Yogurt Starter FAQ

What ingredients are in your yogurt starters?  

Our viili, filmjölk, matsoni, piimä, Greek, and Bulgarian yogurt starters are grown in our own facility using locally sourced pasteurized organic whole milk and live active cultures. The direct-set dairy cultures contain milk and live active cultures. The Vegan Yogurt Starter contains rice maltodextrin (non-GMO) and live active bacteria.

What is the difference between different varieties of yogurt cultures?

The specific bacteria strains each have certain properties that will affect the finished yogurt. Some produce more lactic acid, making a more tart yogurt; some cause the milk proteins to coagulate in different configurations, making the finished yogurt gluier, or ropier, or more solid; some produce distinctive flavors, making the yogurt astringent, or cheesy.

Which bacteria strains do your yogurt starters contain?

  • Traditional Flavor Direct-set: Bifidobacterium lactis, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus

  • Mild Flavor Direct-Set: Bifidobacterium lactis, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus delbrueckii subsp. lactis, Streptococcus thermophilus

  • Viili: Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis biovar. diacetylactis, Leuconostoc mesenteroides subsp. cremoris

  • Filmjölk: Lactococcus lactis, Leuconostoc mesenteroides

  • Matsoni: Lactobacillus lactis subsp. cremoris, Acetobacter orientalis

  • Piimä: Streptococcus lactis var. bollandicus, Streptococcus taette

  • Greek: Lactobacillus bulgaricus, Streptococcus thermophilus

  • Bulgarian: Lactobacillus bulgaricus, Streptococcus thermophilus

  • Vegan Direct-set: Bifidobacterium bifidum, Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Streptococcus thermophilus

  • Kosher Traditional: Bifidobacterium lactis, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus

  • Kosher Mild: Bifidobacterium lactis, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus delbrueckii subsp. lactis, Streptococcus thermophilus

What is a direct-set yogurt starter and how is it different from a reusable yogurt starter?

Direct-set yogurt starters are one-time-use cultures. The powdered starter is added to milk and allowed to incubate producing yogurt. It may be possible to use some yogurt made with a direct-set starter to make a new batch of yogurt, but after a few batches, a new dose of direct-set starter is needed. With yogurt made from a reusable (heirloom) yogurt starter, a small amount of each batch is used to make the next batch. With proper care, a reusable yogurt starter can be perpetuated indefinitely. Reusable cultures should be cared for and perpetuated at least once a week to maintain their ability to culture milk.

Which starter is best for goat milk?

Any of our starters will work equally well for cow milk, goat milk, or any other dairy milk, and with raw milk or pasteurized milk.

If I want a thicker yogurt, can I use more starter?

Do not use more starter than recommended. If you use too much starter, the bacteria can become crowded, and may run out of food before the yogurt completes setting up. The result is a thinner yogurt, not a thicker one!

Can I mix starters together or add a probiotic capsule to get a different kind of yogurt?

Yogurt cultures are a carefully balanced combination of bacteria that will produce a particular kind of yogurt. If you mix different cultures or bacteria together, the bacteria may compete and weaken or die.

Once I start using the starter culture, how long will the bacteria stay viable enough for re-culturing?

We recommend that you use the yogurt from an heirloom culture within 5 to 7 days for re-culturing, to ensure the bacteria are strong enough to reproduce. You may be able to re-culture a yogurt from a direct-set starter a few times, but each batch will become thinner than the last, until you need a new direct-set starter.

How long will the starter culture stay good in the package?

Our freeze-dried cultures are shelf-stable for at least a month at room temperature, but we recommend refrigerating them if you are not going to use them right away, to extend their viability. Unopened, the culture is stable for 9 to 12 months in the refrigerator, and at least 12 months in the freezer. 

If I’m going on vacation, how can I preserve my yogurt starter?

If you are using a reusable variety of yogurt starter, ideally you should make a new batch of yogurt every 7 days. Occasionally you may be able to stretch that period out by another day or two. If you will be gone longer than a week, the best solution is to find a friend who can care for your yogurt culture. You can also try freezing a small amount of yogurt in ice cube trays to thaw later and use as starter yogurt. Freezing is not a perfect solution but it will usually work as long as the yogurt is only frozen for a short period of time (no more than a few weeks).

Making Yogurt

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

Yes, you can use any sort of milk for each batch of yogurt. Don’t forget, if you are using raw milk with an heirloom (reusable) culture, you will need to maintain a mother culture made with sterilized or pasteurized milk to preserve the viability of the culture.

