• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.351-360
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• 2002

The Korean fresh pork loins in vacuum packaged were obtained from three different Korean export companies and investigated for microbiological and sensory properties. The fresh pork loins were stored at 2$^{\circ}C$ for 50 days and analyzed with an interval of 5$\sim$10 days. The results were as follows: The overall numbers of total plate counts and coliform bacteria were higher in swab method than in meat sampling method. The total plate counts in the loins from the company I were maintained low levels ($\prec$10$^5$ cfu/$cm^2$ or $\prec$10$^5$ cfu/g) for entire storage periods(50 days at 2$^{\circ}C$), whereas the loins from the company III had high levels when they were compared to the domestic standard for the allowance limit. The samples from the company III showed that total plate counts were over 106 after about 30 days when determined by meat sampling method and total plate counts were over 106 after 15 days when determined by swab method. The overall numbers of coliform bacteria were also significantly lowest in the samples from the company I, whereas they were highest in the company III. Therefore, all meat companies will have to make an effort to prevent bacterial contamination in each stage such as slaughtering, marketing and consumer in order to ensure the production of safe meat and the extension of shelf-life. For fresh products, scores of intramuscular fat were higher in samples form the companies II and III than those from the company I when visibly evaluated with the standard. There were no significant differences in scores of meat color, drip and fresh meat flavor. However, the samples from the company I had the lowest score of off-flavor and highest score of overall acceptability. For cooked products, there were no significant differences in meat flavor, off-flavor, juiciness and overall acceptability.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.130-137
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• 1986

The five fish meal kojis which contained various ratios of barley were prepared and processed to produce six different fish-soy sauces. The chemical compositions including enzyme activities during fermentation were determined and sensory evaluation was done and changes of absorbance during heating process were also measured. The contents of reducing sugar increased until 12 hours, then slightly decreased and maintained constant level after 36 hours during koji making. The contents of total nitrogen were proportional to the amount of fish meal used in koji. The activities of amylase and protease were increased until 48 hours and then were not changed during koji making. The contents of reducing sugar were increased until 50 days and then were not much changed during koji making. The contents of nitrogen and amino nitrogen in sauces were increased gradually during fermentation. The total acid contents of sauces were increased until 70 days, after which it was constant during fermentation. The absorbances of sauces were increased with time during heating process. In sensory test, the fish-soy sauce the ratio of fish meal: barley of which was 10 : 16 received the highest score for flavor of sauce and the conventional soy sauce, for color and taste in a soup test. Fish-soy sauce resulted good quality when the ratio of fish meal to barley was 10 to 13 and 10 to 16.

• Food Science and Preservation
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• v.10 no.1
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• pp.16-22
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• 2003

This study was conducted to find out effective MA (Modified Atmosphere) gas compositions on the oyster mushroom through statistical analysis of the respiration rate and MA storage for the various packaging materials. Under the various gas compositions, the oxygen consumption rate of oyster mushroom was from 28.9 to 161.4mgO$_2$/kg$.$hr and the carbon dioxide evolution rate was from 53.4 to 166.9 mgCO$_2$/kg$.$hr at 20$^{\circ}C$. The estimated MA condition of oyster mushroom were 2.5∼4.5%O$_2$and 11.5∼l3%CO$_2$by the RSREG(Response Surface Regression). The gas compositions of MA packaging are following that 0.03mm LDPE were 1.6∼3.0%O$_2$and 3.9∼5.3%CO$_2$,0.05mm LDPE were 1.2∼1.3%O$_2$and 9.0∼11.1%CO$_2$and Nylon+PE were 0.9∼1.2%O$_2$and 33.5∼39.6%CO$_2$. The weight loss increased at 0.03mm LDPE but has the lowest value at Nylon+PE. The hardness of pileus and stipe was decreased with storage periods. The $\Delta$E-value increased with storage period and seriously changed in early storage period at 12 and 20$^{\circ}C$. In the 0.05mm LDPE, the gas compositions of packaging were similar to estimated gas compositions from the RSREG and the storage quality was superior to the other packaging materials in weight loss, hardness, and color difference at 4, 12 and 20 $^{\circ}C$.

