The pride of Tomakomai, Hokkaido — a brand pork raised with absolute dedication to the rich umami of fat and the highest standards of safety.
B1 Tonchan is a brand pork produced with integrated in-house management by Pork Island Onodera in Uetoi, Tomakomai City, Hokkaido. The name is inspired by Vitamin B1, which is richly abundant in pork. The defining feature of this brand is a thoroughly natural, antibiotic-free approach to health management. A proprietary feed incorporating lactic acid bacteria and edible charcoal supports healthy gut flora, aids digestion and absorption, and draws out the pigs’ natural immunity. In addition, a spacious rearing area of 3.6 square meters per pig — far exceeding the legally required standard — ensures that pigs can grow freely and without stress, contributing to superior meat quality. The feed incorporates approximately 15% locally-grown wheat, barley, and rice flour, adding a mellow, grain-derived sweetness and umami that give depth to the fat. The addition of 3% edible charcoal further suppresses unwanted off-odor, resulting in a clean and refined flavor. Shipping age is approximately 180 days, with the slow, patient fattening allowing the umami of the fat to accumulate fully. The breed is a three-breed cross — a female Landrace × Duroc first-generation cross sow with a Berkshire boar — delivering an exquisite balance of marbled lean and richly flavored fat. With annual shipments of approximately 300 head, the rarity is significant, and the brand can be experienced in charcoal-grilled butadon, pork buns, and hamburgers at ‘Plaisir,’ a producer-direct takeout corner inside Michi no Eki Utonai-ko. A uniquely characterful brand pork from Tomakomai, Hokkaido — one that pursues both the deliciousness of fat and food safety without compromise.
Basic Information
- Name
B1 Tonchan - Production Area
Uenae, Tomakomai City, Hokkaido - Management Body
Pork Island Onodera - Breed / Crossbreeding
Female (Landrace Female × Duroc Male) × Male Berkshire - Meat Characteristics
Gut health managed via lactic acid bacteria and edible charcoal, combined with 3.6 m² per pig — clean, fat-forward richness with minimal off-odor. - Feed Characteristics
Proprietary feed with approx. 15% local wheat, barley, and rice flour; lactic acid bacteria and 3% edible charcoal added to promote gut health and suppress off-odors. - Shipping Age
180 days - Annual Production
Approx. 300 head/year - Signature Dish
Charcoal-grilled butadon (pork rice bowl) / Pork bun / Hamburger (at Plaisir, Roadside Station Utonai-ko) - Certifications
Brand specifications established: April 11, 1992
Farm HACCP: In preparation - Related URLs
Pork Island Onodera (HPA)
Plaisir at Roadside Station Utonai-ko
Plaisir Official Blog (Ameblo) - Source
Brand Pork Guidebook 2026 p.23
HPA Hokkaido Pork Producers Association
Plaisir at Roadside Station Utonai-ko
Plaisir Official Blog
Last updated
June 19, 2026