The antimicrobial activities of Smilax china L. against spoilage bacteria isolated from Mang-gae rice cake were investigated and the storage stability of the Mang-gae rice cake was enhanced. Spoilage bacteria, which cause Mang-gae rice cake to rot, were isolated from commercial Mang-gae rice cake, and most of the isolated strains were identified as Bacillus sp. After the leaves, roots, shoots, and stalks of the Smilax china L. were extracted using 50% ethanol as the solvent, their antimicrobial activities were investigated using the paper disc method by treating them with 50 μL of Bacillus cereus, which is known as a major pathogenic micro-organism in foods that contain starch, as the test organism. The antimicrobial activities of the extracts were compared according to the size of the clear zones around the paper discs. The root extract showed significant antimicrobial activities. When red beans, which are used as stuffing for Mang-gae rice cake, were treated with the root extract of the Smilax china L., the viable cell count of the Mang-gae rice cake was 5.04 Log CFU/g after 48-hr storage, and the cake showed significantly slower growth of bacteria than with commercial products. These results show that treatment of red beans with Smilax china root extract could improve the storage stability of Mang-gae rice cake.
Whole apples were cut with a sharp or dull knife, and whole cabbages and crisp lettuce heads were cut into salad or thin strips with a knife or by hand. The fresh-cut apples, cabbages, and lettuce were packed in low-density polyethylene bags and kept at 4°C, and their qualities were investigated. Browning and softening of the apples that were cut with a sharp knife were more delayed than those of the apples that were cut with a dull knife. The soluble solids and pH of the fresh-cut apples were not affected by the sharpness of the cutting blade. The browning indexes of the fresh-cut cabbages and lettuce were significantly lower in the samples that were cut with a knife than by hand and in the samples that were cut into large pieces. The results suggest that the cutting blade sharpness, cutting tools, and cut types affected the quality of the fresh-cut apples and leafy vegetables, and that the cutting methods which minimized the cutting damage should be used to retard the browning and softening of the produce
The physiochemical property, nutrient composition, and functionality of apple juice sterilized at a low temperature (LT, 70℃, 30 min) or a high temperature (HT, 100℃, 20 min) were analyzed. The pH of the apple juice that was sterilized at LT (pH 4.72) was higher than that of the apple juice that was sterilized at HT (pH 4.57), and the acidity of the apple juice that was sterilized at HT (8.90%) was higher than that of the other sample. The sugar content of the two apple juice samples was 15 °Brix, and the apple juice samples had high potassium, malic acid, and glutamic acid contents. The total polyphenol contents of the apple juice samples that were sterilized at LT and HT were 27.39 mg/100 mL and 23.24 mg/100 mL, respectively. The apple juice that was sterilized at LT had a significantly stronger DPPH radical scavenging activity than the apple juice that was sterilized at HT (p<0.01), and the apple juice that was sterilized at LT had a lower hydroxyl radical scavenging activity level than the other apple juice. Finally, the apple juice that was sterilized at LT showed significantly stronger activities that inhibit enzyme-related oxidation than the apple juice that was sterilized at HT (p<0.05).
The quality characteristics of yenipsambab prepared using various amounts of red, green, and black pigmented rice (0, 10, 20, and 30% added) were investigated. The pH of the cooked rice of yenipsambab decreased significantly as the amounts of pigmented rice increased. The Hunter’s color L value decreased, but the b value increased with increasing amounts of pigmented rice. Moreover, the addition of 10-30% pigmented rice resulted in increased hardness, adhesiveness, cohesiveness, springiness, chewiness, and brittleness compared to the control. Finally, the results of the sensory evaluation and acceptance test showed that the cooked rice containing 10-20% pigmented rice had the highest scores. This study will help in the development of new rice products that are good for the health.
The quality characteristics of kalopanax pictus and Aralica elata shoots during their preservation were investigated according to the salt conditions and storage temperatures to improve the use of the shoots. The results were as follows: the pH of kalopanax pictus shoots duing their storage did not changes with 10% and 12% brine at 4℃ and with 12% brine at 10℃. The pH of Aralica elata shoots is at 4℃ tended to be similar to the kalopanax pictus shoot and decreased at the storage temperature of 10℃. The salinity of the kalopanax pictus and Aralica elata shoots tended to increase during their storage and did not change significantly as their storage temperature changed. The L values of kalopanax pictus and Aralica elata shoots tended to decrease gradually during their storage, and the salt concentrations appeared high. The b value of the kalopanax pictus shoot tended to increase and that of the Aralica elata shoots, to decrease gradually. The a value tended to increase gradually but did not differ with variations in the storage temperatures and salt concentrations. The strength and the hardness of the kalopanax pictus and Aralica elata shoots tended to decreased gradually during their storage and highest in 10% brine at 4℃, and those of Aralica elata shoots were highest in 8-10% brine at 4℃. The Chlorophyll contents of the kalopanax pictus and Aralica elata shoots tended to decrease during their salt storage and did not change significantly as the temperatures and salt concentrations changed. Therefore, it can be concluded that the quality of kalopanax pictus and Aralica elata shoots can be maintained when the are stored in 10% brine at 4℃.
