The keto weight-loss diet emphasizes a diet that is about 70% fat, 20% protein, and 5% each simple carbohydrates and non-starchy vegetables. Such a diet forces the body into a metabolic state known as ketosis, which is when the body burns fat instead of carbohydrates for energy. The liver converts fat into fatty acids and ketone bodies, with the latter traveling to the brain and fueling the body, the traditional role of glucose obtained from carbohydrates. Burning ketones in place of glucose is associated with weight loss, reduced inflammation, sustained energy and more.
Foods labeled keto-friendly appeal to consumers who are limiting sugar and total carbohydrate intake.
Keto is not legally defined; however, most keto dietary plans suggest a daily intake of less than 30 grams of net carbohydrates. To put that in perspective, three Oreo cookies contain 24 grams of net carbohydrates. While “net carbohydrates” is also not legally defined, it refers to carbohydrates that the body digests and includes sugars naturally found in everything from fruit to milk, as well as caloric carbohydrates, such as wheat flour, oatmeal and other grains. Most calculations are made by taking the total carbohydrates in a food and subtracting fiber and sugar alcohols.
The main challenge with yeast-leavened applications is creating a flour replacement system that is not only low in carbohydrates but also functional, Daniel Marciani, research manager, bakery, Glanbia Nutritionals, pointed out.
“Once this is accomplished, the manufacturer still encounters the issue of supplying yeast with fermentable sugars while not adding sugar to the mix,” he said. “Bread doesn’t necessarily need sugar to rise, but it helps to hit short proof times.”
Tim Christensen, a certified master baker, Cargill, suggested that bread is the most challenging baked food for keto-friendly formulation.
“Trying to get rid of all those carbs and still create something that looks like traditional bread is no easy task,” he said. “One of the biggest challenges with keto in breads, as well as other baked goods, centers on moisture. When you take out starches and other carbohydrates, you’re also taking out all the ingredients that hold water. Formulators tend to replace these ingredients with nut flours, which hold very little moisture. As a result, you wind up with products that are often very dry. ”
MGP Ingredients offers an RS4 resistant wheat starch (greater than 90% total dietary fiber on a dry basis) and several wheat protein isolates as part of its keto ingredient solutions line. This makes it possible to create yeast-leavened and chemically leavened baked foods, everything from breads to bagels and cakes to cookies.
“Yeast-leavened keto-friendly bakery products are challenging to formulate because the conventional use of sugar, a high-carbohydrate source, for flavor and as a substrate for the yeast is typically avoided,” said Tanya Jeradechachai, vice president of ingredient solutions, MGP Ingredients Inc. “This results in a finished baked product with a light-colored crust (less browning) and a smaller loaf volume due to less leavening action by the yeast.”
Starch is another critical component of wheat flour that isn’t keto-friendly but very functional in a bread formulation. Ms. Jeradechachai said the company’s RS4 resistant wheat starch functions in a similar way to baking wheat starch while still minimally contributing to net carbs.
“When we use RS4 wheat in baking, we also incorporate wheat proteins to impart viscoelastic properties,” Ms. Jeradechachai said. “We have six wheat protein isolates that differ in their elasticity and extensibility properties and can provide clean label opportunities.”
Corbion developed a keto-friendly yeast-leavened bread. Key ingredients are resistant starch, wheat protein isolate, vital wheat gluten, oat fiber, yeast, oil / shortening, salt, inulin and enzymes. The enzymes improve dough structure, which results in higher loaf volume and finer cell structure. They also enhance crust color and provide some sweet flavor without significantly changing the total net carbohydrate content.
Non-keto-friendly ingredients – wheat flour, sugar, starch – provide some of the most significant functionality in baked goods.
“The tenderness you get from soft wheat flour and sugar can be difficult to match,” said Brook Carson, vice president of research and development, Manildra Group USA. “It can be done with a strategic balance of proteins and fibers.”
Manildra Group’s keto ingredient system includes resistant wheat starch, which provides the starchy component. Wheat protein provides structure.
“Wheat proteins are available with a wide variety of functional attributes that can contribute to the optimal texture for these products. With varying degrees of elasticity and extensibility, it is easy to achieve the optimal rheology throughout the process and eating properties in the finished product, ”Ms. Carson said. “Resistant wheat starch is the preferred fiber because it does not have a considerable impact on the absorption or processing characteristics when compared to other fibers.”
Finding an ingredient system can provide a keto-friendly path forward rather than a single ingredient.
“The key to successfully creating our low net-carb flour blend was achieving the right balance and combination of dietary fibers and grains,” said Lindsey Morgan, head of product marketing, Ardent Mills. “It is made without the addition of nuts or nut flour and contains gluten, allowing customers to run on their current equipment without significant changes.”
Dairy proteins can also be part of the solution. Unlike most plant proteins, dairy proteins are complete proteins, meaning they contain all nine essential amino acids in the proportion best used by the human body. This further contributes to the keto-friendly product’s healthful halo.
“Casein-based ingredients, such as milk protein concentrate and micellar casein concentrate, will bind more water than whey protein concentrate or isolate,” said Kimberlee Burrington, director of training, education and technical development at the American Dairy Products Institute. “Depending on the protein used, the formulation might require more water to make a dough workable. Additional water means you will have more to bake out. ”
Glanbia Nutritionals developed a line of flour replacement solutions that can be used for keto-friendly baked goods. It includes a flour replacement designed for yeast-risen breads that supplies an excellent source of (dairy and plant) protein in one serving of bread.
Pea protein has become a popular plant-based option. The challenge here is that it is not a complete protein. It also brings a flavor profile that is not typical for baked goods.
“While flavor maskers can help with this off flavor, the development tool most appreciated by consumers is to bring a high level of sweetness that will effectively ‘mask’ the pea protein,” said Casey McCormick, director of product development, Sweegen. “Monk fruit is often paired with stevia to deliver a higher level of sweetness in the finished good. Using these together can deliver the most sweetness without overemphasizing the linger that can be observed when they are used individually at higher levels. ”