Fermenting Foods
Fermenting foods is perhaps the oldest food preservation method and has grown in popularity in recent years due to their touted “gut”, probiotic, and other additional health benefits. Fermenting at home is an inexpensive way to control what goes inside your food. Many are finding emotional satisfaction from making their food at home and feel a connection to their ancestors by making things the way they did.
Fermentation is the process of “good” microorganisms fermenting sugars and nutrients in food to produce byproducts (acids) that usually preserve the food in some manner. For example, milk is fermented to produce acids that create cheese, yogurt, and other products. In most cases, fermentation alone cannot produce a shelf-stable (room temperature) food product. Nearly all fermented foods require canning to preserve or refrigeration. DIY blog posts have erupted all over the internet with varying methods that can lead to potential exposure to harmful pathogens due to a lack of proper pH, temperature, and time monitoring. Below are specific ways to control the fermentation process to ensure a safe, healthy, and delicious product (EUFIC, 2017; Gilliand, 1989).
Importance of Measuring pH Levels
The pH scale measures how acidic or basic a substance is and ranges from 0 to 14. A pH less than 7 is acidic and greater than 7 is basic. For fermentation to be successful at eliminating all potential pathogens the pH level must drop below an acidity of 4.6. Foods can NOT be guaranteed to be safe and free from harmful potential pathogens unless it is verified using a pH meter or test strip. Foods that “appear” to be safe can still contain harmful pathogens. This is very concerning for the novel and inexperienced home fermenter following DIY blog fermenting guidelines. It is recommended to use a digital pH meter or pH test strips that can measure to at least 1 decimal point. Test strips are less accurate as the color of the food can alter the result and many test strips don’t test to the accuracy of at least one decimal point. For instructions on how to use pH test strips follow these links: https://extension.usu.edu/utahwaterwatch/monitoring/field-instructions/ph/ and an electronic pH meter.
Maintaining Proper Temperature
For the fermentation of food to be successful, the proper temperature must be maintained throughout the entire process. Fermenting on your counter is NOT safe as temperatures vary with weather conditions and heating/cooling fluctuations in the home. It is recommended to use a controlled water bath incubator to maintain a proper temperature. The proper temperature to maintain the “good” microorganisms will be listed on the starter culture packet. Follow instructions on the incubator manual to properly prepare for fermentation.
Monitoring Time
Fermented foods must maintain proper temperature throughout the entire fermentation and reach a pH of 4.6 or less within the allotted time to be considered safe and free from harmful pathogens. The specific temperature and allotted time safety interval your food requires will be listed on your starter culture packet. Dairy products must reach a pH of 4.6 or less within 48 hours to be considered pathogen-free.
Purchasing Starter Cultures
A starter culture is a packet or pouch containing the certain “good” microorganisms that will ferment the sugars and nutrients in the food to produce the desired byproduct acids to ferment the food. A starter culture packet can be purchased online through most grocery retail stores or in person at a local health food store. Starter cultures can not be made at home but after fermenting a food some foods can be re-cultured using a reserved portion. Proper re-culturing needs to occur at least weekly for the “good” microorganisms to thrive and continue to produce.
Popular Foods to Ferment
Acidophilus Milk
Acidophilus milk is a great alternative for lactose intolerant individuals. It is normal milk that has been cultured with live lactobacillus acidophilus bacterium. Research has shown that acidophilus milk has the potential to help prevent or control intestinal infections, improve lactose digestion in lactose-intolerant individuals, help control serum cholesterol levels, and exert anticarcinogenic activity. It can be used in place of milk or if the product ends up thicker then it can be used as a yogurt substitute(Gilliand, 1989).
Buttermilk
Cultured buttermilk is milk that has been incubated with S. lactis and L. bulgaricus. It is a good source of protein, riboflavin, calcium, and several other nutrients. Research has shown that buttermilk may help improve oral, bone, and heart health. Heart health is improved by reduced cholesterol and blood pressure levels. Some lactose-intolerant individuals may tolerate this better than normal milk. Buttermilk is an acid typically used in a variety of recipes as a leavening agent and produces a light color and fine grain when added to baked goods. Buttermilk can be used in pancakes, biscuits, dressings, pies, ice-cream, cornbread, vinaigrettes, or with your favorite meat or cooked vegetable dish(Panoff, 2019).
