1966 — "Alice in Medicareland", Health News, Volume 43, Number 1:
He [Lewis Carroll] would be delighted with the news magazine, famous for its neologisms, which recently called a well-known culinary authority a gastronaut.
1969 — The New York Times Book Review, Volume 74 (ad copy):
And the ebullient wit of TV's top gastronaut keeps you cooking with laughs. It's a handsome gift, too — just $7.50 at book and department stores now.
1971 — Frederick S. Wildman, Jr., A Wine Tour of France: A Convivial Wine Guide & Travel Guide to French Vintages & Vineyards, Vintage Books (1976), ISBN9780394717555, page 67:
The intrepid gastronaut, in a day's motoring tour from Paris, can with luck and a strong constitution bracket his afternoon's visit to Chablis with at least two of them.
1995 — The Good Food Guide 1996 (ed. Jim Ainsworth), Which? Books (1995), ISBN9780852025857, page 71:
Time was when the keen gastronaut touching down in Sloane Square was hard-pressed to find anywhere in the immediate vicinity worth a second look.
1995 — Rowley Leigh, "Food & Drink Head for the Hills", The Guardian, 17 February 1996:
I had some moments of cold sweat on Boxing Day, as several very serious gastronauts sat in salivatory anticipation while my fonduta resolutely failed to thicken next door.
2005 — Daniel O'Connor, "Brillat-Savarin's Nineteenth-Century Proto-Atkins Diet: A Case Study in Inductive Inference", in The Atkins Diet and Philosophy: Chewing and the Fat with Kant and Nietzsche (eds. Lisa Heldke, Kerri Mommer, & Cynthia Pineo), Open Court (2005), ISBN9780812695847, page 57:
A longtime foodie and gastronaut, about a year after doing the Atkins Diet I found myself reading The Physiology of Taste (La Physiologie du gout) by Jean Anthelme Brillat-Savarin (1755-1826).
The mere words 'park café' are enough to make a gastronaut shudder, but your first visit to the Garden Café may change all that.
2009 — Jason Sheehan, Cooking Dirty: A Story of Life, Sex, Love and Death in the Kitchen, Farrar, Straus and Giroux (2009), ISBN9780374289218, page 46:
But then I would've also sworn that nothing in particular was driving me toward the so-called culinary arts either; nothing in my makeup or personal history that had me kinked as a sensualist, a gastronaut, a fucking foodie.
For confirmation, just think of the millions of people who, after watching Keith, were inspired to cook, eat, drink; to become a gastronaut and savour — truly relish — every morsel, every drop, every bloody bit of it!