Can I add cream to the milk to make a thicker yogurt?

The more milk fat (cream) there is in the milk, the thicker the yogurt will be. However, if you use whole cream, the bacteria may not remain viable enough to re-use for a second batch, since the culture uses milk sugar (lactose) for food. Whole cream has very little lactose. Adding half-and-half or cream to whole milk would result in a very rich, thick yogurt.

Can I make yogurt with lactose-free milk?

Lactose-free milk is usually made from cow milk with lactase added. Lactase is the enzyme missing in the gut of lactose-intolerant individuals. It breaks the lactose down into two simple sugars: glucose and galactose. The yogurt culture also consumes the lactose, and uses it to produce lactic acid, which makes the milk proteins coagulate. So if the milk did not have any lactose to start with, the yogurt culture would not work well. (The bacteria might consume the glucose for partial success in culturing.)

However, since the lactose is broken down in the culturing process, there is not much lactose left in the finished yogurt even when you use regular milk. As a result, many lactose-intolerant individuals can enjoy yogurt. You might want to try a small amount of good quality plain yogurt, and if all goes well, start making your own. If you have concerns about your ability to tolerate yogurt, you should consult with your health-care practitioner.

How long does it take for a mesophilic culture to set up?

The amount of time it takes for a mesophilic (room-temperature) culture to set up properly depends on many things: The type of milk, how fresh the milk is, the temperature of the room, the freshness of the culture, the humidity of the environment, etc. A brand-new starter culture can set up as quickly as 10 hours, or it may take 48 hours. After you’ve made the starter culture, the subsequent batches can take anywhere from 10 to 24 hours.

How long does it take for a thermophilic culture to set up?

Ordinarily a thermophilic (heat-set) culture will take around 5 to 7 hours to set up, assuming it is culturing at a steady temperature of about 110°F. If the temperature is a little warmer or a little cooler, the time could vary.

How many batches of yogurt can I make with each packet of yogurt starter?

With a direct-set starter, you can generally make around eight 1- to 2-quart batches of yogurt per packet, or up to 10gallons if you make larger batches each time. Using proper care with our reusable yogurt starters, you can make an unlimited amount of yogurt by taking a small amount from each batch of yogurt to make the next batch. 

What’s up with the quantities of direct-set starter? The instructions say a box can make either 8 quarts or 20 gallons.

There are eight packets of direct-set yogurt in a box, and with those you can make eight small batches of yogurt, or two very large batches, or anything in between. You must have one packet of starter for it to work properly in a quantity of milk, and you must have enough milk for the starter to grow and flourish.

The proportions of starter to milk that will successfully make yogurt are as follows:

1 packet: cultures 1 to 2 quarts at one time
2 packets: cultures 2 to 8 quarts at one time
4 packets: cultures 8 to 40 quarts at one time

How important is it to keep the right temperature for the yogurt as it’s culturing?

The temperature for yogurt can vary within a certain range, but it’s very important to stay within that range. Too warm, and the bacteria will die. Too cool, and the culturing will halt, and probably not start again. For a mesophilic culture, the range is 70° to 78°F, with about 72° to 76°F being ideal. For a thermophilic culture, the range is 105° to 115°F, with 110° to 112°F being ideal.

How will I know when my yogurt has set?

Yogurt that has set will be more or less uniform in appearance: one solid mass. There should not be a clear separation of curds and whey (white solid portion on top and clear liquid on the bottom). The yogurt should appear more or less smooth, not lumpy. If you gently tip the container, the yogurt should pull away from the side of the container. Sometimes a bit of whey will separate from the yogurt during the culturing process.

If I strain my yogurt, how long is the whey good for? What can I do with it?

Refrigerated, your whey should stay good for up to six months. You can use it to ferment vegetables like cabbage. The purpose of the whey is to get the lacto-fermentation to start up a little faster, For instance, most recipes for sauerkraut recommend about 4 tablespoons of whey to a quart of cabbage. You can also add whey to smoothies for extra protein, either as liquid, or frozen in ice cubes.

Yogurt Troubleshooting

I followed all the instructions exactly, and my yogurt did not turn out. What did I do wrong?

