By Dr. Carla Cashin ND & Hayley Stobbs RNCP
Yogurt is a fermented dairy product that is created by adding beneficial bacterial cultures to warm milk. With temperature control and time the milk sugar, lactose, serves as a source of food for the introduced beneficial bacteria, which transform lactose into tart tasting lactic acid. The final yogurt product is thick, tart, and tasty. Interestingly, the original name for yogurt, yoghurmak, means to thicken.
Those with lactose intolerance often find 24-hour homemade yogurt much easier to digest since it contains very little lactose. In contrast, most store bought yogurts are fermented for only 6-8 hours, and do not allow enough time for most of the lactose to be digested by the bacterial culture.
The longer fermentation of 24 hours not only leads to a low lactose product, but also allows for a product with large quantities of probiotics, beneficial bacteria. It is estimated that 1/2 cup of yogurt contains around 350 billion CFU, several times greater than most over the counter probiotic supplements. That means it is best to try small amounts of the yogurt first before eating a large serving.
Start with 1-2 Tbsp the first day, 2-4 Tbsp the second day, and ½ - 1 cup the third day, and from there on 1-2 cups as desired. You may notice mild gas and bloating when first adjusting to the fermented food. If you get pronounced digestive disturbance, discontinue the product as you may have prepared it incorrectly, are sensitive to even small amounts of lactose, or are unable to tolerate large amounts of probiotics. Speak with a healthcare practitioner if this occurs.
Preparation Time: 20 minutes
Fermentation Time: 24 hours
Makes about 1 litre (4 cups)
1 thermometer (should read to as low as 100F)
1 freestanding oven thermometer
1 medium pot
1 clean dish towel
Oven or yogurt maker
¼ cup store-bought yogurt (Recommend Brand: Tree Island plain yogurt)
1 litre whole or 2% organic milk
1 litre sterilized glass mason jar, or 2, pint glass mason jars
1 small measuring cup
Turn oven light on to bring oven temperature up to 100-110F (double check with a free-standing thermometer placed in the oven). The oven at this temperature will act as an incubator for yogurt making. If you are using a yogurt maker instead, turn it on.
Pour 1 litre of milk into a clean medium sized pot, and bring to 180F temperature on medium heat. To prevent burning of milk, whisk milk while heating. Bringing the milk to a temperature of 180F will re-pasteurize the milk, killing off any unwanted bacteria.
Once the milk has gently boiled at this temperature for 1 minute, take pot of milk off heat source and let cool to 100F. Place a clean dish towel over the yogurt while it is cooling. You can place the pot in a cold water bath (sink filled with cold water) for a few minutes to speed up the process.
Once the milk has reached a temperature of 100F, whisk ¼ cup of yogurt into the milk. This step introduces the beneficial bacteria which allows the transformation of milk into yogurt to occur.
Replace dish towel with aluminum foil over pot, and place into 100F oven or transfer to a yogurt maker.
The yogurt will remain within its incubator (oven or yogurt maker) for 24 hours.
After 24 hours, check on your yogurt. The milk should have thickened into a beautiful yogurt that smells slightly sweet and tangy. At this time your yogurt is complete and you can transfer to clean mason jars and place in the refrigerator for up to 2 weeks.
If your oven temperature is on the low side, consider a longer fermentation of 29 hours to ensure a low lactose product.
An alternative to the method above is to use a small insulated cooler as the incubator. Pre-heat the insulated cooler by filling it with hot water to reach a target temperature of 110F. Proceed with steps 2 - 7 as outlined above.
Fallon, Sally Ph.D. “Nourishing Traditions,” New Trends Publishing Washington, D.C:, 1999.
Gottschall, Elaine. “Breaking the Vicious Cycle,” The Kirkton Press Baltimore, Ontario 1986.
Katz, Sandor Ellix. “The Art of Fermentation,” Chelsea Green Publishing. White River Junction, VT, 2012.
Prasad, Raman. “Recipes for the Specific Carbohydrate Diet,” Fair Winds Press Beverly, Massachusetts:, 2008.