The sensory properties of Kalopanax pictus and Cedrela sinensis shoots were analyzed according to their blanching conditions and the thawing methods used. For the Hunter colors, the K. pictus that was blanched without adding salt for 6 min had the highest L value, and the C. sinensis that was blanched with 1% salt for 6 min had the highest L value. The chlorophyll content of K. pictus was 141.1 mg% when it was blanched for 3 min with 2% salt, and the chlorophyll content of C. sinensis that was blanched without adding salt for 6 min was highest (124.8 mg%). When K. pictus and C. sinensis were blanched without salt addition for 3 min, their texture showed a higher value than that of the other samples. The sensory test result showed the highest overall preference for the sample that was blanched without adding salt for 3 min, among all the samples. The L value of the K. pictus that was thawed in a microwave oven was significantly higher than that of the other samples, but the L value of the C. sinensis that was thawed at 4℃ was higher than that of the other samples. As for the overall preference for the samples according to the thawing method used, K. pictus and C. sinensis scored highest in the case of thawing in a microwave oven.
A new recipe for mandu was developed by adding ripened Korean cabbage kimchi. To counter the bad smell of ripened kimchi and to enhance the function of the food, rosemary was added to it. The preference for the herb over kimchi was determined via a sensory evaluation. The preference was in the following order from highest to lowest: rosemary, lemon balm, and thyme. Ripened Korean cabbage kimchi was added to beef or pork stuffing for mandu. Sensory evaluation was used to determine the optimal contents of ripened Korean cabbage kimchi. The result showed that 75% of the kimchi content was best for beef mandu and 100% for pork mandu.
The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature 40-60℃, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at 50℃ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and 50℃ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.
The effects of soybean powder and chungkukjang powder on the quality characteristics of bread were investigated. The nutritional elements of the soybean powder, chungkukjang powder and wheat flour differed remarkably. The average crude protein, ash, crude lipid, and fiber of soybean powder and chungkukjang powder were approximately 3, 15, 8 and 5 times higher than those of the wheat flour, respectively. The properties of the dough to which soybean powder and chungkukjang powder were added, i.e., its water absorption (%), development time (min) and stability (min) were measured with a farinograph. The water absorption, and development time of the farinogram increased, but its stability decreased when soybean powder and chungkukjang powder were added to white wheat flour. As long as the mixture rate of soybean powder and chungkukjang powder increased, the loaf volume of the bread declined, but the weight significantly increased. The L value decreased, but the a and b values increased in bread crumb that was made from soybean powder and chungkukjang powder. The white wheat flour to which 10% soybean powder and 5% chungkukjang powder were added had the highest scores in flavor, color, texture, taste, and overall acceptability in the sensory evaluation.
The antioxidant substance in black onion was identified. The assays that used 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazo line-6-sulphonic acid) (ABTS+) radicals showed that the ethyl acetate fraction of black onion methanol extract had a higher level of radical-scavenging activity than the other fractions. Two antioxidative compounds were purified and isolated from the ethyl acetate fraction via column chromatographies of silica gel and Sephadex LH-20 using the guided DPPH radical-scavenging assay. The isolated compounds were identified as 3,4-dihydroxybenzoic acid (1) and quercetin (2) based on mass spectrometry and nuclear magnetic resonance. The isolated compounds showed a high level of DPPH and ABTS+ radical-scavenging activity. Compound 2 had a higher level of radical-scavenging activity than 1.
The excellence of pigmented rice with respect to its nutritional composition was proven and the physicochemical properties of five kinds of rice (Jindo black rice, Jindo jeongmi, Boseong black rice, red rice, and green rice) were compared. The crude protein content of black rice harvested in Boseong (10.15%) were higher than that of the other varieties. The crude fat contents of pigmented rice (black, red, and green) were higher than those of polished rice (Jindo-jeongmi and black rice). Boseong black rice had the highest crude fat content. The major free sugar types in the rice varieties were maltose and glucose. The major mineral contents of the unpolished rice (pigmented rice) varieties were as follows: of P, 361.32~570.11 mg%; K, 196.63~210.04 mg%; Mg, 104.11~128.02 mg%; Na, 2.49~8.14 mg%; and Ca, 12.10~16.82 mg%. The major fatty acids in the five kinds of rice were linoleic acid, oleic acid and palmitic acid. The fatty acid contents of the rice varieties did not differ significantly. The black rice (Boseong) had a higher amino acid content than the other varieties. The hunter color values of rice varieties were affected by the colors of tha samples. The L (lightness) value of black rice (Jindo, Boseong) was lower than that of the other samples. The thiamine and riboflavin contents of the red rice (0.48 mg/100 g and 0.14 mg/100 g, respectively) were higher than those of the other varieties (thiamine: 0.36~0.24 mg/100 g and riboflavin: 0.09~0.06 mg/100 g). The hardness of the rice varieties differed significantly (10.75~14.64 ㎏).
