Thursday, 20 October 2011

Since my last post we have made a few different cheeses all made with fresh, raw cows milk from stichelton dairy. Firstly we made a couple of different lactic cheeses, both with the same starter culture but only one with rennet so that comparisons could be made. Once coagulated we cut the curd and hung them up in a muslin bag to drain overnight. The next morning we salted the lactic cheese and tasted them straight away! There was an interesting comparison between the two, the one with rennet taking on more lemony notes and having a firmer consistency where as the one without rennet was quite acidic.

We also made a Cheddar which will be hopefully ready in time for our graduation ceremony next year!
We started by adding a freeze dried starter to the milk at 32˚C to acidify the milk, turning the lactose into lactic acid. After about 40 minutes the traditional animal rennet was added and then stirred for 5-10 minutes and left to coagulate. Once you could slide your finger underneath the now 'jelly like' curd and lift it to reveal a clean break in the curd it was ready to cut (This takes about an hour). We cut the curd into small 'cube like' pieces and raised the temperature of the vat to 40˚C to scald the curds which are constantly stirred for around an hour. The scalding of the curd allows it to form a thin skin and firm up as not to realise too much moisture, otherwise you will end up with a dry cheese. We then proceeded to drain the whey leaving us with the curds in the bottom of the vat. All this time we were checking the level of acidity in the whey making sure that the culture we added to the milk was doing its job. The test you use to do this is called a titrateable acidity test which involves adding a few drops of phenolphthalein solution to 10ml of whey and then sodium hydroxide is dripped into the whey until they react and the whey solution turns pale pink, holing for around 15 seconds. The amount of sodium hydroxide you have added to the whey solution will give you a measure of the lactic acid in your curds.

The curds are piled up and left to form together, they are then cut into bricks and turned, all the time keeping them close to one another as not to let them get to cold so that the culture may get drowsy and slow down the rate of acidification. Once the bricks of curd have been turned and the whey tested several times their consistency has changed from 'spongy' to 'chicken fillet like'. The curd should now be at the acidity level you want it to be, in this case about 4.5%.
The curds have now turned from bricks into knitted slabs and are ready to be put through a mill where 2% of dry salt is added and mixed with the curds. The curds are now ready to be put into the cloth lined moulds and are pressed overnight.
The next day we removed the cheese from the moulds, larded and clothbound them. They will then be matured at around 12-13˚C in about 90% humidity and fingers crossed they will taste great in around ten months time!

No comments:

Post a Comment