomes more brittler with more irradiation. The OITP value for the irradiated samples exhibits pronounced drop with absorbed beta/gamma irradiation dose. And moreover, the OITP value of these gamma irradiated samples drops faster than that of those beta irradiated samples. DMTA researches show that the storage modulus (E′) and the loss factor (tanδ = E″/E′, E″ represents the loss modulus) of the irradiated samples present higher values with the increase dose of beta /gamma radiation. It is interest that the E′ behaves firstly an increase, then decreases by rising the temperature within the temperature range of −30–20 °C, and this trend becomes pronounced with increase of irradiation dose, combined with the activation energy, correspond to the glass transition process, for all the irradiated samples which hints that the glass transition process may be hindered in terms of a higher activation energy, but the movement unit could be smaller with a lower Tg, as a result of the beta/gamma irradiation.


2014 ◽  
Vol 3 (4) ◽  
pp. 113 ◽  
Author(s):  
Di Stefano Vita ◽  
Pitonzo Rosa ◽  
Avellone Giuseppe

<p>The widespread contamination of food by mycotoxins may present a serious hazard to human and animal health. The gamma rays were applied to reduce ochratoxin A (OTA) and aflatoxins B<sub>1</sub>, B<sub>2</sub>, G<sub>1</sub> and G<sub>2 </sub>(AFB<sub>1</sub>, AFB<sub>2</sub>, AFG<sub>1</sub> and AFG<sub>2</sub>) in almonds artificially contaminated. In the present study we investigated the effect of gamma irradiation dosages, ranging from 0 to 15 kGy and the reduction of mycotoxins concentration in almond samples. In order to determine the efficiency of the method, a high-performance liquid chromatography method with fluorescence detection was used, the mycotoxins were extracted from almond samples and then purified with immunoaffinity columns. The maximum reduction was found at 15 kGy and it was 19.25%, 10.99%, 21.11%, 16.62%, 23.90% for AFB<sub>1</sub>, AFB<sub>2</sub>, AFG<sub>1</sub>, AFG<sub>2</sub> and OTA respectively. Results showed that gamma radiations even at 15 kGy, were not effective in completely destroying aflatoxins and ochratoxin A.</p>


2019 ◽  
Vol 82 (8) ◽  
pp. 1433-1439
Author(s):  
IMED MAATOUK ◽  
AMEL MEHREZ ◽  
AYA BEN AMARA ◽  
RAGOUBI CHAYMA ◽  
SALWA ABID ◽  
...  

ABSTRACT Gamma irradiation is a useful technology for degrading mycotoxins. The purpose of this study was to investigate the effect of irradiation on ochratoxin A (OTA) stability under different conditions. OTA was irradiated in methanolic solution and on millet flour at doses of 2 and 4 kGy. Residual OTA concentrations and possible degradation products in irradiated samples were analyzed by high-performance liquid chromatography with fluorescence detection and liquid chromatography coupled to mass spectrometry. The extent of in vitro cytotoxicity of OTA to HepG2 cells, with and without irradiation treatment, was assessed with an MTT assay. OTA was more sensitive to gamma radiation on Tunisian millet flour than in methanolic solutions. After irradiation of naturally contaminated millet flour, the OTA concentration was significantly reduced by 48 and 62% at a dose of 2 and 4 kGy, respectively. However, in the methanolic solution, OTA at concentrations of 1 and 5 μg mL−1 was relatively stable even at a dose of 4 kGy, with no degradation products detected in the chemical analysis. Analytical results were confirmed by cell culture assays. The remaining cytotoxicity (MTT assay) of OTA following irradiation was not significantly affected compared with the controls. These findings indicate that gamma irradiation could offer a solution for OTA decontamination in the postharvest processing chain of millet flour. However, the associated toxicological hazard of decontaminated food matrices needs more investigation.


Author(s):  
L. Hübschen

AbstractThe present paper shows the detectable factors on which a sorption isotherm depends. Even if it is well-known that a sorption isotherm is most essentially conditioned by influences of the respective tobacco variety, other factors, such as temperature, initial moisture content, or fibre dimension, play a part as well. In general, a sorption isotherm constitutes a ''summation'' of such factors and, in the end, a combination of desorption and adsorption if the tobacco is dried or moistened from the average commercial moisture content. The tobacco hysteresis is experimentally investigated and discussed


