• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.634-639
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• 2021

This study investigated the effects of cold plasma (CP) treatment on the properties of biopolymer films prepared with defatted mustard meal (DMM films). CP treatments using N₂, O₂, He, Ar, and dry air did not affect the tensile properties, water vapor permeability, color, and morphology of DMM films, whereas the treatments using He and Ar improved their printability. The tensile strength (TS) of O₂- or air-CP-treated DMM films and the elastic modulus (EM) of O₂-, He-, Ar-, or air-CP-treated films were lower than those of the untreated films. An increase in the power of Ar-CP treatment resulted in an increase in EM. The optimum treatment power and time for minimizing yellowness changes by Ar-CP treatment were 420 W and 40 min, respectively. The results demonstrated the potential application of CP treatment to improve the film properties of DMM films and possibly other agricultural by-product-based biopolymer films, making the films more applicable to food packaging.

• Food Engineering Progress
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• v.22 no.4
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• pp.328-336
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• 2018

The aim of this study was to investigate the effect of pretreatments on quality of frozen peach. Pretreatments including steam blanching, water blanching, high pressure, and osmotic dehydration were applied to two varieties (Daeokgye and Hwangdo). Pretreated peaches were frozen and thawed at $-20^{\circ}C$ and $5^{\circ}C$, respectively. Steam blanching and osmotic dehydration with ascorbic acid reduced ${\Delta}E$ values without change of pH and acidity. Osmotic dehydration with sucrose decreased drip loss and increased brix. Freezing/thawing resulted in an increase of maximum force, while maximum force decreased with increasing time of steam and water blanching. Furthermore, osmotic dehydration with calcium chloride increased maximum force. High pressure decreased maximum force of Daeokgye and increased that of Hwangdo compared with non-treatment. Total polyphenol content, DPPH radical scavenging activity, and ABTS radical scavenging activity were improved by pretreatment including steam blanching, blanching, and osmotic dehydration with ascorbic acid.

• Journal of the Korean Society of Food Culture
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• v.25 no.1
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• pp.100-107
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• 2010

This study was performed to compare the dietary intake and food sources of zinc (Zn), using a database of Zn composition developed in this study, between elementary schoolchildren in a remote rural area (RA, n=58, $9.9{\pm}1.7\;yrs$) and those in an urban area (UA, n=60, $9.4{\pm}1.8\;yrs$) in Chungnam province in Korea. A dietary survey for three days by food record method was performed. All kinds of foods (n=273) consumed by subjects were collected by aliquot sampling method, and the Zn content of these foods were analyzed by wet technique. The results showed that the daily mean intakes of energy, calcium, iron, and vitamin C from diet in the RA were in the range of 49-88% of the Korean DRI (KDRI), while those in the UA were similar to or greater than the KDRI, except for calcium and iron. The daily mean intake of Zn from the RA diet was $7.0{\pm}0.5\;mg/d$ ($114.1{\pm}8.4%$ of the KDRI), and $16.0{\pm}1.0\;mg/d$ ($258.3{\pm}16.3%$ of the KDRI) in that of the UA (p<0.001). The percentage of dietary intake of Zn less than 2/3 of the KDRI was 19.0% in the RA, in comparison to 1.7% in the UA. Those in the RA consumed Zn from plant foods more often than did those in the UA (p<0.001). Beef rib stew was the food source with highest Zn amount for the total subjects, followed by beef rib meat, roasted; and beef soup w/seasoned red pepper sauce. These results showed that some children in the RA had poor Zn nutrition based upon low intakes and poor food sources of Zn, while overall, children in the UA had good Zn nutrition. Therefore, those in RAs should have their Zn nutrition improved through government policy and nutrition education.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.514-520
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• 2008

