Fine fibers created by hand stretching for Asadero type cheese at Ochoa Cheese, Oregon
If your Quick Mozzarella doesn’t always turn out perfectly, despite many recipe’s suggesting that it is “so easy”, stop blaming yourself! Stretched curd cheeses, often referred to by their Italian name of “pasta filata”, depend upon some pretty precise chemistry occurring in order to turn out well. In this article I have extracted a bit of what I cover in an entire chapter in my book “Mastering Artisan Cheesemaking” on the subject of stretched curd cheeses. I have included three recipes, from Quick to Long.
The Chemistry of Stretching
Before curd can stretch there must be specific changes in the protein structure. For those changes to occur, the curd must reach the magic pH level of about 5.2. Through the development of acid, calcium is removed from the protein structures, allowing for the formation of the right kind of protein network for stretching. (You can read more about how calcium and other minerals interact with acid in chapters 1 and 3 of my book.) To successfully make these cheeses, you need to be able to monitor the development of acid. A pH meter is the easiest method, but I’ll be telling you how to perform a stretch test on your curd that will tell you the same thing (this is the way they did it in “the old days”).
Stretched curd cheeses are heated in hot whey or a water before they are stretched. In addition to getting the curd to the right temperature at which the protein structure can begin to elongate and move, this high-heat treatment essentially (but not by legal definition) pasteurizes these cheeses. Any culture remaining will be killed as well—one more reason it is important to be sure to have the proper acid development before you try to stretch the curd. Some of the coagulant used will be deactivated, too, causing changes in the breakdown of protein during aging. But the enzymes remaining from the starter culture should provide plenty of protein breakdown power if you are making an aged version of this type of cheese.
Let’s go over the two main approaches to making these cheeses – the quick, added acid method and the long, traditional method. You can also combine the two, as Christy Harris has done in the recipe she provided for my book. If you are making a variety that you want to age, go for the traditional approach!
Why Quick Recipes aren’t always Simple
Quick, easy recipes for mozzarella rely upon the addition of a food acid, almost always citric acid, at the right level to lower the milk pH to the magic 5.2 range. If the milk starts out at a different pH than usual, though, and your measurements are not precise (frankly measuring with a teaspoon is never that exact) then you may end up with a pH above or below the needed level. Too low or too high and the curd won’t stretch. Because the acid is added when the milk is still a liquid, you can’t perform the old fashion stretch test that I am going to tell you about in a bit to determine if the acid level is perfect, but you can use pH strips or a pH meter. Still, these recipes works more often than not and you can increase your odds of success by weighing the calcium chloride and then keeping a good record of the results.
While many quick mozzarella recipes call for using a microwave to heat the curd, skip this approach and use the whey. It is just as easy, in my opinion, and less messy, more accurate, and better for the curd. Microwave ovens rarely, if ever, heat the curd evenly. Even heating is quite important to the process.
You can make quick mozzarella with any type of milk- cow, goat, or sheep. Pasteurized is fine, but not ultra-pasteurized (as many of the proteins have been damaged and will not allow the curd to form and/or stretch). Quick mozzarella cannot be aged, since there are no starter bacteria cultures to protect and enhance the cheese during aging. So plan on using it quickly (perhaps that is what the name actually refers to!) If held in the fridge for a few days, even easy recipes will take on lovely melting qualities for pizza cheese. If you want to keep it soft and tender, you can store it in a bit of whey in the fridge. If the cheese becomes too soft or mushy when stored this way, add a bit of salt and calcium chloride to the whey next time. (more on that at the end of this post)
Traditional Pasta Filata Methods
A beautiful skein made by Ochoa Cheese
Mozzarella, Provolone, Caciocavallo, and Queso Oaxaca are just a few of the cheeses made using the pasta filata techniques. Very few commercially available versions are still made by hand, but you can find a few stalwart artisans carrying on these traditions today. If you have made traditional cheddar cheese, prepare to be surprised at how similar the process is, except for the stretching. It is believed that the Britons learned the many of the processes of cheddar making by watching the Roman invaders make mozzarella type cheeses.
Traditional pasta filata cheeses develop the right amount of acid after a long ripening period, partially in the whey and partially after the curd is drained and kept warm. When the goal pH nears (or you think it is almost ready) a stretch test should be done. A piece of curd is heated in hot whey or water and tested for its ability to stretch. After heating the chunk, fold it in on itself a few times, observing the texture. If it folds easily, heat it again and fold again. Then heat a third time and try pulling the piece away from itself. If ready, it will stretch into a long, thin strand. At this point the rest of the curd can be stretch or cooled and frozen for future shaping. (In some parts of the country you can buy curd ready to stretch).
Some recipes use Mesophilic cultures, others Thermophilic and still others a combination of bacteria. Old world recipes often use raw milk and rennet paste (producing a sharp, piquant flavor). Lipase can be added to help emulate this more complex flavor profile.
When using the whey from making traditional and hybrid mozzarella, it is a good idea to first heat the whey until the proteins left in the whey precipitate out of the liquid, usually at about 185F. Skim these delicious real ricotta curds off of the top with a sieve and drain. Then let the whey cool to 175-180 for stretching the curd.
Hand stretching is extremely physical and requires deftness and care, here cheesemakers at Ochoa Cheese work the curd like pros.