Cultured Cream (Fraîche)
Cultured cream is a fermented dairy product with 10-45% fat content. It contains probiotics that are beneficial to the gastrointestinal tract. However, this beneficial source of probiotics is high in saturated fat and should be consumed in limited quantities. Commonly known as crème fraîche, this product is highly popular in much of northern Europe and Central America. Crème fraîche is made from heavy cream which is then inoculated with a starter culture and allowed to ferment. It is like the United States’ sour cream except that it is less sour and contains more fat. This thick, delicious treat can be added into savory dishes (curry, casseroles, soups), used as a dip to your favorite fruit, or whipped to top your favorite dessert(Ipatenco, n.d.).
Kefir
Kefir is a drink originally fermented in animal hides made from cow’s or goat’s milk. It originated thousands of years ago from the Caucasus Mountains in the former Soviet Union. Kefir “grains” resemble small cauliflower the size of wheat kernels and contain colonies of yeast and lactic acid bacteria. This fermentable drink is beneficial to the gastrointestinal tract, can help build immunity, improves bone health, has potential protective cancer properties, and may improve allergy and asthma symptoms. Kefir is a good source of calcium, amino acids, B-vitamins, and folic acid. Kefir is also a possible beverage option for lactose intolerant individuals due to its low lactose content. Kefir contains more beneficial probiotic bacteria than yogurt making it the powerhouse probiotic. You can use kefir in smoothies, salad dressings, salads, ice-cream, spreadable cheese, soup, as a substitute for buttermilk or yogurt in baked goods, or as a beverage option (Leech, 2018b).
Kombucha
Kombucha is thought to have originated in China about two thousand years ago. It was originally thought to cure certain diseases although human studies have proven this to be untrue. Research has shown some positive correlations between Kombucha and reduced heart disease risk, the potential to destroy harmful bacteria, aid in the management of type 2 diabetes, and protection against cancer. Kombucha also contains antioxidants and probiotics (Leech, 2018a)
Kombucha is made by brewing sweet tea and then combining with a Scoby starter culture and water. The Scoby then eats the sugar and ferments the tea. Homemade Kombucha contains about 3% alcohol.
Kombucha was introduced to the United States in the 21st century. Since then it has become widely marketed and popular especially due to the wide variety of flavoring options. Flavor Kombucha with your favorite juice, purees, fresh/frozen/canned/dried fruit pieces, fresh/dried herbs, or your favorite jam or preserves. Common flavors include honey lavender, raspberry lemon, blueberry vanilla, peach, strawberry, pineapple, hibiscus, mango ginger, and much more(You Brew Kombucha, 2020).
Yogurt
Yogurt is thought to have originated many centuries ago among the nomadic tribes of Eastern Europe and Western Asia. Milk stored in animal skins would acidify and coagulate. The acid helped preserve the milk from further spoilage and the growth of pathogens (disease-causing microorganisms). Yogurt is a good source of calcium, phosphorous, vitamin B12, riboflavin, magnesium, and potassium. It is also high in protein, especially Greek yogurt. Due to the high amount of protein in Greek yogurt, it is a beneficial appetite suppressant and aid in weight loss as the extra protein leads to longer feelings of fulness, even greater than normal yogurt. Yogurt is also a good source of probiotics. Many commercial brands have been pasteurized destroying the live bacteria. This is a good reason to make yogurt from home to enjoy the benefits of probiotics which are shown to help relieve symptoms of Irritable Bowel Syndrome (IBS) and improve the overall digestive system by decreasing bloating, diarrhea and constipation. Probiotics have also been shown to improve immunity, reduce inflammation, and may help reduce the duration of the common cold. Yogurt also may help prevent osteoporosis and improve heart health(Elliott, 2017).
