Effects of separated and combined amaranth, quinoa and chia flours on the characteristics of gluten-free bread with different concentrations of hydrocolloids

Rice and corn flour/starch are frequently used in the manufacture of gluten-free products, which are usually characterized by high starch content, low fiber content, poor texture, insufficient volume, short shelf life, fast staling, and easy crumbling. The objective of this study was to use amaranth, quinoa, and chia flours, separately or in combination, and corn starch in different ratios as an alternative to wheat/rice flours. Furthermore, several hydrocolloids (methylcellulose, carboxymethylcellulose, xanthan gum, and guar gum) were added at different levels (2, 3, and 4%) to the precited flours in order to improve the technological properties of gluten-free bread, enhance its nutritive value, and avoid the negative effects caused by the ingestion of gluten for coeliacs. The increase in pseudocereal flours’ ratios produced dark dough and resulted in a decrease in specific volume and an increase in moisture content and crumb texture hardness in all bread formulations (except in quinoa breads). The increase in hydrocolloids’ levels contributed to an increase in the moisture content, specific volume, L values of crumb color, and hardness of all breads. The formulations prepared with the lowest ratio of pseudocereal flours (10%) at the highest hydrocolloid concentration (4%) produced better quality bread than the control in terms of acceptability. Among the pseudocereal-containing breads, quinoa breads had the best specific volume and crumb hardness, followed by chia, mixture, and amaranth breads. The formulations containing natural hydrocolloids combined with amaranth, quinoa, and chia flours could be interesting to produce “better-quality and healthier” bread for coeliacs.


Introduction
Wheat is one of the most common grains in the world. It is used mainly in many food products like bread, pasta, noodles, bulgur, and couscous, or as a component in food processing. This is attributed to the functional properties of gluten proteins found in wheat flour. Gluten is characterized as the main structural protein and functional component of wheat. It mainly provides the viscoelastic properties of dough required to produce high-quality products (Dizlek and Awika 2023;Sapone et al. 2012). Nevertheless, gluten consumption causes some health problems for people who have allergic reactions or intolerances to gluten, like celiac disease (CD) (Culetu et al. 2021;Mariotti et al. 2009). Today, CD is known as a common genetic disease with a prevalence of 1-2% in the world population (Sapone et al. 2012). CD is an autoimmune disease caused by the ingestion of any food containing prolamins like wheat, barley, and rye (Dizlek and Özer 2016). The consumption of these foods leads to damage in the mucosa of the small intestine, causing malabsorption of nutrients; some mineral (iron) and vitamin (B12, D, and K) deficiencies can occur. The common symptoms of CD are wide and divided into classical intestinal (diarrhea or constipation, weight loss, abdominal pain, bloating, and excessive gas) and non-classical intestinal (anemia, fatigue, osteoporosis, depression, and neurological disturbances) (Barker and Liu 2008;Sapone et al. 2012;Skendi et al. 2018). The only real and effective treatment for this disease is, at present, a lifelong adherence to a gluten-free (GF) diet, so celiac patients (CP) should avoid consuming of any foods containing wheat, barley, or rye in their diets (Barker and Liu 2008;Dizlek and Özer 2016;Green and Cellier 2007;Mariotti et al. 2009).
The diets of people with CD are unbalanced since they are rich in carbohydrates but lack other macromolecules and essential nutrients needed for normal metabolism. Although gluten-containing grains should be avoided in the GF diets of CP, different types of starches, grains, legumes, tubers, and pseudocereals like buckwheat, quinoa, and amaranth can be used as wheat flour substitutes in baking (Dizlek and Özer 2016;Green and Cellier 2007). In the past few years, GF cereals like corn, sorghum, millet, or pseudocereals have been used to produce GF products, and this is a significant challenge for food research to reach high-quality GF products (Schoenlechner et al. 2010). In many studies (Alvarez-Jubete et al. 2009a, b;Culetu et al. 2021;Drub et al. 2021;Schoenlechner et al. 2010), pseudocereals have been investigated to be introduced into the application of GF products as GF ingredients. These ingredients can be a replacement for gluten-containing flours and other starches and boost the nutritional value of GF products as well. Pseudocereals are safe seeds for CP as they contain very little or no prolamins. They are also important energy sources with high nutritional value of protein, fat, dietary fiber, and minerals like calcium, iron, and zinc. As a result, using pseudocereals to produce GF breads increases the nutritional value of breads, which is also important and required for CP in their diets (Alvarez-Jubete et al. 2009a).
Rice and corn flour/starch are frequently used in the production of GF bakery products, which are usually characterized by high starch content, low fiber content, poor texture, insufficient volume, short shelf life, fast staling, and easy crumbling (Culetu et al. 2021;Dizlek and Özer 2016). In manufacturing bakery products, especially bread, using some additives as a substitute for gluten is considered among the matters that have been significantly emphasized by food science in recent years (Dizlek and Özer 2016). It was reported for GF food that finished products with improved quality can be manufactured using different food additives, and that particularly hydrocolloids can be successfully employed in the manufacture of GF bakery products to meet the functions of gluten to some extent (Lazaridou et al. 2007). Hydrocolloids improve the textural properties of the food in which they are used, retard the retrogradation of starch, improve the retention of moisture in food, and maintain the general acceptability of the product during storage (Dizlek and Özer 2016;Rosell et al. 2001).
The aim of this study was to use pseudocereal (amaranth, quinoa, and chia) flours, separately or in combination, and corn starch in different ratios (0-100%, 10-90%, 20-80%, and 30-70%, respectively) as an alternative to wheat or rice flour. Furthermore, a variety of hydrocolloids (methylcellulose, carboxymethylcellulose, xanthan gum, and guar gum) at different levels (2%, 3%, and 4%) and an emulsifier were added to the precited flours in order to (1) improve the technological properties of dough and bread, (2) enhance the nutritive value of GF breads, and (3) avoid the negative effects caused by the ingestion of gluten, particularly for the CP.

