The world's largest cruise ship spends $1 million a week on groceries. Here's how 30,000 meals a day are made to feed hungry passengers.

• More than 6,600 passengers board can travel on Royal Caribbean's Symphony of the Seas.
• Some passengers eat up to eight times per day, meaning kitchen staff need to prepare meals at all hours.

The world's largest cruise ship shells out more than 30,000 meals a day for over 6,600 passengers who board each week.

Passengers aboard the Royal Caribbean Symphony of the Seas cruise ship may eat anywhere up to eight times a day — giving the staff a hefty load of food options to produce.

"You have to calculate that is breakfast, lunch, and dinner, plus snacks, plus at night, plus all 24 hours, food all around, and that never stops," Allan Gentile, development chef of Culinary Innovation, told Insider. "The quantity is crazy."

Jaret de Silva, the ship's inventory manager, has a $1 million grocery budget each week to stock up the ship's 23 restaurants. that usually results in 30 trucks with 500 pallets worth of inventory, equating to more than 600,000 pounds of food and drinks, brought to the ship in the Miami port on a weekly basis.

Kitchens on the ship operate nonstop and are comprised of a culinary team of more than 1,000 people who cook for the guests while the boat is continuously moved by waves.

"Some of the people start to work at 8 o'clock in the morning all the way to 2 o'clock, take a break, come back at 5 p.m., feeding by 9:30 p.m. Then another group, I start to work at 10 p.m. to all the way to 10 o'clock in the morning. So we cover day or night production," German Eladio Rijo, the executive chef, told Insider.

At the bottom of the ship, there are prep kitchens — including the butcher, veggie cutting room, and fish-thawing box — where food items are assembled. From the prep kitchens, food is then moved to the main galleys before being cooked and served to patrons.

"We separate all the stores to the different locations that they are supposed to go. We have about 20 different storerooms, divided into, like, freezers, fridges, walk-in fridges, and dry stores," de Silva said. "So any delay in our operation can hamper the sailaway of the ship. It's a big logistic requirement."

There are 36 kitchens, also known as "galleys," on the ship. Twelve of them are specialty restaurants. And across each of them, there are approximately 100 different menus each week developed at Royal Caribbean's Miami headquarters.

"Any food on board this beautiful ship, anything you eat, it is my responsibility. Whenever you have beautiful potato fries, it's mine, rice is mine, pastry is mine. Salad, shrimp. Whatever you eat. It is my responsibility," Rijo said.

The restaurants cater to all different price points, to match the ship's wide range of passengers.

"We had the penthouse, we had the suite, we had the main restaurant, we had a specialty restaurant. We have all the choices. So we tried to please everybody, to make sure everybody finds what they're looking for. You need to have organization in the kitchen. So this all comes with experience to work in the cruise line," said Rijo.