• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.79-84
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• 2015

This study was carried out in order to develop an economical and convenient way to improve storability of sweet persimmon 'Fuyu'. Natural porous materials (bamboo active carbon, chaff charcoal, and Ge-lite) pouching bags were enveloped in the conventional LDPE (low density polyethylene) package during room temperature and low temperature storage. The changes of soluble solids content, flesh firmness, flavor, decay, and softening of sweet persimmon were investigated in the 1- or 2-week intervals. The LDPE packaging with bamboo active carbon treatment was confirmed to maintain longer storability and higher quality than the LDPE packaging only. This method is expected to be applied to both of conventional and organic farming as an economical and convenient way to improve storability on long term storage and during distribution.

• Food Science and Preservation
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• v.16 no.5
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• pp.675-679
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• 2009

We investigated how Germanium (Ge) application, and the application method, affected 'Niitaka' (Pyrus pyrifolia) fruit quality in a conventional orchard. Ge-treated pears weredark yellow in color, indicating appropriate maturation. Other fruit characteristics, and weight, did not significantly differ between tests and controls. Compared to controls, fruit from Ge-treated trees had more soluble solids, a lower acid content, and fewer stone cells, which reduced fruit chewiness. Ge-treated trees showed a higher Ge concentration in fruit but a lower calcium (Ca) concentration. Other fruit mineral nutrients, includingP, K, and Mg, did not differ in level between Ge-treated fruit and controls. Ge-treated fruit showed greater firmness and a heavier specific weight during 6 months of storage, compared to control fruit. Therefore, Ge treatment reduced fruit pithiness, which can be a problem in 'Niitaka' pears. Overall, there was no significant difference between Ge-treated and control fruit qualities, but a combined Ge treatment (fertilization plus foliar application plus trunk injection) slightly improved fruit quality.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.48-53
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• 2001

The study was conducted to examine the storage potential of recently developed oriental pears, 'Kamchun' and 'Chuhwang'. The content of soluble solids of 'Kamchun' pears was above 13.2% but the acidity was below 0.082% at three harvest dates. Although skin browning disorder did not occur in 'Kamchun', about 40% of fruits were affected by core breakdown especially when harvested after middle of October. In contrast, flesh browning was also observed in early harvested fruit. Flesh firmness of 'Chuhwang' was higher than that of 'Kamchun' at harvest as well as after storage. The acidity of 'Chuhwang' was constantly higher than that of 'Kamchun'. Severe skin browning (approximately 80%) occurred in 'Chuhwang' pears regardless of harvest dates. Also, more flesh browning disorder was found in fruit harvested early in the season. Further research is required to determine the optimum harvest date of both cultivars and postharvest managements to inhibit the physiological disorders.

• Journal of the Korean Society of Food Culture
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• v.31 no.6
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• pp.597-604
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• 2016

This study was performed to investigate the quality characteristics of lotus root tea (LT) prepared with Gardenia jasminoides powder (GLT) and Rubus coreanus Miquel powder (RLT). The proximate compositions, physicochemical properties, mineral contents, and sensory evaluations of samples were measured. GLT sample showed higher contents of crude protein, crude fat, crude ash, and moisture (p<0.001) as well as pH (p<0.001) compared to LT and RLT. In terms of color, lightness (L) and yellowness (b) of GLT were the highest among the samples, whereas redness (a) of GLT was the lowest. The results of mineral analysis showed that the mineral contents of K, Ca, and Fe of LT were the highest, whereas the content of Mg of GLT was the highest. The results of browning color intensity of all samples showed that LT had the lowest. GLT showed higher contents of water soluble solids than LT and RLT. In the sensory evaluation, the scores of color, flavor, aftertaste, feeling of throat, and overall preference of LT and GLT were significantly higher than those of RLT. From the findings, this study suggests that addition of Gardenia jasminoides powder was effective for preparation of lotus root tea in the aspects of consumer acceptability.

• Food Engineering Progress
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• v.15 no.1
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• pp.80-84
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• 2011

The effects of incorporating hot water extract of Schisandra chinensis fruit on the physicochemical and sensory properties of Sikhe were investigated. The extract was incorporated at 5 levels (0, 10, 20, 30, 40, and 50%, v/v) by replacing equivalent amount of distilled water. The pH decreased while the soluble solids content increased significantly with the increase in the extract replacement (p<0.05). Redness ($a^*$-value) increased significantly as the extract concentration increased (p<0.05); on the other hand, lightness ($L^*$-value) and yellowness ($b^*$-value) did not show any direct relationships with the extract replacement. Color, sour taste, and sweet taste except for Sikhe flavor were distinctively classified by the sensory analyses (p<0.05). Correlation analysis indicated that level of extract incorporation was well-correlated with all the physicochemical and sensory properties studied except for $L^*$- and $a^*-$ value. Finally, the consumer test based on Friedman-type statistic, suggested that 10% incorporation of the hot water extract of Omija fruit was recommended for making Sikhe.

