Highlights: Researchers discovered that carrageenan stimulates the production of bifidobacteria. The substance is extracted from red algae and the bacteria benefit the intestinal microbiota. Discovery offers new raw material for prebiotic foods. A study jointly conducted by Embrapa Food Technology, the Federal University of the State of Rio de Janeiro (Unirio) and the State University of Campinas (Unicamp) found a new functionality present in carrageenan, which is extracted from red algae. It is capable of stimulating the production of bifidobacteria, microorganisms that are beneficial to the human gut microbiota. The process of developing the substance resulted in a patent being filed at the National Intellectual Property Institute (INPI) and the bifidogenic stimulus observed was higher than the ones already found in the market. The discovery paves the way for the development of new carrageenan-based prebiotic food products that promote benefits to intestinal activity. According to Brazil's National Cancer Institute (INCA) table of the estimated incidence of new cancer cases per primary location and sex in 2020, colorectal cancer was the third most frequent among men (7.9%) and the second among women (9.2%) in the country, which mirrors the estimates for their incidence around the world. For prevention, INCA recommends a diet rich in products that contain fibers, such as fruits, vegetables, whole cereals, beans and other legumes; and poor in ultraprocessed foods. Carrageenan is rich in food fibers and used to modify the texture of food products, as a thickening agent, and as a stabilizer to homogeneize them. On the other hand, it is not fully soluble in water and depends on high temperature for disaggregation and solubility. In order to overcome such challenge, the team of researchers used thermoplastic extrusion technology to make changes to the product. “The extrusion process was capable of promoting chemical changes to polysaccharid chains, affecting the physical properties of the carrageenan, modifying its solubility and apparent viscosity”, the Embrapa researcher Carlos Piler reports. Valuable aquatic raw material Rich in food fibers, vitamins, proteins, minerals, and antioxidants and with low energy content, seaweeds are widely used in Eastern cuisine. About 90% of their structure is composed of water, and the other 10% is composed of cell walls that have a gelatinous texture, give the algae malleability and protect them during the tide changes. It is from such gelatinous portion that the carrageenans and other raw materials with high added value for the food, cosmetic, pharmaceutical and agrochemical industries are extracted. The world's most cultivated seaweed is the red-colored species Kappaphycus alvarezii, grown for the extraction of carrageenan, a hydrocolloid which can be classified as a gum, often used in the food industry in dairy and meat products. Besides making carrageenan more soluble in water, the thermoplastic extrusion also increased its functional properties, observed Embrapa scientist Cristina Takeiti, who advised the research developed by Maria Eugênia Araújo Silva Oliveira at Unirio's Postgraduate Program on Food and Nutrition. “We found that carrageenan can be considered a natural source of dietary fiber of high nutritional value, capable of potentializing the bifidogenic effect of microorganisms in the human intestinal tract, working as a food supplement”, the researcher reveals. Seaweed as source of soluble dietary fiber According to the Global Guidelines of the World Gastroenterology Organisation (2017), a prebiotic is defined as an ingredient that results in specific changes in the gastrointestinal microbiota, thus conferring benefits upon host health. The study led by Embrapa assessed the prebiotic effect present in carrageenan after going through the extrusion process, and obtained promising results. “Even though only one bacterial strain of the Bifidobacterium species, Bb12, has been assessed in this study, the data indicates that carrageenan has bifidogenic activity in vitro. However, new studies with others strains have to be conducted”, asserts professor Maristela Nascimento, from Unicamp's College of Food Engineering Laboratory of Hygiene and Legislation, which performed the tests. The Bifidobacterium species Bb12 is one of most demanding in terms of growth in the gastrointestinal system because they need very specific conditions to increase in numbers inside the gut, hence the significance of the result obtained. The use of dietary fiber as a food supplement is regulated in the country by the Brazilian Health Regulatory Agency (Anvisa). Registering the product at Anvisa will take further research: in vitro simulation of human digestion, clinical toxicity, bioavailability and clinical trials. “It is still early days, but we have already obtained good pointers”, ponders the Unicamp professor. Seaweed cultivation According to global data from the Food and Agriculture Organization of the United Nations (FAO), in 2012 macroalgae represented 26% of the world production of cultivated organisms, totalling 23.8 million tons, at bout US$ 6.4 billion. The last data point that the average production