Choose plain, unsweetened yogurt with live cultures or make homemade yogurt to obtain the most advantageous health benefits. Make yogurt parfaits, smoothies, or frozen yogurt. Yogurt is also making its way to the dinner table in marinades, salad dressings, as a replacement for mayo, swirled into soups, or topped on any of your favorite dishes(Roman, 2014).
Authors
Kelsie Maw, RD, CD; Brian Nummer, Ph.D.; Callie Ward; Melanie Jewkes
Food Safety Specialist
NDFS Dept
Extension Assistant Professor | Economic Development and 4-H Youth Development | Garfield County
Home and Community Department
Phone: (435)-676-1113
Email: callie.ward@usu.edu
Office Location: Garfield County
Extension Professor | Family & Consumer Sciences | Salt Lake County
Home and Community Department
Phone: 385-468-4838
Email: melanie.jewkes@usu.edu
Office Location: Salt Lake County
Related Research
Avoid these ten potentially deadly canning mistakes, as well as other food-specific mistakes that you'll want to avoid. This will keep your food fresh, healthy, and safe to eat.
Freeze-dried foods are extremely popular among backpackers and culinary masters, and now freeze-dryers are available for home use. But is a home freeze-dryer the appliance for you? Here is some information designed to cut through the advertising hype and
Since 2000, Extension has been warning consumers about canning cakes and breads. While this process has much appeal, it does not destroy the organism that causes botulism.
Learn how to the traditional British dessert of lemon curd. Canned, it has a shelf life of 3 to 4 months. If you don't mind the darkening that occurs, it can last up to 1 year.
Follow specific proper canning guidelines for chicken, beef, seafood, and others. These guidelines will ensure your food is safe to eat.
Canning salsa is a great way to use your tomatoes. Learn how to correctly and safely can salsa with this approved recipe.
Pieces of food taken from the drying trays are not always uniformly dry. To condition, place cooled dried fruit loosely in large plastic or glass containers, about two-thirds full.
Some essentials are needed to cook with the main food staples in long term food storage. These mostly are used to make breads from stored grains. The cooking essentials include salt, baking powder, baking soda, and yeast.
Making jerky safely requires either the use of curing salts (containing nitrite) or enough heat in an oven or dehydrator so that the heat will kill organisms before they multiply.
Moisture and temperature are the two critical factors in optimal food storage. Moisture - the humidity in the storage environment should be low. If dried foods pick up moisture from the storage area, molds and bacteria can grow. This can lead to spoilage
A few packaging methods for your food storage and food that is being preserved. Methods including foil pouches, glass canning, and plastic bottles are discussed.
Congratulations! You are now the owner of a new freeze-dryer; or you are ready to make the purchase! While the freeze dryer itself is a major investment in food preservation equipment, you will want to make certain you are prepared with a few other items
Freezing is a simple, quick way to preserve foods. Fruits freeze well and retain their distinct fruit flavor. Texture is usually softened somewhat by freezing, but serving partially frozen fruit with ice crystals will compensate for texture changes.
Crispness is a hallmark of a good pickled vegetable. That crispness comes from the vegetable’s natural pectin.
Lately, some people have been advocating some very potentially hazardous food preservation and storage practices on foods meant for room temperature storage.
The proper methods of drying are one of these four methods: Air drying, sun drying, oven drying, or dehydration. Learn how to properly do each of these methods.
Learn the value of drying foods at home, the nutrition that you will have from dried foods, and how to set yourself up for success while drying.
The proper methods of drying are one of these four methods: Air drying, sun drying, oven drying, or dehydration. Learn how to properly do each of these methods.
Apples are a favorite fruit of many people for eating out of hand, in fresh salads, or in a wide variety of cooked products. Here's how to preserve Apples
Instructions on preserving apricots from USU Extension.
Learn how to safely preserve berries through a variety of methods, such as canning, freezing and other methods.
Learn how to preserve cherries through a variety of methods such as freezing, canning, and drying. Also find recipes for cherry pie filling, cherry raisins, jam, and more.
