Carrying the blood of black pork and Duroc — a Saitama brand pork of finely-grained texture and a sweetness that overflows with every bite.
Marble Big, carefully raised at the self-operated direct farm of Koyano Specialty Meat Shop Co., Ltd. in Gyoda City, Saitama Prefecture, is a cross of Berkshire (black pig) female with Duroc male — the greatest appeal of this brand being the drawing out of the advantages of both breeds. Berkshire is the representative black pig, known for its finely-grained meat quality and high fat quality. Duroc, on the other hand, is characterized by rapid growth and marbling-style fat — with a well-established reputation for rich sashi and soft meat quality. Through the crossing of these two breeds, Marble Big is finished as a pork of elegant, sweet fat harmonized with a firm yet moist texture. There is also a thoroughgoing commitment to the rearing approach. In the late stage of rearing, the dedicated Sakitama Kurobuta feed compound by Japan Nosan Kogyo Cooperative is given, with a patient rearing period of 210–240 days of age through to shipment. Shipping weight is approximately 110–120 kg — raised slightly larger than standard fattening pigs, firmly drawing out the thickness and umami of the meat. Particularly noteworthy is the absence of antibiotics in all feed. The producer’s sincere stance toward food safety supports the quality of each individual animal. Annual shipments are extremely limited at 50 head — a brand pork of high rarity value. Wholesaling is handled directly by Koyano Specialty Meat Shop, with integrated management from production through to sales delivering fresh, reliable pork. Compatible with any typical Japanese pork preparation — from tonkatsu and ginger pork stir-fry to shabu-shabu — though for fully enjoying the sweetness of the ingredient, simple salt-grilling or steamed preparations are recommended.
Basic Information
- Name
Marble Big - Production Area
Koyano Seinikuten Co., Ltd. (Gyoda City, Saitama) — company-owned farm - Management Body
N/A - Breed / Crossbreeding
Two-breed cross: Female Berkshire x Male Duroc - Meat Characteristics
Refined sweetness from Berkshire heritage combined with Duroc marbling; moist, firm-yet-pliant texture with minimal gaminess - Feed Characteristics
Finishing period: Saitama Kurobuta dedicated feed (Nippon Nosan Kogyo Cooperative formulation); entirely antibiotic-free throughout all stages - Shipping Age
210-240 days / 110-120 kg - Annual Production
50 head annually (direct wholesale by Koyano Butcher). Extremely rare. - Signature Dish
N/A - Certifications
Farm HACCP: not applicable
Trademark: not registered
Designated retailer program in place
All feed is antibiotic-free - Related URLs
Koyano Seinikuten Official Site - Source
Branded Pork Guidebook 2026, p.94
Koyano Seinikuten Official Site
Last updated
6/21/2026