KANSAS CITY — Plant-based alternatives for hamburgers and chicken nuggets increasingly appear on menus and in frozen food aisles, testifying to consumer acceptance of the products. Now comes a trickier challenge for food innovators: creating similar alternatives for whole-muscle cuts like steaks, chicken breasts and fish fillets.

Difficulties arise in matching the marbling aspects of muscles, the specific colors associated with the items — both before and after cooking — and the nutritional qualities.

The value of plant-based meat alternatives reached $1.4 billion in 2020 as sales grew 45% from $962 million in 2019, according to data from the Plant Based Foods Association and The Good Food Institute. Yet the quality of the products still could improve, according to ADM’s Outside Voice research portal. Half of flexitarian consumers (those cutting back on meat consumption) agree meat alternatives need taste improvements, according to Outside Voice, and more than 20% say texture needs to be improved.

“There’s a host of challenges to achieving the perfect plant-based steak,” said Melissa Machen, senior technical services specialist, plant protein, for Minneapolis-based Cargill. “Perhaps the biggest hurdle is creating muscle-like fibers that will deliver the firm bite consumers expect from a steak. Technological advances like wet extrusion are narrowing the gap, but these processes can be expensive.”

Marbling is the intramuscular fat between fibers in a muscle, said Michael Cropp, technical service associate for Kemin Industries, Des Moines, Iowa.

“The marbling offers a consumer a more juicy and flavorful eating experience,” he said. “Beef, for example, is graded based upon the amount of marbling."

Vegetable oils like coconut oil and palm oil may be used to impart the “marbled state” in plant-based steak alternatives or plant-based burger alternatives, said Tanya Jeradechachai, vice president of ingredient solutions R&D for MGP Ingredients, Atchison, Kan.

“However, vegetable oils are liquid at room temperature, which makes it very challenging to achieve a marbled appearance in the product,” she said. “To resolve this problem, the oil can be blended with other ingredients like gums and starches at cold temperature resulting in a solid material that can be reduced in size to resemble small pieces of fat particles. The fat particles can then be incorporated into a plant-based steak or burger at cold temperature to assume a marbled appearance.”

Juicy Marbles, Ljubljana, Slovenia, has created plant-based filet mignon alternatives with its Meat-o-matic Reverse Grinder 9000. Layering soy protein into linear fibers mimics muscle texture, according to the company.

“The biggest challenge was getting the right fiber alignment and intramuscular fat structure — the marbling,” said Luka Sincek, one of the founders of Juicy Marbles. “The most expensive steaks in the world are known for their lush marbling. It takes a lot of energy and a rare breed of cow to attain that. With plant meat, we control it and, thus, over time, can scale up our steak production and bring down the price. Eventually, we’ll be able to make the most premium meats attainable for everyone.”

Plant-based fillet mignon

Companies need to create a plant-based fat system that appears like conventional steak marbling, and they also need to incorporate and bind the fat system in plant-based “muscles” so it appears like marbling in steak, said Vineet Jindal, PhD, customer innovations manager – plant-based food for AAK USA, Inc., Edison, NJ.

“In addition, the marbling also needs to release the aroma of conventional steak during and after cooking,” he said. “The integrity and appearance of the steak also need to be maintained during and after cooking. Creating a three-dimensional steak with all the challenges of marbling with plant-based materials is therefore taking a longer time as compared to ground meat products like burgers and meatballs.”

Ingredient selection may help in savory taste, said Christopher Naese, vice president of business development for Florida Food Products, Eustis, Fla.

“FFP’s fermented mushroom juice provides a natural source of umami and coupled with mirepoix and onion concentrates deliver great savory taste in a clean, consumer-friendly way,” he said.

Color is difficult to replicate as well.

“Consumers expect a bright red color when the product is cold, but when it’s cooked, it should have a nice brown color on the outside, yet look somewhat rare in the middle,” Ms. Machen said. “That is incredibly difficult to achieve with our current ingredients and technologies. However, there are advances coming, including wet-moisture extrusion and even cell-based products, that may help brands get much closer to the textures, colors and sensory experiences of traditional meat products.”

Technology for chicken alternatives

ADM’s Outside Voice found 61% of US plant protein consumers have tried chicken or poultry alternatives. Some alternatives, like breasts, will be more difficult to replicate than others, like nuggets.

In a whole-muscle chicken breast, the cross-linking and structure of a muscle is complicated, Mr. Cropp said.

“Similar textures might be achievable through specific mechanical action to give texture in a pattern similar to a muscle fiber running through a chicken breast,” he said.

High-moisture extrusion commonly is used to make chicken breast alternatives, Ms. Jeradechachai said.

“The plant protein ingredients, which could be from pea, wheat, soy or their combinations, are plasticized and texturized in a long cooling die by varying the moisture, temperature, pressure and shear,” she said. “The resulting product assumes a whole-muscle appearance possessing a fibrous structure. Plant protein concentrates and isolates, gums and flavorings are commonly used as ingredients.”

