WESTCHESTER , Ill. — Predictions for the plant-based food category are promising, some bolder than others. MarketsandMarkets, Northbrook, Ill., recently forecast the global plant protein market to have a compound annual growth rate of 7% to reach $14.5 billion by 2025.

Kees Kruythoff, chairman and chief executive officer of The Livekindly Collective, New York, has a loftier prediction for plant-based foods: $400 billion to $500 billion in global sales by 2040.

Whether such figures are reached will depend on how industry solves taste issues, scales up production and targets consumers. Appealing to teenage daughters could help, and the food industry could take cues from transportation innovation in the early 20th century.

Mr. Kruythoff spoke March 3 in a panel organized by Westchester-based Ingredion, Inc. The panel was part of a virtual event that showcased Ingredion’s new plant protein facility in South Sioux City, Neb.

Mr. Kruythoff worked for Unilever PLC for 27 years before Livekindly, which has ownership in plant-based food brands, was founded last year. Younger consumers, including millennials and Generation Z, are leading the interest in plant-based eating, Mr. Kruythoff said.

“Especially daughters between the ages of 14, 15, 16, they come home, and they say to their parents, ‘Why do we ever eat animals?’” he said.

Whether the family listens to the teenage daughter and switches to more plant-heavy meals could hinge on price. Plant-based meat alternatives can be two to five times the cost per lb of animal-based meat, according to Rebellyous Foods, Seattle, which offers plant-based nuggets, patties and tenders. Christie Lagally, a mechanical engineer and CEO of Rebellyous Foods, said the company is designing the next generation of food processing equipment to bring down the costs of plant-based food.

“Where innovation really comes in is the ability for our industry to respond to that incredible demand, to make sure all those 14-, 15-, 16-year-olds can convince their families that a better product is out there because it’s now going to be affordable,” she said.

Ms. Lagally gave an analogy of industry’s increasing need for more transportation about 1910, a time when horses and wagons still transported many goods. Some thought the horse industry could solve the transportation problems.

“Bigger and bigger horses,” she said. “We’re just going to breed bigger horses. When in fact actually what we needed was an axle and a wheel and an internal combustion engine.”

To meet the increasing demand for plant-based food, innovation and out-of-the-box ideas will be needed along with scaling up production, she said.

“So we don’t need a bigger horse,” Ms. Lagally said. “We want a new tool.”

Both Ms. Lagally and Mr. Kruythoff said the price of plant-based meat alternatives per lb could drop to the price of animal-based meat per lb in as soon as three years.

“I think as long as we’re hitting both sides of the equation — the scale and the per-lb-price problem that requires innovation and technology — I think three to five years,” Ms. Lagally said.

Mr. Kruythoff said further growth in the plant-based category could come by targeting consumers by segment since they have different motivations for eating plant-based foods: Some do so for health reasons, others for animal welfare and others as a way of doing what’s good for the planet.

Using the term plant-based eating is moving the category forward more so than the terms vegetarian or vegan, said David Meyer, strategic adviser for the Plant Based Foods Association, San Francisco.

“It’s not so all or nothing like it used to be,” he said. “You were a vegetarian or you weren’t a vegetarian.”

Perception of the term “vegan” has improved recently, though, he said.

“I think there’s been some rehabilitation of the term vegan with a lot of celebrities embracing that,” Mr. Meyer said. “It opened up a lot of young people’s eyes as a cool way of eating.”

Panelists gave their views on rising sources of plant-based protein and up-and-coming meat alternative categories.

Peas are “the new kid on the block” because of their functionality and attributes that appeal to consumers, said Caroline Bushnell, director of corporate engagement for The Good Food Institute, a nonprofit involved in alternative proteins.

“In addition to pea, other legumes like chickpeas are really interesting,” she said. “We’re seeing seaweed. Gosh, there’s just like a whole list of them: quinoa and hemp and oats. A lot of these aren’t really produced at a scale yet to really be used in large quantities.”

Ms. Bushnell said improvements in the whole muscle area could speed up adaption of plant-based meat alternatives, adding a marbled state would be a “holy grail.”

“That’s going to be critical in chicken and fish,” Ms. Bushnell said. “Right now, we have very limited fish products.”

The number of alternatives for chicken, including breasts, and fish, including fillets, should increase in the next three to five years, Mr. Meyer said.

“I think consumer education is going to come on, and people are going to understand that those products also have terrible environmental and animal welfare impacts,” he said.

Thanks to technology, a chicken breast alternative should be available in about three years, Mr. Kruythoff said.

“The next thing is all about chicken,” he said.