What should I do with the extra yogurt starter?
Extra yogurt starter should be sealed up (a ziplock-style bag works well) and stored in a cool dry place such as a freezer.
How important is temperature when making yogurt?
Temperature is very important for the proper development of the yogurt bacteria. At the proper temperature, the yogurt bacteria will consume the lactose in the milk, multiply quickly, and make yogurt. If the temperature is too cold, a race develops between the yogurt bacteria, which are slowed down due to the cooler temperature, and the milk bacteria, which are multiplying quickly due to a warmer (than the refrigerator) temperature. If the milk bacteria win, they will kill the yogurt bacteria. Even if the yogurt bacteria prevail, the fight with the milk bacteria can damage the culture making long-term use problematic.
For our direct-set cultures and our Greek and Bulgarian starters, the ideal culturing temperature is 110°F.
For our Viili, Matsoni, Filmjolk, Piima, and Buttermilk starters, the proper culturing temperature is 70-78°F.
How do I know what temperature my yogurt maker operates at?
Yogurt making appliances can be used with direct-set Yogurt Starters as well as our Greek and Bulgarian yogurt starters. It's a good idea to test the temperature of your yogurt maker before using it to make yogurt. (Sometimes they malfunction.) To test your yogurt maker, fill the interior container with water (the same quantity you would use of milk to make yogurt) and then operate the yogurt maker per the manufacturer's instructions. Test the water with a thermometer after an hour and then again after 3 or 4 hours. The temperature should stay between 105°F and 112°F.
Do not use a yogurt making appliance with the Viili, Filmjolk, Matsoni or Piima yogurt starters as it will keep them too warm and kill the yogurt culture.
I want to use my crock pot to make yogurt. Is there anything I need to know?
Slow cookers (aka crock pots) can be a great way to culture Direct-set, Greek, or Bulgarian yogurts but the main concern is ensuring they are not too warm for the culture. Use the method above for testing a yogurt-making machine to determine if your crock pot can maintain the proper temperature.
Do not use a slow cooker with the Viili, Filmjolk, Matsoni, or Piima yogurt starters as it will keep them too warm and kill the yogurt culture.
How will I know when my yogurt has set?
Yogurt that has set should be more or less uniform in appearance: one solid mass. There should not be a clear separation of curds and whey (white solid portion for the top half and clear liquid on the bottom half). The yogurt should appear more or less smooth (before being stirred), not lumpy. If you gently tip the container, the yogurt may pull away in a mass from the side of the container (like you would expect jello to do). Please note, sometimes a bit of whey will separate from the yogurt during the culturing process. If clear liquid (whey) is present on top of the yogurt or even a bit on the sides, this is just a normal variation. If the yogurt has fully separated into curds and whey, that is a sign of a problem (see below).
My first batch of yogurt (using the freeze-dried starter) has been culturing for a number of hours but is still the consistency of milk. What should I do?
Greek and Bulgarian Yogurt Starters: Generally speaking, the first batch (from the dried starter) can take anywhere from 5-12 hours to set properly. The length of time is due to the hibernated state the yogurt is in as a powdered starter. Subsequent batches will generally set much more quickly. We do recommend checking your yogurt every 30-60 minutes after about six hours so the process can be stopped as soon as the yogurt is set. Be sure to double- check the temperature at which the yogurt is culturing. The most common culprit for long-culturing yogurt is too low a temperature (under 110°F). If your yogurt is staying at 110°F consistently, just give it a bit longer. Up to 12 hours is fine.
Viili, Matsoni, Filmjolk, and Piima Yogurt Starters: The amount of time necessary for our counter-top yogurt starters to culture is very dependent on room temperature. These starters do require a room temperature of no less than 68°F with 70-78°F being preferred. (Be sure to take into account possible temperature fluctuations at night and whether the culture could possibly be in a draft, affected by an air conditioning unit, etc.) Generally speaking, the first batch (from the dried culture) will take anywhere from 12-48 hours to set with 48 hours being far more common during colder months of the year than 24 hours. Occasionally it can even take a bit longer than 48 hours. As long as the mixture is still the consistency of milk or thicker (and has not separated into curds and whey), you can continue to let it culture past 48 hours for up to 60 hours until it appears to be fully set.
My yogurt didn't set properly. It separated into two layers: solid on top and liquid underneath (curds and whey). What should I do?
Separation is generally a sign that the yogurt has overcultured, and the culture may have died. There are several factors that can cause this problem. The most common is exposure to heat. If culturing yogurt is exposed to a temperature higher than the proper range (80°F for mesophilic cultures; 110°F for thermophilic cultures), the yogurt starter is likely to die. Contamination is also a potential issue. In particular a bit of soap or food residue the dishwasher may have missed can be harmful to the culture.
What to do: Discard the separated batch. Start over using using the backup packet of starter culture.
If for some reason this second attempt produces the same curds and whey result, please contact us. With a live culture, we find that in about 1% of cases, a starter culture will fail for an unknown reason. We suspect in many of these cases the culture may have been exposed to a source of high heat during transit but ultimately we will never know. We are happy to immediately replace the culture.
My yogurt seems to have set but there's a little clear liquid floating on the top and the sides. Is this okay?
Yes, some separation of whey from the yogurt is fine and is a natural variation within the culturing process. Sometimes it happens, sometimes it doesn't. A full separation where the top half the jar is a white mass and the bottom half is clear liquid is a problem, however (see above).
When can I flavor my yogurt?
Yogurt can be flavored and sweetened after the 6-hour refrigeration period. Please be sure to reserve some yogurt for making the next batch prior to flavoring or sweetening. (If using raw milk and a pure starter, keep the pure starter unflavored.)
How do I make the yogurt thicker?
There are generally three ways to improve the thickness of the yogurt:
- Increase the fat content. By using whole milk or a mixture of milk and cream, fat content is increased which naturally increases the thickness to the yogurt.
- Strain the finished yogurt using cheesecloth. Using cheesecloth over a bowl or jar allows whey to drain from the yogurt resulting in thicker yogurt. Allow the yogurt to drain for as little as 30 minutes but up to several hours until the desired consistency is achieved. (For ideas on how to use the resulting whey, click here.) Please note, individuals living at higher altitudes may need to adjust the technique a bit to ensure the whey drains in an efficient manner.
- Use a yogurt cheese maker to strain the yogurt. As an alternative to using cheese cloth, commercially available yogurt cheese makers allow you to strain some of the whey from the yogurt resulting in thicker yogurt.
- Heat the milk and hold the temperature. Heating the milk to 180°F and holding the temperature for 30 minutes prior to letting the milk cool to 110°F can also increase the thickness of the final yogurt.
- Add dry milk powder to the yogurt. 1/2 cup dry milk powder can generally be added to several quarts of milk prior to the milk being heated.