When the curd is ready to stretch, it is a good idea to cut it into small chunks before heating, as this will help heat it evenly. I suggest using a small strainer basket or sieve to lower the curd into the hot whey. When beginning to work the curd, use gentle folding motions, bending the sides in towards the back of the mass (if you have ever made a loaf of bread, the motions are almost identical). At any time when the curd becomes too cool to move easily, reheat it! When the mass is shiny, usually after a couple of rounds of folding and heating, then it is ready to shape. If you are making “string” cheese or a skein (as with queso Oaxaca or queso asedero) then put the curd through several stretching sessions to continually elongate and align the protein networks. When the final shape has been attained, cool the cheese in water. Salt can be added to the heating water and/or the cooling water.
Stretched Curd Cheese Recipes
Quick and Simple Mozzarella
- 1 gallon milk
- 1 ½ tsp citric acid dissolved in ¼ cup cool water
- ¼ tsp calcium chloride dissolved in ¼ cup cool water
- 1/8 tsp double strength rennet dissolved in ¼ cup cool, non-chlorinated water
- Combine milk, citric acid solution, and calcium chloride solution.
- Warm milk to 90 F, stirring evenly.
- Remove from heat and stir in rennet solution with an up and down motion. Still the milk, cover and let set for 5 minutes until curd is well gelled.
- Cut the curd into ½ inch pieces let set for 2 minutes.
- Stir and heat the curd to 105 F over 5-10 minutes or until curd starts to feel somewhat “plastic” or gooey.
- Place a colander over a pot and pour curds into it, reserving the whey. Cover curds.
- Heat whey to 175-180F.
- Cut up curd mass into 1 inch chunks then lower them in 1-2 cup amounts into hot whey.
- Stretch, following stretching tips earlier.
Hybrid Method Mozzarella
- 1 gallon milk
- 1/16 tsp TA 60, 1/16 tsp MM OR 1/8 tsp MA 4000
- ¼ tsp calcium chloride diluted in 1/8 cup water (optional)
- ¼ – ½ tsp citric acid dissolved in 1/8 cup water
- 1/8 tsp double strength rennet diluted in 1/8 cup water
- 1. Warm ½ gallon of the milk to 96F
- 2. Add cultures, let set for 5 minutes then stir well for 3-5 minutes
- 3. Add calcium chloride solution (optional)
- 4. Maintain at 96 F and ripen for one hour, goal pH is about 6.2
- 5. Combine citric acid mixture with the other ½ gallon of milk and warm to 96F, goal pH about 6.0
- 6. Combine two milk mixtures, goal pH about 6.1
- 7. Verify temperature is 96F and add rennet solution stirring with an up and down motion for about 15-30 seconds
- 8. Still the milk and let set for 30 minutes or until ready to cut
- 9. Cut into 3/8 inch chunks, rest 5 minutes
- 10. Gently stir and heat to 115F over 30 minutes.
- 11. Turn off heat and let settle for 5 minutes
- 12. Pour off the whey (saving) and pour curds into cloth lined colander. Set over the drained whey, cover, and keep curds at 102F, turning mass every 30 minutes, until curd passes the stretch test (described earlier).
- 13. Heat whey to 180F and follow stretching directions
Traditional Style for Aging
- 2 gallons milk
- 1/8 plus teaspoon Thermo B
- ½ tsp calcium chloride diluted in 1/8 cup cool water (optional)
- 1/16 teaspoon double strength rennet diluted in 1/8 cup cool water
- Warm milk to 80F and sprinkle cultures on top. Let set 5 minutes. Stir well.
- Increase temperature to 90F and hold for one hour.
- Stir in calcium chloride if using.
- Stir in rennet solution with an up and down motion for one minute. Still milk and let set quietly until clean break is achieved. Goal coagulation time is 45 minutes.
- Cut curd into 3/8 – ½ inch chunks, rest 5 minutes
- Stir gently and heat slowly to 95-98F over 15 minutes. Then stir and heat to 118F over 30 more minutes. Hold at 118F, stirring occasionally to keep from matting, until curd pH is 6.0. This may take 60-90 minutes.
- Drain the curds (saving whey) in a colander. Cover colander and place over warm pot, keeping the curd temperature at about 102-104 F.
- Turn curd mass every 30-45 minutes until curd pH is about 5.2 or when curd passes stretch test.
- Heat whey to 180F, add a pinch of salt and follow stretching directions. Curd can also be chilled and saved to stretch later (it can also be frozen).
Quick versions of mozzarella can be stored in the refrigerator for a few days, but will not age safely. They are best used fresh! The traditional method can be used fresh, stored in a light brine made from whey, smoked, and aged. The hybrid method can also be aged, but will likely be a little less complex do to less bacterial activity.
Storing in whey/brine:
- Mix one quart of filtered (through cloth) whey left over after stretching with an 1/8 teaspoon of salt. This amount can be adjusted depending upon if you salted the whey during stretching or the water during chilling. The saltier they mixture, the more firm the cheese will be, so if you want it tender, you may want to omit the salt completely.
- Immerse small balls or discs of fresh mozzarella in the solution. A ziplock type bag can be used – squeeze the extra air out of the bag so that moisture surrounds the balls. This method requires less liquid.
- If the liquid becomes cloudy or the cheese starts getting soggy or soft, you probably need to add a bit of calcium chloride to the brine. Try about ¼ teaspoon per quart. Adjust up if the cheese continues to soften and less if the cheese becomes too firm.