Physicochemical and sensory attributes of gluten-free sourdough breads produced from underutilised African cereal flours and flour blends

To seek potential alternative(s) for imported wheat in the African baking industry, the physicochemical parameters and sensory attributes of sourdough breads developed from locally sourced underutilised cereals and their blends were assessed. Processed sorghum (Sorghum bicolour), finger millet (Eleusine coracana) and pearl millet (Pennisetum glaucum) and their composites (50:50) were used to produce sourdough. Sourdough and flour-sourdough blends (30% sourdough) were used in making gluten-free breads. The protein content of the breads ranged from 16.29% to 39.26%, whereas the fat, crude fibre, ash and carbohydrate contents fell between 14.02–18.80%, 0.55–1.22%, 1.90–3.32% and 42.16–65.61%, respectively. The calculated energy value of the gluten-free breads (405.99–446.39 Kcal per 100 g) exceeded that of wheat bread (396.43 Kcal per 100 g), while the specific loaf volume varied from 1.46 to 1.80 cm³ g⁻¹. Although the produced gluten-free breads have improved nutritional content compared to conventional wheat bread, they were at best moderately liked. This is perhaps due to the non-cohesive nature of the crumbs and psychological preference for known products. Further research targeted at improving the organoleptic properties of these sourdough breads is recommended.     

Effects of particle size distributions of rice flour on the quality of gluten-free rice cupcakes

The particle size distributions (PSD) of rice flour and milling processes are important in making gluten-free products. The dry rice flour was prepared by grinding dried rice grains after soaking. Effects of PSD on the quality of rice cupcakes were investigated using the newly-developed rice flour. The flour properties passed through 80, 120, 160, and 200 (<180, <125, <95, and <75 μm) meshsieves, and batters and cupcakes prepared from their flours were analyzed. The PSD patterns showed two peaks containing cells and free starch fractions, in which the starch fraction peak intensity increased as a particle size decreased. While damaged starch, water binding capacity, solubility and lightness increased, crude protein and yellowness decreased as a particle size decreased. The final and setback viscosities increased as a particle size decreased. The specific volume of cupcakes was the highest in the cupcakes made with rice flour passed through under 95 μm. Hardness and springiness decreased as a particle size decreased. The air cell sizes decreased as a particle size decreased with homogeneity. Air cell homogeneity, volume, hardness, and softness of cakes determined by the different test, and appearance, texture, and overall quality determined by the preference test were all significantly different (p < 0.05).     

Rheological,textural and sensory properties of gluten-free bread formulations based on rice and buckwheat flour

Mixolab, as the rheological instrument, was utilized to create gluten-free products. According to obtained Mixolab profiles, mixtures of rice flour and husked buckwheat and rice flour and unhusked buckwheat flour expressed rheological properties similar to wheat flour. In both types of mixtures the ratio of rice flour to buckwheat flour was 90:10, 80:20 and 70:30. According to the Mixolab profiles of the investigated systems, gluten-free products containing unhusked buckwheat flour had higher water absorption values, lower stability and weaker protein network structure, as well as lower peak viscosity than those consisted of husked buckwheat flour.Increasing the amount of husked buckwheat flour from 10% to 20% resulted in both G′ and yield stress value increase, but further increase of the husked buckwheat flour on 30% resulted in both G′ and yield stress value decrease. However, increasing the amount of unhusked buckwheat flour from 10% to 20% resulted in significant decrease of G′ and yield stress value having no significant impact with the addition of 30% of unhusked buckwheat flour.Hardness, expressed as a work of compression of the final product, increased with the amount of both types of buckwheat flour. Samples containing UBF expressed not significantly higher values of hardness than those prepared with HBF. According to obtained results of sensory evaluation of the final products it can be concluded that all six combinations of tested gluten-free breads were sensory acceptable.     

Physicochemical and sensory characteristics of restructured beef steak with added walnuts

The effects of different proportions (0, 5, 10, 15%) of added walnuts on the physicochemical and sensory characteristics of restructured beef steak were evaluated. The addition of 10 and 15% walnut reduced (P<0.05) cooking loss. Increasing proportions of walnut in the beef steak increased (P<0.05) water binding and reduced (P<0.05) fat binding properties. The addition of walnut did not affect (P>0.05) textural properties in uncooked restructured beef steak, but in cooked products Kramer shear force and bind strength were reduced (P<0.05) when 10% or more of walnut was added. Product morphology characteristics suggest that walnut interferes with the formation of protein network structures. Restructured steaks made with added walnut presented acceptable sensory properties. Incorporation of nuts in meat products can be use to confer potential heart-healthy benefits (Spanish Patent Application 200300367).     

