Something wasn’t quite right about the chicken soup.

The team at Manischewitz had gathered in the test kitchen at the company’s headquarters in Bayonne, N.J., last year to taste the latest version of one of their new offerings. But it wasn’t hitting the notes they were aiming for.

“We were tasting it against our grandparents’ and saying, ‘No, that’s not it; it’s just not like our Friday night chicken soup,’” said Shani Seidman, the chief marketing officer for Kayco, which owns Manischewitz.

More vegetables. More chicken. A little salt.

“A lot of times you think of improvement and innovation as extra or modern,” Ms. Seidman said in an interview this month. “But we’re going back to go forward.”

And chicken soup is only the start of it. Would your bubbe like a side of merch with that gefilte fish?

Manischewitz, the 136-year-old brand that has been a staple in American Jewish households for generations, is looking to go beyond Passover, which begins on Monday evening, with a top-to-bottom rebranding and an expansion of its product range.

Cans are out. Resealable bags are in. New products include grapeseed oil; frozen, gluten-free knishes and frozen matzo balls (don’t tell your mother!).

There is a new brand identity, with a color palette that leans heavily on the company’s signature orange, meant to evoke the appearance of its matzo ball soup. It includes a custom typeface with Hebrew-inspired details, Yiddishisms (“There’s bupkis like it!”) and whimsical doodled characters, reminiscent of Jewish cookbooks and prayer books from the 1950s, that are meant to invite everyone into the tent.

The idea, Ms. Seidman said, is not just to target “culturally curious” gourmands. It is also an attempt to tee up a new generation of hosts: millennials.

“When you host someone, you want to give them wholesome foods, things that you would cook,” she said. “We want to provide the next generation of consumers food they’d be proud to serve.”

In doing so, Manischewitz faces the difficult balancing act of preserving its legacy as a trusted brand and the most recognizable name in Jewish food, while dusting off a reputation that even its top executives acknowledge had become, well, dusty.

Amanda Dell, the vice president of programs and communications at the Jewish Food Society, said that many Jews connect to their cultural identity through the meals they share with their families. “My hope,” she added, “is that this rebrand can instill a new sense of pride in Jewish food.”

From Humble Beginnings to a Household Name

Manischewitz was founded in 1888 by Rabbi Dov Behr Manischewitz, a Prussian immigrant who scaled a small matzo bakery in Cincinnati into a large, standardized operation with a gas-fired oven and mechanized conveyor belt system. Manischewitz became a household name among American Jews and, by 1990, when the company was sold to a private equity firm, it controlled 80 percent of the matzo market in the United States.

Kayco, whose holdings include Sabra, Fox’s U-Bet and Kedem, is among the largest kosher food distributors in the United States. When it bought Manischewitz in 2019, it was seen in the kosher world as the equivalent of General Motors acquiring Ford.

“To us, we always looked up to Manischewitz as this legacy brand which had so much history in it,” said Charles Herzog, the president of Kayco, which was founded in 1848.

Mordy Herzog, the chief executive officer of Kayco and Royal Wine, felt that the Manischewitz brand “kind of drifted” under its previous owners.

“Their philosophy always was to modernize the brand, to make it more appealing to American consumers,” he said. “We want to do the same thing, but our way of doing it is by doubling down on who we are.”

To revamp its look, Manischewitz turned to Jones Knowles Ritchie, a branding agency that led redesigns for other legacy companies, including Dunkin’ and Budweiser.

JKR convened focus groups, consulted culinary experts and combed the Manischewitz archives. They decided to lean into, and amplify, the orange color that had been a staple of Manischewitz’s packaging for decades, said Lisa Smith, JKR’s global executive creative director. Phonetic spellings (“laat-kuh”) were added to the packaging to welcome new consumers.

The rebranding also includes a new series of drawn characters, including a family gathering around a dinner table and a figure hugging a cup of soup, that are meant to evoke illustrations from The New Yorker, she said. They have been featured on billboards in New York City and on digital screens in its subway system.

Jake Cohen, a Jewish cookbook author, was struck by Manischewitz’s new look during a recent visit to Whole Foods, comparing it favorably to other kosher brands that he said suffered from “an aesthetic that is so old.”

“The rebrand fit in so much better with the rest of the aesthetic of the average grocery store,” he said, “versus old-school Manischewitz branding, which looked like it belonged in a D’Agostino’s.”

At Manischewitz, there was a recognition that kosher food as a category was “generally in decline” even as consumers were showing more curiosity about different types of food and experiences, Ms. Smith said.

“It feels the cultural tailwinds that are happening seem to be aligning with the right time” for a new look and approach, she said.

Still, it was vital to keep the essence of the brand, Ms. Smith said.

“You can’t make something trendy and cater just to specific up-and-coming generations,” she said. Instead, she said, JKR and Manischewitz focused on “savoring our traditions” and “pausing to appreciate and pay attention to the food.”

That meant leaving some things as they were. Recipes for core items like matzo, gefilte fish and borscht will remain the same.

“If it worked for 130 years, it would be ridiculous to change it,” Charles Herzog said.

(Another thing Manischewitz won’t be touching is Manischewitz wine, which the company doesn’t make. It has licensed its name to a separate wine manufacturer since shortly after the repeal of Prohibition.)

The team at Manischewitz doesn’t have to look far for feedback. Their focus groups are sitting at their dinner tables.

“What we eat on Sabbath is what we sell,” Mr. Herzog said. “If we know that the matzo doesn’t taste good, it’s not from a study, it’s at the table.”

Beyond Passover, Mr. Herzog said the focus will be on expanding the company’s reach to emphasize that Manischewitz is not just a kosher brand, but also a Jewish food brand whose products can be enjoyed by anyone year-round. Think franks and blanks (a take on pigs in a blanket, but with beef) for the Super Bowl, mini potato puffs and cheese blintzes as a passed appetizer, or babka and (frozen) challah at brunch.

Manischewitz will roll out a new line of soups — chicken, tomato and vegetable — this summer, before the fall Jewish holidays. Manischewitz, which makes its matzo in Israel, will make the soups in a new factory it has built there.

“It’s opening the gates,” Mr. Herzog said. “You don’t have to be Jewish to enjoy a good bowl of chicken soup. You don’t have to be Jewish to enjoy matzo balls.”