• Food Science and Preservation
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• v.14 no.3
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• pp.239-246
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• 2007

The effects of gamma irradiation on the physiochemical and physical characteristics of apples were investigated during post-irradiation storage at $4^{\circ}C\;and\;25^{\circ}C$. The contents of total and reducing sugars were analyzed and the results indicated that apples receiving 1 kGy of gamma irradiation did not show significant differences in sugar contents compared to non-irradiated controls. Important physiological characteristics were evaluated by measurement of total phenolic content and total flavonoid content, reducing power, and radical scavenging ability, and the results indicated that gamma irradiation at a dose of 1 kGy did not affect physiological activities. Changes in physical parameters such as weight loss, strength, cohesiveness and hardness, during post-irradiation storage, were temperature-dependent, whether the apples were irradiated or not The color and sensory acceptance of the apples were not affected by irradiation during cold storage. However, minor deterioration in color quality and sensory acceptance of irradiated apples was noted under ambient temperature storage. We conclude that gamma irradiation(1 kGy) does not affect apple nutritional content stability, functional properties, or physical characteristics, especially upon cold storage after radiation treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.411-416
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• 2002

Yogurt base was prepared from whole milk and skim milk added with 0.2∼1.0% (w/v) of Saururus chinensis(Lour.) Bail water extract (SCe) and fermented with lactic acid bacterias (the mixed strain of Streptococcas themophilus and Lactobacillus bulgaricus) at 37$\^{C}$ for 24 hr. Quality characteristics of the yogurt were evaluated in terms of acid production, number of viable cells, viscosity and sensory property during lactic acid fermentation. The composition of organic acids was also measured by HPLC. Addition of SCe stimulated the growth of lactic acid bacteria and remarkably enhanced the acid production. The viscosity and lactic acid content of yogurt were also increased by addition of SCe. The sensory score of yogurt added with 0.4% of SCe was significantly higher than other groups in taste and overall acceptability The storage abilities of yogurts added with SCe were relatively good at 5$\^{C}$ for 15 days.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.1-8
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• 2000

Six Domestic Wheat Tapdong, Eunpa, Kobun, Olgru, Uri, Kumgang cultivars and one standard wheat Dark Northern Spring (DNS) were milled and determined bread-making properties of dough and bread made the wheats. The ash contents of DNS showed 0.54%, on the other hand, domestic wheat flours showed lower contents than DNS, and Kumgang was the lowest. The Protein contents which suggest the flour gluten content showed 11.68% in DNS cultivars, however 13.85% in Kumgang, 12.35% in Eunpa, 12.32% in Kobun. Valorimeter value in Farinograph data for Kumgang, Kobun, Eunpa cultivars which evaluate the dough formation time and stability showed better result than DNS. Resistance rate in Extensograph for Tapdong and Kobun showed higher rate than DNS. Gelatinization temperature in Amylograph for DNS, Tapdong, Eunpa, Kobun, Kumgang revealed 59$\^{C}$, 59$\^{C}$, 58$\^{C}$, 58$\^{C}$, 59$\^{C}$ respectively, but Uri, Olgru cultivars showed upper temperature which suggest the two cultivars was not suitable for bread making. W(gluten strength) in Alveograph data for DNS showed 297, however, 386 for Tapdong, 327 for Kumgang which indicated that the upper domestic wheat cultivars satisfactory the bread-making properties. In the CO$_2$production of straight bread doughs measured with Meissle fermenter for 5hr, Kumgang cultivar showed the highest CO$_2$ as 333 mg per 30 g of dough. The breads prepared with the above domestic wheat flours showed acceptable quality in sensory test for parameters such as volume, color of crust, symmetry of form, crust, evenness, grain, color, texture, aroma, taste, but the bread made DNS seemed to be superior in organoleptic property to the breads made with domestic wheat flours. The sponge dough bread made with Kumgang cultivars showed the best organoleptic quality among the wheat flours tested. These results indicate that the Kumgang seemed to be practical wheat variety for bread-making.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.873-881
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• 2005