Physicochemical and sensory properties of soy bread made with germinated,steamed, and roasted soy flour

For the development of healthful gluten-free soy bread acceptable to consumers, we evaluated the effects of various processing procedures for soy flour on bread quality, in terms of beany flavour and texture. We pretreated soy flour by both non-heating (raw:NS and germinated:GS) and heating (steamed:SS and roasted:RS) methods. In addition, to improve the loaf volume, we added 1% hydroxypropyl-methylcellulose (HPMC) to RS flour. Lipoxygenase activity was retained in the non-heat-treated flours (279 U/g for NS and 255 U/g for GS), but was significantly reduced in the heat-treated flours (106 U/g for SS and 69 U/g for RS). Moreover, heat-treated flour had higher isoflavone and ferric reducing antioxidant power than had non-heat-treated flour. However, RS flour had the lowest moisture content and lowest L^∗ value. The GS bread had the highest specific loaf volume (3.53 cm³/g), followed by NS (2.96 cm³/g), RS (2.25 cm³/g), and SS (1.81 cm³/g) bread. GS bread had the lowest hardness (1.53 N), followed by NS (1.65 N), RS (2.00 N), and SS (3.75 N) bread. The addition of 1% HPMC to RS increased the loaf volume (2.44 cm³/g), but decreased the bread’s hardness (1.80 N). As to the sensory properties, the bread with heat-treated flour was perceived to have a less beany odour and taste than was the bread with non-heat-treated flour. However, the latter had a better appearance than the former. These results indicated that soy flour pretreatment could enhance the loaf volume and reduce the beany flavour of whole soy bread.     

Physicochemical and organoleptic characteristics of seasoned beef patties with added glutinous rice flour

This study was conducted to determine if glutinous rice flour (GRF) could be a functional food additive to potentially replace corn starch (CS), soy protein isolate (SPI) and/or sodium tripolyphosphate (STPP) to improve the physicochemical and organoleptic characteristics of seasoned beef patties. GRF had a lower cook loss among the treatment groups due to an increase in fat and moisture retentions (p < 0.05). GRF lowered texture profile values for hardness, gumminess, springiness, and chewiness (p < 0.05) of the patties, which are generally beneficial for this product. The beef patties with GRF were juicier and more tender than the control and other treatments (p < 0.05). Hedonic scores for juiciness, tenderness and overall acceptability were the highest for the beef patties with 1 and 3% GRFs, suggesting that GRF may be an effective functional ingredient to improve the textural quality of seasoned beef patties.     

Physicochemical and organoleptic characteristics of seasoned beef patties with added glutinous rice flour

This study was conducted to determine if glutinous rice flour (GRF) could be a functional food additive to potentially replace corn starch (CS), soy protein isolate (SPI) and/or sodium tripolyphosphate (STPP) to improve the physicochemical and organoleptic characteristics of seasoned beef patties. GRF had a lower cook loss among the treatment groups due to an increase in fat and moisture retentions (p<0.05). GRF lowered texture profile values for hardness, gumminess, springiness, and chewiness (p<0.05) of the patties, which are generally beneficial for this product. The beef patties with GRF were juicier and more tender than the control and other treatments (p<0.05). Hedonic scores for juiciness, tenderness and overall acceptability were the highest for the beef patties with 1 and 3% GRFs, suggesting that GRF may be an effective functional ingredient to improve the textural quality of seasoned beef patties.     

Physical,textural and sensory characteristics of legume-based gluten-free muffin enriched with waxy rice flour

Food Science and Biotechnology - Physical, textural, and sensory characteristics of the gluten-free muffins made of mungbean and cowpea flours enriched with waxy rice flour were investigated....     

