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Tag: nutritional quality

The science behind the perfect bread and pasta flour

Have you ever considered that bread and pasta are made from different types of wheat? How about the fact that there are thousands of different wheat products consumed around the world, and each one has unique characteristics and processing requirements?

Scientists at the International Maize and Wheat Improvement Center (CIMMYT) understand that the quality of the final product, be it spaghetti, a loaf of sourdough bread or a tandoori naan, is highly dependent on the quality of the grain and the flour it becomes. Every year, CIMMYT analyzes thousands of wheat lines in detail at its Wheat Quality laboratory to determine the nutritional, processing and end-use quality of the grain. In this short video, CIMMYT’s Wheat Quality lab head Maria Itria Ibba explains exactly what they are looking for and how they find it.

First, CIMMYT scientists test the overall grain quality by analyzing grain weight, density, protein content, moisture content and hardness.

The grains are then milled into flour, which is again analyzed for moisture content, protein content, color and protein quality. Protein quality is especially important to determine the end-use for the type of flour, and CIMMYT conducts several tests to determine this characteristic. Bread and durum wheat flours specifically are analyzed for overall protein quality by checking SDS-sedimentation volume. Mixographs are used to assess the flour’s mixing and absorption characteristics, and alveographs are used to measure dough deformation properties.

At the end of the tests, bread wheat flours are transformed into leavened breads and scored based on the loaf’s volume and crumb quality. Durum wheat flour, used to make Italian-style pasta, is scored based on grain quality, flour yellowness, high protein content and protein quality.

CIMMYT’s work ensures that wheat-derived foods produced in developing countries are nutritious, affordable, and maximize profits for each actor in the value chain.

Cover photo: At CIMMYT’s Wheat Quality lab, researchers evaluate how different bread wheat varieties behave at the time of baking. (Photo: CIMMYT)

What is nixtamalization?

For centuries, people across Mexico and Central America have been using a traditional method, known as nixtamalization, to process their maize.

Now carried out both at household and industrial levels, this technique offers a range of nutritional and processing benefits. It could easily be adopted by farmers and consumers in other parts of the world.

What is nixtamalization?

Nixtamalization is a traditional maize preparation process in which dried kernels are cooked and steeped in an alkaline solution, usually water and food-grade lime (calcium hydroxide).

After that, the maize is drained and rinsed to remove the outer kernel cover (pericarp) and milled to produce dough that forms the base of numerous food products, including tortillas and tamales.

How does it work?

Key steps of the traditional nixtamalization process. (Graphic: Nancy Valtierra/CIMMYT)
Key steps of the traditional nixtamalization process. (Graphic: Nancy Valtierra/CIMMYT)

What happens when maize kernels are nixtamalized?

The cooking (heat treatment) and steeping in the alkaline solution induce changes in the kernel structure, chemical composition, functional properties and nutritional value.

For example, the removal of the pericarp leads to a reduction in soluble fiber, while the lime cooking process leads to an increase in calcium content. The process also leads to partial starch gelatinization, partial protein denaturation — in which proteins present in the kernel become insoluble — and a partial decrease in phytic acid.

What are the benefits of processing maize in this way?

In addition to altering the smell, flavor and color of maize products, nixtamalization provides several nutritional benefits including:

  • Increased bioavailability of vitamin B3 niacin, which reduces the risk of pellagra disease
  • Increased calcium intake, due to its absorption by the kernels during the steeping process
  • Increased resistant starch content in food products, which serves as a source of dietary fiber
  • Significantly reduced presence of mycotoxins such as fumonisins and aflatoxins
  • Increased bioavailability of iron, which decreases the risk of anemia

These nutritional and health benefits are especially important in areas where maize is the dietary staple and the risk of aflatoxins is high, as removal of the pericarp is thought to help reduce aflatoxin contamination levels in maize kernels by up to 60% when a load is not highly contaminated.

Additionally, nixtamalization helps to control microbiological activity and thus increases the shelf life of processed maize food products, which generates income and market opportunities for agricultural communities in non-industrialized areas.

Where did the practice originate?