We get this question a lot! There are three possibilities: either you misunderstood a step or two in the instructions, or the milk was not culturable, or the starter you received was not working properly in the first place. Be sure to rule out the first two possibilities before assuming the last. Our customer support representatives can help you figure it out. The most common errors are:

The culturing temperature was not right. You can test the temperature of the environment you’re culturing in, whether it’s a yogurt maker or a countertop, by preparing some water the same way you would prepare the milk for the yogurt, and taking the temperature of the water at intervals throughout the culturing time.

You used the wrong quantity of milk, or the wrong quantity of culture. The activation batch (mother culture) is 1-2 cups for mesophilic yogurt starters and 1 quart for thermophilic yogurt starters. It is important to let the culture come back to operating strength in this small amount of milk before trying to culture a larger batch. Also, you must use at least 1 packet of culture, as a smaller amount may not have enough strength to work. Do not use too much culture for the amount of milk. A culture that is crowded can’t work properly, and can weaken or die before it finishes setting up the yogurt.

You just didn’t wait long enough. A new yogurt culture can take longer than you expect to set up properly. Be sure to allow enough time for the culture to fully awaken and start working.

The milk was not culturable. Milk that is not “clean” enough can present competition for the yogurt culture. This would include raw milk that is more than a few days old, or that was not chilled immediately after milking. It can also include pasteurized milk that is not very fresh and has not been properly heated. On the other hand, milk that is “too clean,” such as ultra-pasteurized milk, or milk that has been heated by microwave, may be too sterile for the yogurt culture to use as nourishment.

Why did my yogurt separate into curds and whey?

Separation is generally a sign that the yogurt has cultured too quickly or too long. It may indicate that the culture has died. Try mixing the curds and whey together, then make a new batch, being careful to control the time and temperature. If that fails to produce a good yogurt, then the culture has died and you will need to replace it.

Where can I find more troubleshooting information?

Click here for Yogurt-Making Troubleshooting FAQs.






