Presentazione sulla salmonella nel cioccolato: caso Ferrero

Bacterial stressors

Temperature

• pH

•

aw (water activity)

• Oxygen

•

Reduction potential

•

Hurdle tecnhologies utilize different obstacles for lower or remove bacteria.

à

Pathogenic bacteria activate stress response, permanent or transient. The stress

resistance can be stable into next generation.

Pathogenicity

Salmonella has several virulence factors, necessary to carry out all the various phases of

the infection.

Defense systems that allow survival in acidic pH environments

• Factors that intervene at the time of colonization of the intestine

•

Factors that allow it to cross the intestinal epithelium and survive in macrophages

• Salmonella has antigens:

of the bacterial body. They are thermostable and are made up of a protein, a

à

O

• phospholipid and a specific polysaccharide.

H fimbiae antigens. Are thermolabile and of a protein nature.

• à Vi not all Salmonella have it.

• à

Pathogenity about oxidative stress

The type III secretion system encoded in the Salmonella

pathogenicity island-2 (SPI-2) gene cluster protects the bacterium

from the antimicrobial activity of reactive oxygen species (ROS).

ROS generated in the innate host response stimulate transcription

of SPI-2 genes.

Oxidative stress stimulates Salmonella SPI-2 gene expression.

A, the induction of sifA gene expression by oxidative stress was 3. Food research international

https://www.sciencedirect.com/science/article/pii/S0021925822005713

determined by measuring the β-galactosidase activity of Salmonella

sifA::lacZY-expressing, aerobically grown in a stirring incubator in

low-Mg2+ N9 minimal medium.

H₂O₂ was added at the indicated concentrations for 30 min.

Salmonella and water activity…

Research was done regarding the survival and heat

resistance of a Salmonella cocktail in different chocolate

products.

Two levels of aw: 0.25 and 0.50

• Time: 12 months

• Temperature: 22°C

• Result: reduction of 4.19 log10 CFU/go

• (approximately). Greater reductions with aw 0.50.

Salmonella can survive in chocolate products for up to 12 2. Food research international

months and that its heat resistance has remained https://www.sciencedirect.com/science/article/abs/pii/S0963996923007548

relatively stable.

Non-thermal technologies for

decontamination

Many innovative ideas and technologies have been investigated

that can replace conventional thermal technologies used to

inactivate foodborne pathogens:

Cold plasma

• ight-emitting diode

• Ozone

•

4. Food research international Ultrasound

•

https://www.sciencedirect.com/science/article/abs/pii/S0924224421002697 Pulsed electric field

•

They ensure food freshness and also improve microbial safety and

food quality.

The scandal of Kinder

In April 2022 was discovered a Salmonella contamination. AFSCA (federal agency for

• food chain safety) decided to close the firm of Ferrero in Arlon (France). 300 5. Kinder eggs

children were affected by salmonellosis* and Ferrero has withdrawn in all

countries products suspected of being contaminated.

Last year (2023), Salmonella was found in the same factory in France. In this case,

• the production lines were stopped because the operators noticed it in time.

According to an epidemiological report by the European Centre for Disease

• Prevention and Control (ECDC), the Ferrero outbreak eventually affected 367 people. 6. Kinder schoko-bons

*salmonellosis diarrhea and abdominal pain, but fever, nausea, and vomiting are also possible.

à

Children and people with weakened immune systems are particularly at risk.

This an example of recall form of

ß

specific product.