Significance of storage conditions on the flow properties of wheat flours

Flow properties of wheat flours are influenced by their intrinsic properties and environmental conditions during handling. This study evaluated the effects of environmental conditions (temperature and relative humidity- %RH) and flour properties (particle size and wheat class) on the flow properties of wheat flours. Size fractions from hard red winter (HRW) and soft red winter (SRW) wheat were produced through sieving. Flour fractions were then exposed to various temperature (25 and 35 degree Celsius) and relative humidity (50, 60, and 70%RH) combinations (t=3 h) to evaluate the effects of environmental conditions. Flow indicators (Hausner ratio – HR and compressibility index - CI) and flow (bulk, dynamic, and shear) properties were measured for the wheat flours after treatment. Shape analysis showed that all flour fractions were spherical based on their aspect ratio (>0.7) and elongation (4.0) which indicates poorer flowability. Higher humidity levels (60 and 70%) also caused poorer flowability for the wheat flours after exposure. The results from this study show that both environmental factors and flour characteristics have significant effects on flour flow properties. Handling wheat flours at lower humidity levels and higher temperatures improve flowability. Hard wheat flours were more flowable than soft wheat flours; coarser fractions from both wheat types flow better than finer fractions

Pretreatment Methods for Biofuel Production from Sorghum

This chapter provides an overview of sorghum (Sorghum bicolor L.) biomass pretreatment methods to produce biofuels. Sorghum is an important food, feed, and fuel crop that serves multiple purposes of human food, pet food, animal feed, and feedstock for bioenergy production. There are enormous opportunities to produce different types of biofuels from sorghum-based biomass. First, composition, structure, and uses of different sorghum plant parts (stalks, leaves, grain, starch, and oil) are briefly described. Then, we present and discuss in detail different pretreatment methods (physical, chemical, physicochemical, and biological) that enable the utilization of sorghum biomass for biofuel production. There have been significant improvements in different pretreatment methods and their efficiencies for biofuel production. The best methods will depend on the availability of facilities and resources. Further investigations should be directed towards developing simpler, more effective and energy-saving technologies for biofuel production from sorghum-based feedstock. Since most of the sorghum pretreatment processes generate inhibitors of microbial growth and reduce product yield, the need for a detoxification stage is emphasized. Future research should focus towards developing the appropriate pretreatment strategies and overall process integration for improved processing of biomass and final biofuel production. A smart combination of two or more pretreatment methods for efficient biomass processing, selective recovery, and reduced inhibitor formation should be researched. A strong collaboration, partnership, and support from industry, private sector, and public sector will be required for successful implementation and establishment of large-scale biofuel production plants from different bioenergy feedstocks