• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.226-232
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• 2004

Dilution concentration of watermelon juice, concentrations of added sugar, citric acid, and vitamin C, sterilization temperature and time, and natural color extracts were evaluated to determine optimum conditions for watermelon beverage production. Optimum dilution concentration of watermelon juice and optimum content of soluble solid were 40% and $12^{\circ}Brix$, respectively. Addition of 0.5 and 0.3 g/L or 1.0 and 0.3 g/L citric acid and vitamin C gave optimum sensory quality. Sterilization of watermelon beverage at above $70^{\circ}C$ decreased redness. Sterilization at $60^{\circ}C$ for 10 to 30 min or at $70^{\circ}C$ for 10 min achieved best sensory quality. Addition of 20 g/L raspberries gave best sensory quality among raspberries, omija, and borage. Hot water was better than alcohol for extraction of natural color. Ratio of extracts for optimum sensory quality was 7 : 3 for extract of 20 g raspberries/L : extract of 30 g omija/L.

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.111-119
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• 2004

A new type of drinkable yoghurt was prepared to develop a functional yoghurt. Skim milk containing 0.4-1.0％(w/v) water extract of omija(Schizandra chinensis Baillon) was fermented by the mixed strains of Lactobacillus acidophilus and Streptococcus thermophilus. Quality characteristics of the drinkable yoghurts were evaluated in terms of compositions, keeping-quality(pH, titratable acidity, number of viable cells) and sensory properties. The drinkable yoghurts added with water extract of Schizandra chinensis were composed of 2.92-3.03％ protein, 9.98-10.23％ lactose, 0.81-1.08％ fat, 16.21-16.64％ total solid, and 14.57-15.17％ solid-not-fat. The L values(brightness) were significantly lower in the yoghurts containing water extract of Schizandra chinensis than that of the control which had no water extract of Schizandra chinensis, while the a values(redness) and b values(yellowness) were significantly higher than those of the control. The pH, titratable acidity and number of viable cells of the lactic acid bacteria of all yoghurts were not changed during the storage at 4$^{\circ}C$ for 15 days, while the pH and titratable acidity were remarkedly changed during the yoghurts stored at 20$^{\circ}C$ for 15 days. The drinkable yoghurts containing 0.4％(w/v) water extract of Schizandra chinensis added 15％(w/v) oligosaccharide, or 0.6％(w/v) water extract of Schizandra chinensis added 20％(w/v) oligosaccharide had the highest sensory score in taste and overall acceptability among the treatments. From the results, Schizandra chinensis was a useful natural additive with the bioactive effect by provision of a acceptable physicochemical and sensory properties in the drinkable yoghurt.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.198-203
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• 2007

Extracts from Schizandra chinensis Baillon (Korean name: Omija) were tested for antioxidant and their inhibitory activities of ${\alpha}-amylase$ and ${\alpha}-glucosidase$. Total contents of phenolics were found as 4.35 mg/g (water extract)${\sim}$6.35 mg/g (60% ethanol extract). Electron donating ability (EDA), ABTS [2,2'-azinobis(3-ethyl-benzothiaznoline-6-sulfonic acid)] radical decolorization, antioxidant protection factor (PF) and thiobarbituric acid reactive substance (TBARS) were measured for the antioxidative activity of the extracts from S. chinensis. The water extract were determined as 97.5% at 200 ${\mu}g/ml$ while the activity of 60% ethanol extract were 96.2% at 200 ${\mu}g/ml$ in EDA. The 60% ethanol extract showed higher antioxidant activity than water extract when evaluated by ABTS radical decolorization, antioxidant PF and TBARS. ${\alpha}-Amylase$ inhibitory activity of water extract was similar with that of 60% EtOH extract. ${\alpha}-glucosidase$ inhibitory activities of water extract (97.4%) was higher than that of 60% ethanol extract (84.5%) at 200 ${\mu}g$/ml. The water extract from S. chinensis did not show an antimicrobial activity against Helicobacter pylori, but the 60% ethanol extract showed high antimicrobial activities such as 23 ${\pm}$ 1.6 mm of clear zone in 200 ${\mu}g/ml$ of phenolics. The result suggest that the water and 60% ethanol extract from S. chinensis will be useful as natural antioxidants and functional foods.