• Food Science and Preservation
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• v.22 no.4
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• pp.505-511
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• 2015

This study was performed to investigate the effect of drying temperature on the quality characteristics and antioxidant activity of blueberry. Blueberries were dried at different times and temperatures, including A ($40^{\circ}C$, 72 hr), B ($40^{\circ}C$, 48 h and $50^{\circ}C$, 24 hr), C ($50^{\circ}C$, 72 hr), and D ($60^{\circ}C$, 72 hr). The yield and pH ranges of blueberry were determined to be 17.73~31.17% and 3.20~3.25, respectively. The yield rate of A treatments, soluble solid of D treatments, was the highest. The yield rate and soluble content was the highest in the treatment of A and D, respectively. The moisture content and water activity were significantly decreased with the increase in drying temperature (p<0.05). The L value of A treatment, and a and b values of D treatment were the greatest. In the analysis of texture analyzer, hardness, springiness, cohesiveness, gummiess and chewiness were significantly increased with the increase in drying temperature (p<0.05). In the sensory evaluation of blueberry, the appearance and color were the highest in the A treatment. The moisture, texture and taste was highest in the B treatment. The overall acceptability was in the order of B > A > C >D. The total polyphenol content and DPPH radical-scavenging activity were 9.21~13.05 mg/GAEg and 61.90~81.42%, respectively, which were significantly decreased with the increase in drying temperature (p<0.05). Therefore, the optimum time and temperature for blueberry drying was founded to be B treatment ($40^{\circ}C$, 48 hr and $50^{\circ}C$, 24 hr) among other treatments.

• Food Science and Preservation
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• v.16 no.3
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• pp.376-384
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• 2009

Response surface methodology (RSM) was used to monitor the characteristics of ethanol extracts from glasswort (Salicornia herbacea). A central composite design was used to investigate the effects of the independent variables of sample ratio, extraction temperature, and ethanol concentration on the dependent variables color, sugar, salinity, yield, electron donating ability, and total polyphenol content of extracts. The maximum $^{\circ}Brix$ (8.46) was obtained under specific extraction conditions, with a sample ratio of 7.04 g/100 mL, an extraction temperature of $89.01^{\circ}C$, and an ethanol concentration of 34.29% v/v. At a sample ratio, extraction temperature, and ethanol concentration of 7.00 g/100 mL, $89.15^{\circ}C$, and 34.14% v/v, respectively, the salinity was 7.35%. When the sample ratio, extraction temperature, and ethanol concentration were 5.56 g/100 mL, $68.61^{\circ}C$, and 99.14% v/v, respectively, the maximum electron donating ability was 86.10%. A maximized total polyphenol content of 1,140.15 mg/100 g was found with the following conditions: sample ratio of 8.6 g/100 mL, extraction temperature of $64.19^{\circ}C$, and ethanol concentration of 71.74% v/v. Overall, the optimal ranges of extraction conditions for effective components of glasswort were 3.38.5.33 g/100 mL sample ratio, $55.87-76.96^{\circ}C$, and 25.00.67.31% v/v ethanol.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.9-18
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• 2013

The aim of this study is to provide the basic data for yacon [Samallanthus sonchifolius (Poepp. & Endl.) H. Robinson] in dietary food. The nutritional compositons, such as protein, ash, carbohydrate, dietary fiber, vitamin and fructooligosaccharide, were analyzed for 4 yacon germplasm lines. Yacon has low calories with only 46~56 kcal/100 g. The contents of water, fat, ash, protein, carbohydrate and dietary fiber were ranged 85.9~86.8%, 0.1~0.2%, 0.2~0.3%, 0.5~0.7%, 12.2~13.1% and 1.05~1.14%, respectively. The iodine-starch test did not show any color or precipitation reaction, which indicates that yacon has no starch content. However, in the absence of starch, yacon is rich in fluctooligosaccharide, which is between 9.6~11.1%. Maltose is present in the larger amount, followed by sucrose, glucose, and fructose in terms of free sugars. The analysis of minerals revealed that yacon contains potassium in the larger amount of 141~176 mg/100 g F.W., followed by magnesium at 8.2~10.6 mg, calcium, and sodium representing the least present mineral. Yacon proved to have a total of 17 types of amino acids, which are between 404.0~581.8 mg per 100 g of yacon. Glutamic acid, the main sweetening component, is present in the large amount of 94.0~182.2 mg/100 g F.W., followed by aspartic acid, arginine, and alanine. The proportion of the essential amino acid was 24.8~33.6%. Results of analysis also showed that yacon contains 0.001~0.024 mg, 0.03~0.11 mg, 0.02~0.3 mg, 0.3~0.4 mg and 14.1~20.6 mg of ${\beta}$-carotene, thiamin, riboflavin, niacin, and ascorbic acid, respectively. It is also likely to be highly used as functional food material in the future because it is abundant in both fluctooligosaccharide and antioxidants which are important functional components.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.117-125
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• 1981

