Fermented foods: The other probiotics

Jennifer Dalton, MS, RDN, LD, is the director of didactic program in dietetics at the University of Dayton. She teaches courses on nutrition and health and is an expert on functional nutrition, celiac disease and digestive health. Email: jdalton1@udayton.

Walking through my local grocery store last week, I noticed a new trend in foods that may have a beneficial effect on gut health. Foods like kefir milk, sauerkraut, fermented salsa, miso and khombucha are increasing in numbers in local grocery stores and restaurants.

Although this food trend may seem new to you, it is actually a practice that has been around for approximately 10,000 years. Fermented foods date back to 6000 BCE with alcohol representing one of the earliest fermented foods reported in cultural food practices. As agricultural farming progressed dairy, grains, fruits and vegetables were added to the fermentation process. While fermentation is used to preserve foods it’s medicinal properties have been valued for thousands of years in Eastern medicine.

Fermentation is the most ancient form of food processing and one you likely saw your grandparents practice with their summer vegetables. It is a process that begins with a bacterial source that is introduced to a carbohydrate food source that the bacteria can consume. The good bacteria continue to grow resulting in changes to flavor and texture in the food product. These products may have several strains of good bacteria, probiotics, which may be the reason they contribute to a healthy digestive tract. Since these foods are made with live bacteria individuals with compromised immune systems should talk to their physician before consuming these products.

Sources of fermented foods in the United States tend to be limited to yogurt, sauerkraut, sourdough, and pickles. While these sources provide exposure to probiotics there are more ways we can add microbial diversity and flavor to our diet throughout the week. Below are a few fermented foods that can be found in your local grocery store:

Kefir milk: Often referred to as the "champagne" of dairy the fermentation of bacteria contributes to its tart flavor and fizzy characteristics. Kefir contains more probiotic strains than yogurt and contains a type of yeast that works with the probiotics to maximize beneficial effects to the gut. Kefir is found in the dairy section of the grocery store near the milk or yogurt and comes in a variety of flavors. For those put off by its tart taste Kefir milk can be added to a smoothie in place of yogurt.

Khombucha: Is a fermented tea that is deeply rooted in Asian cultures for thousands of years. Once considered the tea of immortality this product is fermented with live bacteria, sugar and yeast. Once fermented, this product may have a strong vinegar taste or juice can be added to sweeten the tea.

Tempeh is a food originating in Indonesia and is made by fermenting cooked soybeans with Rhizopus mold. This process allows the beans to bind together which gives it a firm texture and nutty flavor. Tempeh can be enjoyed as a sandwich, in salads, or in stir-fry dishes. It can be purchased in grocery stores and is often on the menu at restaurants catering to vegetarian diners.

Miso: Is a paste is used in Japanese foods as a flavoring or spread. Miso ferments by adding a mold, Aspergillus oryzae, to a grain (usually rice, barley or soy) and allowing the mixture to age. Miso is found in the refrigerated section healthy foods section in most groceries. Be sure to add this paste to soup at the end of cooking to avoid killing the bacteria in the cooking process.

Fermented vegetables (salsa, sauerkraut, Korean kimchi): Many cultures ferment vegetables as a method of preserving summer vegetables. The process involves combining vegetable with salt and storing in airtight container. Bacteria naturally present on the vegetables reacts with the mixture to create vinegar. These foods can have a crunchy texture and tangy flavor. They can be consumed alone as a side dish, as a topping to a sandwich, or as a dressing to a fresh green salad. Most fermented vegetables are found in the refrigerated produce section in grocery stores.