This study was conducted to improve the properties of frozen dough foods (buns and noodles etc.) on the quality deterioration with microwave oven cooking. Microwave is a useful cooking method, but it quickly takes moisture from food surface and makes lowering food quality abruptly. For improvement of these problems, mixing doughs with addition of various additives of 34 types manufactured respectively; starches, modified starches, gums and emulsifiers etc. Each mixing dough produced in sheet type $(30{\times}30{\times}1mm)$ and steamed them, was quickly froze at $-70^{\circ}C$ and packed with polyethylene. Packed samples kept at $-20^{\circ}C$ for 48 hours. After they were steam or microwave treatment packed or non-packed with polyethylene, studied for improvement effects of quality as sensory evaluation and selected 6 type additives; modified starches (TA, ST), gums (AR, GA) and emulsifiers (E, S1) as improvement agent. Because moisture loss from microwave oven cooking leads to quality deterioration of frozen dough foods, additive, such as including starches, modified starch, gums, and emusifiers were added to improve dough properties. Amylogram, scanning electron microscopy, textural analysis, and differential scanning calorimetry revealed addition of additives improved textural properties including surface-hardening of frozen dough foods compared to the control.

• Food Science and Preservation
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• v.10 no.2
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• pp.175-181
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• 2003

Yogurt base was prepared from skim milk supplemented with sweet persimmon powder at the levels of 4% and 7％ and was fermented with Lactobacillus acidophillus. Sweet persimmon powder contained protein 2.2%, fat 30.5%, carbohydrate 56.6% and ash 2.5%, Quality characteristics of prepared yogurt were evaluated for acid production(pH), visible cell numbers, sensory property and oganic acid compositions during fermentation. Lactic acid content in yogurt supplemented with sweet persimmon powder was higher (1.12%∼l.21%) than that (1.05%) in yogurt made with only skim milk after 24 hours fermentation. The sensory score was higher yogurt made with skim milk than yogurt supplemented with sweet persimmon powder in taste, texture and overall acceptability. However, the acid production in yogurt supplemented with sweet persimmon powder were not significantly difference compared to yogurt made with skim milk The antioxidative activity by DPPH(a-a'-diphenyl-${\beta}$-picrylhydratyl) method in yogurt supplemented with sweet persimmon powder and yogurt made with skim milk were higher than BHT 0.005 ％ used as control.

• Food Science and Preservation
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• v.24 no.1
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• pp.84-92
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• 2017

Chicken breast jerky (CJ) was prepared by drying chicken breast at $50^{\circ}C$ for 9 hrs after marinating it in a various sweetening sauce including white sugar (WS), brown sugar (BS), rice syrup (RS), fructooligosaccharide (FO), pineapple concentrate (PC), Rubus coreanus extract (RCE), or honey (H), and its physicochemical and sensory properties were investigated. The CJ was found to contain 22.5-25.0% moisture, 41.0-46.6% protein, and 0.4-1.0% fat, which indicates that it could serve as a high-protein and low-fat snack. The type of sweeteners significantly affected the yield, pH, total viable cell count, and water activity of the CJ, showing ranges of 40.9-50.1%, 5.2-5.9, $2.5-6.2{\times}10^4CFU/g$, and 0.74-0.81, respectively. Both the water activity and pH were the lowest in CJ-RCE where of the highest in CJ-WS. The cohesiveness, springiness, and chewiness of the CJ significantly differed depending on the type of sweeteners (p<0.05). CJ-RCE showed the best taste and overall acceptability in a sensory test. After storage at $50^{\circ}C$ for 2 weeks, thiobarbituric acid reactive substance (TBARS) content (58.3 malondialdehyde (MDA) mg/kg) of CJ-RCE was much lower than those of control beef (75.6 MDA mg/kg) and pork jerky (98.0 MDA mg/kg), showing the good oxidative stability of CJ-RCE. Overall, marination in RCE sauce was suitable for the preparation of CJ with good quality in terms of its water activity, fat and protein contents, sensory property and oxidative stability.

• Journal of Dairy Science and Biotechnology
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• v.19 no.1
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• pp.4-12
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• 2001

The effects of the addition of raw and dried chestnut with levels of 1%($T_1$),2%($T_2$),3%($T_3$) and 4%($T_4$) in skim milk substrate on the volatile flavour compounds and sensory properties of yoghurt fermented with the mixed cultures of YC-380 and ABT-4 during fermentation and storage period were investigated. In all treatments, the contents of acetaldehyde and acetone were detected at 2 hrs. and 1 hr. of fermentation, respectively and decreased with the storage period. The contents of ethanol and diacetyl were detected in all treatments at 3 hrs. and 4 hrs. of fermentation, respectively and increased significantly(p<0.05) with the storage period. The contents of volatile flavour compounds of treatments were increased gradually with decreasing the level of addition of raw and dried chestnut, and increased in order of fermented with YC-380 and ABT-4. The contents of volatile flavour compounds of raw chestnut yoghurt were slightly high compared to those of dried chestnut yoghurt. The taste, flavour and texture of $T_1$ were slightly higher than those of all treatments immediately after fermentation and during the storage period. The scores of sensory evaluation of treatments except $T_1$ were lowered significantly(p<0.05) with increasing the level of addition of raw and dried chestnut. The quality of both of flavour and texture, and taste were superior to chestnut yoghurt fermented with YC-380 and ABT-4, respectively. Generally the scores of sensory evaluation of dried chestnut yoghurt were slightly high compared to those of raw chestnut yoghurt. From the results mentioned above, the addition of raw and dried chestnut at 1%(w/v) level in skim milk substrate were suitable for volatile flavour compounds and sensory property of raw and dried chestnut yoghurt.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.608-613
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• 2007

