Gluten-Free Breadmaking with Extruded Whole-Grain Andean Maize Flours

Andean maize can be safely used in gluten-free bread formulation. Extrusion is a technology capable of promoting changes in the techno-functional properties of gluten-free flours, modifying their breadmaking properties. The objective of this study was to evaluate the effect of extrusion on the physical and physicochemical properties of Andean maize whole-grain flours (bolita race) and to determine the relationship between the changes to the textural properties of gluten-free dough and bread with the addition of extruded flours. The Andean maize whole-grain flours were extruded in a single-screw extruder. The moisture, temperature and screw speed were varied through an incomplete orthogonal design. The expansion degree of extruded products, the total soluble carbohydrates, and the gelatinization degree of the flours varied mainly with moisture and temperature extrusion. Flours with high, medium, and low degrees of gelatinization treatments were added at 20 % to native flours to make gluten-free dough and bread. The dough made with the addition of extruded flours increased their firmness and adhesiveness in relation to the control made with native flour alone. Bread made with extruded flours generally increased their hardness, gumminess, chewiness, and cohesiveness. Springiness only increased under conditions of high and low degrees of gelatinization. The dough made with extruded flour at the extruded condition of 100 °C-25%H-120 rpm, with the lowest degree of gelatinization, were the least firm and adhesive, which could lead to better dough machinability. Additionally, the bread made with this flour presented high cohesiveness and springiness.

Effect of Die Configuration on the Physico-Chemical Properties, Anti-Nutritional Compounds, and Sensory Features of Legume-Based Extruded Snacks

Legumes are not valued by all consumers, mostly due to the prolonged soaking and cooking process they require. This problem could be solved by preparing legume-based ready-to-eat snacks. In this study, the effect of two different dies (circular and star-shaped, with cross-sections of 19.6 and 35.9 mm2, respectively) on the physico-chemical properties, anti-nutritional compounds, and sensory features of extruded breakfast snacks was determined. Extruded products were obtained from 100% legume flours of red lentil, faba bean, brown pea, and common bean. The extrusion-cooking conditions were 2.5 g/s feed rate; 160 ± 1 °C die temperature; 16 ± 1 g/100 g feed moisture, and 230 rpm screw speed. Star-shaped extrudates showed a lower expansion ratio, degree of starch gelatinization, and water solubility index, as well as higher bulk density, hardness, crunchiness, and lightness (L*) values. The oligosaccharides showed non univocal variations by changing the die, whereas phytates did not vary at all. The extrudates from lentil flour (richer in fiber) were the least preferred by sensory panelists, due to their hard texture. However, the spherical extrudates were preferred over the star-shaped product. These results emphasize the possibility of improving the physico-chemical and sensory properties of legume extrudates by selecting a proper die.

Experimental determination of physico-chemical and disperse characteristics and thermal parameters of sheep tail fat

The article discusses the experimental determination of the level of salinity, melting temperature, dispersed composition of crushed sheep tail fat, its moisture content and analysis of the state of moisture in it, and presents the results of these studies. The information obtained is necessary because the approach recommended by the authors contributes to a longer storage of the final product. Systematization of the advantages and disadvantages of the known technologies of smoked sheep tail fat, will allow to compose a rational technological flow of the production of this product and also to determine the rational operating parameters of the implementation of its stages. The information presented in the article on the physicochemical and dispersed characteristics, as well as the thermophysical parameters of sheep tail fat is relevant. At present, researchers have increased their interest in extruded products with a developed structure, obtained on the basis of raw materials of animal origin, as a source of high-quality fats, as well as a basis for therapeutic and prophylactic nutrition products of various technological forms.

Response surface analysis and process optimization of non-cereal (elephant foot yam, taro and water chestnut) snacks

The present study was conducted to develop non-cereal starch extruded products. The effects of feed moisture (15-21%), temperature (130-170 °C) and screw speed (120-160 rpm) were evaluated on the physical and functional properties of extruded snacks using response surface methodology. Feed moisture and screw speed increased the bulk density and hardness of extruded snacks. Significant decreases in water absorption index and increases in water solubility index were observed with increases in extrusion temperature. The best conditions were determined by numerical optimization. The optimized value for non-cereal snacks for feed moisture is 18.22%, temperature 155.96 °C, screw speed 142.75 rpm and, desirability is 0.75. Verification of results showed decent agreement between the responses of experimental values at certain optimum conditions and the predicted values.

Effects of Extrusion Conditions on Physical Properties of Sorghum Based Extruded Products

Extrusion cooking is a high temperature short time multivariable unit operation. In this study, response surface methodology (RSM) was used to evaluate the effect of feed parameters i.e., feed moisture (8-16%), blend ratio of sorghum:barley:bengal gram, (70:15:15 to 50:35:15) and machine parameters of twin screw extruder i.e., barrel temperature (120-200oC) and screw speed (120-200 rpm) on physical properties of extrudates i.e., mass flow rate, bulk density and moisture content. The results showed that maximum mass flow rate (0.974 g/s) was observed with the blend ratio 60:25:15, having 8 percent moisture (w.b) extruded at 160oC barrel temperature and a screw speed of 160 rpm. The bulk density of extrudates was found minimum (0.08 g/cc) at 10% moisture content, 65:20:15 blend ratio, 180oC barrel temperature and 180 rpm screw speed and the moisture content of extrudates was found minimum (4.74%) at 10% moisture content, 55:30:15 blend ratio, 180oC barrel temperature and 140 rpm screw speed.