This study addresses the development of a soy hamburger patty containing enzyme-treated textured soy protein (TSP) as a meat analogue. In order to reduce the beany flavor and enhance the texture, TSP was treated with 0.3% Flavourzyme for 5, 10, 20, or 30 min. The degree of hydrolysis and the water holding capacity of the TSP increased with increasing hydrolysis time. The oil binding capacity of the TSP also increased with increasing hydrolysis time, approaching the maximal value, 175.82%, at 30 min, whereas that of pork scored with the lowest value of 128.67%. The volume of pork was reduced to 81.5% as the result of heat treatment, whereas that of the TSP increased to 140.57%. The values of 'L', 'b', and '${\Delta}E$' differed significantly (p<0.001) with heat treatment, but the 'a' values did not differ significantly. With regard to texture, the hardness values were highest in the pork hamburger patty (PHP), and were lowest in the soy hamburger patty (SHP) containing untreated TSP. The hardness of the SHP containing TSP treated for 20 min did not differ significantly from that of the PHP. The cohesiveness and gumminess of the SHP treated for 20 min were highest, whereas those treated for 10 min were the lowest. The gumminess of the SHP treated for 20 min did not differ significantly from that of pork. The chewiness of the PHP was the highest, whereas that of the SHP treated for 5 min was the lowest. In our sensory evaluation, PHP evidenced the highest scores, followed by the SHP treated for 30 min, as color, texture, beany flavor, and overall quality all improved as the consequence of increasing enzyme treatment duration. In conclusion, it is believed that SHP has great potential as a substitute for meat, in that the flavor, texture, and beany flavor of SHP did not differ significantly from those of PHP.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.56-64
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• 2011

This study was conducted to evaluate the use of exogenous enzymes as a potential means of improving the ruminal digestion (i.e., degradability) of alfalfa hay and rice straw. Twenty six enzyme-additives were examined in terms of protein concentration and enzymic activities on model substrates. The exogenous enzymes contained ranges of endoglucanase, xylanase, ${\beta}$-glucanase, ${\alpha}$-amylase, and protease activities. Six of the enzyme additives were chosen for further investigation. The enzyme additives and a control without enzyme were applied to mature quality alfalfa hay substrate and subsequently incubated in rumen batch cultures. Five of the enzyme additives (CE2, CE13, CE14, CE19, and CE24) increased total gas production (GP) at 48 h of incubation compared to the control (p<0.05). The two additives (CE14 and CE24) having the greatest positive effects on alfalfa hay dry matter, neutral detergent fibre (NDF) and acid detergent fibre (ADF) degradability were further characterized for their ability to enhance degradation of low quality forages. The treatments CE14, CE24, a 50:50 combination of CE14 and CE24 (CE14+24), and control (no enzyme) were applied to mature alfalfa hay and rice straw. For alfalfa hay, application of the two enzyme additives, alone and in combination, increased GP compared to the control at 48 h fermentation (p<0.05), whereas only CE14 and CE14+24 treatments improved GP from rice straw (p<0.05). Rumen fluid volatile fatty acid concentrations throughout the incubation of rice straw were analyzed. Acetate concentration was slightly lower (p<0.05) for CE14${\times}$CE24 compared to the control, although individually, CE14 and CE24 acetate concentrations were not different from the control. Increases (p<0.05) in alfalfa hay NDF degradability measured at 12 and 48 h of incubation occurred only for CE14 (at 12 h) and for CE14+24 (at 12 and 48 h). Similarly, ADF degradability increased (p<0.05) with CE14 and CE14+24. As for rice straw, increased DM degradability was observed at 12 and 48 h of incubation for all enzyme treatments with an exception for CE14 at 12 h. The degradability of NDF was improved by all the enzyme treatments at either incubation time, while ADF degradability was only enhanced at 48 h. Overall, the enzymes led to enhanced digestion of mature alfalfa and there was evidence of improved digestibility of rice straw, an even lower quality forage.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.21-27
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• 2003

This study was carried out to investigate the effect of curing method(tumbling and immersion) and curing time (10 min to 48 hrs) on pH, color, product yield, cooking yield, water holding capacity, shear force, and sensory evaluation of cured pork meat with soy sauce. Curing method had an effective on color of cured meat(before cooking), Meats were tumbled for 30 min, followed by 24 hr and 48 hr delay period showed higher lightness than meat immersed for 24 and 48 hrs, respectively. Tumbling processing improved product yield and cooking yield as compared to immersion counterpart. Therefore, tumbled meat had significantly greater product yield(p <0.05) during working time for 30 min. Increasing curing time improved water holding capacity and tenderness. Although curing time had no influence on sensory evaluation, tumbling processing improved sensory evaluation of texture, juiciness, and overall acceptability fer cured pork meat with soy sauce, as compared to immersion counterpart.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.23-28
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• 2004

