Smooth or crunchy. Grape or strawberry. Crusts first or no crusts.

Want to start a food fight?

Ask two people how to make the perfect peanut butter sandwich, and they'll almost certainly disagree. Our PB&J opinions seem to be set in early childhood and resist all modification.

There are hundreds of subtle and not-so-subtle variations that have helped this sandwich acquire and maintain its status as one of the most popular American lunch items for the past 100 years -- and will likely be a staple in lunchboxes as students return to school this fall.

Curiously, peanut butter started out on its path to glory as a health food product, marketed by John Harvey Kellogg of breakfast cereal fame as an alternative to "cow's butter." Andrew F. Smith, who teaches food studies at the New School in New York City and is author of "Peanuts: The Illustrious History of the Goober Pea" (University of Illinois Press, 2002), explained how peanut butter made its relatively quick transformation from a vegetarian protein substitute to the popular food product it is today.

Mr. Kellogg, a medical doctor who advocated vegetarianism and started a cereal company with his brother, began marketing peanut butter in 1894. Within five years "it was everywhere," Mr. Smith said.

At first, peanut butter was much more savory than the average modern version, so it was probably only a matter of time before someone thought to pair it with jelly.

The earliest documented evidence for a peanut butter and jelly sandwich came from the November 1901 edition of the Boston Cooking School Magazine, which included an "original" recipe for finger sandwiches with "three very thin layers of bread and two fillings, one of peanut paste ... and currant or apple jelly for the other."

The recipe's stuffy tone is no accident. At first, peanut butter was a luxury ingredient. It required special equipment to produce it, so its consumption was mostly restricted to the upper- and upper-middle classes. But technology improved, and by the Great Depression peanut butter was cheap enough to serve as a protein source for those who couldn't afford meat. Thanks to the invention of sliced bread, even very small children could make their own peanut butter and jelly sandwiches.

Sometime along the way, manufacturers realized that the American public, especially children, preferred a sweetened peanut butter, along with their jelly, and began adding sugar or honey to their products. The rest, as they say, is culinary history.

For the record, Mr. Smith prefers his PB&Js with Smucker's grape jelly and crunchy peanut butter ("who wants smooth peanut butter?!" he asked, aghast). "For me it's nostalgia, it's my childhood. That's what my mom packed."

He's not alone. For several generations, peanut butter and jelly sandwiches were synonymous with childhood brown bag lunches. And they invariably bring back fond memories. But many of today's children have no such associations because the prevalence of life-threatening peanut allergies has led to a lockdown of sorts.

Mr. Smith believes that the peanut allergy issue first began to draw a lot of attention in the 1970s, although it's not clear whether allergies increased or simply people's awareness of them rose. According to the Asthma and Allergy Foundation of America, peanut allergies affect 2 percent of the population. This lifelong allergy is the most common cause of death attributed to foods. Reactions can be extremely violent with just a little exposure to the allergen. As a result, by the 1990s many schools had either banned peanuts entirely -- including peanut butter and jelly sandwiches -- or created peanut-free tables or lunchroom areas. Also banned or tightly regulated ("no nuts") at some schools were homemade snacks that parents baked for classroom parties.

Unable to live without this kid-friendly standby, parents have turned to other nut butters. Most have been around for as long as peanut butter, but due to their higher cost -- and some would say inferior flavor -- they have trailed far behind peanut butter in the national psyche.

Sunflower seed spread has become a relatively popular substitute, and SunGold Foods, maker of SunButter (www.sunbutter.com) has a number of recipe suggestions, including one for a sunflower butter, apple and turkey bacon sandwich.

Message boards for the popular food website chow.com were full of ideas for nut butter sandwiches, such as almond butter with apricot jam on sourdough, or almond butter, apple butter and sliced apples, with a sprinkle of cinnamon and a drizzle of honey.

For youngsters who can still bring the traditional sandwich for lunch, there's the added concern over whether they should. Nutritionists emphasize the importance of eating a varied diet. So, is the child who eats a peanut butter sandwich every single school day endangering his or her health?

No, according to UPMC sports nutritionist Leslie Bonci. If a child wants a peanut butter and jelly sandwich every day for lunch, she thinks that's just fine. In fact, she recalls that her younger child ate exactly that almost every day for lunch from kindergarten to 12th grade.

"It's far more important that the lunch actually gets into them," Ms. Bonci said.

Two tablespoons of peanut butter (a typical serving) translates to about 200 calories, with 8 grams of protein and 15 grams of fat (the "good" fat -- the monounsaturated that benefits heart health). A tablespoon of jelly adds about 50 calories. Peanut butter also is a filling food, taming hunger longer than other snacks.

Parents can try using whole wheat bread and an unsweetened peanut butter, but if the child throws out the sandwich, the added nutrition won't matter.

"This is just one food item in a whole day," she said. So parents should work to ensure their children eat a variety of foods, rather than focusing too much on a single item in a single meal.

The allergen cloud hanging over the national love of peanut butter may give the PB&J even greater nostalgic powers. Some cafes and casual restaurants put their own creative spin on it, such as the OTB Bicycle Cafe on the South Side. There the menu includes the Freerider, a triple-decker peanut butter and jelly sandwich -- with bacon.

The flavor combination is even more popular on dessert menus. This past spring, pastry chef Naomi Gallego included a peanut butter and jelly-inspired dessert on the opening menu at Habitat, the Downtown restaurant in the Fairmont Hotel. You can get a PB&J crepe at J'eet in Bloomfield, and a PB&J milkshake at the Milk Shake Factory on the South Side.

Oatmeal Peanut Butter and Jelly Muffins

PG tested

These muffins taste exactly like a great peanut butter and jelly sandwich, especially when warm. They're healthy enough for breakfast, but they'd also make a great lunch-box dessert or afternoon snack. -- China Millman

• 1 1/3 cups whole wheat pastry flour
• 1 cup quick-cooking oats (not instant)
• 1 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 1/4 cup brown sugar
• 1/4 cup sugar
• 1 egg
• 1/4 cup canola oil
• 1/3 cup peanut butter
• 1 1/4 cups reduced-fat buttermilk
• 1 teaspoon vanilla
• 12 teaspoons grape jam

Preheat oven to 375 degrees. Grease 12 muffin cups.

In a large bowl combine the flour, oats, baking powder, baking soda, salt and sugars. In a smaller bowl combine the egg, oil, peanut butter, buttermilk and vanilla.

Pour the egg mixture into the flour mixture and stir just until combined.

Fill each muffin cup 1/2 full and place 1 teaspoon of jam on top of batter. Place another scoop of batter over the top of jam. Fill muffin cups to nearly full.

Bake for 18-20 minutes. Place muffins on a baking rack to cool.

Makes 12 muffins.

-- By Kim Kautto who blogs at www.theungourmet.com

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