The physicochemical properties and nutritional components of fermented black jujube (FBJ) were compared with those of dried jujube (DJ) to improve their utilization as food materials. The moisture contents and brix of the DJ and FBJ were 22.6% and 6.07 brix, and 10.36% and 7.23 brix, respectively. Their L values were 34.78 and 31.82, and the a and b values of DJ were higher than those of FBJ. DJ had a lower water activity level (0.75) than FBJ (0.45), but FBJ had a higher amount of reducing sugar and soluble protein than DJ. The major free sugars in the two types of jujube were fructose and glucose, and their potassium content was highest (about 90%) among minerals. Their unsaturated fatty acid contents were 51.0% and 59.83%, respectively, and the major fatty acids myristoleic acid, palmitic acid, and palmitoleic aid were detected in them.
The changes in the volatile organic compounds in plum after its electron beam irradiation and storage were determined using the simultaneous distillation extraction method and gas chromatograph-mass spectrometry. There were 44, 46, 45, 47, and 38 volatile compounds in the 0-, 0.25-, 0.5-, 0.75-, and 1 kGy irradiated samples, respectively. Also, the volatile flavor components of the plum that was stored for 30 days were identified as 48, 40, 40, 39, and 40 components. The compositions of the volatile compounds of the control and irradiated samples showed a similarity after the storage. Especially, the more important volatile flavor of the plum was identified as hexanal of the C6compounds, (E)-2-hexenal and (Z)-3-hexenal. In particular, hexanal, (E)-2-hexenal, and (Z)-3-hexen-1-ol increased in all the doses, where as hexanol and (E)-2-hexen-1-ol decreased. Among the lactone compounds, γ -hexalactone, γ-octalactone, and γ-decalactone were identified during the storage period in the raw samples. Hexanonic acid and 2-hexenoic acid were not identified during the storage of the samples, and 2-methylprrole was detected only when the storage samples were irradiated at a dose higher than 0.5kGy. Therefore, it was shown that there was no effect on the variation of the volatile organic component suntil 1 kGy in the plum was irradiated with an electron beam.
A total of 17 types of rice flour was collected in the market and investigated with respect to their starch and pasting characteristics. Their water contents, water holding capacities, solubilities, swelling power, amylose contents, damaged starches, particle sizes and pasting characteristics were measured. The water content and water holding capacities of various types of rice flours collected in the market were 7.64-14.97% and 95.22-232.94%, respectively. Their solubilities and swelling power were 1.97-37.40% and 1.33-5.76, respectively. Various types of rice flour had 32.11-305.67 μm particle sizes. Among the various types of rice flour collected in the market, the lowest starch damaged content was 3.17%. The peak viscosities of the samples were 17.74-295.95 RVA. Among the rice flours that were collected in the market, the lowest pasting temperature was 69.72℃. As a result, it was shown that rice flour types with high starch damage contents tend to have higher expressed water holding capacities. Moreover, the samples with lower particle sizes tended to have final viscosities, and pasting temperatures.
The chemical components and anti-oxidant activities of black currant were investigated. The pH, soluble solid and total acidity values were 3.36, 15.11 °Brix, and 1.65%, respectively. The Hunter L, a, and b values were 18.20, 5.13, and 1.08, respectively. The proximate compositions were as follows; moisture, 77.64%; nitrogen free extract, 17.41%; crude fiber, 3.08%; crude protein, 1.28%; crude ash, 0.31%; and crude lipid, 0.28%, respectively. The mineral elements were K (177.36 mg/100 g), P (54.74 mg/100 g), and Ca (26.45 mg/100 g). The free sugar components were glucose (7.71%) and fructose (5.88%). The amino acid contents of the black currant were very rich in glutamic acid (105.73 mg/100 g) and deficient in cystine (5.29 mg/100 g). The ascorbic acid and total phenolic contents were 112.19 mg/100 g and 34.48 mg GAE/g, respectively. The ABTS and DPPH radical scavenging activity levels were 99.48% and 89.03% at the 10 and 1.25 mg/mL concentrations. The reducing power and FRAP of the black currant were dose-dependent. Thus, black currant can be an effective source of functional food substances, i.e., natural anti-oxidants.
