Breadmaking performance and technological characteristic of gluten-free bread with inulin supplemented with calcium salts

Urszula Krupa-Kozak 0 1 Rossana Altamirano-Fortoul 0 1 Magorzata Wronkowska 0 1 Cristina M. Rosell 0 1 0 R. Altamirano-Fortoul C. M. Rosell Cereal Group, Institute of Agrochemistry and Food Technology (IATA-CSIC) , Av Agustn Escardino 7, 46980 Paterna, Valencia, Spain 1 U. Krupa-Kozak (&) R. Altamirano-Fortoul M. Wronkowska Department of Chemistry and Biodynamics of Food, Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences , Tuwima St., 10, 10-747 Olsztyn, Poland The fortification of gluten-free bread containing inulin with different organic and non-organic calcium sources was investigated. Calcium lactate, calcium citrate, calcium chloride and calcium carbonate were used as calcium sources. Gluten-free bread composed of corn starch, potato starch, salt, yeast, pectin, sugar and sunflower oil was used as a reference. The calcium salts were supplemented to the gluten-free formula to provide equal content of elementary calcium (Ca?2). The Mixolab device was used to analyse the behaviour of gluten-free dough subjected to a dual mechanical shear stress and temperature constraint. Calcium salts significantly modified the dough behaviour during heating and cooling. The addition of calcium carbonate and calcium citrate provoked an increase in dough consistency during heating and cooling compared with the other salt-enriched samples. The specific volume and texture parameters of gluten-free breads varied with the calcium salt used, but calcium carbonate and calcium citrate showed improved values. The higher calcium content of the enriched breads, compared with the control, confirmed the fortification. Sensory evaluation of the calcium-fortified breads confirmed that calcium carbonate followed by calcium citrate was the most recommended salt for obtaining calcium fortification of gluten-free breads. - Serologic screening studies have shown that the worldwide prevalence of coeliac disease (CD) is to be 0.31.2 % in unselected European, North American, South American and Indian populations [13]. Such a rate establishes coeliac disease as one of the most common genetically based diseases. That acquired and permanent enteropathy is caused by wheat gliadins and other prolamins, like secalin of rye, hordein of barley and possibly avenin of oat [4]. In patients suffering from CD, the reaction followed by the consumption of gluten-containing products leads to a small intestinal mucosal inflammation. This proximal location in the small intestine often results in malabsorption of calcium, iron, folic acid and fat-soluble vitamins. Patients newly diagnosed or inadequately treated often have low bone mineral density, which appears to be directly related to the intestinal malabsorption. Osteomalacia or osteopenia are secondary to the reduced calcium absorption, caused by atrophy of the intestinal villi, and/or to a vitamin D deficiency, leading to secondary hyperparathyroidism [5]. Osteoporosis is therefore a frequent complication accompanying coeliac disease [6]. Strict and lifelong adherence to a gluten-free diet is the only proven treatment for coeliac disease; however, glutenfree diet is extremely difficult to adhere to due to the ubiquity of gluten in human foods. Besides, many glutenfree cereal products provide lower level of B vitamins (thiamine, riboflavin or niacin) [7], folate, iron and dietary fibre [8, 9] than their enriched wheat-based counterparts, they are intended to replace. These deficiencies appear to be due to the use of refined grains or starches and the relative lack of vitamins and minerals enrichment. Many studies related to gluten-free bakery products have been focused on the design of gluten-free matrix to overcome the negative impact on the absence of gluten network. Newly developed gluten-free formulas are composed of different starches, functional ingredients, additives, and pseudocereals to mimic the viscoelastic properties of gluten resulting in the improvement of the structure, mouthfeel, acceptability and shelf-life of gluten-free products [1013]. Calcium has vital functions within cells in all living creatures, predominantly as a second messenger transmitting signals between the plasma membrane and the intracellular machinery. Extracellular calcium is also an essential cofactor in clotting factors and adhesion molecules and is essential for the proper formation of bones. Calcium deficiency is readily connected with osteoporosis, caused by a decreased of bone calcium content. Nutritional calcium deficiency may give rise to a number of so-called calcium paradox diseases (hypertension, arteriosclerosis, neurodegenerative diseases, malignancy, degenerative join diseases) caused by intracellular calcium overflow into soft tissue and intracellular compartment through the action of PTH [14], whereas a high calcium intake is suggested to prevent colorectal cancer [15] and decrease blood pressure and cholesterol level [16]. Calcium is an essential nutrient required in substantial amounts. In the UK, mandatory fortification of white flour with calcium carbonate contributes approximately 14 % of total calcium intake [17]. In Poland, the enrichment of flour and cereal products in calcium comes up to 3 g/kg of a product using mainly calcium carbonate [18]. Ranhotra et al. [19] have shown that flour can be fortified to contain Ca at high level without adversely affecting white gluten bread quality. Generally, gluten-free formulas and baked products are poor in minerals, including calcium [20, 21]. Calcium fortification of such products could increase the calcium content in the coeliac patients diet, allowing them to obtain the amount of calcium they need for prophylactic or therapeutic use. Many diets are deficient in calcium making supplementation necessary or desirable. Multiple forms of calcium supplements are available [22]. A variety of factors may impact the selection of a calcium supplement (e.g. medical conditions such as lactose intolerance, impaired gastric acid secretion and high-risk profile for kidney stone formation). Besides, the selection of the appropriate calcium salt for a specific food application should be based on the consideration of a number of properties associated with the respective product such as solubility, calcium content, taste and bioavailability. Calcium bioavailability depends on its chemical form and factors affecting its solubility. Low pH, basic amino acids, lactose, organic acids, bile salts and adequate calcium/ phosphorus ratio increase calcium bioavailability, whereas higher pH, non-soluble dietary fibre, phytates and oxalates greatly reduce calcium absorption. Calcium supplements vary in calcium content with the largest per cent of calcium (40 %) in calcium carbonate (most cost-effective and readily available in some antacids), with other salts such as citrate, lactate and gluconate furnishing 21, 14 and 9.3 % of calcium, respectively [23]. Currently, the dominant anions in the calcium s (...truncated)