Assessment of Technological and Sensory Properties, Digestibility, and Bioactive Compounds in Polentas from Different Maize Genotypes.

The sensory profile of polenta and the connections between technological attributes and varieties of maize have not been extensively studied. Thus, it is necessary to understand the possible effect of its consumption on consumers' health in terms of postprandial glucose levels and molecules associated with healthy activities. This work aims to study polenta's technological and sensory properties from different maize genotypes and evaluate their digestibility and the potential contribution of bioactive compounds on health. A commercial hybrid, two open-pollinated varieties, and three inbred lines were used. Grain physical determinations and physical-chemical semolina traits were determined. Polenta's technological quality was evaluated after simulated cooking. In vitro digestion was performed for polentas, and a sensory evaluation test was conducted. A significant correlation was found between semolina polyphenols and rapidly digestible starch (r = -0.6). Panellists characterised the genotype C6006 as having a good flavour, sandier mouthfeel, and low consistency. Also, the polenta from the hybrid exhibited sensory attributes more closely resembling commercial polenta in terms of maize odour, flavour, and consistency. The higher content of polyphenols presents in semolina affected the digestion of polenta, showing a lower proportion of rapidly digestible starch and a lower amount of bioaccessible protein fraction.

Technological and Sensory Quality of Gluten-Free Pasta Made from Flint Maize Cultivars.

The development of quality gluten-free products presents a major technological challenge in terms of structure, texture, and shelf life. However, there is insufficient information available to identify genotypes for obtaining gluten-free maize pasta of good acceptability and technological quality. The objective of this work was to evaluate the technological and sensory quality of gluten-free pasta made from different maize cultivars. The flint open-pollinated variety, flint inbred line, and three dent commercial hybrids were used. Grain and flour's physical characteristics and chemical composition were determined. Gluten-free pasta was made via extrusion, and its quality traits were studied. A sensory evaluation test was carried out. Flint cultivars showed the lowest values on swelling index (both 1.77) and water absorption (124.30 and 134.58%). Pasta swelling index showed a negative association r = -0.77 to sodium carbonate retention capacity (p = 8.5 × 10-5) and water retention capacity (p = 6.6 × 10-5). Evaluators' preference results showed a higher frequency of choices at the top level of preference (4) for the flint open-pollinated variety C6006. Thus, evaluators' choices showed a positive association between sample preference and firmness. Pasta preference and technological quality have a direct relationship with fast tests over grain, such as test weight and float index.

Sodium chloride replacement by potassium chloride in bread: Determination of sensorial potassium threshold and effect on dough properties and breadmaking quality.

High sodium intakes represent an important risk factor for hypertension, cardiovascular diseases and kidney diseases. Even during the current COVID-19 pandemic, hypertension was related to higher mortality rate in patients with coronavirus. Thus, it is necessary to apply strategies to reduce or replace sodium content in food most widely consumed, like bread. This work aimed at determining the sensorial potassium threshold when potassium chloride is used as a sodium chloride replacer in bread formulation, and at analyzing the effects of such replacement on the properties of dough and on the technological and sensorial quality of bread. A decrease was observed in dough rheological properties with NaCl reduction in the formulation. Sensorial potassium threshold was determined and KCl was used in bread formulation as a NaCl replacement up to 0.92% of the regular salt content (2%) undetected by its characteristic taste. NaCl reduction resulted in bread with lower specific volume, higher firmness, faster staling and clearer crust. KCl bread showed similar technological to 2% NaCl bread. Finally, it was possible to replace 50% of NaCl with KCl without reducing quality and consumer acceptability.

Effect of Wholewheat Flour Particle Shape Obtained by Different Milling Processes on Physicochemical Characteristics and Quality of Bread.

