MYCOTOXINS Procedures used to reduce presence of mycotoxins

MYCOTOXINS Procedures used to reduce presence of mycotoxins Control of mycotoxins should be focused within a program that is usually called “Integrated Control�.

This control consists of applying

GROWING FOOD

preventive measures in all phases of Selection of varieties Control of insects and pests Fertilization Rotation of crops Harvest period Collection procedure Cleaning Drying

feed production. The controls and measures to be implemented should become extended to the following area: Growing food Storage, transport and distribution

STORAGE, TRANSPORT AND DISTRIBUTION Pest control Moisture control Temperature control Cleaning of facilities

Feed contaminated

TREATMENTS OF FEED CONTAMINATED The measures to be applied may vary from mycotoxin to mycotoxin.

As for the industrial treatments of feed contaminated with mycotoxins is concerned, the following measures can be applied: Physical methods of elimination Physical methods of detoxification Absorption Biotransformation

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PHYSICAL METHODS OF ELIMINATION

CLEANING AND SEPARATION

DRY MILLING

WET MILLING

This method consists of

It is known that, during

elimination of the most

wet milling, aflatoxin B1

contaminated grains and

and zearalenone are mostly

fractions.

concentrated in washing water

In rice, 95% of aflatoxins are in the bran.

In wheat, most of aflatoxins

and in fiber. And, to a lesser

are located in peripheral areas as

Methods of manual separation,

extent in germ and gluten.

well.

methods of flotation and density

However, the resulting starch is

segregation can be used,

practically devoid of aflatoxins.

for example, for corn or for groundnut.

In corn, aflatoxins are primarily located in seed and in foliage,

It is an interesting procedure for

which is not the case with

obtaining starch, but not for the

zearalenone, since it can be

In corn, broken grains contain

“by-products� used in animal

found in all fractions.

more mycotoxins than whole

feed, in which, on the contrary,

grains.

the mycotoxins could undergo a

The drawback of these methods

process of concentration.

is based on the fact that they do

Therefore, the importance of dry separation is understood in case of certain items contaminated by aflatoxins.

not allow complete separation of the contaminated fractions.

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PHYSICAL METHODS OF DETOXIFICATION

THERMAL DEACTIVATION

IRRADIATION

Aflatoxins are quite resistant to temperature.

There is not much information about the effect of gamma and UV radiations based irradiation

They are not destroyed completely using

method on mycotoxins contaminated food.

procedures such as autoclaving, boiling, or other thermal processes.

Moreover, these processes are expensive and there is a reluctance on their application.

Aflatoxin M1 is stable during the pasteurization of milk.

In case of groundnuts, aflatoxins can be destroyed, for example, by frying in oil or dry roasting.

Microwave roasting also seems to be a good choice.

The fumonisin concentration decreases when foods are heat treated at temperatures higher than 150 °, although the total detoxification cannot be guaranteed.

There is also some data on partial removal of ochratoxins.

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ADSORPTION

Adsorption is a concept used in the field of physics referring to the process and the result of adsorbing.

It refers to the attraction and retention that one body makes on its surface of ions, atoms or molecules belonging to a different body.

It is one of the systems used for its excellence in the

MAIN ADSORBING AGENTS

process of preparing feed for animals.

Adsorbents must be able to bind mycotoxins present in the contaminated feed without dissociating from them during their journey through the gastrointestinal tract of the

Active carbon

animal, so that the mycotoxin-adsorbing agent complex can be eliminated through stool, thus minimizing animal exposure to mycotoxins (EFSA, 2009).

Silicates Silicates modified with organic compounds Yeast cell walls

BIOTRANSFORMATION

Another solution to relativize the harmful effect of mycotoxins is biotransformation, a cutting-edge mycotoxin deactivation method, which converts toxins into non-hazardous and less toxic metabolites.

This method is based on the fact that certain specialized microbes (bacteria, and yeasts) can use mycotoxins as nutrients and can convert mycotoxins to nontoxic forms. These bacteria use enzymes that break down mycotoxins.

The method of enzymatic biotransformation has been scientifically proven and there is already an enzyme authorized by the European Union, proven to biotransform fumonisins into non-toxic metabolites.

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