Grinding and preparation of seeds
All types of seeds (amaranth, quinoa, and chia) were received and placed in the refrigerator at 4 °C until they were milled using a grain mill. The grinding process was separately done for each type of seed using double-bladed milling machines (Spice & Herb Grinder IC-25B-China, Power: 3500W, Rotation Speed: 28.000 rpm). A kilogram of seeds was placed inside the machine and milled for 15 s. This procedure was applied three times to the same amount of seeds at different times to ensure complete milling. After grinding, the products were sieved through a 212-micron mesh and stored in airtight plastic jars. After filling these jars, they were placed in the storage room until they were used in bread-making. Table 1 presents the different ratios of the main components used (corn starch, amaranth, quinoa, and chia flour) in the bread-making. In all cases, corn starch was mainly used as a base flour in different ratios. Pseudocereal flours were used in various ratios (10%, 20%, and 30%) either separately or in combination. In some formulations (control), they were not used at all. Three combinations (2%, 3%, and 4%) consisting of four types of hydrocolloids (MC, CMC, xanthan gum, and guar gum) were employed in equal amounts with different concentrations (0.5%, 0.75%, and 1%). The amount of water used in each bread formulation was kept constant (120%), as were the amounts of emulsifier (SSL) (1.5%), sugar (2.5%), salt (1.5%), compressed yeast (4%), and sunflower oil (2.5%), all used in fixed ratios. The differences in bread formulations were in (1) the quantity of corn starch and (2) the type and quantity of flour and additives used.

Preparation of gluten-free bread
Bread was made according to Škara et al (2013) with some modifications. In the bread-making procedure, firstly, all ingredients were weighed according to the formulations in Table 1. The following step was to pour 70% of the water into the mixer (Kitchen Aid, KPM5, St. Joseph, MI, USA) with the addition of sugar, followed by salt, oil, and yeast. After 1 min of mixing to ensure that the sugar and salt were dissolved in water, the oil and yeast were thoroughly mixed with water. After that, the dry components, which were preweighed (the ratios of ingredients are different according to product code), were added and mixed well, and then the rest (30%) of the water was slowly poured into the mixture to get a homogeneous dough. The mixing was carried out for 5 min (speed 5). The dough was scaled into baking pans after mixing; 160 g into each pan. Pans were incubated in a proofing chamber for 70 min at 30 ± 2 °C and 80-90% relative humidity. The loaves were then baked in an electric oven (Fimak, EKF 60 × 80/2 Model, Konya, Turkey) at 220 °C for 30 min. After baking, the loaves were cooled for an hour at 25 °C in ambient conditions and stored in sealed polyethylene bags. Breads were analyzed 6 h after baking. Six loaves were produced each time. The experiments were performed in triplicate for each type of formulation.

