These are both pretty easy recipes, and the resulting cheeses are delicious! You can get citric acid and rennet from here:
citric acid
rennet
Whenever you are making cheese, you want to use stainless steel, glass, or enamel pots, no aluminum. also, make sure you keep everything very clean.
Mozzarella
Add 1 1/4 to 2 tsp of citric acid powder to milk and stir well
Dissolve 1/4 tsp of rennet in 1/4 c. cold unchlorinated water
Heat milk to 88 degrees
Add rennet, stirring in an up and down motion
Leave milk for about 5 minutes, until it reaches a clean break (you put
your finger in the milk, it "breaks away" and the depression fills with
whey)
Cut into 1/2 to 1 inch curds
Heat to 105 degrees, stirring gently to keep the curds from matting
Leave curds for about 5 minutes
drain curds, reserving whey
heat whey to 175 degrees (on stove)
Dip a ball of curds in the hot whey until they start to turn shiny. Knead
the curds until they are smooth and shiny, dipping them in the whey to reheat them if necessary. Salt the curds, form them into a ball, and
cool.
Refrigerate for up to several days in an enclosed container
The amount of citric acid varies, depending on how firm a cheese you want. The more citric acid, the softer the cheese. I use a slotted spoon to dip the curds in the hot whey, and rubber gloves to knead it.
Ricotta
Once you are done dipping the curds in the hot whey, heat the whey to
a slow boil. You will probably will have already noticed there are tiny
curds floating in the whey. As soon as it starts to boil, you should
notice it foaming. I let keep it at a slow boil for 5 minutes. Then I pour
it into 1/2 gallon glass jars, and let it sit in the fridge for 12-24 hours.
The cheese should have settled into the bottom of the jar. Pour off as
much of the whey as you can, then strain the rest through quad-folded
cheesecloth lining a strainer. I feed this whey to my chickens, there
isn't much left to it at this point. Once all the whey has strained out, I
make the cheesecloth into a pouch and hang it suspended in a jar with a
rubber band. Then in a few hours, once all the whey is out, I salt it and
put it in a jar in the fridge