Amaranth (Amaranthus caudatus), quinoa (Chenopodium quinoa) and kañiwa (Chenopodium pallidicaule) are pseudocereals regarded as good gluten-free sources of protein and fiber. A co-rotating twin screw extruder was used to obtain corn-based extrudates containing amaranth/quinoa/kañiwa (20% of solids). Box-Behnken experimental design with three independent variables was used: water content of mass (WCM, 15-19%), screw speed (SS, 200-500 rpm) and temperature of the die (TEM, 150-170 °C). Milled and whole samples were stored in open headspace vials at 11 and 76% relative humidity (RH) for a week before being sealed and stored for 9 weeks in the dark. Hexanal content was determined by using headspace gas chromatography. Extrudates containing amaranth presented the highest sectional expansion index (SEI) (p<0.01) while pure corn extrudates (control) presented the lowest SEI and greatest hardness (p<0.01). SEI increased with increasing SS and decreasing WCM. In storage, whole extrudates exposed to 76% RH presented the lowest formation of hexanal. This study proved that it was possible to increase SEI by adding amaranth, quinoa and kañiwa to pure corn flour. The evaluation of lipid oxidation suggested a remarkable stability of whole extrudates after exposure to high RH.

The effects of amaranth and quinoa supplements and extrusion‐cooking on the physical properties and chemical composition of corn‐based extrudates were investigated by using PLSR and L‐PLSR. Grain type, content of amaranth or quinoa flour (20–50% of solids of blend), temperature of die (140–160°C), screw speed (200–500 rpm), water content of mixture (14–18%) as well as contents of protein, ash, dietary fiber and main fatty acids of blend were the predictors in the PLSR and L‐PLSR. Water content of mixture and screw speed had the distinctly greatest importance for physical response variables such as torque and pressure at the die during extrusion, SEI, stiffness and water content of extrudate. Extrusion reduced the content of fatty acids and tocopherols in the solids but it had only a slight effect on the content of total phenolic compounds and folate. This study proved that extrudates containing up to 50% amaranth or quinoa can maintain some key physical properties (e.g., high SEI, low stiffness) and the added nutritional value (e.g., increased content of folate). This study applied successfully PLSR and L‐PLSR modeling techniques to study the incorporation of amaranth and quinoa to corn‐based snacks. Practical Applications It was possible to add up to 50% amaranth and quinoa and still, obtain expanded corn‐based extrudates. The incorporation of these grains increased the nutritional value of corn‐based extrudates, having little effect on their expansion and stiffness. Amaranth and quinoa could have a tremendous potential for the development of gluten‐free extruded snacks.

The results provide information about current program for contractors and clients, e.g. appropriate cleaning intervals of different surfaces, and the influence of disorder on result. After the evaluation of surface dust contamination levels, it will be possible for cleaning companies to focus on the most important surfaces to clean in order to enhance the quality of the indoor environment in office buildings. This should lead to future development work, which will require cooperation between contractors, clients, and research scientists. In office environments where high cleanliness is required, objective measurements (with instruments) are needed in addition to subjective measurements (the perceptions of occupants). It is essential to evaluate the efficiency of cleaning programs regularly with effective and appropriate quality-monitoring methods.

Kañiwa (Chenopodium pallidicaule) and lupine (Lupinus angustifolius) are good gluten-free sources of protein and fiber. The effect of various contents of kañiwa or lupine flour on physical and chemical properties of extruded snacks was investigated. Grain type (kañiwa or lupine), content of kañiwa or lupine flour (20-50% of solids), temperature of die (140-1608C), screw speed (200-500 rpm) and WCM (14-18%) as well as content of protein, ash, fiber and main fatty acids of blend were the predictors in the PLSR model 1. SEI decreased with increasing WCM and content protein and fiber of blend, and increased with increasing screw speed. The stiffness of extrudates containing kañiwa or lupine increased with decreasing screw speed, and increased with increasing WCM, and content of protein and fiber of blend. Extrudates with higher content of kañiwa or lupine presented higher retention of fatty acids and tocopherols while the content of total phenolic compounds and folate was comparable to that of unprocessed flour blends according to PLSR model 2. This study showed that extrudates containing up to 50% kañiwa and at most 20% lupine of solids can maintain high SEI as well as added nutritional value. This study applied successfully PLSR to study the incorporation of kañiwa and lupine to corn-based extrudates. PRACTICAL APPLICATIONSUp to 50% kañiwa and 20% lupine can be successfully added to expanded cornbased extrudates, thereby increasing the overall content of protein and fiber compared to pure corn extrudates. Extrusion had a minor effect on total phenolic compounds and folate, meaning that some of the nutritional value conferred by kañiwa or lupine was not lost under the conditions tested. Kañiwa, in particular, could have an outstanding potential for the development of gluten-free extruded snacks. Partial Least Squares modeling was a formidable tool to predict the effect of material and process variables on the physical and chemical characteristics of extruded snacks, thus giving valuable information for product development