Agrotek ◽  
2018 ◽  
Vol 2 (6) ◽  
Author(s):  
Wilson Palelingan Aman

<em>A research about cocoa beans drying used solar tunnel dryer with photovoltaic module driven have conducted in Manokwari. Solar tunnel dryer used in this research adapted from type Hohenheim with photovoltaic module and integrated air heat collector has been installed at the Department of Agricultural Technology, Papua State University Manokwari to dried cocoa beans. The objectives of this research were to design solar tunnel dryer and evaluate it�s performance in dryed cocoa beans. The result obtained was a new construction of solar tunnel dryer for cocoa beans with dimensions 6 m of length and 0,9 m of wide. The dryer completed with photovoltaic module to drive the blowers of hot drying air. �Performance test of the dryer showed that drying of 10 kg of cocoa beans with initial moisture content about 70% wet basis needed 13 hours of drying time to achieved final moisture content about 7,17% wet basis. The drying time achieved was faster compared than traditional solar drying that needed 20 hours of drying time. The maximum temperature achieved in drying chamber was 60 <sup>o</sup>C.</em>


Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1590 ◽  
Author(s):  
Angelo Del Giudice ◽  
Andrea Acampora ◽  
Enrico Santangelo ◽  
Luigi Pari ◽  
Simone Bergonzoli ◽  
...  

Drying is a critical point for the exploitation of biomass for energy production. High moisture content negatively affects the efficiency of power generation in combustion and gasification systems. Different types of dryers are available however; it is known that rotary dryers have low cost of maintenance and consume 15% and 30% less in terms of specific energy. The study analyzed the drying process of woody residues using a new prototype of mobile rotary dryer cocurrent flow. Woodchip of poplar (Populus spp.), black locust (Robinia pseudoacacia L.), and grapevine (Vitis vinifera L.) pruning were dried in a rotary drier. The drying cycle lasted 8 h for poplar, 6 h for black locust, and 6 h for pruning of grapevine. The initial biomass had a moisture content of around 50% for the poplar and around 30% for grapevine and black locust. The study showed that some characteristics of the biomass (e.g., initial moisture content, particle size distribution, bulk density) influence the technical parameters (i.e., airflow temperature, rate, and speed) of the drying process and, hence, the energy demand. At the end of the drying process, 17% of water was removed for poplar wood chips and 31% for grapevine and black locust wood chips. To achieve this, result the three-biomass required 1.61 (poplar), 0.86 (grapevine), and 1.12 MJ kgdry solids−1 (black locust), with an efficiency of thermal drying (η) respectively of 37%, 12%, and 27%. In the future, the results obtained suggest an increase in the efficiency of the thermal insulation of the mobile dryer, and the application of the mobile dryer in a small farm, for the recovery of exhaust gases from thermal power plants.


2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Monika Aniszewska ◽  
Krzysztof Słowiński ◽  
Ewa Tulska ◽  
Witold Zychowicz

AbstractThe paper proposes the use of microwave irradiation to lower the initial moisture content of wood chips. The study involved willow and fir chips fractionated by means of a sieve separator and unfractionated ash chips. The wood chips were exposed to a constant microwave power of 800 W for 30 s, 60 s, 120 s and 180 s. The chips were weighed before and after irradiation to measure loss of moisture. It was found that the decline in moisture content increased with wood chip size for a given irradiation time and microwave power. The initial moisture content of wood chips was not found to significantly affect loss of moisture as the drying rates of wood chips with higher and lower moisture content exposed to microwaves were not statistically different. The results showed that irradiation intensity increased with the time of exposure to microwaves and unit radiant energy per unit of evaporated moisture decreased with increasing wood chip size in the 3.15–31.50 mm range.


Horticulturae ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 40
Author(s):  
Vincenzo Alfeo ◽  
Diego Planeta ◽  
Salvatore Velotto ◽  
Rosa Palmeri ◽  
Aldo Todaro

Solar drying and convective oven drying of cherry tomatoes (Solanum lycopersicum) were compared. The changes in the chemical parameters of tomatoes and principal drying parameters were recorded during the drying process. Drying curves were fitted to several mathematical models, and the effects of air temperature during drying were evaluated by multiple regression analyses, comparing to previously reported models. Models for drying conditions indicated a final water content of 30% (semidry products) and 15% (dry products) was achieved, comparing sun-drying and convective oven drying at three different temperatures. After 26–28 h of sun drying, the tomato tissue had reached a moisture content of 15%. However, less drying time, about 10–11 h, was needed when starting with an initial moisture content of 92%. The tomato tissue had high ORAC and polyphenol content values after convective oven drying at 60 °C. The dried tomato samples had a satisfactory taste, color and antioxidant values.


2021 ◽  
Vol 125 ◽  
pp. 215-219 ◽  
Author(s):  
Nisha N. Gurusamy ◽  
Natalie Puffer ◽  
Coen de Jongh ◽  
Cristina Rodriguez Gil ◽  
Thomas J. Aspray

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