Dae-Hoon Lee

Physicochemical properties of aromatic rice prepared using different milling recoveries and roasting procedures

향미의 도정률에 따른 색도는 도정률이 증가할수록 L값은 증가하고 a 값 및 b 값은 감소하였으며, 갈색도 및 탁도는 감소하는 경향을 나타내었다. 총 폴리페놀, amylose 및 전분 함량은 도정률이 증가할수록 각각 28.11-33.84 ㎎/100 g, 24.97-31.06 ㎎/100 g 및 68.27-73.04%로 폴리페놀은 감소하고 아밀로오스 및 전분 함량은 증가하였다. 향미의 품질 향상을 위한 로스팅 처리는 시간이 증가할수록 L 값은 감소하고 a 값 및 b 값은 증가하였다. 총 폴리페놀 및 총 플라보노이드 함량은 로스팅 처리 구간에서 각각 37.41-41.65 ㎎/g 및 21.93-22.30 ㎎/g으로 무처리구간 33.00 ㎎/g 및 20.78 ㎎/g보다 전반적으로 증가하는 경향을 나타내었다. 아밀로오스 및 전분 함량 또한 로스팅 처리를 통해 25.06-26.10 g/100 g 및 76.38-81.81%로 무처리구에 비해 증가하였다. DPPH 및 superoxide radical 소거활성 및 FRAP에서는 로스팅 처리한 향미벼에서 61.56-67.78%, 43.14-52.90% 및 0.72-0.79 mM을 나타내어 무처리 구간보다 높은 소거활성을 나타내었다. 이상의 결과에서, 향미를 20% 도정한 다음 30분 로스팅 처리로 인해 가공적성 및 항산화 활성이 증진되어 식품가공용 소재로 다양하게 활용 가능할 것으로 사료된다.

Spray-dried powder preparation of pumpkin sweet potato hydrolysates and its physicochemical properties

This study was conducted prepare spray-dried powder using pumpkin sweet potato hydrolysates and examine the physicochemical properties of the powder. The insoluble dietary fiber and soluble dietary fiber of the pumpkin sweet potato treated by enzyme were 4.17% and 2.07%, respectively. The spray-dried pumpkin sweet potato hydrolysates was manufactured via spray-drying with different forming agents: i.e., pectin 0.1%, 0.5%, 1%, and 2.0%. The moisture contents and total starches of the spray-dried powders were approximately 1.68-2.46 and 45.32-46.51%, respectively. The color of the L and a value decreased, and that of the b and ΔE value increased. The particle size and outer topology of the spray-dried powders were 37.17-42.32 μm, and its shape was generally globular. The water absorption index of the spray-dried powder (1.74-1.91) was lower than that of the freeze-dried powder (2.15). The water solubility index of the spray-dried powder, 80.75-87.61%, was higher than that of the freeze-dried powder (70.47%). The adhesion values of spray-dried powder to epithelial HT-29 cells were 2.66-6.18% of the initial cell counts, whereas freeze-dried powder showed lower adhesive ability (1.79%). The in vitro human digestibility in the spray-dried powder was 70.09% which is very effective in digestion.

Physicochemical properties and anti-wrinkle effect of polysaccharides with different molecular weights from Gloiopeltis furcata

In this study, the physicochemical properties and anti-wrinkle effect of polysaccharides with different molecular weights from Gloiopeltis furcata were investigated. Crude polysaccharides were isolated by viscozyme treatment followed by ethanol precipitation and lyophilization. Crude polysaccharides were hydrolyzed by acid (0.1 N HCl) and the molecular weight fractions were generated by centrifugal filter (<10 kDa, 10 to 100 kDa, and 100 kDa>). The yield of polysaccharides with different molecular weight fractions was 8.4-39.6%. The major constituents in molecular weight fractions were total sugar (81.37-85.82%), uronic acid (27.89-32.85 g/100 g), sulfate (33.38-39.04%), and protein (0.35-3.16%) The L, a, and b value of the 100 kDa group were decreased, but viscosity increased. The oxygen radical absorbance capacity of the 100 kDa group at 180.07 μM was the highest among groups. The protective effects of 100 kDa group at 0.5 and 5 μg/mL against H2O2-induced cytotoxicity in L132 cell were 87.34% and 103.85%, respectively. The matrix metalloproteinase-1 activity of 100 kDa group decreased in a dose-dependent manner. The pro-collagen synthesis activity of 100 kDa group at 0.05-0.5 μg/mL was 64.91-77.80%. The polysaccharides with different molecular weights from Gloiopeltis furcata investigated herein are useful as a potential candidate for cosmedical materials.