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Prof. Valerio Giaccone explores the use of natural casings in food production, emphasizing their safety and importance. Learn about hazards, risks, and microbial pathogens associated with foodborne illnesses.
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Natural casings and food safety: an up-to-date Valerio Giacconce School of Veterinary Medicine – University of Padua (Italy)
Who I am My name is Valerio Giaccone Full professor of “Meat Hygiene and Food Inspection”
Who I am My Collegues say I am … … the “Food detective”
Who I am I would like to be called … … the “Food Doctor”
As Doctor … … I should make everything to keep the food “safe” … … and keep away every possible “hazard”
Arguments What we know on casings What we should better understand What we should discover
What we know on natural casings?
We know that … … natural casings are worldwide used as “skin” … … for various kind of sausages and other foods
We know that … … the commercial trade of natural casings on the world … … plays a considerable economic role
Houben (2005) “In 2002 the total EU foreign trade in natural casings … … was about 1.4 billion dollars”
Koolmees (2004) He reports that the trade of natural casings … … is estimated in 2.5 billion dollars per year
We know that … … the 60% of natural casings used for sausages … … comes from the small intestine of sheep
Natural casings … … are drawn from the submucosa of animal gut … … by desliming and stripping off their mucous and muscular layers
Natural casings … … are usually prepared by salting, curing and drying … … various part of animal gut
Hazards for human health
First HAZARD and RISK … … ARE NOT THE SAME THING
An hazard … … is a physical, chemical or biological agent … … which can be dangerous for human health
An hazard … … is always an hazard … … aside from the food
For example Ice cream contains a lot of air (and of Oxygen) Clostridium botulinum grows only in strict anaerobiosis
For example Clostridium botulinum is an hazard for ice cream ? YES, because it can cause botulism in humans
Nevertheless … … the probability that C. botulinum grows in ice cream … … is very low, because the presence of too much oxygen
The risk A risk is the mathematical probability … … that an hazard can occurr
Microbial pathogens Kind of hazard Chemical residues
Bacteria Toxigenic moulds Microbial hazards Viruses
Natural contaminants Chemical hazards Xenobiotic contaminants
Microbial pathogen Salmonella enterica Campylobacter Listeria monocytogenes Escherichia coli VTEC
Chemical residues Heavy metals Antibiotics & chemoterapics Pesticides Mycotoxins (ochratoxin)
Microbial pathogen In 2009 in European Union occurred more than … … 190.000 cases of human foodborne campylobacteriosis
Microbial pathogen In 2009 in European Union occurred more than … … 108.000 cases of human foodborne salmonellosis
Microbial pathogen In 2009 in European Union occurred … … 1.645 cases of foodborne human listeriosis
Foodborne diseases 2009 The EU Summary Report “Trends and Sources of Zoonoses and Zoonotic Agents and Food-borne Outbreaks in 2009”
What we know Natural casings are not a substantial source … … of foodborne pathogens for sausages
As consequence Natural casings are microbiologically fully acceptable … … if they are adequately dry-salted
What we know Very rarely natural casings harbor Salmonella, … … Listeria monocytogenes or other microbial pathogens
Why ? Because their production process and … … because the antimicrobial action of salting and curing
The pathogens They are normally harbored in gut of animals, so they … … could pass to natural casing in the first production steps
But … … … by salting, curing and drying the gut for at least 30 days … … it is very rare that Salmonellae and other pathogens can survive
Clostridia Sulphite-reducing Clostridium are sometimes detected in natural casings They produce high resistant “spores” which survive in salt
Bacillus The same risk can occorr with spores of Bacillus cereus … … another cause of foodborne intoxication
Nevertheless … … the risk for sausages … … comes from the alive clostridia, NOT from spores
We know that … … the alive Clostridia CAN NOT grow in natural casings … … because their salt content
An experience of challenge test
Aim of the study Inspired by Bailocom, we have performed a challenge test … … to study the behaviour of Clostridia in natural casing
The numbers We have analysed 120 samples of natural casings … … looking for the charge of sulphite-reducing Clostridium
The numbers The 30 casing in which we found the most high charges of Clostridium … … were then used to produce raw seasoned sausages
The tests 21 sausages at the begin of seasoning and other … … 21 sausages at the end of seasoning were analysed
The results In all samples tested we have found charges of Clostridium … … always below 10 cfu/g of meat
What does it means? Natural casing can contain low charges of Clostridium spores … … but the spores have no real significance for the sausage
What we should better understand
Viruses Certain viruses, pathogenic for breeding animals, may persist … … in adequately salted casings