• Korean Journal of Food Science and Technology
• /
• v.31 no.2
• /
• pp.448-457
• /
• 1999

Citrus fruits are consumed worldwide due to their unique flavor and nutrition value. It is necessary to remove the haze material as well as to minimize the loss of major compounds such as organic acids, sugars, and ascorbic acid in membrane processes for clarification of juice. The objective of our research was to select the best membrane among one surface filter (Whatman No.4) and five microfiltration filters (GF/A, GF/D, GF/F, Gelman, and SM). Tangerine fresh blended with three times of water was partially clarified with 170 mesh followed by prefiltration in a Samduck filtration system. The best membrane was selected by measuring the amounts of major compounds in the permeates as well as the flux which were statistically analyzed with SAS program. The foulants on the membrane surface were observed by SEM. The flux of GF/A and GF/F decreased with time at probability 0.10. Gelman, SM, and GF/D maintained the stable flux. Gelman showed the highest total scores including nutritive value (the amounts of citrate, malate, and ascorbic acid) and purchasing need (brix and color). Therefore, the microfiltration membrane process was a very effective method in tangerine juice clarification and Gelman type A/E was proved to be the best membrane among the five microfiltration membranes.

• Korean Journal of Food Science and Technology
• /
• v.35 no.3
• /
• pp.417-422
• /
• 2003

The onions are considered to be a favorable functional source of beverage because they contain much sugar and various nutrients, and they are juicy vegetable. Recently, consumers have a new trend to take functional foods with health benefits. To meet this need, this study was the basic research to establish a manufacturing process of functional onion beverage by glucose oxidase. Glucose oxidase catalyzes reaction of glucose oxidation and makes generation of gluconic acid. Kinetics of the reaction was also investigated, and maximum glucose consumption rate $(V_{max})$ of $26.1{\times}10^{-2}\;g/L{\cdot}min$ and $K_m$ of 5.84 g/L were obtained. Optimum conditions were obtained when the glucose oxidase catalyzed reaction was carried out at temperature of $25^{\circ}C$, agitation rate of 450 rpm and aeration rate of 4 vvm in a 2.5 L jar fermentor. Finally, the enzyme reactor was 10-times scaled up and a similar glucose oxidation performance was achieved in the scaled-up reactor.

• Korean Journal of Food Science and Technology
• /
• v.35 no.1
• /
• pp.7-14
• /
• 2003

Physico-chemical and sensory characteristics of six dongchimi cultivars were evaluated. Moisture and sugar contents were 94.2% and $4.30^{\circ}Brix$ for three spring radish cultivars, while 92.9% and $7.30^{\circ}Brix$ for three autumn ones. pH $(5.7{\sim}6.1)$ and acidity $(0.09{\sim}0.12%)$ did not show significant differences among cultivars. pH decreased steadily up to 21 days to reach optimum pH of 4.0. The maximum number of total lactic acid bacteria, $10^8{\sim}10^9\;CFU/mL$, was reached at pH 4.0. The final acidity of spring radishes was lower than that of autumn ones, and was proportional to the sugar content of the radishes. The firmness of spring radish decreased rapidly compared to the autumn ones. Cheongbok was found suitable for dongchimi, because its firmness level was maintained around $165.0{\times}10^3\;N/m^2$ at 35 days. Sensory evaluation revealed 96371 among spring radishes and cheongbok among autumn radishes scored high in firmness, chewiness, flavor, and overall acceptance. These results suggest that autumn radishes are suitable for dongchimi fermentation with cheongbok being the best among the cultivars.

• Korean Journal of Food Science and Technology
• /
• v.22 no.7
• /
• pp.748-752
• /
• 1990

This paper was investigated to elucidate the nitrite-scavenging ability of roasted-barley extracts. Roasted-barley extracts exhibited nitrite-scavenging ability. The nitrite-scavenging ability of roasted-barley extracts showed pH-dependent, and did the highest at pH 1.2 and the lowest at pH 6.0. The roasting temperature and time of barley examined influenced the nitrite-scavenging ability of roasted-barley extracts. The water soluble fraction obtained from barley roasted at $230^{\circ}C$ for 90 min showed higher the nitrite-scavenging effect than the others. Ethanol soluble fraction which is further fractionated from water soluble fraction was most effective in nitrite-scavenging.

• Food Science and Preservation
• /
• v.13 no.6
• /
• pp.740-748
• /
• 2006

The Chunma (Gastrodia elata Blume) requires a simple pre-treatment, due to inconvenience or preservation, toxicities, and pungencies in intact state. Various drying conditions were examined to establish the physicochemical properties of Chunma by the response surface methodology (RSM). Weter activity and total phenolic acid contents of Chunma dried extracts were optimal at $79.56^{\circ}C$ and $79.64^{\circ}C$ for 7.17 hr and 8.74 hr, respectively, for their characteristics. Electron-donating ability and nitrite-scavenging activity were optimal at 79.79 and $7.99^{\circ}C$ for 8.57 and 8.07 hr. We generated a regression equation for each variable and then superimposed the optimal condition in acquiring values for each frying process factor, physicochemical properties, resulting in that the optimal drying condition was at $75{\sim}80^{\circ}C$ for $8{\sim}9 hr$.