Bread evaluation
The moisture content of bread was measured based on AACCI method 44-19.01 (AACC 2010). The method of rapeseed displacement was used to measure the bread volume after an hour post-baking (AACCI Method 10-05.01; AACC 2010). Specific volume was calculated by dividing bread volume by bread weight. Konica Minolta CM-5 was used to measure the color of GF doughs and the crust and crumb color of the fresh bread samples. Color reading was expressed by using the L, a, and b color scales (Alvarez-Jubete et al. 2009b). The L scale ranges from (0 black) to (100 white); the a scale extends from (− green hue) to (+ red hue), whereas the b scale ranges from (− blue) to (+ yellow) (Lazaridou et al. 2007). The crumb texture of breads was measured by conducting a texture profile analysis (TPA) using a TA:XT plus Texture Analyzer (Stable Micro Systems, UK) equipped with a 5 kg load cell and a 25 mm aluminum cylindrical probe according to Škara et al (2013) with some modifications. A slice (25 mm thick) was taken from the middle of the bread and placed under the probe to conduct the test. Test speed was 1 mm/s, and compression was set at 40%. TPA analysis was conducted 24 h after baking at 25 °C. Three replicas were made for each test.

Sensory analysis
Hedonic sensory evaluation of the fresh breads was conducted by a panel consisting of 30 non-celiac consumers (15 women and 15 men aged 17-60 years, untrained panelists, non-smokers, and healthy) in the sensory booth, where heat, light, smell, and sound conditions were controlled. The panelists were selected from the staff and students of Çukurova University. Before the sensory evaluation tests, they all agreed to taste the bread samples and stated that they had consumed the samples and had no allergies or intolerances to any of the ingredients present in the samples. They were also informed that they were testing GF breads. Panelists were asked to assess the fresh GF breads according to their appearance, color, texture, taste, and overall acceptability on a 5-point hedonic scale. The scale of values ranged from 1 (dislike extremely) to 5 (like extremely). Water (at room temperature) was provided to the panelists to clean their palates after eating each sample. Samples were coded with three-digit numbers and served to the panelists at random.
The Research Ethics Committee of the Çukurova University (Turkey) approved this study, and all the participants signed an informed consent form prior to enrolling in the study.

Statistical analysis
Results were analyzed using the IBM SPSS 22 statistics program. Data were analyzed using analysis of variance   (One-Way ANOVA). Significant differences (p < 0.05) were determined by the Duncan multiple comparison test.

Results and discussion
The effects of different levels of hydrocolloids on the external appearance and internal structure of gluten-free control (GFC) breads are presented in Fig. 1. The effects of the addition of various levels of amaranth flour, quinoa flour, chia flour, and mixture flour with different levels of hydrocolloids on the external appearance and internal structure of GF breads are presented in Figs. 2, 3, 4, and 5, respectively. Table 2 presents the moisture content of GF bread formulations. The addition of hydrocolloids increased the moisture content of breads in all formulations of GFC and pseudocereal breads. An increase in the moisture content of breads was observed when the concentration of hydrocolloids was increased. The increase in the ratio of pseudocereal flours also led to an increase in the moisture content of breads. All formulations of pseudocereal breads had moisture contents higher than those of GFC breads except in two cases: Q1 had the same moisture content as GFC1 and M3 had the same moisture content as GFC3 (p < 0.05). Hydrocolloids decrease the loss of moisture content during bread storage and thus reduce the dehydration rate of the crumb. The increase in the crumb moisture content was attributed to the constant dough consistency and the water binding capacity of the hydrocolloids (Guarda et al. 2004;Houben et al. 2012). Hydrocolloids are applied in bakery products to control water absorption and, consequently, improve the shelf life of products by keeping the moisture content constant and retarding the staling as well (Kohajdová and Karovičová 2009).