Incorporation of germinated mung bean flour with rice flour to enhance physical,nutritional and sensory quality of gluten-free cookies

Quality of the cookies substituted with germinated mung bean flour (GMF) to rice flour (RF) to produce gluten-free cookies were investigated in this study. The GMF was used to formulate with the RF to obtain the composite flours with different total protein contents of 6, 9, 12, 15, 18 and 21 (%, d.b). The increase in the substituted amounts of GMF contributed to the lower baking loss, diameter and spread ratio, but the higher thickness and hardness of the cookies as compared to the RF-based cookie. The cookies with more GMF substitution expressed lower lightness (L*) values, but higher redness (a*) and yellowness (b*) values than the others. The cookies substituted with 60% of the GMF (60-GMFC) exhibited similar baking loss, thickness, diameter, spread ratio and lightness values to the wheat flour (WF)-based cookies. The total amounts of essential amino acids and the sum of histidine, lysine and methionine of the composite flour-based cookies were 3.90% and 1.64%, significantly higher than those of the RF-based cookie (1.93% and 0.66%, respectively) or the WF-based cookie (1.70% and 0.58%, respectively). As a result, healthy gluten-free cookies could be prepared using the RF with the substitution of the germinated mung bean flour.     

Properties and qualities of rice flours and gluten-free cupcakes made with higher-yield rice varieties in Korea

Korean rice varieties, ‘Druryechanbyeo’ and ‘Boramchanbyeo’, were developed to get higher yields and to be used in rice products. The rice grains were dried and milled into rice flours after first going through the soaking process. The properties and qualities of cupcakes made with dry-milled rice flours were compared with cupcakes made with commercial dry-milled rice flours (CDRF). The newly developed rice flours (NDRF) had higher apparent amylose content, water binding capacity, swelling power, and peak viscosities, but had lower damaged-starch content, gelatinization temperature, and final and setback viscosities than CDRF. The specific gravity of batter, and hardness and springiness of cupcakes were lower in NDRF than in CDRF. The cake textures from ‘Boramchan’ NDRF were more preferable than those from ‘Druyechan’ NDRF. The specific volume and overall quality of cupcake were correlated positively with amylose content and water binding capacity, but negatively with damaged starch of rice flours.     

Physicochemical and functional properties of whole legume flour

The physicochemical, functional and pasting properties of whole flours from pinto bean, lima bean, red kidney bean, black bean, navy bean, small red bean, black eye bean, mung bean, lentil and chickpea were investigated. Significant differences in physicochemical characteristics and functional properties were observed (P < 0.05). Bulk densities, water absorption indices, water solubility indices, oil absorption capacities, emulsion activities, and emulsion stabilities ranged from 0.543 g/mL to 0.816 g/mL, 4.09 g/g to 6.13 g/g, 19.44 g/100 g to 29.14 g/100 g, 0.93 g/g to 1.38 g/g, 61.14%–92.20%, and 84.15%–96.90%, respectively. Phaseolus legume flour exhibited higher water absorption capacity, oil absorption capacity, emulsion activity, and emulsion stability compared with other kinds of legume flour. Pasting properties were significantly different (P < 0.05). Pasting temperatures and the peak, final, and setback viscosities of the flours ranged from 73.2 °C to 83.0 °C, 96.2 RVU to 216.8 RVU, 118.5 RVU to 243.8 RVU, and 28.3 RVU to 103.2 RVU, respectively.     

Functional and thermorheological properties of rice flour gels for gluten-free pasta applications

Based on the European Commission directives on circular economy, this work explores the functional and thermorheological properties of rice flour from broken kernels, a by-product from the rice industry, in order to evaluate its possible use in food applications, back into the value chain. Chemical and hydration properties of two rice varieties (Guiana – Indica spp, Ariete – Japonica spp) were accessed, as well as the impact of the rice variety on the texture and viscoelasticity of rice flour gels (6–26%). Both rice varieties presented statistically different physicochemical properties (protein, lipid and amylose contents), and hydration properties that support the distinct texture and rheology behaviour of gels obtained. Rheology results suggested the formation of a gel-network structure with high frequency dependence, especially at lower rice concentrations. Texture results suggest that both rice varieties could be suited for development of gluten-free products that require pre-gelatinised starch, such as pasta. The effect of gelatinised rice flour (10–25%) and gelatinised flour/rice flour ratio (40:60, 50:50, 60:40) on the physical properties and cooking quality of pasta were assessed. Better overall cooking quality and texture properties were obtained for the formulation with 20% gelatinised rice flour and 50:50 rice gel:rice flour ratio.     

