• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.469-474
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• 2006

This study was carried out to investigate the changes of physicochemical characteristics of Schizandra chinensis during postharvest ripening for 8 days at various temperatures. The juice yield of S. chinensis, which was 55.7% before postharvest ripening, was unchanged $(55.3{\pm}0.6-56.3{\pm}0.6%)$ at $4^{\circ}C$ storage, but was decreased at the level of 6 and 7% at $25^{\circ}C$ and room temperature (RT), respectively. During storage at $25^{\circ}C$ and RT, the titratable acidities of S. chinensis were the highest at $7.49{\pm}0.03$ and $7.20{\pm}0.03%$ after 6 days of postharvest ripening, respectively. During storage at $25^{\circ}C$ and RT, the soluble solid content of S. chinensis was increased from $8.2{\pm}0.1%$ at initial stage to a peak of $12.2{\pm}0.15%$ at 6-day storage, after which it decreased. L values (lightness) of S. chinensis were increased in all treatments during storage, and a values (redness) of $25^{\circ}C$ and RT treatments were increased from 5.04 initially to 6.77 and 7.65 at 8-day storage, respectively. The major free sugars of S. chinensis were fructose (0.55%), glucose (0.56%), and sucrose (0.50%). During storage at $25^{\circ}C$ and RT, the fructose and glucose contents were continually increased with increasing storage period, while the sucrose contents decreased after 6-day storage. Major non-volatile organic acids of S. chinensis were succinic (1.21%), citric (0.17%), and malic (0.07%) acids. Changes in the organic acids contents of S. chinensis at various temperatures showed a similar tendency to that of the free sugars. We estimated that the best conditions for the postharvest ripening of S. chinensis were 8 days at $4^{\circ}C$ storage, and 6 days at $25^{\circ}C$ and RT.

• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.386-394
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• 2019

Rehmannia glutinosa, one of the major medicinal crops in Korea, can be classified into three types: fresh, dried and prepared Rehmannia root. In this study, the quality characteristics of prepared rehmannia root were evaluated using four different cultivars that are commonly used in the market. In making prepared rehmannia root, roots of Jihwang 1, Kokang, Togang, and Dagang were dried, soaked in rice wine, and steamed nine times. At each stage, physiochemical properties were analyzed, including yield, which is one of the most important industrial factors to consider. The yield was the highest in Togang at 23.61% and the lowest in Dagang at 21.16%. These yield values showed a highly negative correlation with the moisture content of roots. The fructose and glucose contents were increased during the 3^rd, 4^th and 5^th steaming but then decreased. The sucrose, raffinose, and stachyose content gradually decreased during the first three steaming and were not detected during the 4^th steaming. Additionally, the catalpol content was not detected after the 4^th steaming. On the contrary, the 5-hydroxymethylfurfural content was not detected in the raw root but increased during the steaming. Jihwang1 and Togang exceeded the 0.1% Korean Pharmacopoeia standard after the 5^th steaming, reaching it faster than did the other cultivars. Overall, Togang was the optimal cultivar considering the overall characteristics of its high yield and short steaming time. These results could provide useful information for the industrial use of prepared Rehmannia root based on the requirements and characteristics of each cultivar.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.244-249
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• 1982

In order to reduce malic acid in low-alcohol content appel wine $(6{\sim}9%)$ malate-decomposing yeast, Schzosaccharomyces japonicus var. japonicus St-3 was used. Fallen apples before the harvesting season were collected and extraction was made. The apple extract was fortified with sucrose to make final sugar concentration of 18% in case of 9% base wine. High acid content in the primarily fermented apple wine could be reduced by following with malo-alcoholic fermentation using Schizosaccharomyces japonicus var. japonicus St-3 in second half of alcoholic fermentation using Saccharomyces sp. R-11. Secondary fermentation was proceeded at low temperature $(7{\sim}8^{\circ}C)$ for 130 days using Saccharomyces sp. R-11. Prior to the secondary fermentation, two percent of sugar was added to the base wine in order to produce carbon dioxide gas. And each five percent of specially prepared malt extract and hop extract were added to the base wine in order to increase foam stability. Better shelf-life was observed by keeping high carbon dioxide pressure$(2.3{\sim}2.5kg/cm^2)$ in the bottle. It was assured that the better low-alcohol content apple wine could be brewed by the method which we used above.

