90 Day Dry Aged Prime Rib | Japanese A5 Miyazaki-Gyu

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Learn about how we label beef and wagyu grading standards.

Indulge in the pinnacle of Japanese craftsmanship with this extraordinary Miyazaki-Gyu A5 Prime Rib, meticulously dry-aged for 90 days to unlock unparalleled depth of flavor. Sourced exclusively from the award-winning Miyazaki Prefecture, home to Japan’s most celebrated Wagyu cattle, this cut exemplifies the highest level of marbling (BMS 10–12), melting tenderness, and a rich, buttery mouthfeel.

During its three-month dry-aging process, the prime rib undergoes a transformative journey—concentrating its umami essence, developing nutty, earthy undertones, and achieving a texture that is simultaneously delicate and luscious. The result is an ultra-luxurious eating experience that combines the natural sweetness of authentic Miyazaki-Gyu with the bold, sophisticated complexity that only extended dry aging can provide.

Ideal for the true connoisseur, this showstopping centerpiece is perfect for a refined dinner or an unforgettable celebration. Best enjoyed simply seasoned and slow-roasted to medium-rare perfection, it pairs beautifully with a bold red wine or fine sake.

• Origin: Miyazaki Prefecture, Japan

• Grade: A5 Miyazaki-Gyu (Wagyu Olympics winner)

• Marbling: BMS 10–12 (exceptional)

• Aging: Dry aged for 90 days for unmatched flavor complexity

• Flavor Profile: Intense umami, subtle nuttiness, buttery finish

This is more than just a prime rib—it’s a culinary masterpiece reserved for the most discerning palates.

 

About A5 Wagyu Beef

A5 beef is measured on five factors: (1) marbling, (2) meat color and brightness, (3) firmness and texture of meat, and (4) color, luster and quality of fat.

In the quality grade, the lowest score from the four items of the yield grade is adopted. In other words, even if grade 5 was given to marbling, color and brightness, and firmness and texture, and only fat assessments was grade 4, the quality grade of this beef is classified as grade 4. Quality grading is severely done.

A5 means this beef excels in every single factor.It has a gorgeous webbing of fat that will make you feel a creamy mouth-feel in each bite. Its literally like tasting a cloud... a cloud of beef.

About Our Dry Aged Prime Rib Steaks

Dry aging takes time, a keen eye for quality and a precise technique for the perfect ripening climate. We have it. A proper dry-aged steak is expensive and usually found at only the best steakhouses. These steaks are FUNKY and will be SMELLY. As steaks are dry aged they lose moisture as evaporation occurs and natural enzymes change the steak. This produces a strong umami flavor and the breakdown of carbohydrates produces a sweetish taste. A lot of purveyors are selling 30 day dry aged steaks where the funk is noticeable. These steaks are VERY dry aged. The funk will be strong.

This steak has been dry aged for at-least 45 days, but usually for 55-65 days.

Learn more about our dry aging process here.

What Makes Our Dry Aged Prime Rib Best In Class?

You do not have to look hard enough to find cheaper Prime Rib. But the devil is in the details. Meat N' Bone carries USDA Prime or Choice but more importantly G1 Certified, Angus Prime Rib wet aged for anywhere between 30-45 days.

You will not only get the beef marbling that comes with the grade of Prime, but you are eating premium beef from Angus steers ("A" maturity), fed with premium grain and pasture. These are steers that weight less than 1,050 lbs. This is "the good stuff" raised and processed in America, aged and cut in Chicago.

It's important to note that marbling is not a driving indicator of tenderness and hence, not all beef that's graded 'Prime' is equal. Learn more about steak marbling here.

 

THE MIYAZAKI-GYU DIFFERENCE

At Meat N' Bone we made the conscious decision of selling not only Miyazaki A5 but Miyazaki Gyu because it is the best in the world. Other Wagyu from the area that do not meet the criteria for Miyazakigyu must be sold as "Miyazaki Kensan Gyu" or "Beef from Miyazaki Prefecture."

All Miyazakigyu is Wagyu but not all Wagyu is Miyazakigyu. Miyazakigyu is one step above Miyazaki Wagyu and is the cream of the crop of all Wagyu from Miyazaki. It is quite literally the best beef in the world.

All five years, national “Wagyu Olympics” are being held to determine Japan’s, and therefore the world’s, best Wagyu. In September 2017, the Miyazaki-gyu was ranked 1st. for the third time in a consecutive row, this being a first in Japanese history and therefore rightfully enabled to use the title “Best Wagyu in the World”.

You can and will find cheaper A5 beef. In fact, even Kobe beef is cheaper. But we chose to offer the best beef in the world at the most affordable price that we could.

 

Best Cooked: Medium-Rare, Medium, Medium-Well

We carry an extensive lineup of Prime Rib cuts including different, breeds, sizes and even dry-aged options.