Buttermilk Starter FAQ

Thinking of making cultured buttermilk at home? We're excited to help you get started! As with any new project, we understand that you might have questions - so we've collected the most frequently asked questions from our customers to guide you on this next culturing adventure. If you're already maintaining a buttermilk culture, be sure to review our Cultured Buttermilk TroubleshootingFAQ for tips and tricks for keeping your starter culture healthy.

Still haven't found what you're looking for? Don't forget to consult our full collection of expert advice on making cultured buttermilk at home or reach out with any questions. We're here to help!



Q. What types of buttermilk starter cultures do you carry?

A. We carry an heirloom (reusable) Cultured Buttermilk Starter. Our Sour Cream Starter is a direct-set (single use) starter, which includes optional buttermilk instructions. 


Q. Are the buttermilk starters mesophilic or thermophilic?

A. Both the Heirloom Buttermilk Starter Culture and the Sour Cream Starter Culture are mesophilic cultures, meaning they culture at room temperature, 70º-77ºF.


Q. What is the difference between the direct-set and the heirloom starter cultures?

A. Direct-set starter buttermilk culture is a single-use culture; one packet makes one batch of buttermilk or sour cream. Heirloom buttermilk starter culture is reusable indefinitely, with care. Heirloom buttermilk must be recultured at least every 7 days.


Q.  What ingredients and bacteria strains are in your buttermilk starter?

A. Our buttermilk starter culture is heirloom, so that means the strains may evolve and change a bit over time. This means that we're unable to keep an accurate list of the bacterial strains. However, we get all of our cultures tested for safety before they're sold.

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Q. How long will the buttermilk starter culture last if unopened? What do I do with extra packets of buttermilk starter culture?

A. Extra packets of buttermilk starter culture may be stored in the refrigerator or freezer. Information on how long each type of culture lasts may be found on each product page.


Q.  Do I need to buy buttermilk starter each time I make buttermilk?

A.  The direct-set Sour Cream Starter Culture (which can be used to make buttermilk) is a one-time use culture. One packet makes one batch of buttermilk or sour cream, and 8 packets are included in one box.

The heirloom Cultured Buttermilk Starter is a reusable culture. With proper care, the culture can be perpetuated from batch to batch. Reserve a small amount of buttermilk from a previous batch to make a new batch once per week.


Q. What kind of milk can I use?

A. Any type of pasteurized dairy milk can be used with direct-set and heirloom starters. Raw milk can be used, but when working with heirloom cultures, there are special requirements for making raw milk buttermilk.


Q. Can I use raw milk to activate your heirloom buttermilk starter culture?

A. Our heirloom buttermilk starter is in a freeze-dried state. To safely activate, we recommend using pasteurized milk (not ultra-pasteurized). To use raw milk, please follow instructions for Making Raw Milk Buttermilk.


Q. Can I use raw milk with your direct-set buttermilk starters?

 A. Yes, raw milk may be used with the direct-set cultures.


Q. Can I use goat milk to activate an heirloom or direct-set buttermilk starter culture?

A. Yes, as long as it is pasteurized. If using raw goat milk, follow instructions for Making Raw Milk Buttermilk. Note that goat milk yields a thinner consistency product.


Q.  Can I use non-homogenized milk to make buttermilk?

A.  Yes. Non-homogenized milk makes wonderful buttermilk. The only difference when making buttermilk with non-homogenized milk is that the cream will rise to the top of the buttermilk just like it does with the milk, so the top layer of the buttermilk will be more yellow in color.


Q.  Can I use low-fat milk to make buttermilk?

A.  Yes, you can, just keep in mind that buttermilk made with low fat milk will have a thinner consistency than buttermilk made with whole milk.


Q. Why can’t I use ultra-pasteurized/UHT milk for culturing buttermilk?

A. Milk that is “too clean,” such as ultra-pasteurized/UHT milk, or milk that has been heated by microwave, may be too sterile for the buttermilk culture to use as nourishment.