The word itself comes from the Aztec language Nahuatl, in which the word nextli means ashes and tamali means unformed maize dough.

Populations in Mexico and Central America have used this traditional maize processing method for centuries. Although heat treatments and soaking periods may vary between communities, the overall process remains largely unchanged.

Today nixtamalized flour is also produced industrially and it is estimated that more than 300 food products commonly consumed in Mexico alone are derived from nixtamalized maize.

Can farmers and consumers in other regions benefit from nixtamalization?

Nixtamalization can certainly be adapted and adopted by all consumers of maize, bringing nutritional benefits particularly to those living in areas with low dietary diversity.

Additionally, the partial removal of the pericarp can contribute to reduced intake of mycotoxins. Aflatoxin contamination is a problem in maize producing regions across the world, with countries as diverse as China, Guatemala and Kenya all suffering heavy maize production losses as a result. While training farmers in grain drying and storage techniques has a significant impact on reducing post-harvest losses, nixtamalization technology could also have the potential to prevent toxin contamination and significantly increase food safety when used appropriately.

If adapted, modern nixtamalization technology could also help increase the diversity of uses for maize in food products that combine other food sources like vegetables.

Cover photo: Guatemalan corn tortillas. (Photo: Marco Verch, CC BY 2.0 DE)

Starting with Seeds

Seeds are the start and the first step in a solution for global hunger.

B.M. Prasanna, director of the Global Maize Program and of the CGIAR Research program on Maize at the International Maize and Wheat Improvement Center (CIMMYT), says smallholder farms in sub-Saharan Africa make up 80% of all farms there, and contribute significantly to food production in the region.

“Over the past 15 years, CIMMYT and partners in sub-Saharan Africa have been able to intensively work with seed companies to invest in deployment of climate-resilient and nutritionally enriched maize seed, and generate demand for such products,” Prasanna says.

Read more here: https://seedworld.com/starting-with-seeds/

East Africa partners welcome “new era” in wheat breeding collaboration

Representatives from ministries of agriculture and national agricultural research systems (NARS) in Ethiopia and Kenya recently joined funder representatives and technical experts from the International Maize and Wheat Improvement Center (CIMMYT) to renew a long-standing collaboration under the auspices of an ambitious new project, Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG).

AGG is a 5-year project that brings together partners in the global science community and in national agricultural research and extension systems to accelerate the development of higher-yielding varieties of maize and wheat — two of the world’s most important staple crops. Funded by the Bill & Melinda Gates Foundation, the UK Foreign, Commonwealth, and Development Office (FCDO), the U.S. Agency for International Development (USAID) and the Foundation for Food and Agriculture Research (FFAR), AGG fuses innovative methods that improve breeding efficiency and precision to produce varieties that are climate-resilient, pest- and disease-resistant, highly nutritious, and targeted to farmers’ specific needs.

Ethiopia and Kenya: CIMMYT’s longstanding partners

The inception meeting for the wheat component of AGG in East Africa drew more than 70 stakeholders from Ethiopia and Kenya: the region’s primary target countries for wheat breeding. These two countries have long-standing relationships with CIMMYT that continue to deliver important impacts. Ninety percent of all wheat in Ethiopia is derived from CIMMYT varieties, and CIMMYT is a key supporter of the Ethiopian government’s goal for wheat self-sufficiency. Kenya has worked with CIMMYT for more than 40 years, and hosts the world’s biggest screening facilities for wheat rust diseases, with up to 40,000 accessions tested each year.

AGG builds on these successes and on the foundations built by previous projects, notably Delivering Genetic Gain in Wheat, led by Cornell University. The wheat component of AGG works in parallel with a USAID-funded “zinc mainstreaming” project, meeting the demand for increased nutritional quality as well as yield and resilience.

CIMMYT Director General Martin Kropff gave key remarks at the stakeholder gathering, which took place Thursday, August 20.

“Cooperation between CIMMYT and Ethiopia and Kenya – as in all the countries where CIMMYT works – has had tremendous impact,” he said. “We are proud, not for ourselves, but for the people we work for: the hundreds of millions of poor people and smallholders who rely on wheat and maize for their daily food and incomes.”