• Food Science and Preservation
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• v.17 no.4
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• pp.526-532
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• 2010

Changes in the nutritional components of Daebong-gam (astringent persimmon) fruit were studied during ripening. The pH rose during ripening and total acidity level fell, from pH 5.36 to pH 5.96 and 0.13% to 0.06%, respectively. Total soluble content did not significantly change. Lightness, redness, and yellowness values, as well as ascorbic acid content, decreased during ripening. The levels of moisture, crude protein, and crude fat also decreased, but nitrogen-free content and crude ash level increased. Daebong-gam was rich in K (96.31~239.47 mg/100 g), P (49.10~55.93 mg/100 g), and Na (15.96~18.13 mg/100 g). Fructose and glucose levels were initially high and increased further during ripening. The glucose content was 4.82% in Daebong-gam, 6.73% in Ban-si, and 7.10% Yeon-Si, respectively. Proline, glutamic acid, and aspartic acid were present at high levels in Daebong-gam. The most common fatty acids were palmitic acid and linolenic acid. Succinic acid was the principal organic acid present.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.159-163
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• 2013

As mulberry fruit's functionalities are known to the media, the interest in promoting of consumption and processed products is increasing. But there is no C3G(Cyanidin-3-glucoside) data based on the stability of the pigment during processing. To solve this problems, and to expand the use of mulberry fruit, processing methods was developed for mulberry fruit juice improved cyanidin-3-glucoside(C3G) stability. The results obtained are summarized as follows. The food additive citric acid with 0.3 % improved C3G content and antioxidant ability in the treatment of mulberry fruit and sucrose the ratio of 50 % : 50 %(w/w). In the case of the addition of oligosaccharides, citric acid decreased antioxidant ability. Xylitol treatment showed up the lowest of C3 content, but by the addition of citric acid improved the pigment content and antioxidant activity of the mulberry fruit juice. Addition of citric acid was more affected C3G stability than containers (clear glass bottles, brown glass bottles, aluminum foil, green glass bottle, translucent glass bottles). In the processing of mulberry juice, 3 minutes blanching treatment using microwave dropped C3G content somewhat. Therefore, using this method is not recommended. However in the antioxidant ability, microwave blanching showed a stabilizing effect compared to the other treatments.

• Food Science and Preservation
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• v.17 no.1
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• pp.36-41
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• 2010

Fermentation characteristics of yakju prepared with addition of Opuntia ficus indica were examined, with respect to the nature and concentration of additional added materials. The pH level began to decrease after the secondary brewing stage and the total acid content increased during fermentation. The level of reducing sugars in yakju prepared with Opuntia ficus indica increased at the first brewing stage and then slowly decreased after 4 days of fermentation. The ethanol content of supplemented yakju rapidly increased during the initial 6 days of fermentation, to a maximum content of 17.1% after 14 days. The free sugar content was higher in yakju fermented with Opuntia ficus indica stem compared with fruit. The level of organic acids increased as the amount of Opuntia ficus indica material increased. Organic acid level increased during fermentation and lactic acid was the main organic acid in yakju fermented with Opuntia ficus indica. Sixteen volatile compounds were found by GC-MS in supplemented yakju. The most prominent volatile component was iso-amyl alcohol, followed by butyl alcohol and methyl esters. The DPPH radical-scavenging activity of yakju fermented with Opuntia ficus indica stem was higher than when yakju was prepared with fruit. Sensory scores of yakju fermented with 20% (w/v) fruit and 10% (w/v) stem were greater than those of yakju prepared by other treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1055-1061
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• 2014

