Why mozzarella turn blue?

They had called the “mozzarella of the Smurfs” because, in contact with the air, become blue. – They explained to investigators – behaved well, working with the police and angling to pick up all the pieces entered service.

The Agriculture Minister Giancarlo Galan, has called on the Chamber of Deputies to approve urgently the law on labeling “to ensure all consumers”. “half of the mozzarella for sale in Italy are made with foreign milk curds or even industrial (semi) from abroad”. “between blue mozzarella, milk to melanin, tomatoes fake from Eastern Asia and Oils Import passed off as Italian national agriculture really do not take it anymore”.
Later, also in Bari, a batch of 13 tons of mozzarella 'blue’ and’ been subject to constraint by the Core Antisofisticazioni precautionary health care of the police in Bari in a large distribution center in Molfetta. ’ called the mozzarella from the market. & Co.

These are the facts, but because the mozzarella turn blue?

The mozzarella can be contaminated during the latter stages of processing by strains of a bacterium, "Pseudomonas", capable of producing fluorescent pigments. Pseudomonas fluorescens are those who play the main role in the alterations of color. P. , Which causes a green color due to the production of pyoverdin, and P. which gives a blue-green color due to production of pyoverdin and another blue pigment. read this recent Chronicle article): There is another strain, Pseudomonas putida which secretes the "ferrazina", a pigment that imparts a yellow-orange-red.

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