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During cheese-making the bacteria are added to certain cheeses such as Emmental (also known as Swiss) and Leerdammer, and when warmed bubbles of carbon dioxide form in the cheese. These bubbles then become the distinctive holes (or eyes) in the finished product. This bacteria can also get you dizzy and sick for a couple of weeks or 2.
What else can I help you with?
What is Propionibacterium shermanii?
Propionibacterium shermanii is a species of bacteria commonly found in fermented dairy products like Swiss cheese. It plays a role in the production of propionic acid, which contributes to the flavor and texture of the cheese. Additionally, P. shermanii is considered a beneficial bacteria for its probiotic properties.
What is the optimum pH and temperature for growth of Propionibacterium shermanii?
The optimum pH for growth of Propionibacterium shermanii is typically around pH 6.5-7.0. For temperature, it grows best at around 30-37°C. These conditions are favorable for the growth and metabolism of Propionibacterium shermanii in various applications such as food fermentation.
When was propionibacterium shermanii discovered?
refer this paper www.pubmedcentral.nih.gov/articlerender.fcgi?artid=186833
What is p shermanii?
During cheese-making the bacteria are added to certain cheeses such as Emmental (also known as Swiss) and Leerdammer, and when warmed bubbles of carbon dioxide form in the cheese. These bubbles then become the distinctive holes (or eyes) in the finished product. This bacteria can also get you dizzy and sick for a couple of weeks or 2.
What microbe are in cheese?
There are sometimes many microbes in cheese or there is only a few, it is dependent on the type of cheese. Lactococci, Lactobacilli, Streptococcus, Propionbacter Shermanii. Brevibacter Linens and Pecilleum are responsible for some famously good cheeses.
How do they get the vitamin B12 into Marmite?
If you want to know the details of the process... sorry, I can't find that. I do note that the producers of Marmite list B12 as a separate ingredient, meaning they specifically add it as opposed to it being a normal part of the "yeast extract."At a guess, it's produced by bacterial fermentation from some bacterial species that produces it naturally... something like Streptomyces griseus, Pseudomonas denitrificans, or Propioniibacterium shermanii. S. griseus was at one time thought to be a type of yeast, but it's now known that no animals nor plants, including yeast, are capable of making Vitamin B12. Only bacteria, which are neither animals nor plants (but are still considered "vegan" food sources), can do this.Complicating this a bit is that some plants are capable of producing compounds that are similar enough to vitamin B12 that they actually test positive on the common B12 test, but these compounds are not biologically active... they're not "really" vitamin B12, they're just similar enough to fool the test.Marmite adds supplemental B12 presumably because they realize this. B12 is produced by bacteria that live in the intestinal tract of animals, so there's B12 in meat, but vegans have a real hard time getting enough B12. They have an easy time getting B6, and that can help mask the B12 deficiency to some extent, but there's a significant risk of mental/neurological deficiencies if they don't get B12 from somewhere.
Why does some cheese have holes?
Cheese (all cheese that is) is made by adding bacteria to milk, which produces lactic acid and helps give the cheese its taste. One specific bacteria added to Swiss cheese called Propionibacterium shermani produces carbon dioxide. Due to the density of the cheese, the carbon dioxide forms bubbles, which get larger and eventually burst, leaving the trademark holes.More recent research suggests that these bubbles form around microscopic debris in the milk, which compromises the structure of the cheese in those spots. Swiss cheese has gotten less holey over the years, and some scientists credit that to cleaner modern milking methods—fewer particles means fewer holes.Cheesemakers call these holes "eyes" and can control their size by adjusting the temperature, acidity, and curing time of the cheese.
How do you make Swiss cheese?
The following was copied from the eHow website.Things You'll Need1 gallon of whole milk, 1/2 packet of direct-set thermophilic starter or 2 ounces of prepared thermophilic starter, 1/2 teaspoon of propionic shermanii powder, 1/4 teaspoon of liquid rennet or a 1/4 renbet tablet, 1 pound of cheese salt, for brine, plus a pinch of cheese salt, 1/2 gallon of cold water, for brine. curd knife, stainless steel whisk, cheesecloth. ladleSwiss Cheese1 Heat the milk to 90 degrees Fahrenheit. Add the starter and mix well.2 Remove 1/4 cup of milk from the pot and add the propionic shermanii to it. Mix thoroughly to dissolve the powder. Add the mixture to the milk and stir. Cover and allow the milk to ripen for approximately 10 minutes.3 Make sure that the milk's temperature ALWAYS remains at 90 degrees. Add the diluted rennet and stir gently with an up-and-down motion for approximately 1 minute. If you are wanting to use farm fresh cow's milk, top stir for several minutes longer. Cover and let the milk set at 90 degrees for approximately 30 miutes.4 Using a curd knife and a stainless-steel whisk, cut the curd into 1/4 inch cubes.5 Keeping the curd temperatures at 90 degrees, gently stir the curds for approximately 40 minutes. This is called fore-working and helps expel whey from the curds before they are heated.6 Heat the curds by one degree every minute until the temperature is 120 degrees Fahrenheit. This will take approximately 30 minutes. Maintain the temperature at 120 degrees Fahrenheit for another 30 minutes, stirring often. The curds must be cooked until they reach a stage called the "proper break." To test for this, wad together a handful of curds and rub it gently between your palms. It the ball readily breaks apart into individual particles, the curds are sufficiently cooked. If they are not sufficiently cooked, they will be too soft to hold the cheese together. Let the curds set for approximately 5 minutes.7 Pour off the whey and reserve it for other recipes.8 Line a 1 pound mold with cheesecloth and place it in the sink or over a large pot. Quickly ladle the curds into the mold. You do not want the curds to cool. Press at 8-10 pounds of pressure for approximately 15 minutes.9 Remove the cheese from the mold and gently peel away the cheesecloth. Turn over the cheese, re-dress it, and press at 14 pounds of pressure for 30 minutes.10 Repeat the process but press at the same pressure of 14 pounds for 2 hours.11 Repeat the process but press at 15 pounds of pressure for 12 hours.12 Make a saturated brine bath by combining the salt and water in a noncorrosive pot; stir well. Remove the cheese from the mold, peel away the cheesecloth, and soak the cheese in the brine. Sprinkle the remaining pinch of salt on the surface of the floating cheese. Refrigerate the brine and let the cheese soak for 12 hours.13 Remove the cheese from the brine and pat dry. You can reserve the brine for other recipe uses if you so desire. Place the cheese on a clean cheese board and store between 50 to 55 degrees Fahrenheit and at 85 percent humidity. Turn the cheese daily for one week, wiping it with a clean cheesecloth dampened in salt water. Do not wet the cheese.14 Place the cheese in a warm, humid room, such as the kitchen, with the temperature between 68 and 74 degrees fahrenheit. Turn it daily and wipe it with a cheesecloth dampened in salt water. Do not wet the surface of the cheese. Let the cheese set for 2-3 weeks, until eye formation is noticeable. The cheese will swell somewhat and become slightly rounded.15 Age the cheese at 45 degrees Fahrenheit. and at 80 percent humidity for at least 3 months. Turn the cheese several times a week. Remove any surface mold with cheesecloth dampened in salt water. A reddish coloration on the surface of the cheese is normal and should not be removed.This recipe will make about 1 pound of cheese. If you an additional pound, just double the recipe.