Bread moisture
These findings are consistent with the reports of Guarda et al (2004) and Dizlek and Özer (2016) who found that the addition of hydrocolloids increased the moisture content of fresh bread and GF bread, respectively, and that increase was clearer at high levels of hydrocolloids (p < 0.05). Mohammadi et al (2014) obtained the same results and found that xanthan gum-CMC significantly augmented the bread moisture (p < 0.05). Ozturk and Mert (2018) also reported that the addition of xanthan gum to the formulation of bread prepared from corn starch had a higher moisture content than that of the control breads. On the other hand, the inclusion of the pseudocereal flours slightly increased the moisture content of the pseudocereal-containing GF breads. Alvarez-Jubete et al (2009b) found that no significant differences were observed in the moisture content of the pseudocerealcontaining breads in comparison to the GFC breads. Additionally, Steffolani et al (2014) reported that the addition of chia at a ratio of 15 g per 100 g of rice flour reduced weight loss during baking.
When comparisons were made between amaranth, quinoa, chia, and mixture breads, significant differences were found. The highest moisture content was found in the 30% chia flour-containing breads.

Specific volume of breads
The results for the specific volume of the baked breads are presented in Table 2. The specific volume index of all breads significantly improved by increasing the level of Fig. 1 The effects of different levels of hydrocolloids on external appearance and internal structure of gluten-free control breads (GFC: glutenfree control breads; GFC1, GFC2, GFC3 are Formulation codes of bread formulations. Please see Table 1)  Table 1) 1 3 Fig. 3 The effects of the addition of various levels of quinoa flour with different levels of hydrocolloids on external appearance and internal structure of GF breads (Q: quinoa flour; Q1, Q2, … Q9 are Formulation codes of bread formulations. Please see Table 1) Fig. 4 The effects of the addition of various levels of chia flour with different levels of hydrocolloids on external appearance and internal structure of GF breads (C: chia flour; C1, C2, … C9 are Formulation codes of bread formulations. Please see Table 1)  Table 1] hydrocolloids, except for some formulations, especially the formulations of GF breads, which were prepared using high ratios of pseudocereal flours (30%). The addition of hydrocolloids significantly increased the specific volume of the GFC breads and the pseudocereal-containing GF breads, which were prepared with low and medium ratios (10% and 20%), except for A5 and A6, and that increase was evident at high levels (4%) of hydrocolloids (Figs. 1, 2, 3, 4 and 5).
According to Rosell et al (2001), hydrocolloids can improve dough development and gas retention. An improvement in the specific volume was obtained when adding 0.1-0.5% HPMC and 0.1-0.5% xanthan gum to wheat bread formulations (Guarda et al. 2004). In a similar way, Sciarini et al (2010) found a positive effect of hydrocolloids, especially xanthan, followed by CMC on the specific volume of GF breads made of 40% rice flour, 40% corn flour, and 20% soy flour (p < 0.05). Dizlek and Özer (2016) reported that the volumes and softness of the GF breads have been measured as maximum when HPMC was used alone in increasing order from 1 to 2%. They found that, while HPMC gum improved the volume and softness of bread more than xanthan gum, xanthan gum improved the pore structure of the crumb more than HPMC. In general, these hydrocolloids gave good quality bread in terms of moisture content, pore structure, and Neumann baking coefficient values when they were used in combinations rather than being used separately. Ozturk and Mert (2018) reported that the specific volume analysis showed that the addition of xanthan gum resulted in breads that were more voluminous than the control breads.
The replacement of corn starch by each of the pseudocereal flours adversely affected the specific volume of the pseudocereal-containing GF breads in comparison to the GFC breads, with the exception of some formulations that were better than the control (p < 0.05). This effect became more pronounced as the ratio of pseudocereal flours was increased.
Among the pseudocereal-containing breads, quinoa breads had a better specific volume than that of chia, mixture, and amaranth breads, as presented in Figs. 2, 3, 4 and 5. It is worthy of note that Q1, Q2, C1, and M1 breads had better specific volumes than their counterparts in control breads: GFC1 and GFC2. The specific volumes of Q3, C3, and M3 breads were the closest to that of GFC3 bread. While all the amaranth breads had the lowest specific volume among the pseudocereal-containing breads (p < 0.05).
Alvarez-Jubete et al (2009b) reported that the replacement of potato starch by quinoa flour resulted in breads with a higher volume (p < 0.05) in comparison with the control, which was made from 50% rice flour and 50% potato starch. While no difference in volume was found when potato starch was replaced by amaranth flour. Steffolani et al (2014) found that the inclusion of chia flour at a ratio of 15 g per 100 g of rice flour reduced the specific volume of breads. They reported that these differences could be attributed to the

