The cause was complications from Alzheimer's disease, said her step-daughter Bronwyn Dunne.
Mrs. Jones helped open a world of cuisines to a public previously bound by convenience foods, and her impact on cookbook publishing, home cooking and the American palate was monumental.
Beginning in the 1950s, she followed her own curiosity and her instincts for what readers wanted to cook and needed to know, and she championed the work of unknown authors who became icons and whose books became classics.
The list of these scholar-cooks who owe her their career includes Madhur Jaffrey, Claudia Roden, Marcella Hazan, Joan Nathan, Edna Lewis, Lidia Bastianich, Anna Thomas, Hiroko Shimbo, Michael Field and Nina Simonds. She also edited some of Alfred A. Knopf Inc.'s most famous fiction writers, including John Updike and Anne Tyler.
Without her discovery of Frank's memoir, while she was at Doubleday in Paris, American readers might never have been introduced to Frank's startling, first-person narrative, one of the first Holocaust accounts to reach the United States. Her role was small but pivotal, and it was enough to get her noticed — and hired — by Knopf co-founder Blanche Knopf in 1957.
As a junior editor at Knopf, Mrs. Jones began primarily as a translator of such French writers as Jean-Paul Sartre and Albert Camus, and she had no intention of editing cookbooks, the work for which she became famous.
But she had fallen in love with French food when she lived in Paris after college, and upon returning to the United States with a new husband, she was desperate for help unlocking the cuisine's secrets in their New York kitchen.
One day in 1959, a huge manuscript arrived on her desk. "From the moment I started turning the pages, I was bouleversée, as the French say — knocked out," she wrote in her memoir, "The Tenth Muse" (2007). "This was the book I'd been searching for."
This was also the book that Child, with co-authors Simone Beck and Louisette Bertholle, had spent six years unsuccessfully trying to shorten for an editor at Houghton Mifflin. Child worried that the book "was unpublishable," she wrote in her own memoir, "My Life in France." "Maybe the editors were right. After all, there probably weren't many people like me who liked to fuss around in the kitchen."
Fortunately for Child — and for generations of cooks who fell in love with her — there was at least one who did: Mrs. Jones, who spent months trying recipes before deciding the book must see the light of day.
"If the book was so right for me, there were bound to be maybe thousands like me who really wanted to learn the whys and wherefores of good French cooking," she wrote. "Ordinary Americans, not just the privileged, were traveling to Europe now, in droves, and their taste buds had been awakened. I hoped we'd had our fill of quick-and-easy, and there was an appetite for the real thing."
She prevailed, and as Child's editor, Mrs. Jones got her hands, and kitchen, dirty. She scouted for ingredients and equipment, practiced making omelettes and "fluting" mushrooms, and gave recipes to a cooking neophyte in the Knopf office to try — all to make sure the recipes would work in American kitchens. She even was responsible for the book's title, "Mastering the Art of French Cooking."
"When I triumphantly showed our title to Mr. Knopf, he scowled and said, 'Well, I'll eat my hat if that title sells,' " she wrote. "I like to think of all the hats he had to eat."
'We are flying blind'
The diminutive Mrs. Jones, known for her classic suits and pageboy haircut, was also good at getting her authors noticed. When "Mastering" was nearing publication, she sent copies to taste-makers James Beard and Craig Claiborne, the latter the food editor of the New York Times.
They both loved it. Beard threw a party for Child & Co., and Claiborne agreed to review it — but only if Mrs. Jones and her husband, Evan, would first agree to be the subjects of a Times story about their own cooking.
"Mastering" sold millions of copies, and Child — who had emerged from her co-authors as the book's guiding force — became a TV star, culinary treasure and household name.
Mrs. Jones formed similar partnerships with other authors, having particular success with those writing about global cuisines curious to Americans.
"With a new, exotic, unfamiliar style of cooking, more than ever we are flying blind — we may never even have tasted the dish we are trying to reproduce — and we need a lot of hand-holding," she wrote. "So I kept my eyes and ears, to say nothing of my taste buds, open to the kind of writer-cook who was particularly gifted, like Julia, at explaining the techniques of a different cooking culture."
The best ones, she found, were often transplants, longing to re-create the foods of their homeland. That describes Hazan, whose passion for cooking didn't emerge until she and her husband had moved to the United States from Italy.
She and Hazan clashed often, with Hazan insisting on authenticity and Mrs. Jones wanting recipes to be accessible.
Mrs. Jones also developed a longstanding interest in regional American cuisine. After she was referred to Lewis, the granddaughter of a former slave who wanted to write a book about Southern cooking, Mrs. Jones was disappointed when sample pages Lewis wrote with a co-author didn't have Lewis's voice.
