Tag Archives: Vietnam

New technologies make cassava processing more efficient and sustainable

As the global cassava industry continues to grow, new processing technologies are helping factories to reduce energy losses.

The farming and post-harvest processing of cassava is a major economic activity throughout much of South-East Asia, Africa and Latin America.

In Africa and Latin America, cassava is a staple food for 500 million people and is increasingly processed into ready-to-cook or ready-to-eat products. Demand for these foods is rising as a result of changing expectations by growing middle-class consumers and urban populations.

In South-East Asia cassava processing for starch in particular is a major market driver, with Thailand being the world’s largest exporter of cassava products, including starch and chips.

In many countries, the processing of cassava takes place in small- and medium-scale factories where process inefficiencies, in particular energy losses, are significant and impact on both production costs and the environment.

Considering the high potential for growth of the cassava industry, driven by growing populations and economic development, it is critical to optimize cassava processing technologies to ensure the industry progresses in a sustainable manner.

Cassava processing for starch in Vietnam. Photo by G. Smith/CIAT

Cassava processing for starch in Vietnam. Photo: G. Smith/CIAT

To improve cassava processing technologies, the CGIAR Research Program on Roots, Tubers and Bananas (RTB) conducted a benchmarking study of cassava starch and flour technologies in several countries, as part of the larger 2013-2015 project “Driving livelihood improvements through demand-oriented interventions for competitive production and processing of roots, tubers and bananas”.

The study was conducted by a team from the International Center for Tropical Agriculture, the International Institute for Tropical Agriculture and CIRAD with support from Univalle and Clayuca in Colombia, Kasetsart University and KMUTT in Thailand, and Thai Nguyen University in Vietnam.

Findings confirmed that artificial drying of cassava is faster than sun drying and hence a key factor to increase the production capacity of factories. However, research shows that artificial drying represents 70-75% of the total energy used by a typical cassava starch factory, making it a key area to focus on improving energy efficiencies.

‘Flash drying’, the most suitable type of drying for cassava starch and flours, is efficient at large-scales, with 80-90% energy efficiency. However, at small-scales (less than 50 tons of product per day) where the majority of cassava processing occurs, energy efficiency is only 40-60% due to inadequate dryer designs.

Sun drying, as seen here in Vietnam, is less commonly used in favor of artificial 'flash drying'. Photo N.Palmer/CIAT

Sun drying, as seen here in Vietnam, is less commonly used in favor of artificial ‘flash drying’. Photo: N.Palmer/CIAT

To develop improved drying technologies to make the process more efficient and environmentally sustainable, the project launched a subsequent study using computer-based simulations of the flash drying operation that proved such improvements to small-scale dryers are possible.

A numerical model of flash drying to simulate and compare the drying process at small and large scales was developed, followed by methods to determine the optimum dimensions and operating conditions of flash dryers for different production capacities.

Critically, this led to the development of guidelines to design energy-efficient flash dryers that can help cassava factories or equipment manufacturers reduce their energy losses.

These innovations are now available to interested stakeholders in the cassava processing industry worldwide.

To share findings from the project with key stakeholders from the private and public sector, including cassava processing factories, equipment manufacturers, universities and government agencies, a workshop was held in Bangkok, Thailand from 2 – 4 December, 2015.

The workshop brought together participants from countries including Thailand, Vietnam, Myanmar, Indonesia, Philippines, Colombia, Nigeria, Tanzania, France and Germany, providing a valuable opportunity for networking and planning future collaborations on the development of the cassava industry.

Processed snack foods made using cassava starch. Photo: G.Smith/CIAT

Processed snack foods made using cassava starch. Photo: G.Smith/CIAT

The event was organized by CIRAD, Kasetsart University and Biotec, with financial support from RTB, SEA-EU-NET and the Embassy of France in Thailand.

The dissemination of the project’s findings will continue through capacity building events in other regions (Latin America, Africa) and the design and construction of a prototype flash dryer based on the newly developed guidelines for energy efficiency.

Read more

Learn more about the outcomes of the workshop and the project in the workshop report.

Access the project’s research findings and numerical models in the recently published (July 2016) paper, ‘Pneumatic Drying of Cassava Starch: Numerical Analysis and Guidelines for the Design of Efficient Small-Scale Dryers‘, published in the journal, Drying Technology: An International Journal.

Enabling gender equality in agricultural and environmental innovation

Through the global study ‘GENNOVATE: Enabling gender equality in agricultural and environmental innovation’, roughly 6,000 rural study participants of different ages and socio-economic backgrounds are reflecting on and comparing local women’s and men’s expected roles and behaviors — or gender norms— and how these social rules affect their ability to access, adopt, adapt and benefit from innovations in agricultural and natural resource management (NRM).

Central to the qualitative field study is an exploration of women’s and men’s agency – understood as “the ability to define one’s goals and act upon them” (Kabeer 1999, 438) – at the core of which is the capacity to make important decisions pertaining to one’s life. For rural women and men, these decisions relate to agriculture and NRM, as well as to other significant events in the private (household) and public (community) spheres. Such instances include, for instance, whether or not to pursue a given livelihood strategy or whether, with whom and when to start a family.


Men and women work together on a farm in East Africa. Photo by N.Palmer/CIAT

Among the Thai in Northwest Vietnam, “Men are the pillar of the family” is a common refrain. In the course of the GENNOVATE data collection, women and men from different age and socio-economic groups explained that Thai men are the ultimate decision-makers when it comes to important household decisions. Yet, unpacking how decision-making processes transpire showed a more nuanced picture, as women’s input into men’s decisions came to the fore. Both women and men described women’s at times successful attempts to persuade their husband to follow a particular course of action as well as the role of other household members in influencing decision-making instances. Yet, within that space for negotiation, it remained that when there is contestation, men will likely have the final say.

