Heirloom Rice for Sake Brewing – Historic Japanese Rice Strains  

What is heirloom Rice for Sake Brewing in Japan?

Currently (as of 2025), over 125 rice varieties are used in sake brewing. New rice strains have been emerging every year, with the goal of enhancing the quality of sake, particularly rice varieties that can better adapt to the increasing frequency and severity of extreme weather events caused by climate change. While experts in the sake industry are looking to develop new rice strains, some brewers have traced the crossbreeding history of rice and re-adopted heirloom rice for sake brewing.

Heirloom rice refers to traditional rice varieties that have evolved naturally and are not the result of human intervention. In the rice cultivation sphere of Asia, there are local heirloom rice varieties native to specific regions.  

Generally, a rice variety would be considered an heirloom variety when it satisfies these three conditions:  

1. Existed before modern breeding techniques  
2. Not genetic modified and engineered
3. Existed before the use of synthetic chemicals for harvesting, which were modern agricultural practices adopted since the 1950s  

Genetic research of rice in Japan is a relatively recent phenomenon. The history of crossbreeding rice varieties dates back around 100 years. Yamada Nishiki was officially registered in 1936, while Gohyakumangoku was registered in 1957.  Many of the famous sake-brewing rice strains were only developed or actively used in sake brewing after World War II.   

So, how about rice varieties used in sake brewing before the scientific approach to rice genetics and brewing chemistry? Sake breweries used whatever rice they could get in the rice market for sake brewing.  

Before the introduction of modern agricultural practices, Omachi (雄町) and Kameno-o (亀の尾) were the popular rice strains that people ate. Omachi and Kameno-o are the ancestral rice strains for many sake-brewing rice and table rice in Japan; for example, Yamada Nishiki and Gohyakumangoku are genetically derived from Omachi. At the same time, table rice varieties such as Sasanishiki (the dominant table rice used in sake brewing by breweries in Miyagi Prefecture) and Koshihikari (the top table rice by production volume) have genetic roots coming from Kameno-o.   

Both Omach and Kameno-o demonstrate exceptional qualities for sake brewing. In the Showa Period (1926-1989), there is even a saying that Omachi is the representative rice strain of Western Japan, while Kameno-o is the representative rice strain of Eastern Japan 「西の雄町」「東の亀の尾」.   

---

Uniqueness and Challenges

Different Asian countries have made efforts to preserve the culture of heirloom rice. The objective of these projects often falls into these categories:

1. Preserve the genetic diversity of rice cultivation
2. Revitalise the culture of community rice production and traditional farming practices
3. Offering medicinal and nutritional values
4. Food security (heirloom rice varieties are often hardier to pests and weather hazards)

For Japan, the revitalisation of heirloom rice varieties involves protecting the gene pool and enriching the culture of growing these varieties within the local ecosystem. To achieve this goal, actively using these heirloom rice varieties in sake brewing could ensure continuity of supply and, therefore, reliable production.

Moreover, as Japanese people more than a hundred years ago have already discovered: heirloom rice varieties make good sake! They contribute to a the unique regional styles of sake as, in blind tastings, the characteristics of these heirloom rice varieties often come through to the final style of sake. For sake made with Omachi, it often features a bold, earthy tone to its flavour and structure.  For sake made with Kameno-o, it offers a clean palate with sharp acidity in the finish. 

However, heirloom rice varieties are not so easy to grow. These varieties are often not compatible with modern agricultural methods like pesticides and fertiliser, which made them fall out of favour within farmers. For example, Omachi has a very tall stalk, measuring 160cm (compared to table rice varieties that are typically around 100cm tall), which makes Omachi prone to lodging. Feeding Omachi with more synthetic fertiliser would exacerbate the lodging situation.

Similarly, Kameno-o experiences vigorous growth if the rice plant is fed with synthetic fertilisers. Yet, if you farm the rice without synthetic fertilisers, the rice plant will develop deep roots to hold on to the soil, reducing the risk of lodging.

Nevertheless, heirloom rice varieties offer a storytelling element that connects the brewery to the consumer. For sake breweries, heirloom rice varieties provide an excellent opportunity for those who wish to recreate sake that was drunk a century ago (but usually with a modern touch). For consumers, they will be interested in how farmers and sake breweries overcome the obstacles and challenges in growing and brewing sake with these rice varieties.

Thus, one of the reasons why breweries would want to revive heirloom rice varieties and utilise them in sake making is that while these heirloom rice varieties are challenging to cultivate, it is a point of difference to allow breweries to differentiate themselves from one another. It is a selling point on its own. 

In the next blog post, we will delve further into the intriguing stories of Omachi and Kameno-o, as they deserve a spotlight on their own. 

---

Reference

Heirloom Rice from the Philippines – https://heirloomrice.com/

Food and Agriculture Organization of the United Nations (FAO) – https://www.fao.org/plant-treaty/areas-of-work/farmers-rights/inventory-on-frs/news-detail/zh/c/809936/ 

The Guardian – https://www.theguardian.com/environment/2017/sep/24/why-indias-farmers-want-to-conserve-indigenous-heirloom-rice

Minomaru Jozo – https://hinomaru-sake.com/item/junmai-mansaku-kamenoo70

JA 全農： https://www.zennoh.or.jp/oy/product/rice/omachi/ 

岡山県備前雄町：http://bizen-omachi.pref.okayama.jp/ 

和合の里を創る会、亀ノ尾の里資料館：https://www.wagounosato.jp/shiryokan/maboroshinokome