• Korean journal of food and cookery science
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• v.24 no.6
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• pp.811-817
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• 2008

The principal objective of this study was to evaluate the effects of baking method on the quality and shelf-life of Maejakgwa containing nuts and seeds. Four different types of nuts and seeds (almond, cashewnut, coconut, and sunflower seed) were added to flour, and baking method was applied to prepare the Maejakgwa, physicochemical properties of which were then evaluated. The proximate composition analysis demonstrated that crude protein, crude fat, and ash contents were higher in the Maejakgwa containing nuts and seeds than in the control group. The lightness (L) value of the control Maejakgwa was lower than that observed in the groups containing nuts and seeds. Maejakgwa made with cashewnut, coconut, and sunflower seed evidenced higher yellowness (b) values than were recorded in the control and coconut groups. The incorporation of cashewnut, coconut and sunflower seed into the Maejakgwa lowered the hardness values (p<0.05). Our consumer test demonstrated that Maejakgwa prepared with almond was the most highly preferred, and the control group was the least favored. After 30 days of storage at $60^{\circ}C$, the peroxide value of the Maejakgwa containing sunflower seed was substantially higher than in any other groups, thereby suggesting that the addition of sunflower seeds resulted in accelerated lipid oxidation. No noticeable changes in peroxide values were observed in the groups prepared with coconut and cashewnut during storage time. The acid value increased with increasing storage time, and the addition of sunflower seed evidenced the highest values as compared to other groups.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.392-399
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• 2006

In order to develop a new persimmon pickle with a low salt concentration, changes in physicochemical characteristics during soaking of persimmon pickles treated with different organic acids and sugars were investigated at $15^{\circ}C$ for 70 days. The pH of persimmon pickles decreased from pH 6.64 at initial stage to pH 3.99 (control group), pH 2.76-3.33 (citric acid treatment, CT), and pH 3.08-3.34 (acetic acid treatment, AT) after 70-days of soaking. Titratable acidity of AT was higher (0.86-1.18%) than that of CT (0.61-0.78%). After 70-days of soaking, salinity of persimmon pickles treated with stevia leaf powder, sodium saccharin, sucrose, and isomalto-oligosaccharide were 4.94-4.96, 4.00-5.15, 2.99-3.31, and 3.03-3.30%, respectively, and 1.54-3.70% lower than that of the control group (6.69%). The hardness of persimmon pickles in all cases was increased up to 20-40-days of soaking and then decreased. L (lightness), a (redness), and b (yellowness) value of persimmon pickles treated with citric acid were higher than those of AT and the control group. Sensory evaluation of persimmon pickles after 70-days of soaking revealed that CT had the highest scores for color, texture, and overall acceptability. These results indicate that the salt concentration of persimmon pickles could be lowered by the addition of citric acid and various sugars during soaking.

• 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 Food Science and Technology
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• v.34 no.1
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• pp.43-50
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• 2002

To develop commercial semi-solid apple baby food, the physicochemical characteristics of apple puree in relation to different preparing methods and the effect of the addition methods of ascorbic acid on browning reaction were investigated. The preparing methods were classified into 3 groups by initial heating treatment: no heating (A), steaming at $120^{\circ}C$ (B), and blancing at $100^{\circ}C$ (C). The viscosity of tested apple puree was $2,600{\sim}5,856\;cp$, and contents of anhydrogalaturonic acid (AGA) and neutral sugar ranged $4.15{\sim}11.92\;mg%$ and $6.18{\sim}10.65\;mg%$, respectively. Among free sugars tested, level of fructose was the highest $(5.43{\sim}8.87%)$, followed by glucose $(2.11{\sim}4.23%)$, sucrose $(1.64{\sim}2.94%)$, in that order. Since small amounts of ascorbic acid were detected $(1.54{\sim}1.83\;mg%)$, it seemed to be lost by heating process in preparing of apple puree. For apple puree A, its lightness was lower and redness was higher than those of apple puree B and C. Its degree of browning of apple puree was so high that sodium ascorbic acid was added as a antibrowning agent. Puree had low sensory score and nutrient quality. The adding methods of ascorbic acid were classified into 4 groups by adding time: dipping, blending (2), heating (3), and blending + heating (4). Considering color and preference evaluation, preparing method B and adding method 2 showed the highest inhibitory activity on apple puree browning and desirable color for retort baby food. After retort sterilization, the viscosity of apple baby food was decreased from 3,477 cp to 2,294 cp, thiamin was destroyed completely, and the contents of riboflavin and ascorbic acid were decreased 41% and 21%, respectively. However, contents of free sugar and free amino acid and sensory parameter were not influenced by retort sterilization. In overall, the preparing method B-adding method 2 was a good processing condition for the retort apple baby food.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.37-42
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• 2002