“AGG will raise this spirit of global cooperation to a new level.”

AGG Project Leader and CIMMYT Interim Deputy Director General for Research Kevin Pixley introduced the new project as a “unique and important” project that challenges every stakeholder to grow.

“What we would like to achieve is a step change for all of us, he told the stakeholders. “Each of us has the opportunity and the challenge to make a difference and that’s what we’re striving to do.”

Representatives from the agricultural research communities of both target countries emphasized the significance of their long collaboration with CIMMYT and their support for the project.

The Honorable Mandefro Nigussie, Ethiopia’s State Minister of Agriculture, confirmed the ongoing achievements of CIMMYT collaboration in his country.

“Our partnership with CIMMYT […] has yielded several improved varieties that increased productivity twofold over the last 20 years. He referred to Ethiopia’s campaign to achieve self-sufficiency in wheat. “AGG will make an immense contribution to this. The immediate and intermediate results can help achieve the country’s ambitious targets.”

A holistic and gender-informed approach

Deputy Director of Crops at the Kenya Agriculture and Livestock Organization (KALRO) Felister Makini, representing the KALRO Director General Eliud Kireger, noted the project’s strong emphasis on gender-intentional variety development and gender-informed analysis to ensure female farmers have access to varieties that meet their needs and the information to successfully adopt them.

“The goal of this new project will indeed address KALRO’s objective of enhancing food security and nutrition in Kenya,” she said. “This is because AGG not only brings together wheat breeding and optimization tools and technologies, but also considers gender and socioeconomic insights, which will be pivotal to our envisaged strategy to achieve socioeconomic change.”

Funding partners keen for AGG to address future threats

Before CIMMYT wheat experts took the virtual floor to describe specific workplans and opportunities for partner involvement, a number of funder representatives shared candid and inspiring thoughts.

“We are interested in delivery,” said Alan Tollervey of FCDO, formerly the UK Department for International Development. “That is why we support AGG, because it is about streamlining and modernizing the delivery of products […] directly relevant to both the immediate demands of poor farmers in developing countries and the global demand for food – but also addressing the future threats that we see coming.”

Hailu Wordofa, Agricultural Technology Specialist at the Bureau for Resilience and Food Security at USAID highlighted the importance of global partnerships for past success and reiterated the ambitious targets of the current project.

“We expect to see genetic gains increase and varieties […] replaced by farmer-preferred varieties,” he reminded stakeholders. “To make this happen, we expect CIMMYT’s global breeding program to use optimal breeding approaches and develop strong and truly collaborative relationships with NARS partners throughout the entire process.”

“Wheat continues to be a critical staple crop for global food security and supporting CIMMYT’s wheat breeding program remains a high priority for USAID,” he assured the attendees.

He also expressed hope that AGG would collaborate other projects working in parallel, including the Feed the Future Innovation Lab for Applied Wheat Genomics at Kansas State University, and the International Wheat Yield Partnership.

FFAR Scientific Program Director Jeff Rosichan called AGG a “really ambitious project that takes a comprehensive look at the research gaps and challenges and how to translate that research into farmers’ fields.”

Agriculture prevails even under COVID-19

The global COVID-19 pandemic was not ignored as one of several challenges during this time of change and transition.

“As we speak today, despite the challenge that we have with the COVID-19, I am proud to say that work on the nurseries is on-going. We are able to apply [our] skills and deliver world-class science,” said Godwin Macharia, center director at KALRO-Njoro.

“This COVID-19 pandemic has shown us that there is a great need globally to focus on food equity. I think this project allows that to happen,” said Jeff Rosichan from FFAR.

Transformations are also happening at the research organization and funding level. CIMMYT Director General Martin Kropff noted that “demand-driven solutions” for “affordable, efficient and healthy diets produced within planetary boundaries” are an important part of the strategy for One CGIAR, the ongoing transformation of CGIAR, the world’s largest public research network on food systems, of which CIMMYT is a member.

