• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.703-707
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• 1995

Shelf-life dating of cooked and heat sterilized food was carried out with the use of principal component analysis (PCA). Changes in color, pH, acidity and sensory properties were measured and analyzed during storage at 20, 30 and $40^{\circ}C$. Acceptability of sample was decreased during storage, shelf-life of sample was determined 1.5, 3 and 3 months at 20, 30 and $40^{\circ}C$, respectively. Application of PCA to quality evaluation, principal component (PC) 1 dominated 49.6% of total variation and PC 2 expressed 28.8%. The rate of change of PC 1 to storage time was 1.3 with increasing temperature of $10^{\circ}C$, and close to shelf-life determined by accepability at 20 and $40^{\circ}C$. Therefore, PCA was applicable to evaluate the quality, predict the shelf-life and investigate the quality parameter of food during storage.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.937-942
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• 2003

Kimchi was prepared with 5, 10 or 20%(w/v) Chinese radish and ripened at $20^{\circ}C$ for 3 days. Acid production and growth of lactic acid bacteria, sensory properties, and several volatile odor components in kimchi were examined. The effects of freeze-drying on the quality of kimchi were also studied. The pH of the control (kimchi prepared without Chinese radish) was 4.31 and gradually decreased as the amount of Chinese radish increased. The acidity of the control was 0.673% and gradually increased as the amount of Chinese radish increased. Viable counts of lactic acid bacteria in the samples did not differ significantly from the control. The pH of freeze-dried/rehydrated kimchi slightly decreased as the amount of Chinese radish increased while its acidity gradually increased. The viable count of lactic acid bacteria of freeze-dried/rehydrated kimchi did not differ significantly as the amount of Chinese radish increased. Overall acceptability and taste of kimchi and freeze-dried/rehydrated kimchi generally improved by the addition of 10% or 20% Chinese radish. Six volatile odor components including ethanol and five sulfur-containing components (SCC) were identified from unripened kimchi, and the level of two SCCs increased as the amount of Chinese radish increased. Eight volatile odor components, ethanol and seven SCCs, were identified from ripened kimchi and the level of five SCCs increased as the amount of Chinese radish increased. Diallyl sulfide and methyl trisulfide were newly detected from the ripened samples, but not from the unripened kimchi. Freeze-drying substantially reduced all of the volatile odor components from kimchi. Five volatile odor components including ethanol and four SCCs were identified from the freeze-dried/dehydrated samples.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.893-897
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• 2003

Prunus mume and Schizandra chinenis H-20 were found to have antibacterial properties against B. subtilis, S. aureus, E. coli KCCM 11591, and P. aeruginosa KCTC 1750. Prunus mume and S. chinenis H-20 showed clear zones of $6{\sim}10\;mm$ for the microbes used, while jujube, Lycii fructus and pine needle showed clear zones of $0.1{\sim}1\;mm$. In the experiment on DNA action, S. chinenis H-20 completely inhibited the growth of B. subtilis, S. aureus, and E. coli KCCM 11591 in the beginning of cultivation and even when added 5 hr after initiating cultivation. Moreover, as the microbes of about $l0^8$ cfu were shown by this test to have strong antibacterial power, they will most likely have an effect in vivo. Prunus mume and S. chinenis H-20 extracts were added to kochujang and fermented at $30^{\circ}C$ for 35 days. Prunus mume kochujang showed a sensory score of 4.29 (somewhat good), suggesting that Prunus mume can he utilized as a functional food ingredient.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.269-276
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• 1983

Experiments were performed to study the rheological and baking properties of bread fortified with various amounts of filefish protein concentrate (FPC). Doughs were prepared from mixtures containing wheat flour and 5,10,15 and 20% of FPC. Standard methods were used to evaluate the rheology of doughs and characteristics of bread. The results were as follows. 1. The water absorption of the fortified doughs increased as FPC increased. FPC caused an increase in development time and stability as measured by Farinograph. 2. In the extensigraph test, FPC yielded a decrease in extensibility and an increase in resistance to extension. 3. Baking tests demonstrated that addition of FPC decreased the volume of loaf and made the crumb darker and coarser. 4. Additional tests were made to examine effect of sodium stearoyl lactylate (SSL) added at 0.25, 0.50, 1.00 and 2.00% on doughs containing 10% headed & gutted FPC. The most appropriate amount of SSL as an additive was 0.5%. 5. In the farinograph, adding 0.5% SSL could delay dough development time and greatly increase stability. 6. When 0.5% SSL was added on doughs containing 5,10,15 and 20% headed & gutted FPC, baking quality was greatly improved. The breads containing up to 10% were acceptable by the addition of SSL, but not in higher level of FPC. 7. The results of sensory evaluations of bread showed that the color, texture and taste of bread containing 5% whole FPC and 5, 10% headed & gutted FPC were reasonably gacceptable.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.262-268
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• 1983

Properties of noodle prepared with FPC and wheat flour were investigated, and the results were summarized as follows: 1. Farinogram showed that the water absorption ratio and dough development time increased as the mixing level of FPC to wheat flour increased. 2. Amylogram showed that the maximum viscosity of the composite flour decreased as the content of FPC increased. 3. In the textural parameters, such as hardness, cohesiveness and gumminess of noodles, there were no marked differences between wheat flour and cooked noodles from the composite flour of 3% or 5% FPC-97% or 95% wheat flour. 4. Regarding weight and volume of the cooked noodles, those of cooked noodles from the composite flour of 3% or 5% FPC-97% or 95% wheat flour were similar to wheat flour alone. As the content of FPC in noodle increased, however, those of cooked noodles slightly decreased, and soup turbidity increased. 5. Results of sensory evaluations showed that the noodle from the composite flour of 3% FPC-97 wheat flour appeared to be the most acceptable, and the noodles from the composite flour of 5% or 7% FPC-95% or 93% wheat flour were judged as acceptable as the wheat flour alone.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.272-277
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• 1990

