Dig Japan vol.14 “Castella (カステラ)”

Castella (カステラ) is wagashi that allegedly originated in Nagasaki Prefecture and was developed uniquely based on the nanbangashi (南蛮菓子) introduced from Portugal. Typically, the batter is poured into a large square or rectangular mold, baked in the oven, and then cut into rectangles; the starch syrup gives it a moist texture. Nowadays, castella is sold in a variety of flavors, including cheese, vanilla, chocolate, and matcha, and castella scraps are often packaged in bags or wrapped in plastic wrap, and sold at a lower price than the original product.

Shoodo's castella (Photography via Shoodo)

Generally, the name “castella” is said to be derived from Portuguese “Bolo de Castela” which means ‘sweets of the Kingdom of Castile’ existed on the Iberian Peninsula. We can also find a description explaining the name “casteilla (kasteira)” in a document published in 1704, first year of the Hoei era. Regarding the origin of castella itself, there are two theories: one theory is that it comes from a Spanish baked confectionery “bizcocho” and the other is that it comes from the Portuguese cake “pão de ló.” Biscocho's origin is said to come from the word "baked twice" and it was originally something like hardtack. However, according to a Spanish dictionary published in 1611, there was another delicious type of biscocho made from flour, eggs, and sugar at the time.

The history of castella in Japan dates back to 16th century when the Portuguese reached Nagasaki Prefecture, then the only Japanese port open for foreign commerce, and started trade and missionary work. According to Kawakita Onzan's “Harajo Kiji (原城紀事)” written in 1846, one of the sweets made by missionaries in Hizen Karatsu in 1557 (Koji 3) was castella. “Harajo Kiji” was written by quoting “Yaso Tenchuki (耶蘇天誅記)” written in the middle of the Edo period. There are other documents that mention castella, for example, Oze Hōan's “Taikoki (太閤記)” written in 1626, which described that missionaries served castella and other nanbangashi during missionary work.

Shoodo's Matcha-castella (Photography via Shoodo)

Although there is no clear historical record of the person who was the first to bake castella in Japan, there are several candidates. For exapmle, Luis de Almeida, a missionary who established a hospital in Bungo and fed the sick with milk and beef as nourishment, and Toan Murayama who served nanban (European) cuisine and sweets to Hideyoshi in 1592. We can find a description of castella recipe under the name “kastehouji (かすてほう路)” in the cookbook “Nanban Ryorisho (南蛮料理書)” which is believed to have been written around 1600. 

During the Edo period, records regarding castella were achieved in Nagoya in 1644 and in Kyoto in 1681, and in the mid-Edo period, the Tokugawa shogunate presented castella as wagashi at Edo Castle to entertain imperial envoys. Improvements were made to the charcoal pot for baking castella, and by the mid-Edo period, something close to the prototype of the current Nagasaki castella was being made. The use of starch syrup, a characteristic of Nagasaki castella, is said to have started in western Japan after the Meiji period, giving it its current moist texture. In western Japan, it seems that the original pound cake-like, light texture was not preferred.

Shoodo's Gosan'yaki-castella (Photography via Shoodo)

The castella recipe was published in many confectionery and cookbooks during the Edo period, and was often served at tea ceremonies. On the other hand, because castella uses highly nutritious ingredients such as eggs, flour, and sugar, it was also used as a kind of nutritional supplement for wasting diseases such as tuberculosis from the Edo period to the prewar period. In modern times, the use of starch syrup has become widespread, giving it the flavour typical of Japanese sweets, and the use of gas ovens and electric kettles has made it easier and more stable to bake castella. It is presumed that these improvements led to it spreading throughout the country, and that it became popular with the general public through mass production after World War II.

In 1939, official price system for food and daily necessities began and the price of castella was also fixed across the country, however, since it only specified the price per weight and did not consider taste or quality, the quality of castella declined. For this reason, standards were established for castella from September 15, 1941: using at least the same amount of eggs and sugar, 55% flour, 20% starch syrup which can be honey or glucose, no leavening agents, and a thickness of at least 1 sun 6 bu, 5 mm.

This article was written by 𝐡𝐢𝐫𝐨𝐤𝐨, working as a freelance translator and press for overseas apparel brands in Japan, with the purpose of broadening her insight into the Japanese traditional culture.