of aquatic organisms, including seaweed, increased tenfold between the years of 1950 and 2015 in the world. Seaweed have been commercially explored as crops in different regions of the planet, representing an important source of income for riverside communities and small, mid-sized and large businesses. Currently, the world's top producers of seaweed and byproducts are Southeast Asian countries, such as the Philippines and Indonesia. In 2015, Brazil imported about two tons of carrageenan, extracted from Kappaphycus alvarezii algae, for its food industry, at the cost of over US$16 million. There is no official data on seaweed production in Brazil, but according to information from the Ministry of Development, Industry and Trade (MDIC) from 2016, the national production is not able to meed the demand for this product. Currently, the cultivation of the seaweed Kappaphycus alvarezii for commercial purposes in Brazil exists solely in sea farms by the coasts of the states of Rio de Janeiro and São Paulo, under authorization of the Brazilian Institute of Environment and Renewable Natural Resources (Ibama). Environmental licenses for experimental cultivations on the coasts of Paraíba and Santa Catarina have recently been issued as well. An innovative initiative in algaculture is the startup D’Alga Urban Aquaculture, which produces fresh and dehydrated seaweed of the Ulva fasciata species, popularly known as sea lettuce. The seaweed is cultivated in tanks through an aquacultural system that is integrated with fish farming and developed in salty water recirculation. Used in the whole world, this system allows the cultivation of a large amount of seaweed in a small space, optimizing the use of land, water and energy. This allows seaweed production to be possible in urban zones, for instance, without the need for environmental permits. For the oceanographer Beatriz Castelar, a visiting researcher of the Department of Veterinary Sciences of the University of Turim, and one of the partners of D'Alga, there is still a lot to advance in this sector in the country. She says that seaweed crops are incipient because there is not a culture of consuming seaweed or of producing raw material production for the industry. “In general, this production sector is still in a consolidation stage and suffers from bureaucratic problems to obtain cultivation licenses. To make algaculture a viable alternative source of income and effective employment, it will be necessary to establish public politcy to disseminate practices and promote legislation that facilitates the professionalization of the activity”, she assesses. On the other hand, she considers that it is an enormous field of research and development in the country, because the Brazilian coast extends through more than 7,000 kilometers. “We need a strategic plan for the development of the macroalgae food chain. It has an enormous potential for innovation and business. There is a lot to be researched, a lot to be done here in Brazil”, she concludes. Photo: D'alga Aquaculture Translation: Mariana Medeiros
| Highlights: -
Researchers discovered that carrageenan stimulates the production of bifidobacteria. -
The substance is extracted from red algae and the bacteria benefit the intestinal microbiota. -
Discovery offers new raw material for prebiotic foods. |
A study jointly conducted by Embrapa Food Technology, the Federal University of the State of Rio de Janeiro (Unirio) and the State University of Campinas (Unicamp) found a new functionality present in carrageenan, which is extracted from red algae. It is capable of stimulating the production of bifidobacteria, microorganisms that are beneficial to the human gut microbiota. The process of developing the substance resulted in a patent being filed at the National Intellectual Property Institute (INPI) and the bifidogenic stimulus observed was higher than the ones already found in the market.
The discovery paves the way for the development of new carrageenan-based prebiotic food products that promote benefits to intestinal activity. According to Brazil's National Cancer Institute (INCA) table of the estimated incidence of new cancer cases per primary location and sex in 2020, colorectal cancer was the third most frequent among men (7.9%) and the second among women (9.2%) in the country, which mirrors the estimates for their incidence around the world. For prevention, INCA recommends a diet rich in products that contain fibers, such as fruits, vegetables, whole cereals, beans and other legumes; and poor in ultraprocessed foods.
Carrageenan is rich in food fibers and used to modify the texture of food products, as a thickening agent, and as a stabilizer to homogeneize them. On the other hand, it is not fully soluble in water and depends on high temperature for disaggregation and solubility. In order to overcome such challenge, the team of researchers used thermoplastic extrusion technology to make changes to the product.
“The extrusion process was capable of promoting chemical changes to polysaccharid chains, affecting the physical properties of the carrageenan, modifying its solubility and apparent viscosity”, the Embrapa researcher Carlos Piler reports.