Innovative freezing technology is currently applied to preserve foodstuffs for long-term storage. Generally, the quality of frozen food is closely related to the types of freezing and thawing processes. In this study, we characterized the physicochemical properties of onions depending on freezing rate. When onions were frozen at $-40^{\circ}C$, freezing rates were 0.1, 0.5, and $0.7^{\circ}C/min$ depending on air-blast quick freezer mode. Onions were thawed by microwave irradiation at 400 W. Hardness of onion dramatically decreased after freezing and thawing compared with blanched onion. However, the fastest freezing rate did not affect hardness. Thawing loss of onion decreased with a faster freezing rate. For morphological observation, onion frozen at a faster rate showed a smaller ice-crystal size. Vitamin C content decreased upon blanching or freezing, but there was no significant difference according to freezing rate. Although free sugar content also decreased upon blanching and freezing, its highest content was at $0.7^{\circ}C/min$ freezing. Among organic acids, malic acid content was highest at $0.7^{\circ}C/min$ freezing. Based on this study, it could be suggested that a faster freezing rate is effective to improve frozen food quality in accordance with preventing tissue damage or minimizing destruction of nutrients.

• Food Science and Preservation
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• v.23 no.6
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• pp.866-875
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• 2016

In this study, we investigated the variation in free sugars, amino acids, antioxidant activity, and anti-inflammatory activity of Solanum nigrum Linne based on harvest time. Major amino acids identified by HPLC analysis were proline, histidine, and serine. The highest content of total amino acids were found in S. nigrum aerial parts and roots harvested on July 10th and August 10th. Four kinds of free sugars (fructose, glucose, sucrose, maltose) were detected in S. nigrum, and the free sugar content varied significantly with harvest time. The fructose content of S. nigrum decreased with as harvest time increased. The total polyphenol content of S. nigrum was highest in those harvested on August 30th. The antioxidant activity of ethanol extract from S. nigrum collected at different harvest times were measured by DPPH and ABTS radical scavenging assays. The anti-inflammatory activity of these extracts were assayed via nitric oxide suppression in C6 glioma cells with a lipopolysaccharide (LPS)-induced inflammatory response. The anti-inflammatory activity and antioxidant effects were the highest in the extract from S. nigrum collected on August 30th. Good correlations were observed between antioxidant and anti-inflammatory activities in ethanol extract of S. nigrum roots harvested on August 30th.

• Food Science and Preservation
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• v.20 no.2
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• pp.227-233
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• 2013

This study was conducted to investigate the physicochemical characteristic of Carthamus tinctorius L. seed and to assess its total phenol content, total flavonoids content and antimicrobial activity. The moisture, crude protein, crude fat, crude ash and carbohydrates of the Carthamus tinctorius L. seed were 5.58, 37.16, 13.69, 3.52, and 40.05%, respectively. Total amino acid in Carthamus tinctorius L. seed was 391.99 mg%. The major free sugar of Carthamus tinctorius L. seed were fructose(3.29%) and sucrose(1.74%). Linoleic acid(79.46%) was a major fatty acids in the crude fat of Carthamus tinctorius L. seed. The K and Ca contents were the highest in Carthamus tinctorius L. seed. Total phenol and total flavonoids contents of the ethanolic extract were $55.52{\pm}0.99$ mg GAE/g and $78.69{\pm}0.91$ mg QE/g, respectively. The extract from Carthamus tinctorius L. seed showed growth inhibitory effect on Staphylococcus aureus, Salmonella typhimurium, Escheria coli, Candida albicans, Bacillus cereus, Listeria monocytogenes, Vibrio parahaemolyticus, and Clustridium perfringens. These results indicate that the Carthamus tinctorius L. seed extract can inhibit food pathogen associated with total phenol and total flavonoids contents.

• Food Science and Preservation
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• v.24 no.6
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• pp.786-794
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• 2017

This study analyzes the chemical composition and thiobarbituric acid reactive substance levels of Godulbaegi (Youngia sonchifolia M.) depending on collection time. The moisture and crude fat content in leaf and root decreased, while crude fiber, crude protein, carbohydrate, and ash increased with increases in collection time. The mineral elements tended to increase in each sample with increases in collection time. The content of vitamin B increased as collection time increased. Vitamin C content was approximately five times higher in the leaves than that in the roots. Total amino acids in leaf and root increased considerably as collection time increased content of phenolic compounds in root were higher than that in the leaf and these contents increased. Antioxidant activity of Godulbaegi was higher in the root than in the leaf and increased as collection time increased.