Location: Grain Quality and Structure Research
Project Number: 3020-43440-002-037-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: May 15, 2024
End Date: May 31, 2026
Objective:
The main objective is to obtain and utilize functional ingredients from sorghum and sorghum processing byproducts for value-added food applications. The project will study oleochemicals for their structure, composition, and overall functionality when used in high-moisture and low-moisture food products.
Approach:
The first step of the project involves the extraction of oleosomes and oleoresin from selected sorghum varieties based on preliminary experiments conducted by our team. Waxy sorghum, white sorghum, burgundy and black sorghum lines as well as sorghum DDGS will be used as the substrate. In brief, oleosomes will be obtained by using suitable wet milling pretreatment and high-intensity ultrasound at pH values from 3 to 10, and subsequent phase separation and filtration. The extraction conditions will be optimized with the use of salts in combination of organic acids. Oleoresins will be obtained with serial extractions of organic solvents as well as novel ionic liquids as clean-labeled alternatives and with tunable properties. Composition of oleosomes and oleoresins will be assessed for their water content, lipid content and fatty acid composition, protein content, phenolic content using essays based on HPLC, GC-MS, and spectrophotometry. The structure of oleosomes will be characterized for their particle size, zeta potential, interfacial rheology as well as nature of molecular associations via FTIR. The antioxidant activities and related free radical mechanisms will be evaluated using electron paramagnetic resonance spectroscopy (EPR). The compositional and structural properties will be linked to their performance in food systems.
Oloesomes will be used to manufacture and improve the quality of high-moisture food products, such as nutritional and high-protein beverages, as well as gels, such as yoghurt and tofu-like food products. The physical stability of the products will be evaluated based on their resistance against phase separation via gravimetric methods and changes in particle size distribution. The textural attributes of the food products will be analyzed using a texture analyzer and rheometer, while compositional architecture and networking will be evaluated using IR microscopy coupled to an FTIR spectroscopy. A sensory panel will also be employed to assess consumer acceptability. Relationship between structural characteristics, composition and stability will be elucidated using chemometrics approaches. Oleoresins will be used to improve the quality and nutritional value of low-moisture food products, such as chocolate. We hypothesize that oleoresins can replace lecithins when used in dark chocolate manufacturing. The quality of the chocolate will be evaluated using texture analyzer, DSC, XRD, and sensory analysis. Similarly, the efficiency of oleoresins as coatings in confectionery products will be studied, along with their ability to enhance oxidative stability.