• Food Science and Preservation
• /
• v.22 no.3
• /
• pp.345-352
• /
• 2015

This study was monitored the quality characteristic of the hyssop-rice drink added using hyssop (Hyssopus officinalis) and rice. AFter operational parameters including amylase content ($X_1$, 1~5 mL), saccharification time ($X_2$, 10~18 hr) and hyssop content ($X_3$, 1.0~3.0 g) were monitored, these results were analyzed using a response surface methodology for the determination of the optimum conditions (Brix, Hunter's color and organoleptic properties). Maximum conditions of Brix for the hyssop-rice drink were 0.96 mL of amylase, 14.93 hr of saccharification time and 2 g of hyssop. Maximum conditions of Hunter's color b were 1.90 mL of amylase, 16.64 hr of saccharification time and 2.51 g of hyssop. Maximum conditions of organoleptic color were 4.60 mL of amylase, 15.66 hr of saccharification time and 1.57 g of hyssop. Maximum conditions of organoleptic aroma were 3.46 mL of amylase, 10.79 hr of saccharification time and 1.45 g of hyssop. Maximum conditions of organoleptic taste were 3.67 mL of amylase, 17.64 hr of saccharification time and 1.76 g of hyssop. Maximum conditions of overall palatability of the hyssop-rice drink were 3.73 mL of amylase, 13.66 hr of saccharification time and 1.85 g of hyssop.

• Food Science and Preservation
• /
• v.19 no.5
• /
• pp.703-711
• /
• 2012

This study was conducted to investigate the quality and organoleptic properties of dehydrated onions with steaming and heating. Sliced onions were treated as follows: steaming time ($X_1$, 5~25 min); drying temperature ($X_2$, $55{\sim}70^{\circ}C$) and drying time ($X_3$, 4~20 hr). All the variables were modelled and analyzed using a central composite design and response surface methodology (RSM). The coefficients ($R^2$) of the water content and water activity model induced from RSM were 0.9514 (p<0.01) and 0.9455 (p<0.01), respectively. The water content and water activity were affected by the drying temperature and time. The $R^2$ on the models of Hunter's L, a, b values were 0.9419 (p<0.05), 0.8818 (p<0.01) and 0.9360 (p<0.01), respectively. Hunter's L, a, b values were affected by the drying temperature and time, but Hunter's b value was not affected by the steaming time. In addition, the $R^2$ on the models of overall palatability was 0.8867 (p<0.05). The maximum palatability response was 5.92 when the steaming time was 13.14 min, the drying temperature was $63.11^{\circ}C$ and the drying time was 14.49 hr.

• Food Science and Preservation
• /
• v.19 no.5
• /
• pp.681-687
• /
• 2012

The purpose of this study was to evaluate the quality properties of muffin added with different concentration (0, 1, 3, and 5%) of rice bran. The results indicated no significant difference in the weight of muffins with different concentration of rice bran. The moisture content of the muffin decreased with longer storage time. The moisture content of the muffin to which 0, 3, 5, and 10% rice bran were 26.62, 29.07, 30.72, and 27.53%, respectively. The muffins' hardness was higher on storage day 1 than on the initial storage day. As for adhesiveness, there was no significant difference between storage time and rice bran concentration. The springiness decreased with increasing storage time. The sensory score showed that the muffin without rice bran had a higher color and flavor than the others while the muffins with rice bran had higher taste, moistness, chewiness, and overall acceptability scores than control(0%).

• Food Science and Preservation
• /
• v.21 no.1
• /
• pp.46-54
• /
• 2014

Yellow and black soybean Cheonggukjangs (YBSC) prepared with an addition of onion (Allium cepa L.) in different contents (0, 5, 10, 20, and 30%, w/w) were manufactured, and the sensory evaluation was carried out. The optimum addition ratio of onion was determined to be 20%. Total phenolic and flavonoid contents of YBSC prepared with an addition of onion were higher than those of the YBSC prepared without an onion. In addition, YBSC prepared with an addition of onion showed higher 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activities than those prepared without an onion. Furthermore, rat blood plasma 1 hour after oral administration of YBSC prepared with an onion was more effective in suppressing the accumulation of cholesteryl ester hydroperoxide than those prepared without onion and control. These results indicated that the consumption of the YBSC prepared with onion may contribute to the antioxidant defense in vivo.

• Food Science and Preservation
• /
• v.20 no.5
• /
• pp.621-627
• /
• 2013

This study was conducted to investigate the effect of Curcuma longa L. powder (CLP) on the quality characteristics of a dumpling shell. Dumpling shell samples were prepared with wheat flour and different amounts of CLP were added to them, after which their instrumental characteristics and sensory evaluation were investigated. The gelatinization temperature of the CLP-wheat flours composite increased, whereas its initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 min and maximum viscosity all fell with the increasing CLP content, as measured via amylography. As increasing amounts of CLP were added, the L value decreased, whereas the a and b values increased. With regard to the textural characteristics, the CLP additive became harder, more cohesive and adhesive, and less springy. The DPPH free radical scavenging activity increased significantly as the CLP content increased (p<0.05). Overall, the dumpling shells with 3% CLP were preferred over the other samples, as tested via sensory evaluation.