Optimized Roasting Conditions of Germinated Wheat for a Novel Cereal Beverage and Its Sensory Properties

Abstract

The objective of this study was to investigate the possibility of using germinated wheat as a nutritionally improved novel cereal beverage. To enhance the health-related functionality of a germinated wheat beverage (GWB), the roasting time and temperature of germinated wheat were optimized using a central composite design and response surface methodology. The optimum roasting conditions were determined as roasting temperature of 180 °C and roasting time of 44.56 min, resulting in maximum total flavonoid content (0.74 mg CE/g), total phenolic content (1.95 mg GE/g), 2,2-diphnyl-1-picrylhydrazyl (DPPH) radical scavenging activity (5.10 μM TE/g), Trolox equivalent antioxidant capacity (9.45 mM TE/g), and γ-aminobutyric acid content (2.25 mg/g). The germinated wheat roasted with optimum conditions was prepared in two types of GWB (hot and cold), and the sensory characteristics were tested by consumers (n = 102). The cold GWB showed relatively high preferences compared to hot GWB in appearance, odor, taste, and overall acceptabilities. In the intensity results of the sensory properties of GWB, the cold GWB tended to have stronger browning, grain odor, and nutty taste than the hot GWB. Conclusively, this study showed that optimizing the roasting conditions of germinated wheat could achieve desirable sensory properties and consumer acceptance while improving the health-related functionality of GWB.

Wheat and Wheat-Derived Beverages: A Comprehensive Review of Technology, Sensory, Biological Activity, and Sustainability

“…Roasting germinated cereals also creates a unique flavor profile, which has been attributed to the elimination of ethanoic acid, acetic acid, and other undesirable volatiles generated during germination ( Kim et al, 2021 ). Two methods of beverage preparation, infusion, and boiling, were compared and found to differ significantly in sensory attributes and consumer acceptability ( Aung et al, 2022b ). A hot beverage is prepared by infusing roasted germinated wheat in hot water (approximately 100°C).…”

“…Specific roasting conditions, including time, and temperature, significantly affect the components present in grain products. Researchers have therefore focused on studying how roasting conditions cause changes in the physicochemical characteristics, structural profiles, bioactive components, antioxidant activities, and bioavailability of grain components ( Aung et al, 2022b ).…”

“…Overall, roasting aids in enriching health-promoting ingredients in beverage formulations and can produce desirable flavors and aromas. Roasted wheat is generally prepared by infusion or brewing with water and can be served either hot or cold ( Aung et al, 2022b ; Patra et al, 2023 ). Roasted wheat prepared by infusion and boiling methods exhibit strongly different flavor profiles and nutraceutical characteristics.…”

“…This study suggested that overall perception can be improved by spontaneous fermentation. More recently, the consumer acceptability of hot and cold roasted-germinated wheat beverages was described using different sensory attributes －i.e., appearance, odor, taste, and overall acceptability－ using a 9-point hedonic scale ( Aung et al, 2022b ). According to these authors, cold beverages generally showed higher sensory attributes and consumer acceptability than hot beverages.…”

Neuroimaging Approach: Effects of Hot and Cold Germinated Wheat Beverages on Electroencephalographic (EEG) Activity of the Human Brain

“…A beverage prepared from roasted germinated wheat ( Triticum aestivum L.) is a recently developed functional beverage [ 1 , 2 , 3 ]. Previous reports have described hot and cold germinated wheat beverages containing abundant volatile compounds, amino acids, and phenolic compounds.…”