The changes in chemical compositions of chestnuts were tested during processing in order to elucidate the effects of heat treatments such as boiling, steaming and roasting on the flesh compositions. The results obtained were as follows. 1. The chemical compositions of raw chestnuts were: moisture, 59-61%; total sugar, 24-27%; crude fat, 0.3%; crude fiber, 0.6-0.9%; ash, 1.0%; amino nitrogen, 0.3%; vitamin C, 20-22 mg%; and tannin, 40-48%. 2. The moisture contents were increased to 63.8% by the boiling and to 70.27% by the peeling and boiling from 59.41% of raw ones respectively, whereas decreased to 54.11% by the roasting. 3. Contents of crude protein were decreased to 8.04% by the peeling and boiling procedure from 8.72% of raw ones, and those of amino nitrogen also revealed a decreasing tendency by the heat treatments. However, no significant change was observed in crude fat content. 4. Total sugar contents were decreased by the peeling and boiling procedure approximately 3.0%, whereas reducing sugars were increased 2 to 3 times in the all treatments. 5. Vitamin C contents were decreased 72.0 to 78.0 % by the boiling procedure, 64.2% by the steaming, 51. 6% by the roasting as compared with the raw ones. Tannin contents were increased 11.0% by the boiling, and 46.0% by the roasting respectively, whereas decreased 22.0% by the peeling and boiling procedure. 6. The color was changed to brown with different degree, during the boiling, steaming and roasting procedure. The 0.1% solution of alum appeared to be effective in reducing the browning reaction during the heat treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.598-604
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• 2012

Four types of mixed citrus and carrot juice (CCJ) were prepared with citrus-pressed juice and cake, and carrot-pressed juice. Their physicochemical properties and antioxidative activities were investigated. The four types of juices were created using different ratios of citrus-pressed juice, carrot-pressed juice, citrus-pressed cake, and additives. The mixing ratios of the four CCJ were as follows (all ratios given in the order of citrus-pressed juice : carrot-pressed juice : citrus-pressed cake : additives; 70:30:0:0 for CCJ-1, 65:30:0:5 for CCJ-2, 65:30:5:0 for CCJ-3, and 60:30:10:0 for CCJ-4. Acidity was low in CCJ-3 and -4 at 0.82 and 0.80, respectively, compared with 0.95 in CCJ-1. The fructose, glucose, and sucrose content was 2.11~5.76 g/100 g, 1.20~2.75 g/100 g, and 3.00~4.21 g/100 g, respectively. Total phenolic content was 1.17 and 1.22 times high as 863 and 898 mg% in CCJ-3 and -4, respectively, compared with 735 mg% in CCJ-1. DPPH radical scavenging activities of methanol extracts of CCJ-3 and -4 were 3.05 and 3.29 times as high as 58.7% and 63.3%, respectively, compared with 19.2% in CCJ-1. Superoxide anion scavenging activities were also 1.67 and 1.80 times higher in CCJ-3 and -4 than that of CCJ-1. Inhibition of NO production in methanol extracts of CCJ-4 were 1.15 and 1.57 times as high as 20.9% and 28.5%, respectively, compared with 18.2% in CCJ-1. Based on the sensory evaluation, CCJ-3 was more preferable in terms of color, flavor, taste, and overall preference than CCJ-1, -2, and -4. It was concluded that CCJ-3 made with 65% citrus-pressed juice, 30% carrot-pressed juice, and 5% citrus-pressed cake were high in antioxidative activity and the inhibition of NO production, and more preferable in terms of sensory attributes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.431-440
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• 1987

