Most cheese recipes require you to use starter cultures to convert milk lactose into lactic acid. Although you can trust the product to work its magic, there is no obvious way to determine this activity in the fluid.
It doesn’t make sense to start making cheese if the cultures are improperly working. That means you need the supplies and equipment to track the acidity levels in the milk.
You’re going to want an acid testing kit, an acid meter, and sodium hydroxide available for your home cheesemaking supplies to measure this trait.
How Does an Acid Testing Kit Help?
An acid testing kit allows you to measure the acidity of milk or whey. Increasing levels are essential to the cheesemaking process, so having an all-in-one product that takes these readings is helpful when monitoring your recipe.
If you purchase an acid testing kit for home cheesemaking, it should contain a syringe, graduated column, and enough sodium hydroxide solution to obtain an accurate reading.
How Does an Acid Meter Help?
An acid meter is a better choice for home cheesemakers when the goal is to make multiple batches. You’ll receive burettes to take titration readings with an adequate product.
If you take your cheesemaking seriously, you’ll eventually want to use this product. A simple testing kit works well for the first trial runs to see if you like this fun hobby and lifestyle.
How Do I Test Acidity Levels?
Fill the glass reservoir in your testing kit with the sodium hydroxide solution before filing the graduating column by applying pressure to the rubber pump on the acid meter. You’ll notice the product reaches zero, with any excess returning to the reservoir.
Measure 9ml of milk or whey for testing. Pour the fluid into a beaker or test tube included with your kit. It works best if you hold it against a white surface.
Add five drops of phenolphthalein from your kit to the milk or whey, stirring gently until mixed.
Next, open the tap to let the sodium hydroxide run as droplets into the sample. Keep stirring to ensure an even mixture. You must continue until the pink coloration lasts for at least ten seconds.
Look at the column to see how much sodium hydroxide got used. Multiply this figure by .1, then over the decimal one place to the left to get your acidity level.
If your sodium hydroxide usage is 2.3ml, that means your titratable acidity is .23%.
Match the figures to what the recipe suggests is an ideal percentage. If that information is not available, a rising acidity level is enough information to tell you that your cultures are working appropriately.