Texture profile analysis of bread crumb
The crumb hardness results of the bread samples are shown in Table 2. The increase in the hydrocolloid concentration significantly increased the crumb hardness of GFC and pseudocereal-containing GF breads, especially in the breads that formulated with the highest hydrocolloid concentration (4%) (p < 0.05), except in the case of amaranth breads, where no significant difference was found between A8 and A9 (p < 0.05).
In previous studies, it was found that using several hydrocolloids, such as HPMC and xanthan gum (Dizlek and Özer 2016), xanthan gum and CMC (Mohammadi et al. 2014), and xanthan gum, guar gum, locust bean gum, HPMC, and pectin (Demirkesen et al. 2010), causes crumb softening in the GF bread, while other studies showed that the addition of xanthan gum results in an increase in the hardness of GF bread (Lazaridou et al. 2007;Schober et al. 2005), and wheat bread (Guarda et al. 2004). Despite the fact that there are some hypotheses about the hydrocolloid's mechanism, it has not yet been completely understood. The effects of hydrocolloids on the starch structure and mechanical properties result from two opposite phenomena: (1) an increase in rigidity because of the decrease in the swelling of the starch granules and amylose leaching, and (2) a weakening effect on the complex starch network structure due to the prohibition of interparticle contacts among swollen granules. It is perhaps a combination of both factors that determines the overall influence on the mechanical properties of bread structure; however, each effect is dependent on the specific hydrocolloid used for fortification (Guarda et al. 2004;Lazaridou et al. 2007;Mohammadi et al. 2014). Lazaridou et al (2007) reported that the crumb firmness was not significantly affected by the addition of CMC when added at 1-2% concentration compared to the GF control formulations prepared from rice flour and corn starch. Xanthan gum at both supplementation levels (1-2%) had an unfavorable influence on crumb firmness (p < 0.05). They also pointed out that the crumb firmness values increased by increasing storage time (p < 0.05); this is expected because of moisture loss as well as starch retrogradation phenomena. Similarly, Schober et al (2005) found an increase in the crumb firmness observed with the addition of xanthan gum in GF breads prepared from sorghum (P < 0.001). Also, Guarda et al (2004) reported that the hardness of the wheat bread increased by adding xanthan gum after 24 h of storage.
Contrary to these results, Mohammadi et al (2014) found that xanthan gum and CMC significantly decreased the crumb hardness of both fresh and stored breads (p < 0.05) in comparison with the control made from corn starch and rice flour. The reason for the softness is that water retention increases moisture content and, thus, causes retrogradation of starch and retards bread firming (Mohammadi et al. 2014). Also, Demirkesen et al (2010) investigated the optimization of GF formulations based on rice flour prepared using different hydrocolloids and emulsifiers and reported that the hardness of GF bread decreased with the addition of hydrocolloids. Similarly, Dizlek and Özer (2016) reported that in GF breads that contain only xanthan and/or HPMC as an additive (without a surfactant), the penetrometer values of the bread increased (the hardness of the GF bread decreased) as the level of hydrocolloid increased. Ozturk and Mert (2018) also found that the addition of xanthan gum caused lower hardness for bread based on corn starch. This can be attributed to the water binding ability of hydrocolloids, preventing water transfer from the bread crumb to the crust and delaying starch retrogradation.
A possible explanation for these studies' contradictory results is that the GF breads were prepared using different methods. In this study, the level of water used in the preparation of GF breads was low and constant in all formulations, while Mohammadi et al (2014) considered the level of water needed to maintain consistency. In addition, we used corn starch as a flour base to produce GFC breads and other pseudocereal-containing GF breads.
On the other hand, the inclusion of the pseudocereal flours with low and medium ratios (10% and 20%) of flours significantly decreased the crumb hardness of the pseudocereal-containing GF breads in comparison with GFC breads, except for some formulations. The inclusion of the pseudocereal flours with high ratios (30%) of flours significantly increased the crumb hardness of the pseudocereal-containing GF breads in comparison with GFC breads, apart from the 30% quinoa flour-containing breads. Alvarez-Jubete et al (2009b) reported that the replacement of potato starch by pseudocereal flour resulted in a softer crumb in comparison with the GFC. Amaranth breads had the softest crumb, and they were followed by the buckwheat and quinoa breads. Moreover, the crumb hardness of GF breads increased with storage time. All the pseudocerealcontaining GF breads were characterized by a significantly softer crumb. This is attributed to the presence of natural emulsifiers found in the pseudocereal flours (Alvarez-Jubete et al. 2009b). Steffolani et al (2014) found that the inclusion of chia flour at a ratio of 15 g per 100 g of rice flour resulted in a considerable increase in the crumb hardness of breads. This effect cannot be opposed to our findings for the chia breads and can be explained by the differences in the levels of water used. In our study, the amount of water used was at a fixed level (120%) in each bread formulation, while the amount of water used was 100% in the study of Steffolani et al (2014). This agrees with McCarthy et al (2005) who found that the increasing levels of water used significantly increased the specific volume (p < 0.01) and decreased the crumb hardness (p < 0.01) of breads.
The specific volume and crumb hardness of pseudocereal-containing breads were found to have a negative relationship in this study. With the exception of quinoa breads, the increase in the ratio of pseudocereal flours resulted in a considerable drop in the specific volume and an increase in the crumb hardness. Steffolani et al (2014) found that the inclusion of 15 g of chia flour resulted in a reduction in the specific volume and a greater increase in the crumb hardness of breads.