Did you know that there are many ways to preserve your chiles? This resource offers the resources you need to learn how to freeze, can, dry, and store your chiles!
How to dry, bottle and freeze corn by Utah State University Extension faculty.
Learning how to select, can, freeze, dry, and store grapes doesn't need to be complex! USU Extension has all of the resources that you need to preserve your grapes in the way that you prefer to do so.
The process of selection, preparation, freezing, canning, drying, and storage of peaches to enhance preservation and storage.
The most popular variety is Bartlett pears available the first two weeks in September in Utah. If they are to be transported or not processed immediately, pick while slightly green and allow them to ripen in a cool, dark place.
There are many good bean varieties for sale in local gardening outlets and through seed catalogs. Most grow well in Utah. Pod shape, size, and color vary among varieties. Here is a list of some potential varieties and plant types that have performed well
Pomegranates are great for canning, freezing, storing, and more! USU Extension has the resources to guide you through the process, as well as teach you how to make syrup and jelly.
Most varieties of summer squash do well throughout Utah. All squash prefer organic, rich, well-drained, sandy soils for best growth.
Learn how to safely preserve tomatoes through a variety of methods, such as canning, freezing and other methods. Also find recipes to use while preserving tomatoes, such as tomato juice or tomato sauces.
Preparing and handling venison comes in a variety of important steps! This resource offers instructions and information on canning, handling, drying, recipes, storage, and more!
USU Extension has the resources for you to prepare, freeze, steam, can, pickle, dry, and store your zucchini!
Understanding when hydrated wheat is ready to use is very important. This resource offers insight into safe instructions to do so.
This article discusses the basic principles of pressure canning.
Only in recent years has the amount of sugar consumed in the American diet been questioned. About half of the total energy consumed in the average U.S. diet is from carbohydrates.
Canned foods can either be purchased commercially or home canned. Home canned foods should be canned using research-tested recipes and processes like those found in the USDA Complete Guide to Canning or in Extension publications.
Non-fat dried milk (NFDM) is suitable for short and long term emergency food storage. It is made from non-fat, grade A, milk that has been dried by spraying into hot air or heated on a drum. The process removes nearly all of the water prohibiting the grow
Legume (Bean) varieties such as: Adzuki, Black, Black-eyed, Black Turtle, Garbanzo, Great Northern, Kidney, Lentils, Lima, Mung, Navy, Pink, Pinto, Small Red, Soy, and Split-pea can all be dried and stored.
Storing eggs safely is important for your health and that of your family.
Sugars are simple carbohydrates that provide an excellent source of calories for energy. Sugars also add the sweet taste to many of our most delicious foods. Sugar can be stored in dry form (crystals) or in a liquid form (syrup –including maple syrup).
If the supply of safe water is cut off during an emergency, it is important to have water stored. Learn how to store water safely and where you can find an emergency source if needed.
Article on storing wheat from Utah State University Extension.
White rice, more commonly known as polished rice is a main food source for over half of the world’s population. Rice is an excellent addition to home food storage because it’s versatile, high caloric value, and long shelf life. Families should store about
You can determine when the product is dry by feel or by calculation of the amount of water remaining in the product.
Fermenting foods is perhaps the oldest food preservation method and has grown in popularity in recent years due to their touted “gut”, probiotic, and other additional health benefits. Fermenting at home is an inexpensive way to control what goes inside yo
Due to the lack of definitive research into the safety of steam canning the Utah State University Extension program currently agrees with the present USDA and National Center for Home Food Preservation recommendation against usin
Canning never improves the quality of the food you are preserving. Come learn the general guidelines for best results when canning vegetables.
Choose fresh, tender vegetables. The fresher the vegetables, the more satisfactory the final product. Tips on selecting, preparing, and freezing vegetables.
Electric Programmable Pressure Cookers, such as the "Instant Pot, are being used for small batch pressure canning. This fact sheet explains research showing why this is a food safety hazard, with a high risk of producing home canned foods that could devel
PreviousNext