The ability to achieve reproducible, excellent quality mozzarella is one I am unsure exists with the home cheese maker. I am yet to hear of someone who has had recurring success with this cheese. Here, I smirk upon the term ‘home cheese maker’ as someone who does not have access to a pH meter. With this rather negative view, I embark upon the journey of Chapter 3 in Mary Karlin’s book. My own results were subpar, about a 5/10.
As a Scientist, the most exciting aspect of Mozzarella making for me was discovering the science of the casein network that holds significant importance to the development of melt and stretch in a cheese. While many, if not most, cheeses are expected to melt under heat, the properties behind a stretch and melt combination is one that possesses a sort of Goldilocks zone in terms of balance.
It’s all about the right pH. pH is a measure of the acidity of a substance. A pH of 7.0 (water at 25C) is considered neutral whereas pH < 7.0 is acidic. To get a cheese that has good stretch and melt, the casein network in the curds need to have the right amount of casein-casein interaction. A high pH curd (6.5ish) will possess too many casein interactions coupled with the presence of another nuisance: calcium phosphate. A very low pH curd (below 4.6) will disconnect the network. The right pH is between 4.9 and 5.2 and I am quite sure that even within this range, the results will vary quite a bit.
Quick mozzarella is one where a precise amount of vinegar or citric acid is added to milk in order to create the right pH environment. However, traditional mozzarella is made through the action of cultures on milk to reduce its pH. It is a slower process (about 16 hours long) but can be expected to give far more tasty results! Yum, yum.
Last weekend, Valerie, Ian and I made a version of quick mozzarella from Mary K’s book – Junket Mozzarella. While we didn’t have junket tablets with us, the conversion is (thank you, Ian) 4 tablets = 1/4 tsp of (double strength) rennet.
The process of curd formation is one that is very standard. In this case, the addition of vinegar is with the purpose of creating the right acidity in milk and is not to be confused with milk coagulation by vinegar in direct acid cheeses (like in paneer, ricotta etc.). To coagulate milk with direct acid, the temperature needs to be roughly 180-190F. In this case, rennet coagulated the milk at 90F. We let the curds set for 30 minutes, till it gave a good clean break.
The second stage of mozzarella making involves heating the whey to 180-190F and adding
slices of the mildly shaped curds. Then, kneading and stretching them into an eventual ball. This is the hardest part, in my opinion, in the process of mozzarella making. Note that you have to immerse your hands in HOT whey so be prepared for that (or buy heat-proof gloves). My results were subpar mainly because I think I overstretched my curd, thus dissociating some of the casein network.
Once the balls are formed, immediately drop them in ice cold water to stop further expansion. I got various shapes of mozzarella and I’m hoping that next time I do it, I get two decent sized balls.
- Appearance: white and rubbery feel
- Nose (aroma): fresh, dairy like with little (or no) tangy odor
- Overall Taste: FRESH
- Sweet to Salty: sweet
- Mouthfeel: gummy and a bit squeaky, when melted tastes pretty good.
Okay – so how does this cheese do under the influence of temperature and strain? That is the ultimate test of its melting and stretching properties.
This cheese melted reasonably well when placed in a toaster oven for a few minutes. Would have liked more melt, but then again I was hungry and took it out too soon 😀
When stretched, this cheese seemed to do pretty well. The inner ‘layers’ of cheese seem to be stretching better than the surface layer.
Perhaps more heat was required or this was just the result of inferior mozzarella.
The image on the right shows finer details of the stretch. Stringy casein connections can be seen and the hope was for this to be more widespread throughout the cheese.
I do plan to make this cheese again and will try the traditional method. It will require more time investment and hence greater risk, what with the low success rate and all. However, I am humbled by my own limitations and want to master the ability to make really good mozzarella in future!