Crust and crumb color of the breads
Average values of GF dough color and crust color of bread samples were given in online resource. As shown in Table 3 and Figs. 1, 2, 3, 4 and 5, the increase in the concentrations of hydrocolloids significantly resulted in a lighter color (higher L values) for the crumb in all bread formulations (p < 0.05) and this effect was clearly observed at the highest hydrocolloid concentration (4%) but did not significantly affect the values of a and b except in a few cases. The lightening effect is attributable to the effect of the addition of hydrocolloid on the water distribution, which thus influences Maillard browning and caramelization reactions (Mezaize et al. 2009). Mohammadi et al (2014) found that the inclusion of CMC and xanthan gum resulted in a lighter color for the crumb and crust in all formulations, compared to the GFC breads, which do not contain gums (p < 0.05). The a and b scales of the crumb were not affected by the addition of gums in comparison with the control. Similar results were also found by Lazaridou et al (2007). The inclusion of xanthan gum gave a lighter color for the crumb and crust (p < 0.05), compared to the GFC breads, which were prepared from rice flour and corn starch, whereas the presence of CMC at 1% or 2% caused no significant increase in the lightness (L value) of the crumb.
As presented in Figs. 1, 2, 3, 4 and 5, the addition of the different pseudocereal flours significantly gave a darker color for the crust (data not shown) and crumb (lower L values) and higher a and b values of the bread crumb, compared to the GFC breads. This effect was more pronounced in the pseudocereal-containing GF breads made with high flour ratios (30%), followed by those made with medium flour ratios (20%) (p < 0.05). Gómez et al (2003) pointed out that the original color of ingredients can slightly affect the crust color of the breads. The main reasons for the color of the crust are the Maillard and caramelization reactions. The crumb color of breads, however, is usually like the color of the ingredients. This is attributed to the fact that the crumb does not reach such high temperatures as the crust. Among the pseudocerealcontaining breads (Figs. 2,3,4 and 5), quinoa breads prepared with high ratios of quinoa flour (30%) had the darkest crumb color, while chia breads made with high ratios of chia flour (30%) had the darkest crust color (data not shown). Amaranth breads made with the lowest ratio of amaranth flour (10%) had the lightest color for the crumb and crust. These findings agree with Alvarez-Jubete et al (2009b), who found that the replacement of potato starch by each of quinoa and amaranth significantly exhibited a darker color for the crumb and crust (p < 0.05) in comparison with the control. No significant differences were determined between quinoa and amaranth breads for the crumb color, whereas quinoa breads had a darker crust color. Also, Steffolani et al (2014) reported that the color of GF bread was affected by the addition of 15 g of chia flour, leading to a decrease in the L values of the bread crumb and an increase in the values of a and b.