The co-author quit, and Mrs. Jones and Lewis instead began regularly meeting to talk about Lewis's upbringing in a small Virginia community founded by freed slaves. "While we were both still giddy with the pleasures she had evoked and the ease with which the details of each anecdote had surfaced, I suggested she go home right away and put everything down just as she had told it to me," Mrs. Jones wrote. "It worked miraculously." The stories and recipes in 1976 became "The Taste of Country Cooking," which served to transform the public's perception of Southern food and is still considered a masterpiece.
Nathan, the eminent Jewish-cooking authority, worked on four books with Mrs. Jones and traveled with her to Israel while working on "The Foods of Israel Today."
"She only wanted to do books that made a difference," Nathan said in an interview. "She's a real editor. There aren't many of them left."
Her favorite lesson from Mrs. Jones: "Find your voice," Nathan said. "Find who you are and don't be afraid to show it."
'We have to publish this book'
Judith Bailey was born on March 10, 1924, in New York City, where she was raised on Depression-era and wartime cooking. Her mother banned such vulgarities as garlic and onions (and even forbade the discussion of food at the table), but Judith took refuge in the kitchen of her family's hired cook.
"She came from Barbados and at my urging would tell me about the foods she grew up on — strange fruits I'd never heard of, hot peppers that made one sweat, and, of course, garlic," she wrote in her memoir. Her father recognized her adventurous palate and indulged her on restaurant visits.
After she graduated in 1945 from Bennington College in Vermont, she returned briefly to New York to work in publishing before a three-week vacation in Europe turned into a full-time move to Paris.
At 27, working as a "girl Friday" at Doubleday in Paris, she was tasked one day in 1950 with filing rejected submissions.
"My boss went off to lunch with his fellow editors, and left me with a pile of stuff," she told the Jewish Chronicle in 2009. "I came to this lovely face," she said, referring to Anne Frank's photo on the advance copy of the French edition of the book. "I read it all day. When my boss returned, I told him, 'We have to publish this book.' He said, 'What? That book by that kid?' "
It had been published in Dutch and was set for publication in French, but was rejected by other English-language publishers, too, before she successfully argued that the New York office of Doubleday should take it on. The story of the Holocaust as seen through a young girl's eyes became an international sensation, one of the best-selling books of all time and adapted for stage and screen.
Early in her Paris years, the future cookbook editor had been an assistant to Evan Jones, who edited a magazine aimed at American tourists. They wed in 1951, eventually settling in New York and maintaining their summer home in Vermont.
Survivors include four stepchildren, Bronwyn Dunne of South Burlington, Vt., Pamela Richards of Stamford, Conn., Audrey Bierman of Grinnell, Iowa, and John Christopher Vandercook of Honolulu; five grandchildren; and seven great-grandchildren.
In addition to her cookbook editing, Mrs. Jones wrote three books with Evan: "The Book of Bread"; "Knead It, Punch It, Bake It!" (a children's book); and "The Book of New New England Cookery."
She worked at Knopf for a half-century, but her early time there was not without struggle.
"For many years, she and Blanche were the only women in the Knopf offices," Sara Franklin, who spent months interviewing Mrs. Jones for an oral history on behalf of the Julia Child Foundation, wrote in Cherry Bombe magazine in 2014. "While editing prestigious writers helped Jones climb the ranks, her culinary pursuits were often perceived as fluff. Women were kept down, she remembers, and people often assumed she was a secretary rather than an editor."
In 2006, Mrs. Jones was awarded the James Beard Foundation's Lifetime Achievement Award. She retired from Knopf in 2010 as senior editor and vice president.
Her husband died in 1996, but Mrs. Jones was determined to not let his absence deter her from continuing their favorite ritual: cooking. "Instead of walking into what might have seemed an empty apartment — actually, I've always had a dog who is hungry to greet me — I gravitate toward the kitchen," she wrote in "The Tenth Muse."
After her memoir was published, Mrs. Jones received so many requests to write more about her solo cooking that in 2010 she published "The Pleasures of Cooking for One." Rather than dwell on the challenges, the book praises the joys of lighting a candle, pouring a glass of wine and laying out her best linens for a meal she would savor. She drew on a lifetime of cooking and lessons from the authors she had edited to espouse her belief in frugality and the smart use of leftovers, repurposing them into other dishes.
Her last book was 2014's "Love Me, Feed Me," a guide to making food that a cook could share with a dog. It's no accident that many of the recipes she wrote about doling out for herself and her little pooch, Mabon — Moroccan moussaka, Indian red lentils, Southern-style shrimp and grits — are staples of some of the same cuisines Mrs. Jones had long before helped demystify.
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