• Food Science and Preservation
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• v.13 no.3
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• pp.304-309
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• 2006

In order to examine the antimicrobial effect on dairy processing facilities and products, Prunus mume extinct (PME) was applied to the pilot plant system of dairy industry and yogurt, PME showed thermal and pH stability in the wide spectrum of temperature ($40{\sim}150^{\circ}C$) and pH ($4{\sim}10$) and remarkable antimicrobial activities against dairy spoilage microorganisms. As the result of aseptic treatment of dairy processing facilities with PME microbial colony including coliform bacteria was not detected canpore to those detected in the control. In the level of PME concentration which inhibit the growth of putrefactive microorganisms we could produce yogurt with good scores of sensory evaluation.

• Food Science and Preservation
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• v.13 no.3
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• pp.351-356
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• 2006

This study was carried out to investigate the change of functional component and volatile flavor components from garlic for which both were treated with protopectinase (PPase) and mechanical maceration during storage period. Alliin content of gallic suspensions macerated mechanically were 11.0 mg/g at 0 day and 6.6 mg/g at 24 day. Whereas alliin content of garlic treated with PPase were 8.5 m/g at 0 day and 7.0 mg/g at 24 day. Importantly, over 40% of alliin which is the most unstable component during the mechanical maceration remained with an intact form for 24 day after the enzymatic treatment. The flavor component from gallic suspensions were extracted by solid-phase microextraction (SPME) and were analyzed and identified by gas chromatography (GC) and chromatography/mass spectrometry (GC/MS). The number and concentrations of flavor components of gallic macerated mechanically were increased during storage period, and total 18 kinds of flavor compounds were identified. Thus, the PPase treatment of garlic could be a better choice for preparation of the highly valuable and functional processed food as well as for prolonging the preservation period.

• Food Science and Preservation
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• v.23 no.4
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• pp.522-529
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• 2016

Clean rice is useful to save time and labor force against washing rice in the household. Nevertheless the quality characteristics of the rice were not established well since the quality characteristics of the rice depend on types of the processing system. The aims of the current study were to understand the quality characteristics of clean rice prepared from the dry, semi-dry, and wet types of processing systems, and to suggest the appropriate processing system for production of clean rice. Here, we found that the quality of clean rice was improved with the increasing whiteness of rice by the dry type, although the whiteness of rice should be below 42 to satisfy 16.0 NTU of the turbidity for higher head rice ratio. Also, both the semi-dry and wet type systems showed higher ratio of head rice than the dry type system at below 16.0 NTU of the turbidity. These results imply that the wet type is more suitable for the place where rice is consumed fast, and the semi-dry type is more proper for long term storage of rice.

• Food Science and Preservation
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• v.23 no.3
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• pp.301-309
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• 2016

The objective of this study was to investigate physicochemical and antioxidant characteristics of immature flat persimmon during 7 heat treatment aging steps. The pH decreased, and hence, acidity increased with aging. Hunter L value decreased with aging. The a value rapidly increased until step 3, whereas the b value decreased. Fructose content decreased while glucose contents slightly increased during aging. Hardness, chewiness and gumminess rapidly decreased, indicating softening in texture, but it was negligible after aging step 3. Phenolic compounds including gallic acid and homogentisic acid were detected at step 3 and then gradually increased with aging. However, contents of flavonoid and tannin were much higher in step 1 sample than others. The antioxidant activities observed by DPPH, ABTS, and FRAP assay were the highest at step 1 possibly due to the higher levels of flavonoids and tannin acid in the step 1 sample.

• Food Science and Preservation
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• v.23 no.3
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• pp.310-318
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• 2016

This study was performed to investigate changes in the quality characteristics and chemical compounds in garlic shoots by blanching for different time (0, 0.5, 1, 2, 3, and 4 min). The color (L, a, and b values), texture profile (hardness, springiness, chewiness, gumminess, and cohesiveness), total vitamin C, total sugar, total polyphenol and flavonoid, chlorophyll a and b contents, total pyruvate and thiosulfinate contents of the blanched garlic shoots were examined. As the blanching time increased, the L and b values decreased, while the a value increased. Hardness, chewiness, springiness and gumminess of the blanched shoots were significantly lowered with the increasing blanching time. Vitamin C content of raw garlic shoot was 1.62 mg/100 g while that of the blanched garlic shoots was 0.16~0.24 mg/100 g, implying vitamin C loss into blanching water and destruction by heat. The total sugar and polyphenol contents were fluctuated during blanching, but over 75% of their initial levels were retained under all blanching conditions. The total flavonoid contents increased as the blanching time increased. The chlorophyll a content did not show significant change with blanching time, but the chlorophyll b content significantly decreased. These results suggest that blanching for 2 min could be the best for retaining beneficial compounds and desirable quality of garlic shoot.

