• Korean Journal of Food Science and Technology
• /
• v.27 no.5
• /
• pp.819-825
• /
• 1995

Two sweet potato CV.(Ipomoea batatas) were examined, i.e. purple flesh sweet potato(PSP) and light yellow flesh sweet potato(LYSP) which varied in degree of sweetness. On a fresh weight basis, nitrogen free extract in cultivars ranged from $25.73{\sim}26.24%$ and PSP contained more crude fat than LYSP. Total amino acids of PSP and LYSP were 5676.57mg% and 4550.86mg%, respectively. Aspartic acid, serine, alanine and valine were the major components in sweet potatoes. Sulfur-containing amino acids are the first limiting amino acid in PSP. The major fatty acids in PSP and LYSP analyzed by GC were palmitic acid, linoleic acid. The content of the saturated fatty acid was less than that of the unsaturated fatty acid. Carbohydrate contents were $75.43{\sim}79.10%$ and neutral sugars contents were $67.22{\sim}64.85%$(dry wt). Two sweet potato CV. contained the most glucose of all neutral sugars. PSP contained 11.88% for uronic acid, 59.42% for starch. Free sugars of PSP(0.82%) was much less than that of LYSP(2.53%). The contents of thiamin, riboflavin and niacin were similar, and the ascorbic acid contents in PSP and LYSP were 63.4mg% and 48.7mg%(dry wt), respectively. Comparing the mineral content in PSP, K was the greatest element in concentration followed by mg, Ca, Na. The total dietary fiber(TDF) value was 13.43% in PSP, 9.79% in LYSP respectively. The ratio of soluble dietary fiber(SDF) content and insoluble dietary fiber(IDF) content to TDF content for PSP were 57.6%, 42.4%, respectively.

• Korean Journal of Food Science and Technology
• /
• v.22 no.7
• /
• pp.724-731
• /
• 1990

The fermentation process of Andong Sickhae including optimal composition of the product was investigated. Through sensory evaluation and ingredient analysis of ten samples prepared in the laboratory and the samples collected from Andong region, we found that the ratio of ingredient of the product by weigh are as follow : [glutinous rice(80) : malt(50) : radish(100) : water(500) : ginger(8) : red pepper(4)]. The level of nitrogen compound turned out to be low while that of soluble protein and salt soluble protein was high. The content of total sugar and reducing sugar was found to be considerable high and among the free sugar, maltose was the highest(80%), followed by glucose and maltotriose. Activities of acid protease and saccharogenic amylase were 1.55 unit per milliliter and $12.5D^{40}_{30}^{\circ}$ respectively. Results of sensory evaluation showed that the good Andong Sickhae turned out to have well harmonized taste of flavor, sweetness and sourness while the color looked slightly red.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.7
• /
• pp.1104-1111
• /
• 2014

To investigate major characteristics affecting the consumer acceptability of Cheonggukjang, the physicochemical characteristics and consumer perception of 16 Cheonggukjang samples (seven commercial samples and nine samples prepared in the laboratory) were analyzed. Overall, consumer acceptability of Cheonggukjang increased with higher contents of amino nitrogen and volatile basic nitrogen, as well as at lower moisture contents. Cheonggukjang samples with higher consumer acceptability showed higher purchase intent (%) and willingness to pay (won/200 gram package), implying consistency in consumer evaluation. Ideal characteristics of Cheonggukjang were lighter color, less water in the soup, stronger characteristic Cheonggukjang taste, sweetness and nutty taste, as well as less off odors, saltiness, and bitterness. The result of this study demonstrates the needs to improve sensory quality by considering the relatively low consumer acceptability of Cheonggukjang samples.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.7
• /
• pp.1075-1080
• /
• 2014

