This study was conducted investigate antioxidant activities and quality characteristics of castella cake with ethanolic extract from Seoritae (black soybean) to potential suggestion to develop natural functional source for baking.
Seoritae extract (SE) was prepared by 95% edible ethanol. AA of SE was assayed by total phenolics content (TPC), ABTS radical scavenging activity (ARSA), DPPH radical scavenging activity (DRSA) and ferric reducing antioxidant power (FRAP). TPC of SE was 2.18mg/g. AA results of SE on all the assay were shown tendency dependent on sample concentration ranged from 31~1000㎍/ml. ARSA of SE was showed 6.1~76.2%. DRSA of SE was showed 7.1~64.9%. FRAP was measured optical density at 593nm. FRAP of SE was 0.1~0.8 at 593nm.
Quality characteristics such as appearance, color values, and texture properties as TPA(Texture Profile Attribute) of castella cake with ethanolic extract from seoritae investigated. The sensory attribute castella cake were evaluated and used as parameters for determining the optimum additional ratio of SE. Microbial (aerobic bacteria, coiform, and mold) changes determined during storage for 10 days. Futhermore, occurrence of mold of castella cake in environmental condition with high relative humidity was observed during storage.
Lightness of color value of castella cake wasn't show significant difference between control sample prepared without SE and sample prepared with added SE ranged from 1% to 3%. Yellowness of color value decreased with increasing additional ratio of SE. Texture properties of castella cake investigated as TPA from parameter with hardness, springiness, chewiness, cohesiveness, and resilience. There wasn't show consistent tendency on all parameter. Hardness and chewiness showed highest value on sample prepared with added 2% and 3%. There wasn't show significant difference on springiness, cohesiveness and resilience among all sample.
Microbial count such as aerobic bacteria and mold of castella during storage cake decreased with adding SE and increasing additional ratio of SE. Coliform wasn't detected all sample. Mold occurred after storage for 3 days in 93% relative humidity and spreaded widely after storage for 4 days on contro sample. However, mold weren't occurred on sample adding SE ranged from 1% to 5%. Sensory evaluation suggested that color, flavor, texture, taste and overall acceptability with the castella cake sample were decreased by adding SE.