Homemade Yogurt

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<td><span style="font-family: verdana,geneva; font-size: small;">&nbsp;</span> <br />
<p><span style="font-family: verdana,geneva; font-size: small;">Originally a simple fermented dairy product, yogurt now has many variations and personalities. It can be thin and runny, or thick and firm. It can be made from cow milk, goat milk, sheep milk, nut milk, soy milk, rice milk, and from numerous other creamy substances. In some countries the milk of buffalo, horses, yaks, or camels is used.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">For most of this discussion, we&rsquo;ll refer to yogurt in its original form: a fermented dairy milk. This was how yogurt was first developed, and most of the yogurt in the world is made this way.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">Essentially yogurt is the product of beneficial bacteria fermenting milk and turning it into a thickened, acidic food that will stay fresh longer than milk itself, and that contains millions of bacteria that are welcomed by the human gut.</span></p>
<h1><br /><strong><span style="font-family: verdana,geneva; font-size: small;">The History of Yogurt</span></strong></h1>
<p><span style="font-family: verdana,geneva; font-size: small;">The word yogurt comes from a Turkish word meaning to curdle or to thicken. Today it is spelled yogurt, yoghurt, or yogourt, with yogurt being the most common American spelling.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">It&rsquo;s probable that the earliest yogurt was made by accident in Mesopotamia around 5,000 BC, when milk-producing animals were first domesticated. The milk was likely stored and transported in bags made from the stomachs of these animals, and the digestive juices and bacteria in the stomach linings made the milk coagulate and become acidic. Not only was it a new and interesting food, but the acidity and helped to keep it edible for longer</span> <span style="font-family: verdana,geneva; font-size: small;">than if it had just sat out in a bowl or jar.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">There is also some evidence of yogurt being used as a cleaning product and a beauty lotion as early as 2000 BC. The acidity of the yogurt helps clean away dirt and rust, and also helps clear away dead skin and nourish healthy skin cells.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">Yogurt was a popular food in the Middle East for thousands of years, and has been a staple of the Eastern European diet. It&rsquo;s now eaten throughout the world, as a main course, a snack, an ingredient in many recipes, and a condiment. It has gained considerable popularity in America in the last forty or fifty years, in keeping with general trends toward organic, cultured, and nutrient-dense foods.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">Yogurt can be mildly tart or quite sour, and can be thick enough to stand up on a plate, or thin enough to pour, or anywhere in between. It contains protein and calcium as well as a variety of vitamins. Additionally, the process of yogurt fermentation is very similar to the process of digestion, so it can be easily consumed.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">Many people eat yogurt plain, while others prefer to mix it with fruits or vegetables, or to add flavors or sweeteners. It is used in a variety of recipes as a flavor enhancer or leavening, and frequently enjoyed as a refreshing drink.</span></p>
<h1><br /><strong><span style="font-family: verdana,geneva; font-size: small;">Nutritional Content</span></strong></h1>
<p><span style="font-family: verdana,geneva; font-size: small;">Not only does yogurt contain the same amount of protein and fat as the milk from which it is made, it also contains calcium, riboflavin, vitamin B6, and vitamin B12. While numerous claims have been made regarding the health benefits and digestibility of yogurt, we don&rsquo;t comment on medical, health, or nutritional qualities of our products. However, a great deal of research on the subject is readily available on the Internet and in dozens of books.</span></p>
<h1><br /><strong><span style="font-family: verdana,geneva; font-size: small;">How is Yogurt Made?</span></strong></h1>
<p><strong><span style="font-family: verdana,geneva; font-size: small;">&nbsp;</span></strong><span style="font-family: verdana,geneva; font-size: small;">True yogurt is made from animal milk. Theoretically, the milk of any mammal could be used to make yogurt.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">With care, yogurt cultures can also be used to ferment and coagulate non-dairy &ldquo;milks&rdquo; such as the creamy liquid obtained from nuts, rice, soy, or coconut. While these products are technically not really yogurt, they can be used and enjoyed just like dairy yogurt, alone or in recipes.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">Put very simply, the process of turning milk into yogurt involves fermentation. Certain types of bacteria act on the lactose (milk sugar) that is in milk, and produce lactic acid. The lactic acid lowers the pH of the milk, and causes the milk protein to coagulate and make a firm mass. The acidified milk is an inhospitable environment for destructive bacteria, so the yogurt stays fresh longer than untreated milk.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">The bacteria that does this is called beneficial bacteria, because it supports digestion and is nourishing, as opposed to pathogenic (harmful) bacteria that causes disease. The beneficial bacteria is called probiotic. It&nbsp; is similar or identical to the type of bacteria that lives in the human gut and which is responsible for the process of food absorption. When you use live cultures, the probiotics stay in the yogurt, and the yogurt can then be used as a starter to make more yogurt.</span></p>
<h1><br /><strong><span style="font-family: verdana,geneva; font-size: small;">Yogurt and Other Fermented Dairy Products</span></strong></h1>
<p><span style="font-family: verdana,geneva; font-size: small;">There are many different ways that beneficial bacteria can be introduced to milk and make an entirely new food. The main difference between the different fermented dairy products is the bacteria used to make them, resulting in different flavors and consistencies.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;"><em>Yogurt</em> can be cultured with a variety of different bacteria combinations, each of which gives the yogurt a characteristic taste and consistency. There are typically somewhere between the range of two to six different bacteria strains in yogurt, and they are similar to the bacteria found in the intestines.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;"><em>Kefir</em> is a thickened milk made from little clumps of yeast, bacteria, and milk proteins that ferment the milk. There are about thirty different bacteria strains present in kefir grains. It has a slightly sour flavor and sometimes a faint effervescence. Koumiss is a similar product, made from mare&rsquo;s milk.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;"><em>Buttermilk</em> is the name given to the whey that&rsquo;s left over when butter is made, but it more commonly refers to a milk drink made by adding bacteria to low-fat milk, producing a thickened product with a tangy flavor.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;"><em>Sour cream</em> is cream or high-fat milk that&rsquo;s been cultured and thickened. It&rsquo;s very slightly sour, and usually quite thick. It was originally made by letting fresh cream thicken naturally as a result of fermentation from the bacteria present in the cream. When cream is pasteurized and has no natural bacteria present, it must be fermented with added bacteria.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;"><em>Cr&egrave;me fraiche</em> is a European-style sour cream, slightly sweeter than what we are used to in America. It&rsquo;s also made by letting raw cream thicken naturally, or by adding buttermilk cultures to cream. Cr&egrave;me fraiche can be heated without curdling, unlike sour cream.</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;">In recipes, you can often substitute one cultured milk product for another and get similar results. In fact, sometimes it is hard to tell the difference between a thin, tart yogurt and a thick, sour kefir or a creamy buttermilk!</span><br /><br /><span style="font-family: verdana,geneva; font-size: small;"><em>Soft and hard cheeses</em> are also made by culturing milk over a longer period of time. Some cheeses can be easily made by straining the moisture out of yogurt or sour cream, while others require additional fermentation and culturing steps.</span></p>
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