A family in Northwest Vietnam. Photo by Marlene Elias/Bioversity International

A family in Northwest Vietnam. Photo by Marlene Elias/Bioversity International

As a middle-aged woman explained in a focus group context, deciding how to spend her own inheritance “would not be difficult if I know how to persuade [my husband].” Likewise, a middle-income man described how, with respect to sales of home garden products, “Both the husband and wife will discuss with each other to come to an agreement. If both the husband and wife cannot come to an agreement, the husband will be the one who makes the final decisions and the wife has to follow his decision.” Another male focus group member later added, about how decisions should be made to spend a man’s own inheritance, “If my wife does not agree and I still do it anyway, both will have conflicts.”

Similar results in other case study sites suggest that decision-making processes may not be as clear cut as frequently described in the literature on gender and agriculture. A global analysis of the data will yield further insight into this critical dimension of social organisation and gender equality, and into whether or how this process plays out in different cultural contexts. More importantly, understanding how gendered decision-making processes occur will help to identify spaces wherein women can be supported to gain agency with respect to agriculture, NRM and in other significant areas of life; and where transformation towards more gender-equitable societies can occur.

‘GENNOVATE: Enabling gender equality in agricultural and environmental innovation’ is a cross-CRP, global comparative research initiative which addresses the question of how gender norms and agency influence men, women and youth to adopt innovation in agriculture and natural resource management.

The CGIAR Research Program on Roots, Tubers and Bananas is one of 11 CGIAR Research Programs participating in GENNOVATE, and is making significant contributions to gathering and analyzing qualitative research, particularly in relation to root, tuber and banana crops.

Read the original post, written by Marlène Elias, Gender Specialist at Bioversity International on the CGIAR Gender website.

Addressing postharvest losses in cassava value chains

Postharvest losses are an important challenge in developing countries, and the RTB Research Program has included the issue in its research agenda for improving food security and income-generating activities. Diego Naziri, a scientist seconded by the Natural Resources Institute (NRI) to the International Potato Center (CIP), works on the RTB team dedicated to promoting postharvest technologies, value chains and market opportunities. He is the lead author of a recently published article on “The diversity of postharvest losses in cassava value chains in selected developing countries,” which compares the situations of different cassava–producing countries such as Ghana, Nigeria, Thailand and Vietnam.

“This research is the result of the effort of a multi-disciplinary team,” Naziri explained. ““I was very surprised by the findings of this systematic assessment of postharvest losses for such a perishable crop as cassava. The extent of these losses, their type and the stages of the value chain where they occur differ so much from country to country. It is clear that there is no “silver bullet,” so before designing any intervention for postharvest losses reduction, I would recommend similar approaches in other countries and value chains.”

The full PDF text is available from the Journal of Agriculture and Rural Development in the Tropics and Subtropics: http://www.jarts.info/index.php/jarts/article/view/2014121946902/821


The extent of physical and economic postharvest losses at different stages of cassava value chains has been estimated in four countries that differ considerably in the way cassava is cultivated, processed and consumed and in the relationships and linkages among the value chain actors. Ghana incurs by far the highest losses because a high proportion of roots reach the consumers in the fresh form. Most losses occur at the last stage of the value chain. In Nigeria and Vietnam processors incur most of the losses while in Thailand most losses occur during harvesting. Poorer countries incur higher losses despite their capacity to absorb sub-standard products (therefore transforming part of the physical losses into economic losses) and less strict buyer standards. In monetary terms the impact of losses is particularly severe in Ghana and estimated at about half a billion US dollar per annum while in the other countries it is at the most about USD 50 million. This comparison shows that there are no “one-size-fits-all” solutions for addressing postharvest losses but rather these must be tailor-made to the specific characteristics of the different value chains.


Cassava in Vietnam / Credit: Dominique Dufour

Roots, Tubers and Bananas postharvest processing project gets started in Asia

Site selection is underway as the Roots, Tubers and Bananas (RTB) Postharvest Processing project on adding value under the RTB research program gets started. Entitled “Driving livelihood improvements through demand-oriented interventions for competitive production and processing of RTBs,” CIAT-Asia’s focus will be on improving livestock feeding with residues and wastes at small and medium-scale cassava processing enterprises in northern Viet Nam and eastern Cambodia.

“We are now in the process of identifying processors in those areas and selecting sites,” said CIAT Asia’s Keith Fahrney, who has been busy visiting starch extraction equipment makers and small-scale wet starch processors in Viet Nam, accompanied to Duong Lieu Commune, Hoai Duc District in November by CIAT’s Dominique Dufour, and Thierry Tran of CIRAD.

In addition to crop management research with partners in areas supplying processing enterprises, the project will also provide support to hire a cassava breeder in Asia in 2014 together with equipment for the molecular breeding lab at the Agricultural Genetics Institute (AGI) in Hanoi.

RTB CIAT field trip_2

From left to right: Nguyen Khac Quynh, Vietnam Academy of Agriculture Sciences (VAAS), Hoaiduc, Hanoi.
Thierry Tran, CIRAD-Qualisud, Kasetsart University, Bangkok, Thailand.
Le Than Mai, Department of Food Technology, Hanoi University of Science and Technology (HUST).
Dominique Dufour, CIRAD-Qualisud, CIAT, Cali, Colombia.
Son Chu Ky, Department of Food Technology, Hanoi University of Science and Technology (HUST).
Keith Farnhey, CIAT in Asia, Agricultural Genetics Institute, Hanoi.