Foodbuzz 24x24:Bacteria, Yeast, and Mold

My job involves working with Food Scientist and Engineers and when I told them about the theme “Bacteria, Yeast, and Mold” a lot of them thought “Yum!”  Yes, I am fortunate to work with a lot of talented individuals that enjoy and appreciate the wonders of good bacteria, yeast, and molds which help to produce foods that we eat every day.

Some of my friends searched the Internet in hopes to find some creative help with their dishes and found websites with cautionary warnings of “if there are microbes in the food, do not eat it,” or “foods to stay away from.”   Here’s some of the foods that we enjoyed on Saturday and a brief description of the bacteria, yeasts, and molds that took center stage. 

Beer:  Yeast used in beer brewing process
Beer is brewed using brewing yeasts such as Saccharomyces cerevisiae and Saccharomyces pastorianus,  Just like the use of yeasts in bread, the yeast break down carbhoydrates into simple sugars, which are fermented and form carbon dioxide and alcohol.
Also sneaking into the picture is a big bottle of kimchi(fermented cabbage)Also sneaking into the picture is a big bottle of kimchi(fermented cabbage)

 Sangria:  Yeast used to make the wine.
The wine-making process is similar to beer in that sugars are converted into alcohol with the use of yeast.  Different kinds of yeast are commonly found on grape skins, and these naturally occurring yeasts results in unique flavor profiles. 


As you can see a few people were extremely creative and tried to include as many different types of bacteria, yeast, and mold into their food creations.  



Sourdough, Sausage, and Smoked Gouda Stuffed Mushrooms: Bacteria (sourdough bread), Lactic Acid Bacteria(Sour Cream), Beer (Yeast), (Fermented Sausage), Probiotic Bacteria (Smoked Gouda). 

Spinach and Sour Cream Dip in a Sourdough bread bowl

Sourdough Bread: Lactobacillus bacteria and yeast are used in the sourdough making process. Lactic acid is produced when the carbohydrates (i.e. flour, sugars) are broken down into simple sugars and then fermented.  This lactic acid sour flavor to the bread, hence “sour” dough.   

On a sidenote, there is even a specific organism that produces the distinct San Francisco sourdough bread flavor. Lactobacillus sanfranciscensis. 

Beer and Cheese Dip 

 Blue Cheese Chips: I attempted to make a warm blue cheese sauce to drizzle over kettle chips.  It didn't taste as good as Ken Rathburn's appetizer, but it wasn't bad.  Blue cheese is a veined cheese with a strong flavor.  Penicillium mold and other bacteria (i.e. Brevibacterium linens) can be added to the cheese  and is the contributing factor to the blue/gray color mold, strong odor, and sharp flavor of the cheese.

Baked Brie with Raspberry Jam and Cranberries :A soft cheese that is innoculateThe cheese is then taken out of the molds, salted, inoculated with a Penicillium mold and then aged.

Spanish Fermented Sausage and Iberia Sheep's Milk Cheese

Mixed Greens with Blue Cheese, Strawberries, Grape Tomatoes and Candied Pecans

Home-Made Bread: 
Yeast (i.e. Saccharomyces cerevisiae) is used in yeast breads as a leavening agent.  Carbohydrates and sugars serve as a source of food for the yeast, and the yeast ferments the sugars  in low-oxygen conditions.  The gas that is produced is trapped in the gluten structure of the bread dough proteins, and results in the air pockets that contribute to the soft airy texture of breads. The dough is then baked, the yeast die and the pockets of air are set and provide the structure of bread.  

Shiner Bock Cheesy Beer Biscuits  

 Teriyaki (with Soy Sauce) Corn: 
Soy sauce is made using a combination of Aspergillus molds, Saccharomyces cerevisiae, Bacillus, and Lactobacillus species.  Soy sauce is produced by fermenting soybeans with Aspergillus molds.  
Over time, the Aspergillus mold breaks down the soy and wheat into sugars and proteins and then lactic acid bacteria ferments the sugars and yeasts produced alcohols. The strong flavors of soy sauce develop through the fermentation and aging of the solution.   The soy sauce is pasteurized to kill any active yeast, bacteria, and/or molds remaining from the soy sauce making process.

 

Guinness Beer Brats with Sauerkraut

Sauerkraut is a fermented cabbage product that is produced with the help of anaerobic (does not need oxygen to live) and lactic acid bacteria.  The lactic acid breaks down the sugars in cabbage and results in a sour pickled flavor.  The production of a lot acid results in a highly acidic food that helps to deter or precent the growth of “bad; organisms such as Clostridium botulinum.

Kimchi (Fermented Cabbage)Bulgogi Burgers (marinade has soy sauce): 
Kimchi is made using lactic acid bacteria, similar to the sauerkraut process. 

Reuben Sandwich-Corned Beef, Sauerkraut, Swiss Cheese, Thousand Island Dressing, and Rye Bread:  Swiss cheese is produced using three bacteria  Streptococcus, Lactobacillus, and Propionibacterium.   The lactic acid bacteria breaks down the lactose (milk sugar) into lactic acid. Then in the last stage of production, the Propionii bacteria consumes the lacti acid which results in the signature holes in Swiss Cheese.  

Sour Cream Chocolate Bundt Cake: 
Sour cream is produced using lactic acid bacteria.  Again, the lactic acid bacteria breaks down the sugars in cream and sours and thickens the cream.  

We all had a good time enjoying all the tasty flavors of foods containing bacteria, yeast, and mold! Microorganisms often have a negative association with foods due to constantly occurring outbreaks of Listeria monocytogenes, E.coli, or Salmonella.  But we should also appreciate all the helpful bacteria that produce the complex flavors of other foods that we often enjoy.