The purpose of this study was to evaluate the physicochemical and sensory characteristics of Sulgidduk substituted with 2%, 4%, 6%, or 8% Shinan Seomcho (spinach, Spinacia oleracea L.) powder (SSP). The moisture content was lowest in the control (38.54%) and increased with greater SSP content, whereas water activity showed the opposite pattern. For color values, lightness significantly decreased with increasing SSP content. For texture analysis, hardness was lowest in Sulgidduk substituted with 4% SSP (154.97 g), and fracturability was lowest at a substitution level of 8%. Adhesiveness was not significantly different among the samples. Springiness significantly increased with greater SSP content. Gumminess and chewiness were highest at a substitution level of 2%. In the sensory evaluation, grass-flavor, bitterness, and off-flavor significantly increased with greater SSP content. Moisture was not significantly different among the samples. Sweetness, color, flavor, softness, and overall acceptability significantly decreased with greater SSP content. However, the overall acceptability scores of all samples substituted with SSP were higher than average. From the results, the optimum level of SSP substitution for production of Sulgidduk is be suggested to be 2~4%.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.6
• /
• pp.792-797
• /
• 2008

The purpose of this study was to investigate the effects of adding various amounts of ingredients on the physicochemical and sensory characteristics of Bokbunja-jelly. The proximate composition of Bokbunja-jelly was 19.0% for the moisture and 0.8% for the crude protein. The Hunter L-values of Bokbunja-jelly prepared by adding 10 g RME or 120 g sucrose were higher than that of Bokbunja-jelly prepared by adding 20 g RME or 100 g sucrose. The Hunter b-values of Bokbunja-jelly prepared by adding 20 g RME or 120 g sucrose was higher than that of Bokbunja-jelly prepared by adding 10 g RME or 120 g sucrose. The hardness and chewiness were increased with decreasing Rubus coreanus Miquel extracts. According to the results of the sensory evaluation, no significant differences in flavor, sweetness, hardness, elasticity and overall qualities were found. According to the results of physicochemical properties and sensory evaluation, the optimal recipe for preparation of Bokbunja-jelly was determined to be 240 g water, 120 g sugar, 110 g glucose syrup, 4 g agar, 20 g Rubus coreanus Miquel extracts and 0.3 g Rubus coreanus Miquel flavor.

• Culinary science and hospitality research
• /
• v.18 no.4
• /
• pp.255-265
• /
• 2012

This study aimed to determine the physicochemical and sensory qualities for yogurt dressing prepared with blueberry juice(0, 10, 15, 20, and 25%). As the amount of added blueberry juice increased, citric acid, malic acid and succinic acid contents increased, but tartaric acid, lactic acid and acetic acid contents decreased. The pH of control group(3.75) was higher than that of the others(3.68-3.48). Sweetness of yogurt dressings decreased as the amount of added blueberry juice increased. DPPH radical scavenging activity of the control group was 26.44%, whereas those of yogurt dressings with blueberry juice ranged from 63.16-87.46%. Color L and b values decreased significantly, whereas a value increased significantly by addition of blueberry juice. Viscosity of the control group was lower than those of the others. The sensory property results showed that yogurt dressing with 20% blueberry juice was rated best. It was also preferred most. These results suggest 20% of blueberry juice is the best substitution ratio for yogurt dressing.

• Journal of the East Asian Society of Dietary Life
• /
• v.24 no.6
• /
• pp.793-801
• /
• 2014

This study evaluated the qualitative properties of lotus root (Nelumbo nucifera) peels as food materials. Proximate composition, sweetness, pH, total acidity, color, mineral, fatty acid, free sugar and organic acid contents of preprocessed lotus root were measured. Crude moisture, protein, and total fiber contents of non-peeled treated Lotus roots were higher than those of peeled treated lotus roots (p<0.05). Lightness and yellowness of color were reduced by peeling process, whereas redness increased (p<0.05). The mineral contents of Mg, Ca, Fe and Na were higher in non-peeled lotus roots, whereas peeled treated lotus root showed higher K contents (p<0.05). The major fatty acids were palmitic, oleic, linoleic and linolenic acids. The total free sugar content of non-peeled lotus roots was higher than that of peeled treated lotus roots (p<0.05). Glucose content was not significantly different, whereas fructose, sucrose, and maltose contents were significantly different. The organic acid and free amino acid contents were higher in peeled lotus roots (p<0.01).

