Making mozzarella and ricotta at home is possible and you don't need any special equipment except for a brewer or cheese maker thermometer. The basic recipe comes from my bookSavour (page 12-13), it is quite detailed, so here I will do a quick step by step explanation, with a little trick to cut down time.
Start with 2 litres of full cream not homogenised milk, if it looks too fat take away some of the cream at the top. Gently heat the milk to 38°C (110.4°F).
Add 4 heaps tbsp of live yogurt, in New Zealand I only use Cyclops Yogurt (thick and creamy type) to make cheese. I tried with a variety of yogurts, but this really seems to have the right bacterias kicking into curd action! Stir.
Usually I only add yogurt, and then the waiting time after cutting the curd is about 4 hours. if you want speedy results add a little citric acid too. I am not sure how many cheese makers would do this, on the other hand I am not sure how many cheese makers would actually use yogurt for bacterias!
If you wish to use citric acid add it now, for a 2 litres of milk I added about half a tsp.
After stirring the yogurt (and citric acid, if using) cover with a lid and keep the temperature at 38°C, wait 10 minutes and then add the rennet. I use vegetarian rennet, 1ml of it mixed to 1 ml of cold water.
Stir for one minute, check that the temperature is still 38°C, then cover with a lid and then let it rest for 45 minutes. During this time the temperature shouldn't drop, but if it is a very cold day it would pay to have your pot inside a bigger pot with hot water.
After 45 minutes the curd will be set.
Cut the curd into 4-5 cm squares, cover and wait 15 minutes. This is the first cut.
After 15 minutes cut the curd a second time to 1cm pieces using a slotted spoon. If you didn't use the citric acid try bring the temperature to 35°C, then cover and rest the curd rest for 4 hours. During this time the temperature must be always kept at 35°C, so check often. If you used the citric acid bring the temperature up to 41°C and stir gently with the slotted spoon until the curd pieces look like a soft jelly (about 5 minutes). I am still not confident with the citric acid method but it was very successful during our Slow Food Waitekere mozzarella event, and Alli has the recipe here, so I guess that I mixed and matched a little with the two methods.
To check if the curd is ready drop a bit in hot water at 90°C, if it stretch it is ready to be rolled! I use a sieve to keep the curd in place, and the thermometer not to burn my fingers.
If the curd is not stretchy yet, wait 15 more minutes and try again, and again, and again... (if you follow the method of not adding citric acid. I guess that this is why so many people cannot be bother to make it, since you may have to wait a long time!).
Prepare a pot of water at 90°C, and one of cold water. Collect the curd into a colander or sieve and add a pinch of salt. Cover with the hot water (or lower the colander or sieve into the hot water), stir with the thermometer or a wooden spoon. I always forget to use rubber gloves, but here they would be a good idea: you need to pick up a piece and stretch it, and the water is hoooot!.
At this stage I had a surprise visit from Gwen, so I stopped everything to make us a cup of coffee (and maybe left the mozzarella in the hot water more that I had to), but on the other hand it was a good thing because I didn't consider the fact that with two hands occupied I couldn't have taken pctures. I gave Gwen my iPhone, she wasn't sure of when to click but she did a pretty good job, I think!
Stretch and stretch, working with big batches you just need to stretch and cut the end off, but with such a little batch unless you are making bocconcini instead of cutting the ends off you can just roll your mozzarella strip into a ball.
Don't roll it too tight or it will be hard, keep it really loose (I like soft mozzarella best),
and then drop it into the bowl with cold water. With 2 litres of milk I made 3 medium mozzarella and a little one. If you can, eat your homemade mozzarella on the same day :-).
Now with the whey you can make ricotta. Bring it back to 90°C, a froth will appear on top.
Turn the heat of and wait 5 minutes for the froth to set, then collect it with a slotted spoon,
and place it in a sieve lined with fine gauze, arranged on a container to collect the excess liquid.
I used to stop here and make very little ricotta indeed, and then I decided that patience was the best trick. So I just left the kitchen as it was, and covered the pot. Every 20 minutes or so I went back to the pot and collect the (now very fine) foam with a tea strainer (a slotted spoon is good only for the very first ricotta foam, the rest was too fine).
I did this all afternoon, I didn't need to heat the whey again, just leaving the pot to rest with the lid on was enough, and the ricotta kept coming up to the surface. I collected more that I ever expected.
By the evening I had a small ricotta, and the texture was very creamy. I think that I could have collected a little more but I got tired and needed the stove for cooking dinner, still, if next time I will use more than 2 litres of milk I could get enough ricotta for 4 portions (this one my daughter ate for dessert, and we all just had a tiny taste). We also ate the mozzarella for dinner, but I forgot to take a photo, sorry!
If you are interested in more homemade cheeses here is Halloumi (and ricotta again, this is my most popular post), and here is Labne.
Recipes by Alessandra Zecchini and Photos by Gwen Lenehan and Alessandra Zecchini ©