The objective of this study was to reduce the tumbling time with improved binding capacity for the manufacture of restructured hams(RHs) using a transglutaminase(TGase). The RHs had 73.9∼75.7% moisture, 3.63∼4.18% fat, 16.6∼20.6% protein with pH values of 5.95∼6.10 and water activity of 0.95∼0.96. No differences in hunter color values or functional properties were observed with the addition of 0.3% TGase or increased tumbling time. However, RHs without TGase had lower(p<0.05) textural profile analysis(TPA) values than those with TGase, regardless of tumbling time. Improved shear values were also observed with increased tumbling time only in RHs without TGase or with the addition of 0.3% TGase as well. This study indicated that 1 hr tumbling with the addition of 0.3% TGase improved the textural characteristics, as compared to the control 1(1 hr tumbling without TGase), resulting in similar shear values of the treatment, which tumbled for 4 hrs without TGase.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.679-683
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• 2006

The effects of dried and fermented guava (Psidium guajava L.) leaf extracts on blood glucose levels were investigated in low-dose streptozotocin(STZ)-induced diabetic mice. Fermented guava leaf extract (500 mg/kg/day) significantly decreased the fasting blood glucose levels after 2-4 weeks of treatment and improved the impaired glucose tolerance in STZ-induced diabetic mice. On the other hand, dried guava leaf extract lowered the blood glucose levels and improved glucose tolerance two weeks after treatment, but exacerbated STZ-induced high blood glucose levels three and four weeks after treatment. Histological and immunohistochemical observation showed that fermented guava leaf extract treatment improved STZ-induced pancreatic beta-cell damage, but dried guava leaf extract did not affect the damage to the beta-cells. These results suggest that fermented guava (Psidium guajava L.) leaf extracts improve the hyperglycemia by protecting the pancreatic beta-cells hom damage in STZ-induced diabetic mice.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.263-273
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• 2020

In this study, in order to confirm the ameliorative effects of onion (Allium cepa L.) flesh and peel on amyloidbeta (Aβ)-induced cognitive dysfunction, we evaluated their in vitro neuroprotection and in vivo cognitive functions. As the result of in vitro neuroprotection, the protective effect of the ethyl acetate fraction of onion flesh (EOF) on Aβ-induced cytotoxicity was similar to that of the ethyl acetate fraction of onion peel (EOP). In the behavioral tests, the EOF and EOP effectively improved the Aβ-induced learning and memory impairments. For this reason, it could be concluded that the EOF and EOP improved the antioxidant activities (superoxide dismutase, oxidized glutathione/total glutathione, and malondialdehyde) in brain tissue. In addition, the EOF and EOP effectively activated mitochondrial functions by protecting the mitochondrial membrane potential, ATP, mitochondria-mediated protein (BAX and cytochrome c), and caspase 3/7 activities. The EOF and EOP also improved the cholinergic system (acetylcholinesterase and acetylcholine). Therefore, we suggest that onion could be used for management of Aβ-induced cognitive dysfunction.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.400-406
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• 2002

In case of doenjang, solution of browning problem might be an important remedy in order to dissolve consumers' dissatisfaction, therefore this study was performed to develop traditional doenjang which has improved in color aspect for consumers' needs. Physicochemical compositions and color values of commercialized traditional doenjang which was processed by history references of our country, were analyzed. doenjang used as samples were processed with traditional meju, which were made with soybean and mixed with various rates after following process such as soaking, steaming, cooling, chopping and grinding. The doenjang processed were storaged at $30^{\circ}C$ for 27 days, and their amino-N, pH, color values and sensory evaluation were analyzed with fermentation period. Furthermore, nitrogen results analyzed were compared with that of commercialized traditional doenjang. In the comparison with control, treated with only traditional meju, and doenjang treatments processed with different mixing rates of traditional meju and steamed soybean, the content of amino-N in control were higher than the others, and the contents of amino-N decreased with increasing contents of steamed soybean. Their pH were changed weak alkalic region into weak acidic region with fermentation period. In the aspect of color, traditional doenjang having the rate of traditional meju and steamed soybean (1:4) was most improved and also, in comparison of result of sensory evaluation with commercial traditional doenjang, its color, taste and falvor were evaluated predominent, therefore it might be thought to have competition on the market.