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Udon Total Recycling Project

Powering an environmental program with local products



Kagawa Prefecture is so renowned for its udon noodles that it calls itself "the Udon Prefecture." Several years ago a local revitalization project found great success marketing udon, and many people from all over Japan came to Kagawa Prefecture to enjoy its noodles.

Now they not only eat udon in Kagawa, they've started recycling it. Kagawa's groundbreaking recycling system, which functions at a level where absolutely no udon is wasted, is drawing attention as a model for future food waste processing. We spoke about the project with Chiyoda Manufacturing CEO Eiji Iketsu, who single-handedly undertook the development of the hardware portion of what came to be known as the "Udon Total Recycling Project," and Tomio Sumada, president of the Udon Total Recycling Consortium.

"Before we started this project, the issue of disposable chopsticks came to our attention," Sumada says. "The chopsticks customers used in udon shops were all thrown away. An initiative was launched to collect the chopsticks and recycle them into wood pulp. Through that initiative, it came to light that there was also a large quantity of udon being thrown away."

To give an example, one company in Kagawa Prefecture that manufactures a great deal of frozen udon was disposing of approximately fifteen hundred tons of noodles per year at peak production, primarily because of defects in production. Under the recycling project, discarded udon is shredded and combined with enzymes, yeast and water to produce ethanol.

According to Iketsu and Sumada, there have been many attempts all over Japan to extract ethanol from various raw materials, but the amount collected has been small, so when factoring in labor and equipment costs it is rather difficult to continue. Udon is a starch, however, so it has the advantages of simple fermentation and the equipment needed being inexpensive. The ethanol extracted can then be used to boil udon.



"Udon made from udon," and "Boiling udon using udon-derived fuel," --The Udon Marugoto Junkan (Total Udon Cycle) Project


Kagawa Prefecture in Shikoku Island is very famous for udon noodles. Annual consumption of udon in Kagawa is 230 servings per person, which means that local people eat udon almost every day. The prefecture has over 800 udon noodle shops that serve Sanuki udon, specialty of the prefecture. People across Japan visit Kagawa to eat tasty udon.

Meanwhile, the volume of udon waste is huge. More than 3,000 tons of udon are discarded annually for various reasons; udon shop owners say, "Firm texture is vital for Sanuki udon, so we only serve udon for a period of time after it has been made, and because we don't want to make customers wait, we stockpile a certain amount, some of it goes to waste." and "Udon production at factories generates scraps."

In this article, we will introduce a major effort to build a system model for a sustainable recycling-based society by reducing waste at Sanuki udon shops by daily recycling discarded udon scraps into a circulating system instead of treating them as burdensome food waste.

Keiko Katsuura, representative of an environmental group called NPO Green Consumer Takamatsu, called for the involvement of NPOs, businesses, municipalities, and volunteers with the Total Udon Cycle Consortium, established in January 2012, with "mottainai (meaning "waste not, want not,")" as its catchword, signaling the start of this collaboration among government, industry, and other components of the public and private sectors.

Two major trends that helped lead to the establishment of this project were already under way: One was research by Chiyoda Manufacturing Co., an industrial equipment maker in Takamatsu City, which had since 2009 been undertaking research on using udon residue at frozen udon factories. It pursued this project jointly with the National Institute of Advanced Industrial Science and Technology (AIST) Shikoku, and the Food Research Branch of Kagawa Prefectural Industrial Technology Research Center. In 2011, they developed a plant that manufactures bioethanol from waste udon. After continuous improvement, the current plant was set up in 2012 with the assistance of the national government's New Energy and Industrial Technology Development Organization (NEDO). The plant consists of a bioethanol fermentation system, with a distillation column and methane fermentation tank, and a methane gas power generation system, with the capacity to produce 200 liters of bioethanol from 1,500 kilograms of waste udon.

The other was a project of Green Consumer Takamatsu for recycling disposable chopsticks used at udon noodle and other shops to create Japanese washi paper and particle board. Then, other NPOs, together with Takamatsu City, university professors, and volunteers, combined these trends to establish the Total Udon Cycle Consortium.


The project started to utilize discarded udon noodles as a resource material, with the aim of creating a new collaborative and recycling-oriented society. Through completely recycling waste udon and using it to manufacture biomass energy as an alternative of fossil fuels, it also contributes to the alleviation of global warming.

At first, they made bioethanol from the residue of udon noodles, and used the fuel for boiling the noodles. They cultivated spring onions used to garnish udon using liquid fertilizer made from udon-noodle waste. In July 2013, a year and a half after its establishment, the project went into its second phase, and developed the "Udon-Ken Sanuki Biofuel Power Project." (Kagawa prefecture is so thoroughly identified with udon that it officially calls itself "Udon-ken," literally "Udon Prefecture."). This project aimed to generate excess power with biogas made from waste noodles to help improve profitability.

