This article is about an Aroma or flavouring type culture called Lipase that is frequently added to milk in cheese making.
Lipase (pronounced lie-paze) is a naturally occurring water soluble enzyme that performs essential roles in the digestion, transport and processing of dietary lipids (e.g. triglycerides, fats, oils) in most, if not all, living organisms (i.e. plant and animal). Raw milk (i.e. whether it’s cow, goat, or sheep’s milk) has over 60 different enzymes including Lipase, the amounts of each being dependant on animal and it’s diet.
The flavour of all cheeses comes mainly from enzyme activity during aging and not from the flavour of the enzyme itself or from starter culture lactic acid producing bacteria. In milk, some enzymes make it through pasteurization, but many are deactivated or damaged, including Lipase. To compensate for the deactivation Lipase is commonly added in cheese making when using pasteurized milk to breakdown of milk fat (called lipolysis) and develop stronger more piquant flavoured cheeses such as brine preserved Feta type cheeses and most Italian type cheeses.
Lipases’ benefits are: flavour enrichment, a better scent (more persistent and characteristic), and a reduction of the ripening time.
Lipase from an animal should be exactly the same thing as Lipase from a plant. The problem is that plants produce very small quantities, so it’s not practical to extract it. Therefore most Lipases are derived from kid-goats, lambs, and/or calves sources. The component that animal lipase is made from is generally proprietary, but sources in literature say drying and grinding of pre-gastric glands at the base of the calves tongues.
Common Lipase types and their use in cheese making are:
- Calf (Cow), creates a delicate and mild “piquant” flavour, which is well perceptible and has a pleasant butter scent, lightly spicy.
- Kid (Goat), creates a string sharp “piquant” flavour typical of Provolone, a well perceivable and persistent scent, lightly spicy.
- Lamb (Sheep), creates a strong and marked traditional flavour typical of Pecorino Romano, a well perceptible in the mouth with a good persistence flavour, medium spicy.
- Microbial (Fungal), primarily if want more vegetarian cheese.
Note: Mixtures such as Kid & Lamb are often available.
Lipase should always be added to the milk before the milk has started to coagulate:
- Before adding acid in fresh direct acid coagualted cheeses.
- Before significant acidification in lactic acid coagulated cheeses.
- Before adding rennet in rennet coagulated cheeses.
To maximize dilution and avoid pockets of high Lipase activity, Lipase should be:
- A fine grind size (normal with manufactured commercial Lipase).
- Pre-dissolved in cool water, amount of water being dependant on amount of Lipase being used.
- Thoroughly mixed with the milk.
Lipase dosage rates vary based on:
- The initial strength of the product and the age and storage history of your product.
- Fat content of the milk, the curdling temperature, the milk pH and the temperature of the cheese in the presses.
- Whether the cheese maker wants a sweet, medium, or strong flavour.
A common starting dosage (vary up or down depending on taste results) is:
- 1.25 ml per 8-12 liters milk.
- 1/4 teaspoon per 2 US gallons.
For maximum longevity, Lipase should be stored:
- Away from light.
- In an air tight container.
- Is heat sensitive and while tolerates warmer temperature for up to a month while shipping, should be stored at colder temperature, thus in freezer is common.
Some commercial manufacturers of Lipase are:
Unless making your own, manufactured commercial Lipase is a specialty product and normally only available from cheese making supply stores.