Valuable aquatic raw material Rich in food fibers, vitamins, proteins, minerals, and antioxidants and with low energy content, seaweeds are widely used in Eastern cuisine. About 90% of their structure is composed of water, and the other 10% is composed of cell walls that have a gelatinous texture, give the algae malleability and protect them during the tide changes. It is from such gelatinous portion that the carrageenans and other raw materials with high added value for the food, cosmetic, pharmaceutical and agrochemical industries are extracted. The world's most cultivated seaweed is the red-colored species Kappaphycus alvarezii, grown for the extraction of carrageenan, a hydrocolloid which can be classified as a gum, often used in the food industry in dairy and meat products. |
Besides making carrageenan more soluble in water, the thermoplastic extrusion also increased its functional properties, observed Embrapa scientist
Cristina Takeiti, who advised the research developed by Maria Eugênia Araújo Silva Oliveira at
Unirio's Postgraduate Program on Food and Nutrition. “We found that carrageenan can be considered a natural source of dietary fiber of high nutritional value, capable of potentializing the bifidogenic effect of microorganisms in the human intestinal tract, working as a food supplement”, the researcher reveals.
Seaweed as source of soluble dietary fiber
According to the Global Guidelines of the World Gastroenterology Organisation (2017), a prebiotic is defined as an ingredient that results in specific changes in the gastrointestinal microbiota, thus conferring benefits upon host health. The study led by Embrapa assessed the prebiotic effect present in carrageenan after going through the extrusion process, and obtained promising results.
“Even though only one bacterial strain of the Bifidobacterium species, Bb12, has been assessed in this study, the data indicates that carrageenan has bifidogenic activity in vitro. However, new studies with others strains have to be conducted”, asserts professor Maristela Nascimento, from Unicamp's College of Food Engineering Laboratory of Hygiene and Legislation, which performed the tests. The Bifidobacterium species Bb12 is one of most demanding in terms of growth in the gastrointestinal system because they need very specific conditions to increase in numbers inside the gut, hence the significance of the result obtained.
The use of dietary fiber as a food supplement is regulated in the country by the Brazilian Health Regulatory Agency (Anvisa). Registering the product at Anvisa will take further research: in vitro simulation of human digestion, clinical toxicity, bioavailability and clinical trials. “It is still early days, but we have already obtained good pointers”, ponders the Unicamp professor.
Seaweed cultivation
According to global data from the Food and Agriculture Organization of the United Nations (FAO), in 2012 macroalgae represented 26% of the world production of cultivated organisms, totalling 23.8 million tons, at bout US$ 6.4 billion. The last data point that the average production of aquatic organisms, including seaweed, increased tenfold between the years of 1950 and 2015 in the world.
Seaweed have been commercially explored as crops in different regions of the planet, representing an important source of income for riverside communities and small, mid-sized and large businesses.
Currently, the world's top producers of seaweed and byproducts are Southeast Asian countries, such as the Philippines and Indonesia. In 2015, Brazil imported about two tons of carrageenan, extracted from Kappaphycus alvarezii algae, for its food industry, at the cost of over US$16 million.
There is no official data on seaweed production in Brazil, but according to information from the Ministry of Development, Industry and Trade (MDIC) from 2016, the national production is not able to meed the demand for this product.
Currently, the cultivation of the seaweed Kappaphycus alvarezii for commercial purposes in Brazil exists solely in sea farms by the coasts of the states of Rio de Janeiro and São Paulo, under authorization of the Brazilian Institute of Environment and Renewable Natural Resources (Ibama). Environmental licenses for experimental cultivations on the coasts of Paraíba and Santa Catarina have recently been issued as well.
An innovative initiative in algaculture is the startup D’Alga Urban Aquaculture, which produces fresh and dehydrated seaweed of the Ulva fasciata species, popularly known as sea lettuce. The seaweed is cultivated in tanks through an aquacultural system that is integrated with fish farming and developed in salty water recirculation. Used in the whole world, this system allows the cultivation of a large amount of seaweed in a small space, optimizing the use of land, water and energy. This allows seaweed production to be possible in urban zones, for instance, without the need for environmental permits.
For the oceanographer Beatriz Castelar, a visiting researcher of the Department of Veterinary Sciences of the University of Turim, and one of the partners of D'Alga, there is still a lot to advance in this sector in the country. She says that seaweed crops are incipient because there is not a culture of consuming seaweed or of producing raw material production for the industry.
“In general, this production sector is still in a consolidation stage and suffers from bureaucratic problems to obtain cultivation licenses. To make algaculture a viable alternative source of income and effective employment, it will be necessary to establish public politcy to disseminate practices and promote legislation that facilitates the professionalization of the activity”, she assesses.
On the other hand, she considers that it is an enormous field of research and development in the country, because the Brazilian coast extends through more than 7,000 kilometers. “We need a strategic plan for the development of the macroalgae food chain. It has an enormous potential for innovation and business. There is a lot to be researched, a lot to be done here in Brazil”, she concludes.
Photo: D'alga Aquaculture
Translation: Mariana Medeiros 
