Posted on 03/22/2007 12:54:42 PM PDT by bd476
Food fight: Cheese bacteria fight off viral attacks
By Julie Steenhuysen
Reuters
CHICAGO Mar 22, 2007 - Scientists have found a way to ensure starter cultures used to make cheese can ward off attacks from bacteria-eating viruses -- a finding that could mean the difference between a great Gouda and wasted milk.
Attacks by viruses known as phages pose a particular problem for companies like Danish food ingredient maker Danisco, whose starter cultures are used in about half of all the ice cream and cheese produced in the world.
"Phages are one of the major causes of product failure for the food industry, especially in the dairy industry," said Philippe Horvath, a scientist at Danisco's laboratory in Dange-Saint-Romain, France.
The tiny viruses that infect bacteria enter the cell and rapidly replicate until the cell ruptures, spreading the virus in a series of repeating cycles.
"It's an explosive propagation," he said in a telephone interview.
Horvath and colleagues at Danisco have discovered how to harness bacteria's own natural defense mechanisms to produce phage-resistant bacteria. They reported their results in Friday's issue of the journal Science.
The study helps explain the role of a new family of repetitive sequences in the genome of bacteria called CRISPR sequences. They resemble some of the DNA sequences in the phages.
"LET NATURE DO THE WORK"
In computer models, scientists proposed that the CRISPR sequences allow bacteria to hijack a bit of the virus' genetic code, helping it to fight off attacks.
"Our results are the first biological demonstration that CRISPR provides a resistance against phages," Horvath said.
The researchers tested their theory on Streptococcus thermophilus, a bacteria used in making cheese and yogurt.
They were able to manipulate the DNA within the bacteria, adding a new spacer that gave it immunity against the attacking virus.
"We replicated what happens naturally in the lab using molecular biology tools. We've also shown that when we artificially take them out, the bacteria loses resistance," Horvath said.
Although the Danisco researchers could use the finding to produce genetically modified starter cultures for cheese and yogurt, they will not, out of respect for concerns over genetically modified organisms or GMOs in foods.
"We'll let nature do the work for us by simply challenging the bacterium with the phage," he said.
Then, they will simply choose the resistant bacteria for their cell cultures, he said.
"That's what cheese is—gone off milk with bugs and mold. That's why it tastes so good"
Gareth Blackstock in Chef!
IMO, nothing compares to Danish Blue. I prefer my own taste tests.
I find many of the best brands at Sam's. Their cryovaced beef is excellant. We buy entire strip loins or top sirloins and cut them ourselves as we prefer. We also buy entire cold smoked salmon at $14/lb. It is excellant. They carry very good brands of wine and liquor, often in presentation bottles. Sam's makes volume purchases of the very same goods of the very same quality in the very same packaging available in many other shops and it is this volume purchase and the warehouse merchandising that determines the price.
I can find the same Danish Blue in small quantities at one of the area supermarkets, but at Sam's, I can get a full pound at a much better price per ounce.
From a May 06 review on Danish Blue cheese as compared to Gorgonzola, Stilton, and Roquefort
"Danish Blue cheese is for folks who don't like blue cheese. Not that it is bad or anything, it just fails to impress. Not as tangy. Not as moldy. Not as earthy. Not as creamy."
I have some Danish blue in my refrigerator as we speak. It was on sale. I do enjoy it but I agree with the comparison as I have tasted those also. Other than the American grade cheeses you spoke of, have you compared Danish Blue to the three mentioned?
Blessed are the cheese makers.
L
Thanks, bfl
Errh, you're welcome neverflem. ;-)
Thanks! I'm going to do a bit of searching around for some good BLUE.
The cheese makers?
Ewww. Are they a particular kind of mite or would any mite do?
Cutting the cheese is now beneficial. Its healthy.
Do Over!
What's so special about the cheese makers?
Thank you! So glad to see that make it to YouTube!
Some Blue Cheese History:
Most of these cheeses were originally produced in caves in their respective areas, where the mold was naturally present. This combined with the unique nutrients that the mold grew on in the caves affected the flavor, texture and blue-green color of the mold in each of these cheeses. In the beginning, this was most likely discovered by accident when cheeses were stored in the caves, and they developed mold. Then someone decided to taste the cheese that others might have thought to be ruined, and realized how exquisite the taste had become.
Some blue cheeses, such as Danablue, were developed later as less expensive alternatives to the higher priced Roquefort cheese from France.
The process for making America's ‘Maytag Blue Cheese’ was developed by the Iowa State U. in 1941 (it is a process for making blue cheese with pasteurized milk.) Production was begun by Fred Maytag II (of dishwasher fame) when he heard about the new process. Maytag blue is also aged in specially designed caves.
http://www.foodreference.com/html/artbluecheese.html
I've got a slice of this Bad Boy (Stilton Blue) in my fridge right now. My husband repairs computers, and one of his clients owns a cheese shop. On those service calls he gets paid in dollars AND cheese as the owner always offers him something from the case. He has come home with 4 year old sharp Cheddar, White Cheddar Cheese Curds, this Stilton, and just about any cheese you can name. Life Is Good! :)
Monty Python..."The Life of Brian."
There's also some disagreement as to whether "the meek" or "the Greek" shall inherit the Earth. ;)
"Did you hear that? Blessed are the Greek."
"The Greek?"
"Well apparently he's going to inherit the earth."
"Did anyone catch his name?"
That's why the Mooses like it so much!
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