Yogurt Starter FAQ

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

A. We carry direct-set and heirloom yogurt starter cultures. The heirloom starters are available in two types, mesophilic and thermophilic.


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

A. Direct-set yogurt starter cultures are single-use cultures: one packet makes one batch of yogurt. Heirloom yogurt starter cultures are reusable indefinitely, with care. Heirloom yogurts must be recultured at least every 7 days.


Q. What is the difference between mesophilic and thermophilic yogurt starter cultures? 

A. Mesophilic cultures at room temperature, 70º-77ºF. Thermophilic cultures at approximately 110ºF. 


Q. What yogurt starter cultures do you carry?

A. We carry the following starters:


Q. What is the difference between the different starter cultures? What is the flavor, texture, consistency? What types of bacteria are in each?

A. A comparison chart, listing each yogurt culture in detail, may be found here.


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

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


Q. What ingredients are in your yogurt starter cultures?

A. Ingredients for every culture we carry are found on each product page.


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, have special requirements. Alternative milks can be used, but will require thickeners in order to achieve a spoonable consistency.


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 yogurt starters are one-time-use cultures. It is possible to use some yogurt made with a direct-set starter to make a new batch of yogurt, but after a few batches, the culture will weaken and a new dose of direct-set starter is needed.


Q. Why can’t I reculture yogurt made with non-dairy milk?

A. Non-dairy milk is generally cultured using a direct-set starter. Please see previous question. Heirloom cultures consume lactose as their food source and cannot survive long term culturing alternative milk. A dairy mother culture must be maintained and used to culture the non-dairy milk. If you must be completely dairy free, the Vegan Yogurt Starter is your best choice.


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

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 yogurt completely ferments the milk. The result is often a thinner, sometimes bitter, yogurt.


Q. Can I combine different yogurt starter cultures or add a probiotic capsule to make a different kind of yogurt or increase the probiotic content?

A. Yogurt cultures are a carefully balanced combination of bacteria that will produce a particular type of yogurt. Mixing different cultures or bacteria together may cause the culture to weaken or die.


Q. Can I use raw milk to activate an heirloom yogurt starter culture?

A. Our yogurt starters are in a freeze-dried state. To safely activate them, we recommend using pasteurized milk (not ultra-pasteurized). To use raw milk, please follow instructions for Making Raw Milk Yogurt.


Q. Can I use goat milk to activate an heirloom yogurt starter culture?

A. Yes, as long as it is pasteurized. If using raw goat milk, follow instructions for Making Raw Milk Yogurt.


Q. Can I use non-dairy milk to activate an heirloom yogurt starter culture?

A. Non-dairy milk will not work to activate an heirloom starter. It must be activated using pasteurized dairy milk.


Q. Can I use raw milk, goat milk, or non-dairy milk with your direct-set yogurt starters?

A. Yes, raw, goat and non-dairy milk may be used with the direct-set cultures. If using raw milk, please follow instructions for Making Raw Milk Yogurt.


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

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 yogurt culture to use as nourishment.


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

A. What you have remaining is yogurt. Eat it plain, sweeten or flavor it and enjoy!



Q. Why do I have to heat pasteurized milk when using thermophilic cultures?

A. Heating the milk to 160ºF will kill any bacteria present in the milk that might compete with bacteria in the thermophilic cultures.


Q. How do I put my heirloom yogurt 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 yogurt culture. Another option is to freeze 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). Learn more here.


Q. 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?

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


Q. How do I know that my yogurt maker is operating at the correct temperature?

A. To test your yogurt maker, fill the interior container(s) with water (the same amount and temperature you would use with milk to make yogurt), then operate the yogurt maker per the manufacturer's instructions. Test the water with a thermometer after an hour and then again after 3-4 hours or so. The temperature should stay between 105°F and 112°F.


Q. I don’t have a yogurt maker, but I want to culture a thermophilic yogurt. What can I do?

A. There are a variety of methods for maintaining appropriate temperature for culturing thermophilic yogurt. Explanation of the different methods can be found in our article, How to Culture Yogurt Without a Yogurt Maker.


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

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. How do I make raw milk yogurt?

A. Please follow the instructions for the type of starter you are using.


Q. How can I make my yogurt thicker?

A. There are several ways to improve the thickness of the yogurt. Refer to the Flavoring and Thickening Yogurt article for information on a variety of thickening options.


Q. If I drain whey from my yogurt, how long can I store the whey in the refrigerator?

A. Whey will generally last about 6 months in the refrigerator. Always check the appearance and aroma. If it looks or smells bad, discard it.


Q. What do I do with whey?

A. Find lots of ideas in Ways to Use Whey.


Q. Can I make yogurt with lactose-free milk?

A. Maybe. Lactose-free milk isn’t actually lactose-free, but has lactase added, which makes the lactose easier to digest. Check the label and if you see lactase, the milk does contain lactose and may be used to culture yogurt. Avoid ultra-pasteurized milk for making yogurt.


Q. How importnat is  temperature when culturing yogurt?

A. The temperature for yogurt can vary within a certain range, 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 yogurt has set?

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


Q. Why is store-bought yogurt thicker than homemade yogurt?

A. Store-bought yogurt generally contains thickeners. You can drain whey or add thickeners to homemade yogurt to achieve similar thickness. Details are in our article, How to Thicken and Flavor Homemade Yogurt.


Q. When can I flavor my yogurt?

A. To avoid interfering with the culturing process, it is best to flavor after the culturing process is complete. This is most import when working with heirloom cultures. 


Q. Can I use my yogurt to revive another culture (like milk kefir, buttermilk, etc.)?

A. No, combining different cultures leads to competition between bacteria. The bacteria can kill each other, ending in an undesirable finished product.


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

A. Making yogurt at high altitudes causes it to set faster. Putting yogurt in to culture overnight might not be wise.


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

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







Yogurt with Raspberries

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Cotton Bag for Making Soft Cheese


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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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