Students at the Natural Gourmet Institute in their "Pates and Terrines" class.

In a Manhattan culinary academy, apron-clad students from around the world listened to their chef instructor narrate how to prepare a classic: pâté.

But unlike the conventional French recipe, the ingredients were not duck or chicken liver, but rather sundried tomatoes, sunflower seeds and rosemary. Or, in another vegetarian variation, porcini mushrooms and walnuts.

“It’s easy to make something taste good with butter and meat,” said student Kristen Saberito, who previously carried trays of salami, corned beef and French fries at the deli she worked at for four years. Vegetarian food, she said, is a much greater challenge, which is why she enrolled at the Natural Gourmet Institute for Health and Culinary Arts.

In recent years, vegetarian and natural culinary schools in the United States have seen their enrollments swell–fueled in part by a more health-conscious public. They are experiencing a growing demand for their style of cooking–which mixes creativity with healthy ingredients– from restaurants, individual clients, wellness centers, and even school lunch programs.

At the Natural Gourmet Institute, “we’re making alternatives to non-vegetarian food that pleases the same way even if it doesn’t taste the same way,” said Jay Weinstein, the chef instructor, after his “Paâtés and Terrines” course at the Institute, located in the bustling Flatiron district of New York City.

There are at least eight vegetarian or natural culinary schools in the United States. Like the 33-year-old Natural Gourmet Institute, many originally catered to a more niche audience of health restaurants and individuals with special dietary needs. Now, however, healthy cuisine that contributes to well-being is becoming stamped in popular culture. Michael Pollan’s just-released “Food Rules: An Eater’s Manual” has been spotlighted on Oprah and in a New York Times article that appeared on the paper’s most e-mailed list for several days.

Enrollment at the Natural Gourmet Institute has increased by 15 percent for each of the past three years, bringing the current enrollment to 224 students. Enrollment at raw and vegan Living Light Culinary Arts Institute in the coastal Fort Bragg, Calif., went up 13 percent between 2008 and 2009, pushing the total enrollment to over 700 students. And, at the vegetarian Natural Epicurean Academy of Culinary Arts in Austin, Texas, e-mail and phone inquiries about the program have gone up by 30 percent over the past year, according to community relations coordinator Jamie Perkins.

The Natural Gourmet and other vegetarian and natural cooking academies are expanding their course offerings to reflect increased student demand. While the School of Natural Cookery in Boulder, Colo., has been open since 1983, it recently only began to substantially increase its course load. In October, it launched an online series of courses, with 200 videos — a collection founder Joanne Saltzman said is still growing. The “Main Course,” which is spread over four weeks, advises students on a range of food preparation, including basics such as “Sauces” to the less commonplace “Improvising Natural Desserts.”

“We believe that plant-based dishes are not up to par and need more training than animal food,” said Saltzman. “Some people assume that vegetarian food is simply food without meat, and this is not the case.”

Reflecting a growing demand for health-conscious personal chefs, the Natural Gourmet Institute will offer a course for entrepreneurial chefs in September, helping students develop their own businesses.

While most of the schools offer conventional classes such as “Knife Skills,” they also provide an insight not present in classic cooking academies: the relationship between food and disease prevention and treatment.

“We concentrate on the relationship between food and health,” said Natural Gourmet Institute Vice President Merle Brown, sitting in her office framed by books such as The Revolution Will Not Be Microwaved and Living Raw Food. “Most students are not looking to do restaurant work, but make a difference in the way that people eat.

At the Natural Gourmet Institute, classes such as “Food and the Immune System” and a “Food and Healing Lectures” series are part of the school’s core six-month curriculum. At the Natural Epicurean, students of the two-year program take “Fundamentals of Cooking for Disease Prevention,” learning the benefits of ingredients such as sea vegetables and natural sweeteners, while students at the School of Natural Cookery take courses such as “Energetic Nutrition.” The Living Light Culinary Arts Institute offers “The Science of Raw Food Nutrition” in order to help students learn about blood sugar and weight management.

“There’s a movement away from just solving health problems with standard American medicine,” said Karen Fraser, the student services manager at Living Light Culinary Arts Institute, which offers both chef certificates and workshops.

In recent years, Fraser has seen more students — and their clients — turn to raw and vegan food as part of their treatment plan for Type 2 diabetes, which most experts argue requires a diet low in fat and high in fiber.

In the past year, according to Fraser, more restaurants have been demanding the style of food preparation that the academy teaches — with many so-called “meateries” from large cities such as Los Angeles, San Francisco and New York sending one of their chefs to receive training that was once reserved for specialty restaurants. Fraser has also noticed more requests for healthful-cooking personal chefs.

Gabriele Riva, who manages the three Nobu Japanese restaurants in New York City and one in Los Angeles, enrolled in a raw food workshop at the Living Light Culinary Arts Institute in October in order to bolster his food preparation techniques.

“I was able to open up possibilities and see what I can do with more ingredients. I learned a lot,” said Riva, whose menu includes several vegetarian items.

Christy Morgan, a 2006 Natural Epicurean graduate and vegetarian personal chef in Los Angeles, said she’s seen a large increase in clients in the past six months.

“At most culinary schools, they just teach you techniques,” said Morgan, who also authors the popular “The Blissful Chef” blog. “I learned so much about the human body and physiology, and how food affects our minds and spirits.