An excerpt from the report by Dr. Alexandra Makulla -
Press office of the Federal Biological Research Centre for Agriculture and Forestry.

Published by iwd - Informationsdienst Wissenschaft, News, Dates, Experts

In June 2001, 30 experts from six countries met at the Federal Biological Research Centre for Agriculture and Forestry in Braunschweig. The topic of the meeting was "the hygienic properties of wood and wood products, especially in connection with possible infestation by bacteria and fungi".

It was agreed that the reputation of wood in food processing must be rehabilitated.

What our ancestors knew and was part of everyday knowledge was buried by the enthusiasm for new materials. This ancient knowledge must now be rediscovered by science. "Bacteria only grow at a slower rate on wooden boards" To our surprise, it was shown that the hygiene properties of wood in particular are much better than previously assumed. Pine wood has - in contrast to plastics - antibacterial properties.

The original text can be read at idw-online.de/de/news36650.

It is often recommended in the Kitchen ABC, and many people do it: for reasons of hygiene, different chopping boards should be used in the kitchen for fruit and vegetables and for meat. This measure is intended to prevent harmful bacteria and germs, such as salmonella or Escherichia coli, from being transferred from meat to fruit and vegetables and thus ending up in the (raw) food. It is also intended to prevent the contamination of meat with pesticides, which may not be completely washed off from fruit and vegetables.  The cutting boards used also play an important role in the considerations. Plastic chopping boards are generally considered easier to wash and therefore more hygienic than wooden ones. The bESSERwisser investigated this myth and asked: Is this really true - are plastic chopping boards preferable to wooden ones?

Wood versus plastic:

For a long time, wood was THE material for tableware, cutlery and storage containers. With the introduction of plastics, however, the view that wood was unhygienic became more and more widespread - wood was long said to have poor cleaning properties in particular. Since wood is more porous than plastic, it was long assumed that harmful germs could settle better in it, and wooden utensils were thus considered unhygienic. This also led to corresponding legislation - for example, wood was banned or at least its use severely restricted in many national and European laws and directives in connection with food. But studies prove: the opposite is the case, wood has an antibacterial effect.

Why wood is strong against bacteria:

Studies [1-3] have shown that wood has an antibacterial effect due to the tannins (tannins) it contains. Pine wood is the biggest germ killer, but larch and oak also have similar antibacterial properties. The germicidal effect of wood is constantly renewed, as fresh cut marks in the wooden board release antibacterial substances again.

In addition to the chemical component, the physical properties of wood also contribute to its antibacterial effect. In the past, the porous structure of wood was presented as a disadvantage compared to plastic, but today we know different things about it:  With its large surface area, wood has a strong hygroscopic effect. Due to its cellular nature, wood deprives bacteria of the moisture they need to live, and they die.

Cleaning and renewal:

Washing by hand instead of in the dishwasher has not proven to be a hygienic concern with either wooden or plastic boards. Only odours (e.g. from onions) can be removed better in the dishwasher. In any case, it is important that the boards are well dried, because most pathogens are not resistant to drying. For wooden boards, it is sufficient to wash them thoroughly in cold water and then rinse them with hot water.

Boards that are already scratched, especially those made of plastic, should definitely be disposed of. They are heavily contaminated with germs because food residues and bacteria stick to the rough surface and cannot be completely removed even when rinsed.

Regardless of whether they are made of wood or plastic: from a hygienic point of view, it is highly recommended to use different boards for meat/fish and for vegetables/raw vegetables. Bread should also have its own board. Also: always rinse cutting boards with hot water immediately after use!

References:

[1] Schönwälder A. et al.: Wooden boards affecting the survival of bacteria? Wood as a Raw Material (2002), Volume 60, Issue 4, pp 249-257

[2] Ak N. O. et al:. 1994. cutting boards of plastic and wood contaminated experimentally with bacteria. J. Food Protect (1994)57: 16-22.

[3] Ak, N. O. et al: Decontamination of plastic and wooden cutting boards for kitchen use. J. Food Protect (1994). 57: 23-30,36.

Published with the kind permission of "Open Science - Lebenswissenschaften im Dialog".

Here is the link to the original text:
www.openscience.or.at/hungryforscienceblog/schneidbrett-hygienischer-aus-holz-oder-plastik/