In order to develop a new type of food source for the effective utilization of fish protein, plastein reaction was applied to improve the functional properties of filefish protein. Plasteins were synthesized from a peptic filefish protein hydrolysate by papain, pepsin, $\alpha-chymotrypsin$ and protease(from Streptomyces griceus) under the optimum conditions of previous paper). Also, L-glutamic acid diethylester and L-leucine ethylester were incorporated into plastein during the plastein reaction by papain. And, General composition, yield, molecular weight, amino acid composition, color and IR spectrum of plasteins were measured. The protein, ash and lipid content of the plasteins were $72\~78\%,\;7.4\~11.8\%\;and\;0.3\~0.9\%$ respectively. The yield of plasteins were papain $55.0\%,\;pepsin\;47.6\%,\;\alpha-chymotrypsin\;38.3\%,\;protease\;23.6\%$, glutamic acid-incorporated plastein (Glu-Plastein) $35.0\%$, and leucine-incorporated plastein (Leu-plastein) $45.7\%$. The glutamic acid and leucine content in Glu-plastein and Leu-plastein were $38.7\%,\;41,7\%$, respectively, while the contents in the peptic filefish protein hydrolysate were $16.01\%\;and\;8.16\%$, respectively. The amino acid compositions were similar to that of the original filefish muscle protein. The major molecular weights of the peptic hydrolysate estimated by gel filteration were 2,000 and 310, and those of plasteihs were 21,000 and 4,900 for papain, 24,000 for pepsin, 18,500 for $\alpha-chymotrypsin$ 6,700 for protease, 24,000 for Glu-plastein and 17,000 for Leu-plastein. The structural changes in freeze-dried filefish meat, the FPC and hydrolysate were not observed on the IR spectrum. But plasteins showed amide I band in $1,600\~l,700cm^{-1}$ range and resulted in a strong band in $800\~850\;cm^{-1},\;700\~750\;cm^{-1}\;and\;650\~700\;cm^{-1}$. The amide I band of Glu-plastein was wider than those of other plasteins and had also a small band at $1,440\;cm^{-1}$.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.264-271
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• 1999

This study was conducted to know the storage stability of Yackwa, a traditional Korean fried cookie, prepared by two different cooking methods; deep fat frying at 160$^{\circ}C$ for 8 min (DFF), and preheating Yackwa dough and then deep fat frying at 180$^{\circ}C$ for 2 min (MW/DFF). Soybean oil (SBO), hydrogenated soybean oil (HSBO) or hydrogenated palm oil (HPO) were used for frying Yackwa. Compared to Yackwa prepared by DFF, all MW/DFF Yackwa samples had low fat content and high moisture content. MW/DFF saved frying time 6 min compared with DFF. Non-hydrogenated soybean oil for frying fats was replaced with hydrogenated types of soybean oil and palm oil to improve the storage stability of Yackwa. To investigate the oxidation stability of Yackwa during the accelerated storage for 15 days at 60$^{\circ}C$, acid value, anisidine value, peroxide value and oxidation value of Yackwas were measured. Acid values of Yackwa made by MW/DFF were higher than those made by DFF through the whole storage periods, regardless of frying fats. Peroxide and anisidine values of Yackwa coated with syrup were much lower than those without syrup. MW/DFF cooking method, using hydrogenated soybean oil or hydrogenated palm oil for frying, showed lowering effects on peroxide value as well as anisidine value, resulting in improved oxidation stability of Yackwa during the storage. In sensory evaluation, the acceptability of MW/DFF Yackwa was higher than those of the commerical products. Yackwa prepared by MW/DFF cooking method using hydrogenated palm oil, showed the highest acceptability in color, taste and texture among the samples.