• Journal of Ginseng Research
• /
• v.33 no.4
• /
• pp.343-348
• /
• 2009

This study was conducted to produce a new red ginseng by steaming ginseng using a new pre-treatment method, so as to develop ginseng products with improved flavor and thereby expand ginseng's consumer base. The color parameters (Hunter value), free sugar contents, and ginsenoside contents of the powder from the dried red ginseng, and the sensory test of the semi-dried red ginseng and the decoction from the dried red ginseng, were measured to investigate the effect of acid (ascorbic acid or citric acid) impregnation pre-treatment on red ginseng. The powder from the acid-pretreated red ginseng became lighter and more yellow than the red ginseng that was not pre-treated, but the redness (avalue) of the powder from the acid-pre-treated red ginseng increased. The ginsenoside contents of $Rg_2+Rh_1$ and $Rg_3$ increased with the acid treatment. There was a significant difference in the color and sweetness of the semi-dried acidtreated and non-treated red ginsengs in the sensory test. As the results of the sensory test were expressed in the hedonic scale, however, there were significant differences in the degrees of bitterness, astringency, sourness, odor, and color of the red ginseng decollation. Especially, the acid-treated red ginseng extract tasted less bitter, which shows the potential of new red ginseng products with improved ginseng flavor.

• Journal of Life Science
• /
• v.20 no.3
• /
• pp.462-465
• /
• 2010

Sweetness plays an important role in providing calories and promoting appetite for food. Since it has been known that genetic factor(s) is involved in individual differences in taste sensitivity in humans, this study aimed to examine genetic variations of the TAS1R2 gene, one of the components for tasting sweet compounds, by using DNA sequencing analysis from 98 unrelated Korean subjects. As a result, 12 different single nucleotide polymorphisms (SNPs) were identified in the hTAS1R2 gene and most of them were nonsynonymous. Also, two novel SNPs were found for the first time in this study. It was noted that the frequencies of these SNPs were common in the Korean population. 20 different haplotypes with coding SNPs (cSNPs) were also found in this study. Three out of these haplotypes were common, showing frequencies of > 10%. The repertoire and frequencies of cSNPs and haplotypes in the hTAS1R2 gene will provide information that will help identify a functional ligand receptor common in the Korean population.

• Korean journal of food and cookery science
• /
• v.33 no.2
• /
• pp.127-136
• /
• 2017

Purpose: This study examined the effect of different gluten-free flours on the properties of cookies. Methods: Each gluten-free cookie was made from wheat, brown rice, buckwheat, corn, sorghum, teff, or black rice. Results: Baking loss was highest on sorghum (18.85%) and the lowest on teff (12.73%). The spread factor was highest on brown rice (8.20) and lowest on corn (7.60). The density was similar in all samples (1 g/mL). pH was the highest on buckwheat (6.45) and lowest on wheat (5.96). While L-value, a-value and b-value were lowest on black rice, the ${\Delta}E-value$ was the highest on black rice (35.57). The hardness was highest on wheat (30.28 N) and lowest on teff (14.87 N). The polyphenol and flavonoid content was the highest on buckwheat ($25.97{\mu}g\;GAE/mg$) and the flavonoid content was the highest on black rice ($24.33{\mu}g\;QE/mg$). The DPPH IC50 value was highest on wheat ($352.41{\mu}g/mL$) and lowest on black rice ($33.59{\mu}g/mL$). The ABTS $IC_{50}$ value was highest on wheat ($349.30{\mu}g/mL$) and lowest on black rice ($57.72{\mu}g/mL$). The results of the sensory properties revealed color to be highest on corn (7.33). The top grain was similar in all the samples (5.43-6.57). Flavor was highest on black rice and teff (6.43-6.48). The softness was the highest on wheat, sorghum, teff, and black rice (6.48-7.05). Sweetness was highest on sorghum, teff, and black rice (6.19-6.71). The overall preference also was highest on sorghum, teff, and black rice (6.14-6.48). Conclusion: Gluten-free flours can improve the quality characteristics and antioxidant activities of cookies.