Benefits and Challenges in the Incorporation of Insects in Food Products

Edible insects are being accepted by a growing number of consumers in recent years not only as a snack but also as a side dish or an ingredient to produce other foods. Most of the edible insects belong to one of these groups of insects such as caterpillars, butterflies, moths, wasps, beetles, crickets, grasshoppers, bees, and ants. Insect properties are analyzed and reported in the articles reviewed here, and one common feature is nutrimental content, which is one of the most important characteristics mentioned, especially proteins, lipids, fiber, and minerals. On the other hand, insects can be used as a substitute for flour of cereals for the enrichment of snacks because of their high content of proteins, lipids, and fiber. Technological properties are not altered when these insects-derived ingredients are added and sensorial analysis is satisfactory, and only in some cases, change in color takes place. Insects can be used as substitute ingredients in meat products; the products obtained have higher mineral content than traditional ones, and some texture properties (like elasticity) can be improved. In extruded products, insects are an alternative source of proteins to feed livestock, showing desirable characteristics. Isolates of proteins of insects have demonstrated bioactive activity, and these can be used to improve food formulations. Bioactive compounds, as antioxidant agents, insulin regulators, and anti-inflammatory peptides, are high-value products that can be obtained from insects. Fatty acids that play a significant role in human health and lipids from insects have showed positive impacts on coronary disease, inflammation, and cancer. Insects can be a vector for foodborne microbial contamination, but the application of good manufacturing practices and effective preservation techniques jointly with the development of appropriate safety regulations will decrease the appearance of such risks. However, allergens presented in some insects are a hazard that must be analyzed and taken into account. Despite all the favorable health-promoting characteristics present in insects and insects-derived ingredients, willingness to consume them has yet to be generalized.

Characteristics of Newly Developed Extruded Products Supplemented with Plants in a Form of Microwave-Expanded Snacks

The following research focuses on the possibility of applying fresh plant material as a carrot pulp to supplement newly developed extruded products in the form of pellets and microwave-expanded snacks. Fresh carrot pulp, as a valuable vegetable ingredient, was used in the amount of 2.5 g/100 g to 30.0 g/100 g in a potato-based recipe. The snack pellets were processed via extrusion-cooking, using a single-screw extruder with a plasticizing unit L/D = 18, and the use of variable screw speeds. The produced pellets underwent microwave expansion to limit the fat content, so as to produce ready-to-eat (RTE) snacks. The pellets and snacks were tested for nutritional value, as well as for selected quality features: physical properties, structure, pasting characteristics, and texture profile, and PCA analysis and a correlation matrix were performed on the obtained results. Microwave expansion of pellets increased the total phenolic content, the antioxidant activity, water absorption index and lightness of snacks, but decreased the bulk density and setback values of the expanded products when compared to pellets. Generally, we found that it was possible to use up to 30.0 g/100 g of fresh carrot pulp with a positive effect on nutritional value, and without negative effects on the physical properties of extruded products. Both the extrusion-cooking and microwave expansion can minimize the negative impact on plant materials, due to the short processing time.

An Analysis for Magnesium Alloy Curvature Products Formed by Staggered Extrusion (SE) Based on the Upper Bound Method

Staggered extrusion (SE) is a new method to solve the bottleneck of traditional curvature products, such as long manufacturing cycle, many forming processes and difficult quality control. How to quantitatively control the curvature of extruded products is the key to implement this method. Herein, the upper bound method is used to calculate and analyze the power consumption of each characteristic zone in the SE process. The theoretical model of extrusion load and curvature is established. The results show that the staggered distance h has an important influence on the curvature κ. When the staggered distance h increases from 8 mm to 24 mm and other conditions remain unchanged, the curvature κ increases from 0.0546 to 0.1607. Any combination of the staggered distance h and the extrusion ratio λ corresponds to an eccentricity ratio ξ. The eccentricity ratio ξ decreases with the increase of the staggered distance h or the extrusion ratio λ. By comparison, it can be seen that the variation trend of the theoretical predicted value and the FE modelling in the steady-state extrusion stage is consistent. The experimental results are in good agreement with the curvature theory prediction model. These results provide a scientific basis for the formulation of the SE process and precisely controlling magnesium alloy curvature products.

Effects of micronized-roasted coffee concentration and temperature process on technological properties of rice-based extruded

New ingredients have been used in extruded products to increase the healthiness and regionalization of these products. However, the process variables that can interfere with the technological quality of the product should be studied, aimed at good acceptance by consumers. This study aimed to evaluate the effects of the concentration of micronized roasted coffee (MRC) and the barrel temperature on the technological properties of rice-based extrudates. The extrudates were made with 3 and 8% MRC to replace rice flour and processed in a mono-extruder at 140 and 180 oC. They were characterized for color, expansion index, hardness, bowl-life, porosity, water absorption index, and solubility index, and paste properties. To assess the effects of the process variables, analysis of variance, and Scott-Knott test (p <0.05) were applied to compare the means. The increase in MRC concentration reduced the color parameters and hardness, while the increase in temperature affected the expansion index. A joint effect of the variables concentration and temperature was observed for the other properties evaluated. The study showed that MRC is a potential source of fibers and natural pigments, with a direct effect on the main technological properties of the final product.