This study was performed to provide basic that will predict the usefulness of Gastrodiae Rhizoma as food materials. The physicochemical properties of raw, freeze-dried, and hot air-dried Gastrodiae Rhizoma were investigated and analyzed. The moisture content of raw Gaxtrodiae Rhizoma was 81.20%. The moisture, crude protein, crude fat, crude ash and carbohydrates of freeze-dried Gastrodiae Rhizoma were 7.61%, 6.21%, 1.50%, 2.55%, and 89.74%, respectively. The total dietary fiber (TDF) of freeze-dried Gastrodiae Rhizoma was 11.68%. The K (1265.03 mg%) was the highest mineral found in Gastrodiae Rhizoma. Aspartic acid (1272.10 mg%) and glutamic acid (1249.50 mg%) in Gastrodiae Rhizoma were major amino acids. Linoleic acid (53.79%), palmitic acid (20.17%), oleic acid (11.93%), and linolenic acid (4.78%) were principal fatty acids in crude fat of Gaxtrodiae Rhizoma. Most of the free sugars of freeze-dried Gastrodiae Rhizoma was maltose (11.04%). In color, the freeze-dried showed the highest lightness (94.52) and the $60^{\circ}C$ hot air-dried showed the highest redness(0.76) and yellowness (16.41). The color differences among freeze-dried, $40^{\circ}C$ hot air-dried, and $60^{\circ}C$ hot air-dried Gastrodiae Rhizoma were distinguished markedly. Vitamin C contents in raw, freeze-dried, and $60^{\circ}C$ hot air-dried Gastrodiae Rhizoma were 0.015%, 0.010%, and 0.002%, respectively. The organoleptic characteristics of raw, freeze-dried, and hot air-dried Gastrodiae Rhizoma were evaluated and compared on the basis, 5 points of raw Gastrodiae Rhizoma by 9 points scale. The undesirable characteristics, such as fishy odor, sewage odor, bitter taste, bad and salty taste, decreased, while desirable characteristic such as sweet taste was maintained or increased considerably as drying temperature got higher.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.304-310
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• 2017

The aim of this study was to compare the physicochemical properties of domestic and imported commercial plain wheat flour and dough. Four types of domestic wheat flour (DW; DW1-4) were compared to four types of imported wheat flour (IW; IW1-4). DWs exhibited lower moisture content, lightness (L), and whiteness, and higher protein content, redness (a), and yellowness (b), than those exhibited by IWs. Solvent retention capacity of DWs and IWs was similar; however, DWs showed higher gluten performance index. Pasting properties, analyzed by rapid visco analyzer (RVA), were similar for DW1, DW2, and IWs; however, DW3 and DW4 showed different RVA patterns. Considering that DW3 and DW4 were organic wheat flour, possible incorporation of damaged kernel might increase amylase activities resulting in decreased peak viscosity. Dough resistance (108.4-159.9 g) and extensibility (11.8-16.7 mm) of IWs were higher than those of DWs (78.0-118.7 g, 8.7-12.5 mm, respectively).

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.511-526
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• 2018

Effects of heat treatment on the characteristics of Royal paulownia (Paulownia tometosa) wood were investigated. The results were compared with those of Suwon silver poplar (Populus tementiglandulosa) and Korean red pine (Pinus densiflora) woods. The wood samples of the three species were treated at $160^{\circ}C$, $180^{\circ}C$, $200^{\circ}C$ and $220^{\circ}C$ in an electric furnace for 2 hours. The changes of color, density, mass loss, and relative crystallinity were investigated before and after heat treatment. The lightness ($L^*$) decreased rapidly from $200^{\circ}C$ in all species. There were no change in red-green chromaticity($a^*$) and yellow-blue chromaticity($b^*$) of Royal paulownia and poplar woods with increasing temperature. Whereas, yellow-blue chromaticity($b^*$) of Korean red pine wood decreased sharply from $200^{\circ}C$. Royal paulownia wood showed appreciable color change(${\Delta}E^*$) after heat treatment above $180^{\circ}C$. Poplar and pine woods, however, presented significant color change from $160^{\circ}C$. Color change of the three wood species increased rapidly with increasing temperature. Mass loss of the three wood species by heat treatment was the highest in the Royal paulownia wood and the lowest in the pine wood. Mass loss and relative crystallinity increased and density decreased slightly with increasing temperature. Consequently, it is revealed that Royal paulownia wood showed considerable differences in the temperature of color change, weight loss and change of relative crystallinity compared to the other wood species.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.656-663
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• 2012

