Identification of bacterial species.

Questions about the identification of certain bacterial species are rising time after time. Paper mills - and their customers - are interested to know if the product, paper or board, contains harmful bacteria like food-poisoning bacteria, or even hazardous ones. Could terrorists inoculate a paper machine with Bacillus anthracis? Could Listeria live in wet end processes? Bird-flu?

Another reason for the question is the safety of working environment. Are high densities of bacteria in the wet end air dangerous?

Fortunately all information of the environmental needs, growth factors and capability to survive dry end treatment (="pasteurization") show that there is no need to worry if those real pathogens could be encountered in paper industry products.

There are still some areas inside paper mill where the identifications are needed, like

* food-poisoning, sporeforming bacteria (most important: Bacillus cereus)
* bacteria causing raw material breakdown (amylolytic ones etc.)
* potential primary attachers, causing biofilm formation (several genus)
* bacteria which can cause health symptoms and diseases(Legionella pneumophila, certain coliform bacteria)

Identification of specified bacteria from wet end population isn't easy task. Mixed population, sample matrix, low number of target organisms, their distribution inside the machine all lead to very challenging task.

I will refer the traditional and novel methods for the detection of specified bacteria in next posts. Coming back...

Better housekeeping for paper machines.

There has been definitely some improvement in the microbiological control of paper machines since late 1970's (when IM started his work for it). As a very short review, two issues have been highlighted because their positive effect on the hygiene and driveability of machines: application of oxidative agents as biocides and biofilm research. Rapid killing of microbes in strategic sites of processes with compounds like peracetic acid, chlorine dioxide and ozone have given very promising results when the overall load of microbes inside machines shall be dropped. Better understanding of the features of biofilms - essential changes of bacterial metabolism when they attach on surfaces from flowing water and start to release more and more living cells and spores back to the process  - also help to focus attention on them.

Poor interests to invest in better analytical control of microbial activities, in opposite, is surprising, however. Why do the mills not benefit the obvious progress of such control methods like ON LINE luminometry, rapid PMEU incubations etc.? Is it a question of lacking knowledge, lacking interest or the status of old-fashioned analytical methods, not suited to rapid QC/HACCP of paper and board processes? Is microbiology regarded as the unknown living creature on the surface of "Solaris" in the novel of S.Lem (the most excellent film by Andrei Tarkovsky recommended!)

IM has been relatively frustrated for this situation but tries to think optimistic: some small-scale simulations are already running today, and more and more people with technical background have been interested to know about tools to estimate and forecast microbiological events inside their machines. Happy to hear that they understand that with costs of only a couple machine rolls they could have improved microbiological control which can lead to remarkable spare of money when preventing unexpected machine stops or claims of poor product quality by customers.