Fermentable Carbohydrates: List and Details

Across fermentation industries – brewing, winemaking, distilling, even breadmaking and fermenting foods, understanding fermentable carbohydrates is critical to true success.

For most in the business of fermenting, experimentation is a crucial element of mastering the craft of food and beverage creation.

Thus, getting familiar with a fermentable carbohydrates list and the details involved in the process can only enhance your craft.

What Is Fermentation?

To begin, it helps to review fermentation.

Recall that fermentation simply refers to the chemical process of breaking down a substance, which creates another substance.

At its most basic definition, fermentation is just the creation of energy.

There are two fermentation processes: alcoholic and lactic acid. The former requires yeast and the latter bacteria.

Free Yeast Analysis

 

With yeast, the single celled organism seeks out sugar for energy and reproductive purposes. When yeast senses sugar, it will consume it, which allows for the mother cells to produce a daughter cell, which grows from the mother until she reaches more than 50% volume of the mother, at which point she breaks off and then can consume sugar and reproduce herself. This process is called asexual reproduction and can be done numerous times during a single yeast cell’s lifetime.

Sugar is the key.

As a waste product of this process, alcohol and carbon dioxide, along with hundreds of other secondary metabolites are created. Lucky us.

So, when we make beer, wine, cider, or liquor, yeast consumes whatever sugars are present in a mixture – ground and boiled grain water (wort), crushed grapes, boiled fruit juice – and then converts those sugars into alcohol and carbon dioxide, thriving all the while.

In lactic acid fermentation, bacteria consumes the sugars present in the food and breaks it down to digestible and usable vitamins and minerals beneficial to humans.

There is also the form of lactic acid fermentation that takes place in the human body when we need more energy fast. As we breathe too fast, while we are running, for example, our cells undergo fermentation that quickly converts our carbohydrates to ATP for energy.

What Are Fermentable Carbohydrates?

The question then becomes “what are fermentable carbohydrates?”

Are they all fermentable?

Well, no.

But most are fermentable at least to some degree.

The list of fermentable carbohydrates falls under three primary headings: sugars, starches, and fiber.

Sugars

Sugars are the simplest type of fermentable carbohydrate, which is why they are so prevalent in so many fermented foods. Sugars are made up of one or two sugar molecules and include glucose, fructose, and sucrose.

In the fermentation industry, we typically see fermentable sugars show up in toasted grains like barley, oats, wheat, and corn, as well as in fruits like grapes, apples, and pears.

Toasting grains converts their starches to sugars, which are much more difficult for yeast to break down.

For brewers, in particular, the most important and common fermentable carbohydrates include maltose, maltotriose, glucose, fructose, and sucrose.

  • Maltose is the primary sugar found in malted grains, such as malted barley. During mashing, maltose is broken down by enzymes (amylases) and provide yeast with a readily fermentable sugar source.
  • Unlike maltose, which consists of two glucose molecules, maltotriose, another sugar found in malted grains, is composed of three glucose molecules. This makes it less fermentable than maltose, but it is still an important component of the wort, as yeast can and will ferment it.
  • Glucose is a simple sugar and it’s the most preferred by yeast, as it is easily fermentable. However, it is present in small quantities in malted grains, although some brewers also choose to add glucose directly to the wort to provide the yeast with more of this highly fermentable sugar.
  • Fructose is not something you would expect to see in brewing, as it is a sugar that naturally occurs in fruits, honey, and some vegetables. But it can be present in the wort through adjuncts used in beer production, such as syrups or even fruits.
  • Sucrose is also an unusual presence in beer, but some brewers do add sugar to their wort to boost its fermentable sugar content.

Starches

Starches, as noted much more difficult to ferment, include wheat flour, corn starch, and potato starch. Unless these starches are toasted or roasted in some way to convert their starches to sugars, yeast has a more difficult time fermenting, and so the end result is much lower in alcohol and carbon dioxide.

Think of bread, or even early ales where the ABV was close to 1%.

Fiber

Fiber is a type of carbohydrate that cannot be broken down by yeast, but it can be fermented by bacteria, which is what we see with fermented foods like kimchi and pickles.

Non-Fermentable Sugars

When we discuss fermentable carbohydrates, we are really wondering, often, about those non-fermentable sugars.

While brewers and winemakers, bread makers and distillers can experiment with oats and zucchini, grapes and quinoa, there are a few sugars that are simply off limits and will not ferment either for yeast or for bacteria.

Those include xylitol, erythitol, stevia, splenda, lactose, and maltodextrin.

Thus, you cannot hope to ferment any food or beverage using these sugars, but you can sweeten them and trust that fermentation will not continue or increase with their addition.

This option for sweetening is often used with ciders, where you want a lower level of alcohol, but you want to increase sweetness. Rather than adding sugar, which will only increase the ABV once the remaining yeast gets a hold of it, you can add Stevia after fermentation.

Fermented Foods

Fermented foods are any foods that have undergone lactic acid fermentation, and the list is virtually endless.

You can ferment dairy, of course, for yogurt. The list also includes:

  • Tempeh
  • Miso
  • Kimchi
  • Sauerkraut
  • Pickles

And more.

Alcoholic Fermentation

Alcoholic fermentation must include yeast but it can also include bacteria. The list includes:

  • Beer
  • Wine
  • Liquor
  • Sake
  • Cider

And even kombucha, which calls for SCOBY, a combination of bacteria and yeast.

Experimentation Is Key

In the end, experimentation is key. Foods high in fermentable carbs will be those high in starch or sugar, think of potatoes and corn, barley and super sweet fruits and vegetables like strawberries or sweet potatoes.

But don’t stop there.

If you’re using wild bacteria, you can also explore your options with brussel sprouts and asparagus, artichokes and squash.

The combination of yeast and bacteria allows for so much potential when it comes to fermentation.

If you are seeking to avoid fermentable carbohydrate foods, you would look to foods like avocados, oranges, bananas, cherries, mushrooms, and other foods that have resistant starches.

But even those foods could add interesting flavor profiles to fermented foods and beverages.

The key, as always, lies in the willingness of the craftsman or craftswoman to be open to new flavors and aromas, new ways of thinking about fermentation, and of course, to failing miserably along the way.

It’s all about the learning process, right?

Cheers!

Passionate about the fermentation process? So are we! If you’re interested in finding out how you can use our technology to control fermentation and monitor your yeast, save work hours and improve the cost-efficiency of your business, drop us a line at [email protected] or check out our product pages:

Also, you can now get access to a fully functional demo account to test your yeast via our Web App. Completely free of charge and with no commitment to purchase.

Sources:

  1. https://cancanawards.com/fermentable/
  • Publications

    Best Pattern Recognition Software

    A review of the best pattern recognition software for those interested in the various applications, including colony counts, bacteria identification, and more.

    Read more
  • Publications

    Petri Dish Bacteria Identification Chart: Why Use One

    This article is dedicated to those in the lab wondering whether a comprehensive petri dish bacteria identification chart could make their job easier.

    Read more
  • Publications

    Is Bioethanol Good for the Environment?

    Have you been asking the question, “Is bioethanol good for the environment?” This article describes the role of bioethanol from an environmental perspective.

    Read more
  • 0
      0
      Your Cart
      Your cart is empty