Two sorghum(Sorghum bicolor L. Moench cv. Hwanggeumchal-susu and Miryang 3) samples were milled using different milling methods, and their physicochemical properties were tested. Particle size was classified into five groups such as pin mill and low temperature-microparticulation(LTM; 10,000, 20,000, 30,000, and 40,000 rpm). The water absorption index (WAI), water solubility index(WSI), and a rapid Visco analyzer(RVA) were used to examine particle size distribution and color differences. Particle size of sorghum flour prepared using LTM was lower than that prepared using a pin mill. Particle size was further reduced by successive dry milling of the LTM flour. Lightness of colored pigments increased when particle size decreased. The WAI of Miryang 3 pin milling(M1) flour was the lowest after LTM, and WSI was higher in the order of M2, M3, M4, and M5. LTM sorghum flour had significantly higher pasting viscosity, as determined using a rapid Visco analyzer. LTM Miryang 3 sorghum flour(M2~M5) flour showed lower breakdown viscosity and higher final viscosity compared to those of M1 flour, resulting in an increased setback value.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.490-498
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• 2012

The purpose of this study was to evaluate the appearance, sensory and physicochemical characteristics of muffin added glutinous(GSP) and non-glutinous sorghum powder(NGSP). As increasing the amounts of sorghum powder, proximate (moisture, ash and protein) and minerals composition(K, Ca, Mg and Na) of muffin were significant difference. The weight, volume, height, lightness(L-value) and yellowness(b-value) were decreased as increasing the amounts of sorghum powder. In the results of sensory evaluation, appearance, color, flavor, taste, texture and overall quality of untreated muffin were 1.4, 1.6, 1.4, 1.0, 1.1 and 0.9, and muffin added 10% GSP and NGSP were scored relatively high. Antioxidant compounds contents of muffin added sorghum powder were increased as increasing the amounts of sorghum powder. DPPH and ABTS free radical scavenging activities on methanolic extracts of untreated muffin were 0.74 and 1.31 mg TE/g ER, respectively. DPPH and ABTS free radical scavenging activities of 100% GSP muffin were 9.40 and 19.14 mg TE/g ER, and 100% NGSP muffin were 10.59 and 18.78 mg TE/g ER, respectively. The results of this study show that notable antioxidant compounds and antioxidant activity on muffin added sorghum powder are considered to have significant health benefits.

• Korean journal of food and cookery science
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• v.17 no.3
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• pp.195-203
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• 2001

The purpose of study was to improve the storage time of breads with spices. The quality of breads with garlic, ginger and cinnamon powder containing 1 % concentration were investigated using sensory and mechanical evaluation. For 14 days, total microbial count and chemical properties were analyzed at 18$^{\circ}C$. The result of sensory evaluation was not significantly different between control and breads with spices powder. But breads with spices powder were significantly higher than control in texture and acceptability. Especially, bread with cinnamon powder was most favorable in acceptability. The result of total microbial count showed that breads with spices powder were reduced with storing time passed and bread with cinnamon powder was most reduced in breads with spices powder. ks storing time passed, moisture contents and pH range were decreased and L, a and b value were decreased in all breads. Hardness, gumminess and brittleness of torture analysis were increased as storing time passed, but springiness and cohesiveness were decreased. A negative correlation was observed between the sensory and mechanical properties in general. Sensory Properties of springiness and swelling were positively correlated with the acceptability. In the analysis of correlation between the chemical and mechanical properties showed that lightness of mechanical properties had positive correlation with pH range and moisture contents. Moisture contents of chemical properties had negative correlation with hardness, but had positive correlation with cohesiveness of mechanical properties.