Researchers from the University of Tokyo in Japan have developed a technique through which it is possible to produce cement from food waste. Besides being used in construction, the innovative initiative is edible as well. You can make boiled cement into a delicious meal by adjusting flavors, adding seasonings, and breaking it into pieces.
Yuya Sakai, the professor responsible for the study, is an engineer specializing in concrete and recycling. In previous research, he developed a technique for mixing recycled concrete powder and wood waste, generating a more resistant material through hot compression. It was during these trials that the idea arose to test other waste materials similarly, including – why not – vegetables and fruits.
The production of this material is divided into three stages: after breaking the raw materials (orange peels, onions, pumpkins, bananas, Chinese cabbage and seaweed), the small pieces were placed in an oven at 105°C or a vacuum drying machine. Then, the dry materials were pulverized using a regular blender. Subsequently, the powder was mixed with water and seasonings and finally hot pressed at 180°C.
The tests were carried out considering the strength of the materials and also their taste. In this sense, the results indicated that, except for the pumpkin-derived sample, all the others reached the flexural strength goal, especially Chinese cabbage, which is three times more resistant than regular cement. According to the authors Sakai and Machida, the most challenging part of the process was the fact that each food requires different temperatures and pressure levels, which makes it possible to imagine how many tests had to be done before reaching a homogeneous and satisfactory result.
However, it was precisely this fine-tuning of the two conditions that made the experience successful since food waste had already been tested for cement production in other studies. It always required the addition of plastic to the mixture for the materials to agglutinate, but in this case, with optimal adjustment of temperature and pressure, this was not necessary.
The tests indicated that, despite the whole process, the food still retains its original scents and, according to Sakai, the product is non-toxic and safe for consumption but “is very crunchy”, as he says. It is also worth mentioning the material color since the original color of the food is also maintained, generating a wide range of combinations and possibilities.
Tests related to the material durability indicated that after four months of exposure in a room, there were no reports of insect, worm or fungal attacks. Furthermore, her appearance has remained the same. However, to ensure greater durability – despite losing its edible potential – this cement can be waterproofed with a chemical substance or coated with lacquer.
While the technology is still in the development phase to be applied in construction, many companies in other areas have sought out inventors interested in producing furniture and objects. In addition to the advantages, edible cement is biodegradable and can be buried when it is no longer useful, becoming a promising material for replacing products made with plastic and regular cement. Its application also adds a new meaning to architecture that, besides vision, touch, smell and hearing, can now also stimulate taste.
