Gluten is the protein complex found in grains such as wheat, rye and barley that is responsible for the elastic texture of the dough. Unfortunately, its central role in bread production and bread quality cannot be replaced by a single ingredient.
This is what makes formulating products like Gluten-Free Bread (GFB) so challenging for food scientists and manufacturers, especially since the demand for premium products is growing in parallel with the number of people adopting a gluten-free lifestyle.
as per A study conducted by Brazilian scientistsFrom the Federal University of Sao Paulo (UNIFESP) – Published in a special issue “Improving the nutritional and sensory quality of gluten-free bread” of FoodsApril 2021 – There is a dramatic increase in the number of people adhering to the GF diet, in part due to an increased incidence of gluten-related disorders such as celiac disease – “Which has become a notorious problem in public health worldwide” – but is mainly driven by the common belief that a GF diet is healthier and more suitable for weight management.
Celiac disease is a chronic dysfunction of genetic origin that affects 1.4% of the world’s population and can lead to multi-system disorders, with severe complications if left untreated.
Wheat allergy is an immune response to wheat proteins.
In contrast, non-celiac gluten sensitivity is not an autoimmune condition but is caused by gluten or other wheat ingredients such as fast fermentation carbohydrates. Its symptoms are often similar to celiac disease, but less severe.
“Three conditions are currently recognized as the basis for determining a gluten-free diet: celiac disease, wheat allergy and non-celiac gluten sensitivity,” Said Vanessa Diaz Capriles, lead researcher in research, nutritionist and professor at UNIFESP.
The challenge of creating GFB files
While the development of premium GF products continues and develops successfully, GF breads, for example, generally have a shorter shelf life than gluten-bearing breads. This is due to retrogregation of starch, migration of water from the forum to the membrane, as well as the starchy raw materials and high water content used – two factors that accelerate aging and increase susceptibility to antimicrobial-preventive deterioration.
“Developing these products is a major technological challenge,”Added Prof. Capriles.
“Bread made from wheat flour has been an important human food for thousands of years. The sensory impressions it causes are deeply ingrained in people’s lifestyles. It is therefore important to develop improved versions of these products. Market research shows that consumers are dissatisfied with the appearance, aroma, variety and convenience of existing products. . “
Gluten-free bread is often also nutritionally poor.
“In general, it is made from refined starch like rice bran combined with corn starch, potatoes and cassava. It contains little fiber, protein, vitamins or minerals, and relatively large amounts of fat. It is not enriched with nutrients in many countries,” he said. Said Prof. Capriles.
Overcoming the challenges
The UNIFESP study – supported by the Sao Paulo Research Foundation (FAPESP) through a young researcher and multi-user equipment grants – focuses on ways to address these challenges, particularly to improve the overall nutritional value of GF products; Increase their acceptability towards consumers; And develop technologically relevant solutions.
Brazilian scientists have created more than 15 preparations that they believe were optimal, using various techniques, 50% -100% whole wheat GF wholemeal flour to increase fiber content, along with the addition of proteins, vitamins and minerals. Characterization of fresh bread included the volume specific to the loaf, moisture crumbs, firming crumbs, crumb grain and height / width ratio of the main slice, and sensory acceptability.
The use of soluble dietary fiber is known to improve physical properties, sensory acceptance, shelf life, nutritional content and glycemic response of GFB, so Brazilian scientists have analyzed a variety of raw materials, including whole wheat flour such as rice, sorghum and millet; Pseudo-grains such as amerna, quinoa and buckwheat; And others like chickpeas, dried beans and pine nuts.
For the study, the team consumed Vitacel Psyllium P95 powder from JRS Latinoamericana, rice flour from Urbano Agroindustrial, cassava starch from General Mills Brasil Alimentos, calcium propionate from Pantec Aditivos e Ingredientes para Indústria and spray inhibitors. Along with commercial wheat flour from J. Macedo (for the WB), water, eggs, sugar, soybean oil, salt and dry yeast.
Psyllium – a natural soluble bioactive fiber made from the husks of e seeds Plantago ovata Plant – Achieved the most positive results.
Psyllium is hygroscopic and expands to a gelatinous mass when mixed with water, and exhibits water-binding properties, gels and building structures that can increase dough viscosity, strengthen expanding cell boundaries, increase gas retention during baking and improve volume. It also reduces the moisture loss of crumbs, softness, cohesion and springiness during storage, thus improving the structure, texture, appearance, reception and shelf life of the GFB.
Each 100 grams of psyllium provides 80 grams of soluble fiber, and is known to help with constipation and satiety, glycemia, cholesterol control, diabetes and atherosclerosis.
Particularly impressive results were obtained by combining psyllium with chickpea flour.
“We were able to make bread with 17% psyllium,”Said Prof. Capriles.
“Because it absorbs water, dough made of psyllium can be shaped into many shapes, just like rolls and loaves of conventional wheat flour.
“In more recent studies, we have linked psyllium to chickpea flour and achieved remarkably good results. Aside from high and nutritious reception, its benefits include a low glycemic response. [it does not raise blood sugar significantly] And increased satiety in healthy people.
“A very interesting point is that it maintained its acceptability even after maintaining at room temperature for seven days.”
Conclusion and way forward
The results showed that psyllium improved GFB structure, mouthfeel and GFB acceptability, with no significant differences in psyllium-enriched GFB and wheat bread (WB) admissibility. During storage, the GFB control had a crumb solidity eight times that of the WB. The longest GFB modification delay was observed with an addition of 17.14% psyllium, while maintaining admissibility during storage compared to that of WB counterparts.
The next steps, according to Prof. Capriles, are to find industry partners who will take the formula from concept to commercialization, as well as move forward with research and development on a collaborative basis.
Psyllium improves the quality and shelf life of gluten-free bread
Authors: Vanessa Diaz Capriles, Camille Partley, Fernanda Garcia Santos, et al.
Food 2021, 10 (5), 954, 27 April 2021