Some additives were applied to improve Yukwa(Popped rice snack) quality and process modifications were tested for cutting down soaking time and application of rice flour. Addition of soaked soybean (3%, w/w) to dough showed higher expansion rate and better physical properties with more acceptable quality by sensory evaluation of Yukwa. Baking powder, modified starch and alcoholic liquor, Mackeali(rice wine, turbid). Soju(distilled liquor) and Yakju(rice wine, clear), were no positive effect on quality of Yukwa but alcoholic liquor gave more fine texture than others. High temprature soaking $(60^{\circ}C)$ of rice for 3 hours which is near gelatinization temperature of rice starch. gave same quality of Yukwa comparing with long time soaking (12 hours) at room temperature. Extention of high temperature soaking (12 hours) did not improve the quality of Yukwa. The 100 mesh of rice flour by dry milling method was better in expansion rate and hardness than 40 and 80mesh but it was worse than ordinary wet milling. It was notified that milling method and milling mechines for Yukwa preparation should be studied in more detail.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.865-870
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• 1990

Four different fermentation methods of Korean cucumber pickles were compared with conventional method, pickling in 10% NaCl solution at $25^{\circ}C$, in order to improve the storage stability. The methods studied were brining the cucumbers in hot($90^{\circ}C$) 10% NaCl solution(method A), addition of KCl and $CaCl_2$ into the hot salt solution(method B) addition of a sodium salts mixture of phosphates, nitrite and citrate into half fermented pickles prepared by method B(method C), substituted nitrite and citrate with KCl in method C(method D). It was found from results that the method C and D reduced the decreasing rate of pH very significantly by more than 3 fold and method B also showed the reducing effect. However, higher total acidity was measured for method C and D, which was opposite to pH results. Changes in hardness of cucumber showed little difference to control while color of brining solution exhibited some difference in their Hunter values. Organoleptic comparison showed a clear effect of salts mixtures by receiving the significant higher scores in fresh cucumber flavor and lower values in yeast moldy and sour flavor for method C and D when those were compared to control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.179-187
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• 2010

This study examined ways to improve the functional properties of commercial soy sauce using gelatin hydrolysates from the refiner discharge of Alaska pollock, Theragra chalcogramma. The total nitrogen content and pH of gelatin sauce prepared by dissolving the second-step gelatin hydrolysates (15 g), salt (20 g), sugar (5 g), glucose (2.5 g), inosine monophosphate (IMP) (0.5 g), black pepper (0.1 g), caramel powder (0.1 g), ginger powder (0.05 g), garlic powder (0.05 g), vinegar (3 mL), and fructose (3 mL) in water(100 mL) were 1.71% and 5.35, respectively. The results of a sensory evaluation indicated that when preparing blended soy sauce, the optimal blending ratio of gelatin sauce to commercial soy sauce was 20:80 (v/v). Because the total nitrogen content and pH of the blended soy sauce were 1.52% and 5.31, respectively, the blended soy sauce could be sold as a soy sauce. The oxidative property of the blended soy sauce was similar to that of 20 mM ascorbic acid, and its angiotensin-converting enzyme (ACE) -inhibiting activity was 1.5 mg/mL. The results suggest that the antioxidative and ACE-inhibiting activities of commercial soy sauce can be improved by blending gelatin sauce (20) with commercial soy sauce (80). The total amino acid content of the blended soy sauce was 9,107.3 mg/mL, which was higher than that (8,992.4 mg/100 mL) of commercial soy sauce. However, the taste value of the blended soy sauce was 415.8, which was lower than that (431.2) of commercial soy sauce.

• Food Science and Preservation
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• v.13 no.6
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• pp.686-690
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• 2006

Quality properties of legumes (Seoritae and red bean) with soaking of 3% NaCl solution and microwave dying were evaluated. The samples were soaking with 3% NaCl at $25^{\circ}C$ for 6 hr(Seoritae) and 12 hr(red bean). Moisture content of Seoritae and red bean after soaking are 35.8%, and 35.1% respectively. The samples were dried with microwave treatment and cooling with microwave treatment combination secondly to $12{\sim}14%$ for moisture content Hardness of Seoritae was decreased from $12,863g_f$ to $3,309g_f$. There was a difference between varieties on color value. Hardness of cooked rice with ratio of milled rice and legumes(7:3) was $3,165g_f$ which is lower value compared to regular cooked mixed rice. Sensory evaluation of cooked mixed rice showed that treated samples have higher scores on color, flavor, taste, texture and overall acceptability values than those of control.

• Food Science and Preservation
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• v.21 no.1
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• pp.146-150
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• 2014

The feasibility of incorporating jujube powder as a value-added food ingredient in cookies was investigated. The amount of jujube powder added (0~20%) was found to have significantly affected the cookie quality (p<0.05). Furthermore, the pH ranged from 6.16 to 6.69, and moisture content gradually increased from 4.11% to 4.76%, while the spread ratio and loss rate have significantly decreased with the increasing levels of the powder added (p<0.05). Lightness decreased; however, the redness and yellowness, as well as hardness, have significantly increased with the higher amount of jujube powder in the formulation (p<0.05). In addition, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was significantly increased (p<0.05) without remarkable differences between the control and 5% sample, and 15% and 20% sample (p>0.05). The consumer acceptance test indicated that the addition of jujube powder of up to 10% had a favorable effect on the consumer preferences in general. Based on the overall observation, the cookies with 5~10% jujube powder is recommended for taking advantage of the functional properties of jujube powder without sacrificing the sensory quality.