Thus, "Udon made from udon," and "Boiling udon using udon-derived fuel," have become catchphrases that represent the whole circulating system based on the product life-cycle of udon, from "manufacturing bioethanol from udon residue to boil the noodles at noodle shops and generating electricity from biogas, to cultivating wheat with liquid fertilizer made from udon residue and making new udon with that flour."





The dregs remaining after ethanol extraction don't go to waste; they are processed in methane fermentation equipment to create methane gas. The methane gas is used as boiler fuel to keep the temperature of the aforementioned ethanol fermentation equipment stable.

"Even after we extract the ethanol and methane gas, we still have some dregs left over. These are made into liquid organic fertilizer using specialized equipment, and the fertilizer is scattered over the fields that grow the wheat used to produce the udon and the green onions eaten with the udon. Liquid fertilizer is bulky and difficult to store, so we're currently perfecting a process that will use special technology to make it solid."

Under this recycling system, nothing goes to waste. Sumada and Iketsu are eager to expand the program to food waste disposal in general.

"It's a paradigm shift: to go from using energy to dispose of waste to harvesting energy from waste. We're convinced that this system will play a useful role in ensuring a stable energy supply, but at present, when we consider the cost and risk involved in businesses starting these initiatives individually, there's a high threshold to overcome. We've been able to make it this far because of the cooperation we've gotten from the prefecture and the city. We believe that it's necessary to undertake this balancing act of gaining administrative support on both the soft and hard fronts, fostering business support, and changing popular attitudes to create an eco-friendly society that recycles its energy."

It is hoped that Kagawa's environmental program, which makes exhaustive use of local resources, will be promoted throughout Japan as an example of a cutting-edge success.


by Rieko Suzuki











One of the special advantages of the project is that various companies, NPOs, universities, and local governments are participating and working together to promote it. The main players and their roles are as follows:

  • Chiyoda Manufacturing Co. plays a central role in operating and managing the plants for bioethanol, biogas and liquid fertilizer.

  • Sanuki Mengyo Co., a company that owns udon manufacturing plants and shops, is in charge of collecting discarded udon noodles, separating waste, and providing udon noodle-making experience to participants of eco tours.

  • NPO Green Consumer Takamatsu carries out environmental education.

  • The executive committee of another NPO, Peace of New Earth, serves as the Consortium's secretariat while planning and managing the project.

  • Takamatsu City gives advice on waste management administration and hosts an event, "Stop Global Warming! Exhibition" to help the project, etc.

  • Kagawa Prefectural government officially joined the project in 2013. In fiscal 2014, it started to be fully engaged in promoting and providing information about the project in environmental education classes at schools throughout the prefecture, including creating DVDs and booklets, distributing them to all primary and secondary schools.

  • Volunteers

All the project members act in their respective areas of expertise. In addition to project members, farmers, welfare facilities, the prefectural agricultural experimental station, college professors and students lend a hand on various fronts.

To promote the project's popularity among people in Kagawa Prefecture, the Consortium focuses on information dissemination and educational activities through environmental and nutritional education in elementary and junior-high schools, for example by using liquid fertilizer made from the residue of waste udon noodles in school gardens, etc. It aims to offer such classes in most of the elementary and junior-high schools in the prefecture within the next three years time to foster awareness about conversion of food waste into energy, as well as how Kagawa's famous Sanuki udon noodles can be recycled into resources.

In reply to our questions about the difficulties of collaborating with a variety of players, Shinsuke Kume, president of Peace of New Earth and the head of the secretariat of the Udon Total Cycle Consortium, said "When we established the Consortium, at first we found it difficult to communicate the aims of the project to members and sometimes there were some gaps in understanding. But through our efforts to achieve consensus-building during steering committee meetings and working groups, we have achieved harmony. I think we have been quite successful in consensus-building so far, and one of the reasons why our current project is going smoothly is because we had already developed trusting relationships to some extent through former projects, such as the disposable wooden chopstick project, prior to launching the udon cycling project."

"In our project, players put their individual strengths to use. For example, companies play a part in 'udon power generation' and recycling of food waste, while NPOs and local governments focus on environmental education, farming, dietary education, and the fusion of Kagawa Prefecture's unique udon noodle culture and the environment," Kume says. It is clear that collaboration is a key to promoting this project widely among local people.

The number of people who visit Chiyoda Manufacturing's plant has increased to several hundred annually, and many others participate in eco tours that the project organizes. From fiscal 2014, it plans to organize eco tours collaborating with the Udon-Ken Electric Power Project for solar power generation as well as with local enterprises that are installing boiler facilities that use timber from tree plantation thinning, hoping to make Kagawa a mecca for the environment.

They hope to promote the Udon Total Cycle Project by installing some other plants in the prefecture to generate energy from food waste other than udon noodles in the future, and to share ideas among citizens in Kagawa such as "Udon is a resource -- a source of energy," and "Udon is an environment-friendly food," and "Kagawa is a leading prefecture in the area of environment." We look forward to further development of this project.


Written by Kazuko Iijima and Junko Edahiro

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