Physicochemical and functional properties of Caryota urens flour as compared to wheat flour

Starch digestibility, thermal, pasting and gelling properties of Caryota urens (CU) flour were investigated using wheat flour as reference. Amylose content of CU and wheat flour was 32.1% and 28.3%, respectively. CU flour had very low content of protein and lipid but had a high content of total starch (98.2%) and resistant starch (RS) [42.5%]. Gelatinisation temperature (78.5 °C) of CU flour was higher than wheat flour. Pasting behaviour of CU flour was similar to that of high swelling tuber and root and waxy starches. CU flour retrograded to a greater extent than wheat flour. Very specific gelling behaviour was noticed for CU flour where it produced significantly harder gel with high paste clarity, fracture ability, adhesiveness, gumminess and chewiness. Expected glycaemic index (eGI) of CU and wheat flour was 92.4 and 100.4, respectively. CU flour had high eGI despite high content of resistant starch.     

Microbial, physical and sensory properties of yogurt supplemented with lentil flour

In this study, skim milk (9.5% w/v solid content) was supplemented with 1-3% (w/v) lentil flour or skim milk powder, inoculated with a yogurt culture, fermented and stored at 4 °C. Acid production during the fermentation, microbial growth, physical properties (pH, syneresis, and color), rheological properties (dynamic oscillation temperature sweep test at 4-50 °C), during 28 days of refrigerated storage and also sensory properties (flavor, mouth feel, overall acceptance and color) after production, were studied. Milk supplementation with 1-3% lentil flour enhanced acid production during fermentation, but the microbial population (CFU) of both S. thermophilus and L. delbrueckii subsp. bulgaricus were in the same range in all lentil flour and skim milk powder supplemented yogurts. The average pH of samples decreased from 4.5 to 4.1 after 28 days storage. Syneresis in 1-2% lentil flour supplemented yogurts was significantly higher than all other samples; however, greater lentil supplementation (3%) resulted in the lowest syneresis during the 28 days storage. With respect to color, “a” and “L” values did not significantly differ in all samples and remained constant after 28 days whereas “b” value increased as a result of lentil supplementation. Yogurt with 3% lentil flour showed higher storage (G') and loss (G?) moduli in comparison with samples supplemented with 1-3% skim milk powder and the non-supplemented control yogurt. Storage modulus (G') was higher than loss modulus (G?) in all samples and at all temperatures between 4 and 50 °C and they showed a hysteresis loop over this temperature range when the samples were heated and cooled. 1-2% lentil flour supplemented yogurt showed comparable sensory properties in comparison with 1-2% skim milk powder supplemented yogurt and the control sample.     

Physicochemical,nutritional and functional properties of marama bean flour

Marama bean is a protein-rich, underutilised, drought-tolerant legume in sub-Saharan Africa. Its utilisation may be increased through value addition into protein-rich flours. Defatted flour from unheated and dry-heated (150 °C/20 min) whole marama beans (UMF and HMF) were analysed for physicochemical and protein-based functional properties. Heating significantly increased in vitro protein digestibility of marama bean flour. Of functional importance are the high levels of tyrosine present in marama bean flours. Heating significantly reduced protein solubility and emulsifying capacity of marama bean flours whilst water absorption capacity was improved. Foaming capacity was not affected by heating. UMF could be useful in food systems requiring high emulsifying capacity, but would not be suitable for applications requiring high water absorption and foaming capacity. Due to its high protein contents, marama bean flour could be used to increase the protein quality of cereal-based foods to help alleviate protein-energy nutrition in the region.     

Physicochemical and functional properties of flour and protein isolates extracted from seinat (Cucumis melo var. tibish) seeds

The physicochemical and functional properties of seinat seed flour (SSF), defatted seinat flour (DSSF), and protein isolates were studied. Protein was extracted from DSSF using an alkali solution with isoelectric precipitation and freeze drying. Freeze dried seinat seed protein isolates (FSSPI), SSF, and DSSF were evaluated for their physicochemical and functional properties. SSF contained high levels of crude fat and fiber (31.13% and 24.75%, respectively). FSSPI contained 91.83% protein versus 28.58% for SSF. The amounts of potassium, the mineral with the highest content, were 9,548.33, 6,439.03, and 1,029 mg/100 g in SSF, DSSF, and FSSPI, respectively. The functional properties were variable among samples. The protein solubility of FSSPI was significantly higher (p<0.05) than for DSSF and SSF. FSSPI has a significantly better (p<0.05) foaming capacity, water/fat absorption capacity, and bulk density than SSF and DSSF. FSSPI also showed an emulsifying capacity comparable to commercial soy protein isolates.