• Food Science and Preservation
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• v.16 no.2
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• pp.139-146
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• 2009

Whole and stem-off cherry tomatoes were packaged using perforated films(LF05, LF10, LF20, and LF40). Gas composition(ethylene, $O_2$, and $CO_2$), firmness(compression and penetration force), color, brix degree, acidity, and total microbial counts were assessed during storage at $10^{\circ}C$ and 85% relative humidity. Gas composition varied with film gas permeability, indicating that modified atmospheric(MA) conditions were achieved. Firmness fell during storage; samples packed using LF05 showed the lowest firmness, corresponding to low gas transmission conditions. L(lightness) and a(redness) values respectively decreased and rose slightly with increasing storage time, but the b(yellowness) values fell notably. Film permeability significantly affected acidity and soluble solid levels. When LF40 packaging was used, acidity and brix scale changes were similar to those seen after PET container packaging. Total microbial counts increased with time after packaging in most films, and pretreatment differences were not significant. Microflora varied between stem on/off tomatoes. Skin wrinkling and juice appearance were common in tomatoes stored in PET containers and LF films of low gas permeabilities(LF05, LF10, and LF20). White molds were partially found on stem-on tomatoes stored using packaging systems. When film packagings were compared, LF40 was optimal, permitting minimal pretreatment yet offering maximal sanitation.

• Food Science and Preservation
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• v.21 no.3
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• pp.357-364
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• 2014

The quality improvement of the boiled-dried anchovy treated with acidic electrolyzed water (AEW) was investigated. The L value was higher in the anchovy treated with AEW than in the control. Moreover, its ${\Delta}E$ value was 5.08 higher than that of the control. The lipophilic browning degree was also higher than the hydrophilic degree. The degrees of calcium absorption of the control and anchovy treated with AEW were 10.77% and 12.61%, respectively. During their storage in the different conditions (five weeks in $20^{\circ}C$, ten weeks in $4^{\circ}C$, and five months in $-20^{\circ}C$), the lipophilic browning degree of the anchovy treated with AEW was significantly lower than that of the control at the $20^{\circ}C$ storage. The volatile basic nitrogen (VBN) content gradually increased as the storage period increased. During the $20^{\circ}C$ storage, the content of the anchovy treated with AEW was lower than that of the control. The lipid peroxide contents increased with the storage periods, regardless of the temperature, but the content of the anchovy treated with AEW was lower than that of the control. These results indicate that AEW treatment can improve the color quality of boiled-dried anchovy and reduce its VBN and lipid peroxide contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.695-699
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• 2012

The objective of this study was to set the optimal extraction condition of flavonoids from onion peels as a by-product generated from the onion industry without suitable processing. Four independent variables, affecting extraction conditions, which are solvent concentration ($X_1$), extraction temperature ($X_2$), pH of the solvent ($X_3$), and solvent ratio to onion peel ($X_4$) were optimized using response surface methodology (RSM). A model equation obtained from RSM is 0.772 of R-square and 0.278 of lack of fit (p>0.05) for the optimal extraction conditions. From the ridge analysis, the conditions flavoring the highest extraction were solvent concentration (v/v) of 70%, extraction temperature of $40^{\circ}C$, extraction solvent pH of 5.3, and a solvent ratio to onion peel ratio of 1:63 (w/v). The flavonoid content obtained under optimal conditions showed 302.63 mg/g, which is 1.12 times higher than the prediction value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1025-1029
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• 2008

Fresh green tea leaf extracts were prepared by different enzyme treatment conditions, such as concentration, treating time and treating temperature using complex enzyme, Rapidase TF, and then extracted for 30 min at $80^{\circ}C$ to investigate their physicochemical properties. The results showed that free sugar content in every sample tended to increase, especially glucose content was increased up to 7.25 times compared to the control. Total amino acid was barely affected by the enzyme treatment and caffeine content was increased with reaction temperature. Total polyphenol and total catechin content was increased according to the amount of enzyme added and reaction temperature. Regardless of enzyme treatment conditions, composition of catechins were epigallocatechin, epicatechin, epicatechin gallate and epigallocatechin gallate by descending order of the content. Gallic acid content increased up to 0.04% and $45^{\circ}C$ with no further significant changes thereafter. From the results above, we could conclude that a simple and new method to extract green tea materials directly from fresh green tea leaves with improved extract ratio may be introduced by adding $0.08{\sim}0.1%$ of Rapidase TF to heat treated fresh green tea leaves and keeping temperature at $37{\sim}45^{\circ}C$ for $180{\sim}240\;min$ in order to skip existing complicated procedures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.412-417
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• 2015

This study was carried out to investigate the effect of steam-drying method on physicochemical properties and antioxidant activities of Alliun hookeri root (AHR). Moisture, crude protein, crude fat, and crude ash contents of raw and steam-dried AHRs were 10.91~14.15%, 11.14~13.49%, 0.83~3.02%, and 7.55~8.98%, respectively. Sulfur contents of steam-dried AHRs were 2.0 and 2.2 times lower than that of raw AHR (0.51%), respectively. pH and total sugar contents of AHRs were reduced by steam-drying, whereas titrate acidity and browning intensity were increased. The L and b values of AHRs in Hunter's value were also reduced, but a value was increased by steam-drying. Among hot water extracts from raw and steam-dried AHRs, four times steam-drying showed the lowest $EC_{50}$ values (0.44, 9.01, and 0.48 mg/mL, respectively) in DPPH radical assay, ABTS radical assay, and reducing power, whereas four times steam-drying had the highest total phenolic content ($34.47{\mu}g/mg$) and browning intensity (2.05 and 0.20 at 280 and 420 nm, respectively). The antioxidant activities of hot water extracts from raw and steam-dried AHRs were closely correlated with their total phenolic contents and browning intensity, showing coefficient of determination ($R^2$) values higher than 0.87. From the results, we suggest that steam-drying method could be used as an effective process for increasing the antioxidant activity of AHR.