RESEARCH BACKGROUND: Wholewheat flour is a very good source of nutritional compounds and functional ingredients for human diet. However, it causes negative effect on bread quality. Different milling techniques can be used to obtain wholewheat flour, minimizing the negative effect of both bran and germ on bread quality. The aim of this work is to study the effect of particle size and shape of wholegrain flour on the interaction among the different components, water distribution, dough rheology and bread volume. EXPERIMENTAL APPROACH: Wholewheat flour of three varieties (Klein Rayo, Fuste and INTA 815) was obtained in cyclonic, hammer and roller mills. The characteristics of wholewheat flour were explored, and the water distribution and rheological properties of dough were determined by thermogravimetric analysis and Mixolab test, respectively. Finally, microscale bread was prepared. RESULTS AND CONCLUSIONS: The amount of water-soluble pentosans, damaged starch and wet gluten was affected by the milling procedure. Regarding dough rheological properties, wholewheat flour obtained in hammer mill had the lowest water absorption capacity and the highest developing time. This result could be mainly attributed to particle shape in these samples with large amount of endosperm attached to the bran, hindering protein unfolding. Thermogravimetric analysis showed that both fine and large bran particle size seem to have the same effect on water properties in wholewheat dough during heating. Bread made with Klein Rayo variety had the highest specific volume, indicating that wheat with high protein content and breadmaking quality is needed to make wholewheat bread. The results of this work showed that particle shape, rather than particle size, affected the quality of wholewheat flour for breadmaking. NOVELTY AND SCIENTIFIC CONTRIBUTION: The effect of milling type and particle shape of the wholewheat flour had a greater effect than the wheat variety. Thus, the wholegrain milling process should be carefully selected taking to account the shape of the produced particle. This may open new opportunities for developing wholewheat bread with better acceptance by consumers.

Physicochemical and functional properties of isolated starch and their correlation with flour from the Andean Peruvian quinoa varieties.

Quinoa has been recognized as a complete food due to its balanced nutritional composition. Quinoa flour is used as an ingredient to improve the nutritional and functional characteristics of cereal-based foods. The physicochemical and functional (thermal and pasting) properties of flours and isolated starches of three Andean Peruvian quinoa varieties (Blanca de Hualhuas, BH; Rosada de Huancayo, RHY and Pasankalla, PK) were studied and the correlation among them properties were evaluated in order to explore their possible uses as a food ingredient. Proximal chemical composition of flour and isolated starches from quinoa varieties showed differences. Isolated starches from quinoa varieties showed a XRD Type A crystallinity patterns with polygonal shapes, small size, higher crystallinity degree and lower amylose content (<15%). The thermal (gelatinization temperatures and enthalpies) and pasting (temperature and time of gelatinization and viscosities) properties of flours and isolated starches showed differences and the principal component analysis demonstrated that those properties are significantly correlated to the starch and fat content. Based on the differences found among physicochemical and functional properties, isolated starch and flour of BH, RHY and PK quinoa varieties have potential as food ingredient for several cereal-based products.

Physico-chemical characterization of protein fraction from stabilized wheat germ.

Wheat germ shows the highest nutritional value of the kernel. It is highly susceptible to rancidity due to high content of unsaturated fat and presence of oxidative and hydrolytic enzymes. In order to improve its shelf life, it is necessary to inactivate these enzymes by a thermal process. In this work the functional properties and some characteristics of the protein fraction of treated wheat germ were evaluated. Sequential extraction of proteins showed loss of protein solubility and formation of aggregates after heating. DSC thermograms showed that wheat germ treated for 20 min at 175 °C reached a protein denaturation degree of ~ 77%. The stabilization process of wheat germ affected significantly some functional properties, such as foaming stability and protein solubility at pH 2 and pH 8. Nevertheless, heating did not affect the water holding, oil holding and foaming capacity of protein isolates.

Yeast-Leavened Laminated Salty Baked Goods: Flour and Dough Properties and Their Relationship with Product Technological Quality.

The effect of protein composition and content on the characteristics and properties of laminated baked products has been studied for a long time. However, there are no flour quality parameters related to its suitability to produce yeast-leavened laminated salty baked products. The relationships among flour characteristics, laminated dough pieces and baked products were studied in order to establish flour quality parameters and help predict the quality of the products. Yeast-leavened salty laminated products made with hard wheat flour had better quality properties than the products made with soft wheat flour. Hydrophilic components and a high gluten network quality are responsible for the generation of a rigid structure and viscous dough. Consequently, during baking, the dough rises rather than extends laterally and does not experience any change in the expected shape. Among the analysed flour characteristics, glutenin macropolymer content, lactic acid and sodium carbonate solvent retention capacities together with dough viscosity and resistance to deformation were the variables which influenced the most the quality of yeast-leavened salty laminated products.