Hans Braun, director of CIMMYT’s Global Wheat Program reminded attendees that, despite these changes, one important fact remains. “The demand for wheat will continue to grow for many years to come, and we must meet it.”

Cover photo: Harvesting golden spikes of wheat in Ethiopia. (Photo: Peter Lowe/CIMMYT)

Breaking Ground: Maria Itria Ibba and the lab that bakes bread

The rising and shifting demand for wheat, with rapid urbanization and increasingly globalized food markets, is pushing farmers more than ever to produce high-quality grain, according to the scientist who leads wheat quality research in the world’s foremost publicly-funded wheat breeding program.

“Wheat quality is becoming more and more important, as the industrial production of bread and other wheat-based foods increases to meet the demands of city dwellers, working women, and wheat consumers in wheat-importing countries,” said Maria Itria Ibba, head of the Wheat Chemistry and Quality Laboratory at the International Maize and Wheat Improvement Center (CIMMYT).

“Companies that produce and market food for such consumers demand high, consistent quality in grain they purchase and we have to help wheat farmers to meet stringent requirements.”

This is so important that CIMMYT’s Global Wheat Program — whose contributions figure in more than half of the wheat varieties released worldwide — directly uses lab data on milling, processing and end-use quality to decide which bread and durum wheat lines to move forward in its breeding programs, according to Ibba.

“Assessing quality is a huge task, because wheat is used to make hundreds of different foods, including all kinds of leavened bread, flat breads, pastas, noodles and steamed bread,” said Ibba. “Our lab is an integral part of breeding, analyzing thousands of grain samples from thousands of wheat lines each year for nearly a dozen quality parameters.”

Cut out for quality

A native of Viterbo, Italy, Ibba has led the Wheat Chemistry and Quality Laboratory since 2019 and is uniquely qualified for the job, with a bachelor’s degree in biotechnology, a master’s degree in biotechnology for the safety and quality of agricultural products — both from the University of Tuscia, Viterbo — and a doctorate in crop science from the Washington State University. Her Ph.D. dissertation addressed “low-molecular-weight glutenin subunit gene family members and their relationship with wheat end-use quality parameters.”

With a mother who studied medicine and a father who worked at the Italian Space Agency, Ibba said that in school she always enjoyed science subjects such as biology and chemistry. “They were easy for me to understand and I really liked how, after studying them, I was able to explain and understand many things around me.”

Ibba said the biggest challenges for her and her lab team are to understand wheat quality needs and conduct faster and better analyses.

“Several of the tests we do are expensive, time-consuming, and require skilled personnel and significant amounts of grain,” she explained, citing the use of exotically named devices such as the “Quadrumat Senior mill,” the “mixograph,” and the “alveograph,” to list a few. “We’re continuously looking for novel methods that are quicker, use smaller samples of grain, and with lower costs.”

Understanding the biochemical and genetic bases of wheat grain and flour quality traits is key to this, according to Ibba, but wheat quality traits are so complex genetically that DNA markers are of little help in breeding. “We’ve begun to explore whole genome selection for wheat quality traits, in collaboration with Kansas State University, but this will never completely replace the laboratory tests.”

Let’s talk health and nutrition

A staple of tours for the hundreds of visitors that come each year to CIMMYT in Mexico, the wheat quality laboratory combines the razzle-dazzle of high-tech devices with hands-on, sensory attractions such as inflating dough balls and freshly baked test loaves.

Ibba’s work includes talking to visitors about wheat, its important history and role in human nutrition and food, and concerns in the popular media regarding wheat and health.

“I think people know more now about what gluten is and its importance, but there is still the need to talk about gluten and wheat so that people can make informed decisions based on scientific facts,” she said. “I was happy to see the recent article from CIMMYT on a review study which, among many other things, showed there was no scientific evidence for the idea that eating refined flour is bad for your health.”

“Wheat provides about 20 percent of calories and protein for more than 4.5 billion people in developing countries,” Ibba pointed out. “There’s an increasing focus on understanding and improving the nutritional quality of wheat and its products because of the greater overall interest in diets and in the nutritional value of diverse foods.”