This study was conducted to evaluate the meat quality of pork produced by feeding fermented rice bran (FRB) (10 to 20%). In the proximate composition analysis there were no significant differences, but the FRB treated groups showed a tendency for higher moisture content and a lower fat content. There were no significant changes found in the physicochemical property analysis, except for cooking loss and water holding capacity, which are the most important factors for estimating meat quality. The cooking loss of the FRB pork was significantly lower than that of the control group (p<0.01). The water holding capacity of the 20% FRB roup was higher than that of the control group (p<0.01). The shear force value of the 20% FRB group was also higher than that of the control group, but the 10% FRB group showed no difference from the control group. The total free amino acid volume of the meat increased, depending on the volume of FRB added. The contents of glutamic acid, glycine, and alanine, which are important factors for taste and flavor, were higher in the FRB groups an the control group. In the sensory analysis, the FRB groups showed high scores for color, aroma, flavor, juiciness, taste, and overall acceptability. Taken together, adding FRB to the feed improved the quality of pork.

• The Korean Journal of Food And Nutrition
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• v.29 no.1
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• pp.65-72
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• 2016

Black tomato (Lycopersicum esculentum) is known to have more ${\beta}-carotene$, lycopene, and vitamin C than general red-colored tomatoes. In this study, we evaluated the quality properties, antioxidant activities and sensory characteristics of black tomato cookies. Cookies were prepared by replacing 0, 1, 3, 5, and 7% of flour with black tomato powder. Density of black tomato cookies tended to be decreased between control (1.20) and 3% added groups (1.12). pH value was decreased from control (6.66) to 7% added group (5.16). Spread factor and loss rate were increased with increasing amounts of black tomato powder. Hardness was gradually increased from $107.77g/cm^2$ in control to $170.50g/cm^2$ in 7% added group. Color measurement indicated that L-value (brightness) was highest in control (70.46) and lowest in 7% added group (45.23); whereas, a-value (redness) increased while b-value (yellowness) tended to decrease with increasing amounts of black tomato powder. Total polyphenol contents and DPPH radical scavenging activities were directly proportional to the amount of black tomato powder. Consumer preference scores in color and flavor of black tomato powder added group were higher than those of control. Characteristic strength test was not significantly different among the groups. Overall, the results indicated that adding 5% black tomato powder is desirable for making black tomato cookies.

• Food Science and Preservation
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• v.21 no.2
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• pp.187-192
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• 2014

This study was conducted to develop a salad dressing using jujube (Zizyphus jujuba Miller) puree and to evaluate the processing and quality characteristics of the salad dressing containing various amounts (0, 10, 20, 30, 40, and 50%) of jujube puree. Jujube puree was prepared by crushing peeled, deseeded and steamed fruit flesh. The dressing ingredients (jujube flesh puree, soy sauce, vinegar, oligosaccharide, olive oil, and water) were mixed, homogenized, and packaged in glass bottles. The quality characteristics (color property, total titratable acidity, soluble solids, viscosity, phenolic compound content, antioxidant activity, and sensory acceptability) of the dressing were analyzed. The lightness ($L^*$) and redness ($a^*$) of the dressing tended to increase as the amount of the jujube puree increased whereas the hue angle ($h^{\circ}$) decreased. The total titratable acidity, soluble solids, viscosity, phenolic compound content, and antioxidant activity of the dressing increased with the addition of more jujube puree. The sensory acceptability (color, smell, taste, texture, and overall acceptability) were significantly higher in the dressing added with 30% added jujube puree than in the other samples. The results show that jujube flesh puree (approximately 30%) can be utilized as an additive for preparing a dressing with simultaneously high antioxidant activity and acceptability.