• Journal of the Korean Society of Food Culture
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• v.37 no.6
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• pp.555-563
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• 2022

The purpose of this study was to confirm the quality characteristics of distilled soju with different rice pretreatment processes. The non-steamed fermentation method is a technology that uses starch to produce saccharification and alcohol without going through the steaming of raw materials. It has advantages such as reduction of manpower and cost, prevention of nutrient loss, and minimization of waste water. In this study, rice used were non-steamed and pulverized 'Baromi2', nonsteamed and steamed 'Samgwang', and puffed rice. As the fermenting agent, koji, modified nuruk, N9 yeast, and purified enzyme were used, and lactic acid was added to prevent contamination during fermentation. The amount of water was 300% in total, and after the first watering, 5 days after fermentation, the second watering was carried out. As a result of the study, it was confirmed that the non-steamed fermentation method using 'Baromi' was superior to the existing fermentation method in terms of temperature during fermentation, final alcohol content, soluble solids, and pH. By expanding the stability of the production technology of non-steamed fermentation technology, product quality improvement can be expected.

• Journal of the FoodService Safety
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• v.5 no.1
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• pp.30-39
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• 2024

Rice, nuruk, and water are the main ingredients to prepare takju, a traditional Korean liquor. Takju quality varies depending on the type of ingredients and fermentation temperature. In the current study, different combinations of nuruk (SH, JJ) and rice (glutinous rice, non-glutinous rice) were fermented at different temperatures (20, 25℃) and analyzed for quality characteristics over the fermentation period of 10 days. Regardless of the temperature, higher soluble solids (27.1~29%) were measured in the takju prepared with glutinous rice compared to non-glutinous rice. And acidity increased from 0.03% to 1.1% to all takju fermented at both 20 and 25℃, and, higher acidity was measured in the takju prepared with JJ nuruk. The color value of lightness (L) decreased from 57.9 to 23.9. Alcohol content was less than 15.5% in glutinous rice takju and less than 12.3% in non-glutinous rice takju. Total bacteria count (7~8 Log CFU/mL) and lactic acid bacteria count (4~7 Log CFU/mL) increased in different takju. However, the very high yeast count was recorded in takju prepared from SH nuruk compared to takju prepared from JJ nuruk at 0 day of fermentation. A sharp decline (84.92~98.57%) of yeast was observed just after the 1st day of fermentation which gradually reduced to lowest at 4th day of fermentation. No yeast was observed at 6th day fermentation and onwards. These results indicate that the raw materials, especially rice and nuruk, affect the physiochemical properties of takju.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.973-981
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• 2022

'Shine Muscat' (Vitis labruscana Bailey x Vitis vinifera L.) grapes recently have been greatly favored in Korea, and as of 2022, account for 38.6% of the total grape market in Korea. However, there is a lack of research on post-harvest quality control appropriate to the unique characteristics of 'Shine Muscat'. In order to continuously increase domestic demand and exports in the future, it is essential to establish proper postharvest techniques. Essential oils have remarkable potential as biologically active and environmentally friendly antiseptics for the fruit industry. The objective of this study is to evaluate the effects of essential oils and aroma constituent treatment on fruit quality attributes of 'Shine Muscat' grapes in order to extend fruit quality during a simulated export period. A cluster of 'Shine Muscat' grapes was placed in a newly developed paper box container, and treated with rosemary essential oil, thyme essential oil, and linalool, along with an untreated control. The results showed no significant effect on fruit quality indices, such as cluster weight loss, berry firmness, soluble solids content, titratable acidity, sugar acid ratio, and color change, but showed a positive effect on the alleviation of berry shatter compared to the untreated control. In addition, rosemary oil treatment reduced the proportion of unhealthy berries. Therefore, the results indicated that the newly developed packaging container along with certain essential oil treatment could be applied as a promising packaging material for table grape export.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.75-81
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• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.

• Food Science and Preservation
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• v.16 no.6
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• pp.977-984
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• 2009

Campbell Early grapes, the major grape variety in Korea, contain 13 - 15% (w/v) sugar, which is lower than that appropriate for fermentation of red wine. Therefore, chaptalization with sucrose is usually used to increase the sugar level to an extent adequate to produce a wine containing about 12% (v/v) alcohol. In the present study, fermentation of freeze-concentrated Campbell Early grape juice at $25^{\circ}Brix$ was investigated using several industrial wine yeasts including Saccharomyces cerevisiae OC2, S. cerevisiae Fermivin, and S. cerevisiae W-3. During fermentation, changes in the levels of soluble solids, alcohol, total acid, and yeast viable counts were investigated. Alcohol content reached maximal levels after 9 days of fermentation, and was 12.6% (v/v) when the Fermivin strain was used and 13% (v/v) when each of the OC2 and W-3 strains was used. No significant between-strain difference was found, except for slightly slower alcohol production and sugar consumption, and a higher total acid content when strain OC2 was used. Changes in the yeast viable counts were similar during fermentation. The physicochemical characteristics of Campbell Early wine prepared using freeze-concentrated juice were investigated by measuring the levels of total phenolic compounds, organic acids, acetaldehyde, and minor alcohols and assessment of color values. Similar levels of soluble solids and total phenolic contents were observed in wines fermented by the three different strains, but a higher level of total acid was noted in OC2-fermented wine and a lower level of alcohol in Fermivin-fermented wine. The highest level of malic acid and the lowest level of lactic acid were detected in Fermivin-fermented wine. Although the wines showed variable levels of acetaldehyde and minor alcohols, the concentrations of these materials were much lower than those mandated by legal regulations promulgated by the Korean National Tax Service. Red and violet colors in OC2-fermented wine were darker than those of W-3-fermented wine. In sensory evaluation, W-3-fermented wine obtained the highest scores for color and flavor. However, the best taste score was reported for the OC2-fermented wine, whereas Fermivin-fermented wine was awarded the highest score in overall acceptance.