No abstract

This study investigated the quality characteristics of cookies containing Platycodon grandiflorum powder, which is well known for its various functions and biological activity. Cookie samples were prepared by adding the Platycodon grandiflorum powder at different levels of 0%, 1%, 3% and 5%. In this study, moisture, pH, color, spread factor, hardness and sensory evaluation of cookies were examined. The results showed that the pH and moisture of cookies were decreased when more amount of Platycodon grandiflorum powder was added. Regarding the color of cookies, the L value was decreased when more amount of Platycodon grandiflorum powder was added, where as the a value and b value were increased (p<0.001, p<0.01). The spread factor of cookies generally increased as more amount of Platycodon grandiflorum powder was added, but it was not statistically significant. The hardness of the cookies decreased as more amount of Platycodon grandiflorum powder was added. Cookies containing 1% of Platycodon grandiflorum powder showed the highest scores for overall acceptability, color, taste and texture. Regarding the flavor of cookies, the control showed the highest score, and the score decreased as more amount of Platycodon grandiflorum powder was added.

γ-PGA(poly-γ-glutamic acid) is an unusual anionic polypeptide that is made of D-and L-glutamic acid units connected by amide linkages between α-amino and γ-carboxylic acid groups. γ-PGA has been isolated from many kinds of organisms. Many Bacillus strains produce γ-PGA as a capsular material of an extracellular viscous material. It is safe for eating as a viscosity element of fermented soybean products such as Chungkookjang and Natto. It is biodegradable, edible and nontoxic toward humans and the environment and its molecular weight varies from ten thousand to several hundred thousand depending on the kinds of strains used. Therefore, potential applications of γ-PGA and its derivatives have been of interest in the past few years in a broad range of industrial fields such as food, cosmetics, medicine, water-treatment, etc. In this study, a bacterium, Bacillus subtilis GS-2 isolated from the Korean traditional seasoning food, Chungkookjang could produce a large amount of γ-PGA with high productivity and had a simple nutrient requirement. Based on carbon utilization pattern and partial 16S rRNA sequence analysis, the GS-2 strain was identified as B. subtilis. The determination of purified γ-PGA was confirmed with thin layer chromatography (TLC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR) spectra, and 1 H-nuclear magnetic resonance ( 1 H-NMR) spectroscopy.

We investigated the quality characteristics of cookies made with Chungkukjang powder. Chungkukjang is a well-known nutritional supplement. Cookie samples were made by adding differrent quantities of Chungkukjang powder(0%, 4%, 8% and 12%). We examined the resulting, moisture, pH, color, spread factor, hardness and sensory evaluation of the cookies. While the moisture and, a and b value of the cookies significantly increased when more Chungkukjang powder was added (p<0.01), the pH, L value, spread factor and hardness of the cookies significantly decreased(p<0.01). Cookies containing 0% and 4% Chungkukjang powder had similar sensory evaluation score in terms of color, taste and flavor cookies made with 4% Chungkukjang powder had the highest texture and overall consumer acceptability scores.

We investigated the quality characteristics of cookies prepared after the addition of various concentration of used guava leaf powder(0%, 1%, 3%, 5%, all w/w) as a substitute for flour. In this study, as guava leaf powder concentration rose, there was a decrease in the water content level. In addition, color, spread factor, hardness and sensory evaluation of the cookies were examined. The results showed that with an increase in guava leaf powder concentration, the L value decreased significantly, while the values for a and b of cookies increased when more guava leaf power was added to cookies. The spread factor of cookies decreased, but the hardness of cookies increased significantly, as guava leaf powder concentration increased. Cookies containing 0% and 3% of guava leaf powder showed a similar sensory evaluation score in terms of color, taste and flavor of the cookies. In the case of texture and overall consumer acceptability, cookies with 3% of guava leaf powder showed the highest score.