Wheat gluten has served as the base of vegan chicken products, said Dawn Crampton, product development and innovation manager for Purefield Ingredients, Russell, Kan.

“The process begins with a dough (seitan), which can be shaped and processed to mimic the texture of a chicken breast,” she said. “It is easily flavored to create a unique experience for the consumer. Blending in additional proteins can provide a complete nutritional profile, if desired.”

New technologies are allowing companies to progress from ground formats to pulled, shredded and diced meats, and nuggets, said Dina Fernandez, global director, protein nutrition solutions for Chicago-based ADM.

“One solution for creating whole-muscle products is using twin-screw high-moisture extrusion,” she said. “Additionally, we’re seeing significant growth around formulating whole-muscle products, including new functional ingredients and improved extrusion technologies for better long-fiber textures and elevated flavor.”

ADM uses its lineup of Arcon and ProFam 974 soy proteins for high-moisture extrusion.

“These solutions are exceptionally functional for meat alternative formulations that require high solubility, gelling capacity, elasticity and increased nutritional quality,” Ms. Fernandez said.

The right fish flavor

In fish alternatives, fillets and whole cuts are more difficult to produce when compared to unstructured products like patties, flakes or textured products, Ms. Crampton said.

“For example, a salmon fillet has a complex structure that would require a long ingredient list of proteins, gelling agents and starches to achieve, not to mention the marbling required,” she said. “We have seen some success with mushroom and pea proteins. However, this remains an area to explore further.”

Trying to mimic the white appearance and flaky texture of fish like cod can be difficult when working with plant-based proteins, Ms. Machen said.

“It starts with protein selection,” she said. “Finding a protein that is light in color, like soy protein concentrate and soy flour, is a must. Then we turn to other ingredients to fill in the gaps. Our SimPure potato and tapioca starches are very white, so they can help with color, plus they have excellent water-binding capabilities and label simply.

“This is another space where wet extrusion can play a role, helping to create strips or chunks that better replicate the appearance and flaky texture of many fish products.”

Plant-based meat alternatives made with algal oil

Taste and color come into play in fish alternatives, too.

Royal DSM, Heerlen, The Netherlands, has developed Maxavor Fish YE, a vegan, allergen-free flavor system derived from algal oil to emulate the body, mouthfeel and taste of distinct fish varieties. Flavors may replicate those of rich and oily dark fish or those of fresh, light and fleshy white fish.

Plant-based tuna and salmon alternatives, because of the coloring agent needed to mimic their natural colors, are difficult to create, Ms. Jeradechachai said.

“Colors derived from tomato for tuna and carrots for salmon have been mentioned,” she said. “MGP’s light color version of textured wheat and pea protein products can easily pick up the added color to simulate the tuna or salmon product.”

Finally, plant-based fish alternatives should provide the necessary amino acid and fatty acid profiles that make conventional fish healthy, Dr. Jindal said.

“The omega-3 fatty acids, DHA and EPA, are of primary importance when creating plant-based fish products with a similar nutritional profile to traditional fish,” he said. 

Ingredient lists draw attention in meat alternatives

More consumers are seeking plant-based meat alternatives, and they are analyzing ingredient lists, too. Ingredients perceived as clean label and shorter ingredient lists may draw their attention.

Among US consumers, 25% said they were buying more plant-based meat alternatives during COVID-19, according to 2020 research from Ingredion, Inc., Westchester, Ill. Among North American consumers, 50% said they would pay more for products with plant-based ingredients. When asked to list their preferences for plant protein sources, 46% said lentils, which was followed by chickpeas at 44%, peas at 39%, soy at 37% and quinoa at 36%.

ADM’s Outside Voice research portal found 83% of flexitarian consumers (those trying to reduce meat consumption) review product labels.

“Plus, 66% of consumers say they are looking for labels with the shortest ingredient list, and 69% of consumers say simple, recognizable ingredients influence their purchasing decisions,” said Jacquelyn Schuh, product marketing director, protein nutrition solutions for Chicago-based ADM.

Blending plant proteins, besides improving structure and texture, may shorten ingredient lists, said Dawn Crampton, product development and innovation manager for Purefield Ingredients, Russell, Kan.

“Choosing proteins that have different but symbiotic functionality can reduce or eliminate other ingredients such as stabilizers, gelling agents or binders,” she said.

Formulators should ensure every ingredient in a product provides a unique functionality, like texture, flavor and mouthfeel, said Vineet Jindal, PhD, customer innovation manager – plant-based food for AAK USA, Inc., Edison, NJ.

“Some ingredients can provide multiple functionalities, like fat and oils can provide both mouthfeel as well as taste and binding,” he said. “Ingredients with multiple functionalities can help minimize the use of several ingredients in the same recipe. Similarly, cleaner tasting proteins will minimize the need of using flavors and spices.”