Every so often I find myself reflecting on how things used to be or how things have changed since I was younger. These are thoughts I swore I would never have, much less describe aloud. But then I got older and, well, things changed.

They’ve also become much more convenient. While we may have given up something when we switched as a culture from preparing meals predominantly with fresh foods to packaged and frozen foods, we definitely have gained in some ways, too.

In my youth, if I wanted popcorn I had to put kernels and cooking oil in a large covered saucepan and slide the pan back and forth over a hot burner on the stove. Now I simply toss a package in the microwave for four minutes.

Pizza is another food item that has proliferated in the past few decades and changed the way people eat. I have a vivid memory from the early 1960s of my older brother covered with flour, trying to make a pizza from a Chef Boyardee pizza kit. Whatever frozen pizzas were available then were like cardboard, and people didn’t eat them as a first choice. Now making a pizza by hand is something reserved for foodies who are trying to dress down a meal.

I’ve spent a lot of time in this column disparaging packaged and precooked foods and encouraging people to cook fresh. I’m not backing away from that position, but I do want to acknowledge how far out in left field I am.

In the United States in 2006, a consumer would not be considered abnormal for eating nothing but food and beverages that had been flash-frozen. This might have been possible 50 years ago, but no one would have been interested. By contrast, most of the frozen food in supermarkets today is of reasonable quality.

Certainly, the amount of linear feet devoted to frozen inventory has expanded such that the retail portion of frozen food sales generates revenues in the tens of billions annually. Frozen food sales to the food-service industry are twice as lucrative.

These little factoids are from the American Frozen Food Institute, an industry organization that lobbies Congress and operates an informative, if self-important, Web site at www.affi.com.

The frozen-food industry traces its story to none other than Clarence Birdseye, who in 1923 invented a flash-freezing process that involved pressurized air, ice and brine. Six years later he sold his patents to a company that later would become General Foods, and the rest is frozen-food history.

The Clarence Birdseye story is hilariously recounted in about.com’s entries on inventors: “A taxidermist by trade, but a chef at heart, Clarence Birdseye wished his family could have fresh food all year.” Now that’s appetizing.

The AFFI Web site also offers a timeline of frozen food history. Clearly, the invention of the microwave oven in the 1960s was a turning point in frozen food sales. Before then, every frozen product had to be baked or boiled.

Among other historic frozen-food moments on the AFFI’s 1960s timeline was the following: “Frozen food sales soar when astronauts, upon return from landing on the moon, eat prepared frozen entrees and side dishes.”

Now that’s rough. These people had been in orbit for days, eating whatever passed for space food, and all they got when they returned to Earth was a 1960s-quality TV dinner.

What’s more, they probably had to wash it down with Tang, the powdered orange drink of the 1960s that was marketed as the astronaut’s beverage of choice.

But there I go, showing my age again.