F1 Kozatsu

Japanese F1 Wagyu — kōzatsu (交雑種), the Japanese term for a first-generation crossbreed. Japanese Black sired over dairy stock, raised and graded in Japan. Cleaner texture, more approachable richness, unmistakably Japanese. Currently from Kaneko Farm in Aomori and the Rokko program.

Frequently Asked Questions

What is Kozatsu Wagyu?

Kozatsu (交雑種, kōzatsu) is the Japanese term for crossbred beef — not a farm or a region. It refers to a first-generation cross of a Japanese Black (Kuroge) sire over dairy cattle, raised in Japan. Japan classifies its beef in three categories: Wagyu (fullblood), kōzatsu (F1 crossbred), and dairy breed.

What does F1 mean in Wagyu?

F1 designates a first-generation crossbreed — one Wagyu parent crossed with another breed. Japanese F1 crosses Japanese Black over dairy cattle. Australian F1 means roughly 50% Japanese genetics crossed with Angus or similar. They are distinct products despite sharing the F1 label.

Is Japanese F1 the same as A5 Wagyu?

No. F1 is crossbred and is legally not Wagyu in Japan, where the term is reserved for fullblood cattle. F1 carcasses are still graded on the same A1 to A5 scale and typically land at A3 with a Beef Marbling Score of 6 to 7.

How does Japanese F1 compare to A5 Wagyu?

A5 is dramatically more marbled and richer. F1 is leaner with cleaner beef flavor and a firmer texture, which means you can eat a full portion rather than a 4-ounce tasting serving. It suits grilling, reverse searing, and larger cuts better than A5 does.

Read the full Kozatsu guide →