Sensory evaluation of breads
The formulations prepared at the highest hydrocolloid concentration (4%) were selected for the sensory evaluation test due to their high values in bread evaluation. Table 4 and Fig. 6 shows that there are significant differences among the breads in terms of appearance, color, texture, taste, and overall acceptability; M3 gained the highest score (3.97) for the appearance of bread, while Q9 gained the lowest score (2.33) (even lower than 2.5 [neither like nor dislike]) in comparison to GFC (3) (p < 0.05). Q3 and M6 gained the same score for the color of bread (4), which was the highest score for color evaluation, while GFC gained the lowest score (2.53) (slightly exceeding a score of 2.5) (p < 0.05). M3 showed the highest score (4.30) for the texture of bread, while M9 showed the lowest score (2.63) in comparison to GFC (3.67) (p < 0.05). Also, M3 showed the highest score (3.62) for the taste of bread, while GFC showed the lowest score (2.62) (p < 0.05). Regarding the overall acceptability of bread, M3 gained the highest score (3.84), while Q9 gained the lowest score (2.83) in comparison to GFC (3.03) (p < 0.05).
It must be considered that the participants in the sensory evaluation test were not CP and were accustomed to eating wheat bread. Changes both in the flavor and texture of the GF breads adversely influenced the overall evaluation (Steffolani et al. 2014). In general, as expected, GF breads containing low ratios of pseudocereal flours (10%) gained the highest scores (M3, Q3, A3, and C3) among other breads. Pseudocereal flours may be introduced into a GF bread formulation without negatively affecting the sensory properties of the loaves. Moreover, pseudocereal flours represent feasible ingredients in the production of good-quality, healthy GF breads (Alvarez-Jubete et al. 2009b). Bodroža-Solarov et al (2008) reported that the sensory characteristics of the supplemented breads are acceptable with 10 -15% amaranth grain, while supplementation of 20% resulted in loaves with lower specific volumes compared to the control. Sanz-Penella et al (2013) indicated the level of amaranth flour addition in bakery products should not exceed 20 g/100 g to maintain product quality and preserve the principal nutritional benefit of this ingredient. In addition, Steffolani et al (2014) pointed out that the addition of 15% chia did not change the overall evaluation of GF breads.
The increase in the concentration of hydrocolloids and the ratio of pseudocereal flours generally produced darker dough (data not shown). The moisture content of breads increased as the levels of hydrocolloids and the ratios of pseudocereal flours increased. The increase in the concentration of hydrocolloids significantly improved the specific volume index of all breads, except in some formulations of pseudocereal-containing GF breads, especially those formulated with the highest ratio of pseudocereal flours (30%). The addition of the pseudocereal flours adversely affected the specific volume of the pseudocereal-containing GF breads in comparison with the GFC breads, except for some formulations that were better than the control. The use of hydrocolloids significantly lightened the crumb color in all bread formulations. The incorporation of pseudocereal flours into a GF formulation produced a darker GF bread crumb than that of control bread (p < 0.05). The increase in the pseudocereal flours produced a darker bread crust color in all pseudocereal-containing GF breads. The addition of hydrocolloids increased the crumb hardness of all bread formulations. The inclusion of the pseudocereal flours in low and medium ratios (10% and 20%) significantly decreased the crumb hardness of the pseudocerealcontaining GF breads in comparison to GFC breads, apart from some formulations that had higher values of crumb hardness than their counterparts in the control breads. The inclusion of the pseudocereal flours in high ratios (30%) significantly increased the crumb hardness of the OVERALL ACCEPTABILITY (0-5 SCORE) Fig. 6 The pie diagrams for the sensory analysis of GF breads pseudocereal-containing GF breads in comparison to GFC breads, except for the 30% quinoa flour-containing breads.

Conclusions
Our findings show that GF bread formulations with 10% pseudocereals are superior to those with 20% and 30%. These formulations can be used to produce GF breads with a pleasant flavor, a favorable external appearance, and well-homogeneously distributed cells. The increase in moisture content, specific volume, L values of crumb color, and hardness of the crumb texture of all breads was associated with the increase in the level of hydrocolloids. In general, the highest results in terms of moisture, specific volume, color, texture, and overall acceptability of breads were found for the pseudocereal-containing GF breads with the lowest ratios of flours (10%) at the highest hydrocolloid concentration (4%). Among the pseudocereal-containing breads, quinoa breads had the best specific volume and crumb hardness, followed by chia, mixture, and amaranth breads.
As a result, healthier and more nutritious breads for CP, as well as for all consumers and the food industry, were developed. GF breads with pseudocereal derivatives, which were appreciated by sensory panelists, will create product variety in kitchens and on menus. Furthermore, it is expected that the study's findings will benefit food and baking science, technology, and practitioners. The formulations containing natural hydrocolloids combined with amaranth, quinoa, and chia flours could be interesting to produce "better-quality and healthier" bread for coeliacs.