Cheese Making Basics

Cheese Making at Home  Many people brew beer and wine at home, but few people make cheese  Cheese is dehydrated, salted, spoiled milk  The spoilage is carefully controlled using beneficial bacteria and mold cultures  Expensive equipment such as this custom-built cheese press is not necessary for home cheese making, but it makes the process much less labor intensive  Cheese ingredients cost about $6 per pound of cheese (cost is dominated by good quality milk) Creamy Havarti Cheese Ready for Brining

Sanitation  All countertops, pans, tools and hands must be washed and sterilized before touching the milk  Sterilization prevents harmful bacteria, yeast, and molds from contaminating the milk and cheese  ¼ cup of bleach is added to hot water to make a sterilization bath

Custom Cheese Vat  An electric food warmer is filled with enough water to form a water jacket around a six gallon steam pan  The steam pan holds enough milk to make a block of cheese weighing about 5 to 5½ lb  Milk temperature control is crucial for cheese making  The food warmer was modified to add a thermal sensor  A computer regulates and records the vat’s water jacket temperature over time

Temperature Record  The computer records the water jacket temperature throughout the cheese making process  It takes about 8 hours from raw milk to cooked cheese curds  The main advantage of using the computer is the ability to concentrate on the milk, curds and whey, not worrying about manually adjusting the temperature for 8 hours

Pasteurization  Store milk is quickly pasteurized at a very high temperature to destroy harmful bacteria – but…  High temperature destroys milk for cheese making  To make good cheese, we must buy fresh raw milk and pasteurize it ourselves  By Texas law, raw (unpasteurized) milk can only be sold by the farmer directly to the consumer at the farm  The FDA minimum requirement for milk pasteurization is 145 degrees for 30 minutes  I buy raw milk directly from a dairy farmer and slowly pasteurize it at 150 degrees for at least 30 minutes using the cheese vat

Pasteurization – Cool Down  Milk must be quickly cooled after pasteurization to prevent harmful bacteria from growing  Cold tap water is flushed through the water jacket for about 30 minutes to cool the milk quickly  Stirring the milk occasionally and adding ice cubes to the water jacket quickens the process  The milk is cooled until it reaches the ideal bacterial inoculation temperature (70 to 100 degrees depending on the type of cheese being made)

Inoculation with Good Bacteria  Mold cultures, orange food color, or flavoring may also be added at this time  After a 5 minute rehydration time, the bacteria are stirred into the milk  Powdered lactic acid bacteria are added to the milk once it has cooled to the proper temperature  For Swiss-style cheeses such as Emmental and Jarlsberg, gas-producing bacteria are also added

Acidity – Measuring pH  The lactic acid bacteria convert milk sugar (lactose) into lactic acid  The texture of cheese (meltability, hardness, etc.) is highly dependent on how much lactic acid is produced during the cheese making process  A handheld pH meter is very useful in monitoring acid development  pH 7.0 is neutral, less than 7.0 is acidic, more than 7.0 is alkaline  Fresh raw milk has a pH of about 6.6 (slightly acidic) before it is further acidified by the bacteria

Rennet – Setting the Milk  After a period of bacterial growth (30 minutes to several hours), the milk is gelled or “set” using an enzyme called rennet  The milk begins to gel a few minutes after rennet solution is stirred into it  The first sign of gelling is called “flocculation”  Flocculation can be detected using a plastic cup floating on the milk  Flocculation has begun when the cup stops moving easily  Flocculation time is used to determine when to cut the gelled milk into curds  Hard cheeses such as parmesan and cheddar are cut at 2.5 x the flocculation time, soft cheeses such as brie are cut at 4 x to 6 x

Cutting the Curd  The curds and whey are then heated slowly to a “cook” temperature ( degrees F depending on cheese type)  The curds continue to expel whey as they gradually harden  The gelled milk is cut into curds using a knife or wire whisk  Yellow liquid, called “whey”, begins to seep out of the curds soon after they are cut

Washing the Curd  The curds can be washed by draining a portion of the whey and replacing it with warm water  Water leaches out part of the lactose from the curds  Less lactose means less lactic acid (sharpness) in the final aged cheese  Washed curd cheeses were developed in northern Europe, notably Denmark & Holland  Gouda, Havarti, Edam, Jarlsberg, Colby, and Jack are examples of washed curd cheeses  They are typically milder and less crumbly than non-washed curd cheeses

Draining and Salting the Curd  The pH of the whey can be measured at this point, but it typically has not dropped yet  The pH of the whey inside the curds drops faster than the whey that has been expelled  The curds are drained and may also be salted prior to being put into shaping forms  Salt slows down the lactic acid bacterial activity so that the cheese will acidify gradually

Forming the Cheese  Now that curds have been separated from the milk, it is time to form them into a wheel of cheese  Curds are transferred into a mould such as a hoop or square box, lined with cheesecloth or large coffee filters (which are much cheaper than cheesecloth!)  The curds are allowed to drain for an hour or so before pressing begins

Pressing Process  Cheese must be periodically rewrapped and flipped over to maximize whey extraction  Pressing continues until the whey stops draining and the curds form a solid block of cheese  Cheese curds must be pressed for many hours to form them into a solid block of cheese  Cheese is pressed lightly at first, then with more force until most of the whey has been expelled

Cheese Presses  I use a custom-built pneumatic (compressed air) cheese press that operates with a flip of a switch  It gives me an accurate, adjustable pressing force up to 150 pounds to make harder cheeses such as cheddar and parmesan  The press can be as simple as a set of weights stacked on top of the mould  Commercially available cranked-spring presses are inaccurate, cumbersome to use, and typically limited to 50 pounds of force

Pressing Complete – Testing pH  The lactic acid bacteria continue to convert lactose to lactic acid during the pressing process  For this batch of Havarti cheese, the pH of the final ounces of whey has dropped to 5.4 about 20 hours after the bacteria were first stirred into the milk  This level of acidity will give a nice tangy flavor, soft creamy texture and good meltability  Insufficient acid development results in cheese that won’t melt and squeaks against the teeth  Too much acid development can make cheese bitter and crumbly and makes it liquify into a sauce instead of melting

Brining  After the cheese has been pressed into a solid block, it is typically brined in a chilled salt water bath for a few hours to a day or more  Brine is a saturated salt water solution which may also contain a bit of vinegar and Calcium Chloride  Brining pulls more whey out of the cheese, making it harder  Brining also infuses more salt into the cheese, preventing the bacteria from over-acidifying the cheese

Aging  After cheese is brined it is slowly dried and aged in a cheese cave (pronounced “cahv”) for several weeks to several years  Most types of cheese are edible within a week, but are not fully developed until weeks or months later  The aging process must be carried out in a controlled environment with a relative humidity of about 85% and a temperature that may range from 45 degrees to 70 degrees depending on the type of cheese  Household refrigerators are much too dry for aging cheese  Wine storage fridges are ideal because they are designed to keep corks humidified

Aging the Havarti  Since Havarti is a soft cheese, it will tend to flatten out  Therefore the cheese must be flipped every 12 hours or so for the first few days to even out the flattening process  Before brining, weight was 5 lb, 15 oz  After brining for 10 hours, the weight had dropped to 5 lb, 13 oz After Brining12 Hours1 Day2 Days 3 Days1 Week2 WeeksCut and Sealed

Questions?