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Climate change can cause an increase in arid soils, warmer weather, and reduce water availability, which in turn can directly affect food security. This increases food prices and reduces the availability of food. Therefore, knowledge concerning the nutritional and technological potential of non-traditional crops and their resistance to heat and drought is very interesting. Pearl millet is known to produce small nutritious cereal grains, which can endure both heat and dry conditions, and is one of the basic cereals of several African and Asian countries. Although this species has been cultivated in Brazil for at least 50 years it is only used as a cover crop and animal feed, but not for human consumption. Nonetheless, pearl millet grains have a high potential as food for humans because they are gluten-free, higher in dietary fiber content than rice, similar in lipid content to maize and higher content of essential amino acids (leucine, isoleucine and lysine) than other traditional cereals, such as wheat and rye. In addition, the crop is low cost and less susceptible to contamination by aflatoxins compared to corn, for example. Most grains, including pearl millet, can be milled, decorticated, germinated, fermented, cooked and extruded to obtain products such as flours, biscuits, snacks, pasta and non-dairy probiotic beverages. Pearl millet also has functional properties; it has a low glycemic index and therefore it can be used as an alternative food for weight control and to reduce the risk of chronic diseases, such as diabetes. Thus, this review intends to show the potential of pearl millet as an alternative food security crop, particularly in countries, like Brazil, where it is not commonly consumed. Also this review presents different processes and products that have been already reported in the literature in order to introduce the great potential of this important small grain to producers and consumers.

Passion fruit mesocarp flour (MF) is a material of low-cost, because it can be produced from industrial processing of juices. The aim of this study was to develop flexible films based on MF, and to characterize their barrier, chemical, microscopic, thermal and mechanical properties, as well as to evaluate the rheological properties of the filmogenic solution used to produce them. The use of clay nanoparticles (NP) was also investigated. Films from MF were prepared by casting method, with glycerol as a plasticizer. The film forming solution of MF was more viscous than solutions of starch. The results of the contact angle values showed that films made from MF are more hydrophilic compared to starch, but there was no significant difference in water vapor permeability (WVP) and the thickness between these two different matrices. Regarding mechanical properties, the films made from MF proved to be tougher, stronger and less flexible. The formulation based on a mixture of MF and starch resulted in films less rigid and less resistant to tension, as compared to films based only on MF. The addition of NP did not influence the barrier properties, thermal and mechanical properties of films. Therefore, preparing films from MF, a cheap material, is a new alternative for taking waste from juice industries.

In the production of oil from sesame (Sesamum indicum L.) seeds, a coproduct is obtained which is rich in protein and fiber contents. Mixtures of semi-defatted sesame cake (SDSC) (0-20%) and corn grits were processed in a single screw extruder at screw speed ranging from 324 to 387 rpm to improve the nutritional value of corn expanded extrudates. Chemical composition of raw and extruded materials, sectional expansion index (SEI), texture properties, color, paste viscosity, microstructure and sensory analysis of the extrudates were performed. The addition of SDSC increased protein, fat and ash content of corn extrudates, whereas carbohydrate content was reduced. The addition of SDSC reduced the sectional expansion of the corn extrudates and increased puncture force. SDSC-corn extrudates were darker than non-SDSC-corn extrudates. Increasing SDSC increased the number of cells similar to those of commercial corn extrudates with small cells. Sensory analysis showed 20% SDSC-corn extrudates to be acceptable and nutritional balanced. The use of SDSC on corn extrudates up to 20% is an alternative to improve nutritional value keeping good sensory characteristics.

The influence of added sucrose on the degree of expansion and extent of starch conversion on extrusion processing of wheat flour and maize grits has been reported.Very different behaviour was found for the two cereal systems. In agreement with previous work, replacement of maize by sucrose at constant water content reduced the specific mechanical energy and as a consequence, reduced the degree of starch conversion and sectional expansion. In contrast, replacing wheat flour by sucrose even at levels as high as 20% of the flour weight had little effect. Possible causes discussed were less efficient plasticization of wheat flour by sucrose compared with maize grits at low water contents, a specific role for gluten and the larger particle size of maize grits compared with wheat flour.

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