Q. Why must heirloom cultures be recultured at least every 7 days?

A. In order to maintain culturing viability, to be able to use the culture indefinitely, you must make a new batch at least every 7 days.


Q. Why can’t I reculture a direct-set starter?

A. Direct-set starters are one-time-use cultures. It may be possible to use a portion from the previous batch made with a direct-set starter to make a new batch of buttermilk or sour cream, but after a few batches, the culture will weaken and a new dose of direct-set starter is needed.


Q.Will my buttermilk culture better or have more probiotics if I use more than one packet? Can I use more starter culture to achieve a thicker consistency?

A. Do not use more starter than recommended. Using too much starter can crowd the bacteria, causing the bacteria to run out of food before the buttermilk completely ferments the milk. The result is often a thinner, sometimes bitter, buttermilk.


Q. Can I combine different buttermilk starter cultures or add a probiotic capsule to increase the probiotic content?

A. Buttermilk cultures are a carefully balanced combination of bacteria. Mixing different bacteria together may cause the culture to weaken or die.


Q. Once I’ve activated the buttermilk starter culture and used it to make a batch of buttermilk, what should I do with what’s left?

A. What you have remaining is buttermilk. Use it as you normally would.


Q.  Where can I view the instructions for using your buttermilk starter culture?

A.  The instructions for each buttermilk starter are included in the box.  Instructions may also be found on our website:  Heirloom Buttermilk Starter instructions and Direct-Set Buttermilk and Sour Cream Starter Instructions.



Q. How important is temperature when culturing buttermilk?

A. The temperature for culturing buttermilk can vary from 70º-77ºF, but it is very important to stay within that range. Too warm and the bacteria will die. Too cool and the culturing will halt, and will likely not start again.


Q. How will I know when my buttermilk has set?

A. Buttermilk that has set will be more or less uniform in appearance: one solid mass. The buttermilk should appear relatively smooth and should pull away slightly from the side of the container when tipped. Sometimes a bit of whey will separate from the buttermilk during the culturing process. This is completely normal.


Q. I see that I can make sour cream with the direct-set starter. Can I also make sour cream using the heirloom buttermilk starter?

Rather than the starter, you can use the cultured buttermilk from the heirloom starter.  Detailed instructions can be found in our article How to Make Sour Cream.


Q.  Can I use buttermilk to create cultured butter?

A.  Yes.  Detailed instructions can be found in our article How to Make Cultured Butter.


Q.  If I’m making other cultured foods (yogurt, sourdough, kombucha, etc.), how far apart do I need to keep the buttermilk culture?

A.  When items are being actively cultured in open containers, we suggest keeping a distance of at least several feet between items. When your cultured items are being stored in the refrigerator with tight-fitting lids, there is no need to keep distance between them.


Q. How do I put my heirloom buttermilk starter on hold while I am on vacation?

A. If you will be gone longer than a week, the best solution is to find a friend who can care for your buttermilk culture. There are other options for Taking a Break from Making Buttermilk that may be less reliable but still have shown a fair amount of success.


Q. Can I switch back and forth between raw milk and pasteurized milk for making buttermilk? Can I switch back and forth between cow milk and goat milk? How about between low-fat milk and whole milk?

A. Yes, you can switch between milks for each batch of buttermilk. Remember, if you are using raw milk with an heirloom (reusable) culture, you will need to maintain a pasteurized mother culture in order to preserve the viability of the culture.


Q. My house is colder than 70ºF, how can I culture a buttermilk?

A. Many homes maintain temperatures that are cooler, especially in the winter. In our article, Cold Weather Care for Starter Cultures, find out how to keep your cultures the perfect culturing temperature.


Q. Are there differences when culturing buttermilk at high altitudes?

A. Making buttermilk at high altitudes causes it to set faster. With that said, you may want to avoid putting buttermilk into culture overnight.


Q. How long will finished buttermilk last in my refrigerator?

A. In the refrigerator (40° to 45°F): 7 days for heirloom variety to maintain culturing viability; 2 weeks for edibility.