By Glenn Concepcion

In a world grappling with a rising population, climate change, and a growing need for healthier food options, scientists are turning to an unlikely pairing: rice and seaweed. 

A scientific review published in Critical Reviews in Food Science and Nutrition explores the vast, untapped potential of combining rice starch with biopolymers from seaweed to create transformative products that benefit both human and planetary health. 

Rice is a staple food for more than half the global population, but a significant portion—over 15% of polished rice—consists of broken grains often sold for lower-value uses like animal feed. At the same time, seaweed production has skyrocketed, growing from just half a million wet tons in 1950 to nearly 36 million tons in 2020, thanks to its exceptional nutritional profile rich in fiber, vitamins, minerals, and antioxidants. 

Researchers at the International Rice Research Institute and the University of the Philippines-Diliman Marine Science Institute saw a powerful opportunity in these two resources. By extracting starch from underutilized broken rice grains and blending it with hydrocolloids—natural gelling agents like agar, alginate, and carrageenan from seaweed—they can create novel materials with remarkable properties. 

“Combining rice starch with seaweed biopolymers is not just a technical novelty,” the study’s authors state, “it reflects a strategic alignment of nutritional enhancement, material functionality, and environmental sustainability”. 

Food, nutrition, and health 

The review compiles extensive evidence showing how these blends can dramatically improve everyday foods. For example, adding seaweed-derived κ-carrageenan to rice-based products reduces cooking loss and creates a more palatable texture. In gluten-free breads and pastas, seaweed fortification significantly boosts dietary fiber and mineral content, offering healthier alternatives for consumers. 

The benefits extend to managing health conditions like diabetes and obesity. Seaweed polysaccharides have been shown to lower the glycemic response of starchy foods. Studies demonstrate that incorporating seaweed components can increase the amount of “resistant starch” (a beneficial fiber) in rice products, effectively lowering their predicted glycemic index. Other research found that consuming wakame seaweed with rice significantly reduced post-meal spikes in blood glucose and insulin levels. This makes rice-seaweed composites a promising avenue for developing foods that help manage blood sugar. 

Beyond direct food products, these blends are ideal for creating advanced food technologies. Scientists have developed edible films and coatings from rice starch and seaweed that can prolong the shelf life of fresh fruit, like plums, by reducing weight loss and maintaining firmness. The blends can also be used for microencapsulation, a process that enhances the bioavailability of bioactives, probiotics, and vitamins. Studies have shown that microcapsules made from a rice starch-alginate matrix improve the survival rate of beneficial probiotic bacteria in products like ice cream and yoghurt. 

Sustainable farming and products 

The synergy between rice and seaweed goes beyond the plate. It represents a unique opportunity to align agriculture, industry, and environmental sustainability under the globally recognized One Health framework, which emphasizes the interconnected health of people, animals, and ecosystems.  

Many of the world’s top rice and seaweed producers, including China, Indonesia, and the Philippines, are perfectly positioned to integrate these value chains. In fact, a previous study has shown that seaweed biopolymers can boost rice yields by up to 65 percent. Furthermore, while traditional rice farming can be a significant source of methane emissions, seaweed farming helps capture carbon, reduce ocean acidification, and enhance marine biodiversity. These ecological benefits also support fisheries and coastal livelihoods, creating a feedback loop that strengthens both environmental and human health.  

The industrial applications of rice–seaweed biopolymer blends are also wide-ranging. Biodegradable thermoplastics derived from rice starch and agar are being developed as sustainable alternatives to petroleum-based plastics. These materials have been successfully used in agricultural technologies, such as functional films and soil moisture sensors, which enhance water use efficiency and promote climate-smart farming practices. Integrating rice and seaweed systems reflects the core of the One Health approach. It enables a holistic strategy that addresses environmental conservation, public health, and economic sustainability through interconnected solutions. 

Looking to the future 

To unlock this potential, the review calls for investment across the entire value chain—from improving seaweed cultivation and post-harvest handling to standardizing extraction methods. Modern techniques like Integrated Multi-Trophic Aquaculture (IMTA), where different marine species are farmed together, have been shown to increase seaweed biomass and improve biopolymer quality. Similarly, advanced extraction methods using ultrasound or microwaves can boost the yield and functionality of seaweed hydrocolloids compared to traditional techniques. 

“To fully harness the potential of rice starch–seaweed biopolymer composites, targeted research must address several key gaps,” the authors conclude, highlighting the need for a deeper understanding of biochemical interactions and comprehensive life cycle assessments to confirm their environmental benefits. 

By upcycling a byproduct of the world’s most important grain and combining it with one of the planet’s most sustainable and nutritious resources, the fusion of rice and seaweed offers a powerful, innovative path toward a healthier and more resilient global food system. 

Published Date: October 20, 2025