Introduction: Cultivating Streptococcus Lactis for Multi-Uses.
Lactococcus lactis is a Gram-positive bacteria used extensively in the production of buttermilk and cheese. L. lactis are cocci that group in pairs and short chains, and depending on growth conditions appears ovoid with typically 0.5 - 1.5 �m in length. L. lactis do not produce spores (non-sporulating) and are not motile (non-motile). Cultured in the laboratory, L. lactis colonies appear bright orange on nutrient agar. They have a homo-fermentative metabolism and have been reported to produce exclusively L(+) lactic acid. However, reported that D(-) lactic acid can be produced when cultured at low pH. The capability to produce lactic acid is one of the reasons why Lactococcus lactis is one of the most important micro-organisms involved in the dairy industry.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Obtaining Mesophilic Culture.
So, we are going to make a mesophilic culture, which means cultivating the Streptococcus Lactis at about 30 C or 86 F for the yanks.
Where do we obtain our raw Gram-positive bacteria you ask? Well, we go where S.L. poops and spits; Cultured Buttermilk, a dive bar where all the bacterium of the Lactis likes to hang. Make sure your cultured buttermilk from your local grocery store has live cultures and hasn't been euthanized via pasteurization. We need live specimen.
Step 2: JAR the SUCKERS in a Warm Spot.
So, you take your carton home and poor two cups worth into a mason jar. This is where things get wild. You leave it out in a warm place. It doesn't have to be exactly 86 F, but it helps the lil' buggers mingle like they are high on ecstacy, and that is what we want.
24hrs later and the lactic acid bacteria should have increased acidity, the by-product naturally produced by S.L. while fermenting lactose, the primary sugar found in milk. As lactic acid is produced by the bacteria, the pH of the milk decreases and casein, the primary protein in milk, precipitates causing the curdling or clabbering of milk. This process makes buttermilk thicker than plain milk.
Step 3: Cryogenics
So, now we have some yogurt-like substance that tastes more sour and smells delicious. Time to fill up the ice trays and freeze those little guys in their frenzied state.
Once you freeze the bugger, you can use the ice cubes to infect regular milk any time. People say to use one ice cube worth, but I always use two because there is so much. Put the ice cubes of RIPENED buttermilk in the freezer.
So, the deal is, 1 cube per 2 cups of regular milk. (Use two cubes if you make a lot.) Repeat the 24hr process in a warm place and the infection has spread. Each cube will be 1 oz of Mesophilic starter culture!
Put it in the fridge when it is the consistency of yogurt. I keep two cups of ripened buttermilk in my fridge at all times.
Step 4: The Next Step. What Is This Stuff Good For? PANCAKES for 1.
The most ridiculous of pancakes.
1 cup (350ml) buttermilk
3 Tablespoons (50g) melted butter - use microwave
1 Tablespoon (15ml) Vanilla
1 cup (125g) white flour
3 Tbsp (40g) sugar
1/2 tsp (3g) baking soda (make sure it's not 3 years old... ;-)
1/2 tsp (2g) baking powder
1/2 tsp (4g) salt
Mix wets and then mix with drys. That simple.
Step 5: Best Pizza Crust Ever for 2.
Best PIZZA DOUGH EVER
The flavor of this dough is faintly cheesy and the texture softer than most doughs. If you like a less chewy crust, you will enjoy this one.
4 to 5 cups all-purpose flour
1 1/2 cups buttermilk (ripened)
1/2 cup (1/4 pound) butter
3 tablespoons light brown sugar
1 teaspoon salt
1/2 teaspoon baking powder
1/2 cup water
1 tablespoon vegetable oil
2 packages dry yeast
Put the butter and the buttermilk in a saucepan and place it over a low flame. Warm the milk slowly so the butter melts in it. Do not let the milk get hot. Stir the yeast and sugar into 1/2 cup of warm water. Let stand for 5 minutes.
Combine the Drys and then combine the Wets and mix.
Form into a ball and then paint some vegetable oil on the ball. Put it back in your metal bowl and cover with a towel and stick in a warm place.
Let the yeast do it's business.
This makes two thin crust pizzas 15 inches in circumference.
Step 6: Da Cheese for 3. : GOUDA
GOUDA CHEESE - You can use the culture to acidify milk for other cheeses as well.
I N G R E D I E N T S
1 Gallon Fresh Milk - I just use vitamin D, but u can actually use any of the other milks.
4 oz. Mesophilic Starter Culture
1/4 tab Rennet --I use 1 tab, because, well, 1/4 just doesn't work timely enough.
I N S T R U C T I O N S
Warm the milk to 85 F (29.5 C).
Add 4 oz of mesophilic starter culture and mix thoroughly with a whisk, the culture must be uniform throughout the milk.
Dissolve 1/4 tab rennet into 3-4 tablespoons COOL water. Hot water will DESTROY the rennet enzymes.
Slowly pour the rennet into the milk stirring constantly with a whisk.
Stir for at least 5 minutes.
Allow the milk to set for 1-2 hours until a firm curd is set and a clean break can be obtained when the curd is cut.
With a long knife, cut the curds into 1/2 inch cubes.
Allow the curds to sit for 10 minutes to firm up.
Slowly raise the temperature of the milk to 102 F (39 C). It should take as long as 45 minutes to reach this temperature. During this time, gently stir the curds every few minutes so they dont mat together.
Once the curds reach 102 F (39 C), allow the curds to settle, then carefully remove 3 cups of whey from the top surface.
Replace the lost whey with 3 cups of 102 F (39 C) water.
Cook the curds at 102 F (39 C) for another 45 minutes. Every 15 minutes remove 3 cups of whey and replace with 102 F (39 C) water.
At the end of the process, you will have removed whey three times.
Drain the whey by pouring through a cheesecloth lined colander.
Carefully place the drained curds into your cheesecloth lined mold.
Press the cheese at about 20 lbs. (9 kg) for 45 minutes.
Remove the cheese from the press and flip it.
Press the cheese at about 40 lbs. (18 kg) for 3 hours.
Remove the cheese from the press, careful it is still very soft.
Float the cheese in a COLD brine solution** for 3 hours. Be certain to flip the cheese over every 45 minutes or so to ensure even rind development.
Pat dry the cheese, you will notice the outer surface has begun to harden.
Place the cheese in your refrigerator to age for 25 days. You will need to flip the cheese over every day or it will dry unevenly.
If too thick a rind begins to develop, place an overturned bowl on top of the cheese, or place it in a covered container. However, continue to turn the cheese daily and do not wrap it in plastic.
Inspect daily for mold. Should mold develop on the cheese surface, simply remove it using a paper towel dipped in white vinegar.
At the end of 25 days you can age it further by waxing it or you may use it immediately.
If you wax the cheese, continue to flip the cheese every 3 days or so.
** BRINE SOLUTION
Dissolve 1.5 cups of salt into one quart warm water.
Cool the brine in your freezer, some salt will precipitate out.
To use the solution, simply place it in a bowl and place your cheese into it.
After you are done with the brine, you can store it in a container in your freezer.
With each new cheese, you will need to add additional salt so that the solution is saturated.
The solution is saturated with salt when no additional salt can be dissolved no matter how long
Step 7: Oh, Boy, the Ranch Dressing for 4. Totally Forgot.
3/4 cup mayo
3/4 cup buttermilk
1/2 tsp parsley flakes
1/2 tsp onion salt
dash garlic salt
Mix and shake. That easy.