Sanuki udon: noodles, broth and ways to eat

Sanuki is the old provincial name for the area of today’s Kagawa Prefecture. Sanuki udon centres on wheat noodles made with water and salt, prized for elasticity and a smooth surface. It belongs to local household and shop traditions as well as to a name used in restaurants and packaged products across Japan. It is not a single soup recipe.

Salt water is first worked through the flour, breaking up wet clumps before the crumbs are brought together. Adequate hydration and mixing help gluten form a continuous structure. Salt changes the dough’s elasticity and extensibility, but adding more indefinitely does not improve it. Where foot pressing is used, the dough is folded and pressed repeatedly. Flour miller Yoshihara explains that folding changes its orientation, so pressure works the gluten structure in different directions. This follows bringing flour and water together and precedes rolling the sheet to its final thickness. A 1985 Kagawa survey recorded both shops that kneaded by hand without foot pressing and shops using machinery for part of the work.

Freshly mixed dough can resist rolling. During a covered rest, its structure relaxes, moisture becomes more evenly distributed and some trapped air escapes. It becomes easier to extend. This maturation is a dough-resting process rather than yeast leavening. Rolling aligns gluten in the direction of the applied force; turning the dough changes that direction. Sheet thickness and cutting width together determine the strand’s cross-section.

Temperature changes how the dough handles. Kagawa’s published Sanuki no Yume recipe uses more salt and less water in summer, when dough tends to become slack, and the reverse in winter, when it can become too stiff. Flour properties and the day’s conditions also affect mixing, resting and rolling. The aim is workable dough, rather than a saltier finished broth.

Boiling hydrates the strands and gelatinises their starch. Newly cooked noodles contain more moisture near the surface than at the centre. As they stand, water moves inward and the gradient diminishes; starch also changes during storage—a process called retrogradation—altering the texture. Eizo Miki’s 2006 account explains that a firmer aged noodle can nevertheless break more readily. Rinsing washes away surface starch and gives a different feel from unrinsed kamaage noodles.

Iriko—small dried fish, including the anchovies processed on Ibukijima—is a familiar stock ingredient. Kombu and bonito flakes can also be used. Stock extracts their flavour; soy sauce and other seasonings add saltiness and aroma. One Kagawa recipe prepares fish stock separately from kaeshi, a seasoning base of soy sauce, mirin and sugar, then combines them into concentrated dipping sauce. Its pouring broth uses more stock with light soy sauce. Locally, dashi can also mean the finished broth or dipping sauce.

Kake has noodles in a larger amount of seasoned broth. Bukkake uses a smaller amount of concentrated sauce poured over the noodles. Zaru serves water-rinsed noodles separately for dipping. Shōyu udon takes soy sauce or seasoned soy sauce directly. The liquid’s amount, strength and placement distinguish these forms more clearly than an added piece of tempura does.

Kamaage serves freshly boiled noodles in hot cooking water, with a separate dipping liquid. Kamatama combines hot noodles straight from the pot with raw egg and soy sauce or similar seasoning. Other dishes use noodles that have first been rinsed, served cool or reheated. Hot noodles are therefore not necessarily kamaage. In some shops, terms such as hiya-atsu name the noodle temperature first and the broth temperature second.

A conventional shop usually takes orders at the table and brings the noodles. Self-service shops use a counter where customers receive noodles and choose extras; some also let them reheat noodles or add broth. A noodle workshop may combine production and sales with on-site eating. Oden, rice balls and tempura are familiar extras. The exact self-service sequence varies, and customers are not generally cooking raw noodles from scratch.

Modern noodle production also developed through workshops. Ishimaru’s company chronology records dry-noodle production from 1904, water-powered milling from 1910 and closure of the milling division in 1966. In 1984 it commercialised dry noodles made by a process modelled on hand production. This case traces a move from milling and noodles together towards specialised manufacturing and new equipment. Dried products and freshly served noodles follow different production paths.

Before the war and into the early postwar years, household occasions remained important settings for making udon. Workshops then supplied cooked noodle portions to retailers, while general eateries served udon too. Specialised and self-service shops multiplied during the mid-twentieth century and after. A 1985 study already found machinery in most responding businesses. Changes in household labour, production and service together shaped the present eating landscape.

Hand-production demonstrations at Osaka Expo in 1970 helped raise awareness of Sanuki udon. Frozen products subsequently made it easier to prepare elsewhere. The Seto Ōhashi connection opened in 1988, improving access, while local magazine writing encouraged visits to individual shops. A 1993 book collected the celebrated Osorubeki Sanuki Udon series. Packaged noodles and trips to eat in Kagawa expanded alongside one another.

In the later twentieth century, prices, labour shortages and rain at harvest weakened Kagawa’s wheat production, while noodle making increasingly relied on imports. The prefectural experiment station began breeding in 1991 and applied to register Sanuki no Yume 2000 in 2000. It supplied a locally bred option developed for udon, but had weaknesses: relatively low yields, more difficult noodle processing than Australian Standard White wheat (ASW), and texture that deteriorated readily after cooking. These became targets for its successors.

Sanuki no Yume 2009 was selected through field trials, milling and noodle-making tests, and consumer tasting. Prefectural comparisons found higher yields and flour recovery than the 2000 cultivar, more gluten and a more supple noodle. The 2023 cultivar has stronger gluten and scored higher for firmness and viscoelasticity in the prefecture’s cooked-noodle evaluation. Yet its yield was lower than 2009 in the field comparison reported on that page. Breeding balances farming, processing and eating quality rather than improving every measure at once.

The product’s state determines what remains to be done. Fresh raw noodles have been mixed, shaped and cut but still need cooking. Dried noodles have had more water removed. Han-nama noodles are partially dried, retaining more moisture than dried noodles; the name does not mean half-cooked. Boiled noodles have already undergone starch gelatinisation. Cooking dried or han-nama noodles therefore differs from briefly reheating a cooked portion. Storage and heating instructions also depend on packaging, preservation and product design.

Sanuki udon now appears in everyday lunches, homes and celebrations, and circulates as dried, semi-dried and frozen noodles. An agriculture-ministry case study records Ishimaru’s dry-noodle exports to Taiwan through a trading company from 2002, followed by wider markets. That is one producer’s export route. The Agency for Cultural Affairs recognised Sanuki udon in its traditional 100-Year Foods programme for fiscal 2025, addressing a continuing food culture rather than one shop or a single menu.