Physiological properties of Corni fructus extracts were investigated. The DPPH radical scavenging activity of 90% ethanol extracts had shown 97.20% at 25 mL/g, which was highest in the all extracts. Total polyphenol content of 30% ethanol extracts had shown 140.01mg% at 25 mL/g, which was highest in the all extracts. The polyphenol contents increased as extract concentration rose (25 mL/g>50 mL/g>100 mL/g). Tyrosinase inhibitory effects of all samples were 23.96~88.71%, expecially, the highest at 60% ethanol extracts of 25 mL/g. Nitrite-scavenging abilities under acidic conditions (pH 1.2) were the most effective in all extracts. The results would be useful for understanding of the physiological properties of Corni fructus extracts.
The growth inhibition effect of Doenjang that was prepared with various kinds of solar salt was investigated. Doenjang was prepared using the bacterial koji and five kind of salt with 12% salt concentration (w/w): purified salt Doenjang, one-year aged solar salt Doenjang, four-year aged solar salt Doenjang, topan solar salt Doenjang, and boiled solar salt Doenjang. The Doenjangs were fermented and aged for 18 months. The growth inhibition effects of the water extracts and the methanol extracts of the Doenjangs were measured on AGS human gastric adenocarcinoma cells, HT-29 colon carcinoma cells, and BJ human foreskin normal cells using MTT assay. The water and methanol extracts of the Doenjang samples showed growth inhibition effects on the cancer cells, in the following order of the samples with the strongest to the weakest effect: the four-year aged solar salt Doenjang, the topan solar salt Doenjang, the boiled solar salt Doenjang, the one-year aged solar salt Doenjang, and the purified salt Doenjang. The methanol extracts of the four-year aged solar salt Doenjang (AGS: 55% and HT-29: 48%) showed the strongest growth inhibition effect. In addition, decreased cancer cell numbers and morphological changes in the cancer cells (AGS and HT-29) were observed when the methanol extract of the four-year aged solar salt Doenjang was treated. None of the Doenjang extracts showed a growth inhibition effect on the BJ normal cells, though.
Lycopene, found in tomatoes and tomato products, has antioxidant, anticancer, and anti-inflammatory effects. High-mobility-group box 1 (HMGB1) mediates the pro-inflammatory responses in several inflammatory diseases. In this study, the potential roles of lycopene in the HMGB1-mediated pro-inflammatory gene expressions in the primary human-umbilical-vein endothelial cells (HUVECs) were investigated. The data showed that HMGB1 upregulated the expressions of monocyte chemotactic protein 1 (MCP-1), interleukin-6 (IL-6), secretory phospholipase A2 (sPLA2)-IIA, and prostaglandin E2 (PGE2). Lycopene pre-incubation for 6 h decreased the HMGB1-mediated induction of MCP-1, IL-6, sPLA2-IIA, and PGE2. Further study revealed that the inhibitory effects of lycopene on the HMGB-1 induced expression of pro-inflammatory genes were mediated by the inhibition of two important inflammatory cytokines: tumor necrosis factor (TNF)-α and nuclear factor (NF)-κB. These results suggest that HMGB1 upregulated the expression of pro-inflammatory genes and lycopene inhibited HMGB-1-induced pro-inflammatory genes by inhibiting TNF-α and NF-κB. This finding will serve as an important evidence in the development of a new medicine for the treatment of inflammatory diseases.
The anti-oxidant properties of Lactuca indica were determined using in-vitro assay systems. The vitamin C contents of the leaf and root extracts were 24.14 and 0.38 mg/100 g, respectively. The total polyphenol contents of the leaf and root extracts were 42.8 and 7.66 mg/g, and their flavonoid contents were 23.09 and 0.77 mg/g. The leaf extract showed higher DPPH and ABTS radical scavenging ability than the root extract at all the extract concentrations. Especially, the ABTS radical scavenging ability of the leaf extract was 92.3% at a concentration of 5 mg/mL. The reducing power was increased with the increase in the concentration of extracts, and the leaf extract had a higher reducing power than the root. The Fe2+-chelating ability of the leaf and root were 97.2% and 34.3% at 14 mg/mL, respectively. The IC50 values of the leaf for DPPH, its ABTS radical scavenging ability, and its Fe2+-chelating ability were 0.19, 2.7, and 6.27 mg/mL, respectively, and the leaf extract showed lower IC50 values than root extract. These results show that the L. indica leaf extract contained high amounts of anti-oxidative compounds and had higher anti-oxidant activity levels than the root extract. It is suggested that Lactuca indica is very high in availability as a functional food and in its materials.
The quality of brown rice vinegar that was produced via static culture (A) was compared with the quality of three types of domestic commercial brown rice vinegar (B, C, and D) and of three types of Japanese brown rice vinegar (E, F, and G). The results showed titratable acidity levels of 6.39%, 4.52-6.32%, and 4.51-4.89% in the static-cultured brown rice vinegar, the domestic commercial brown rice vinegars, and the Japanese brown rice vinegars, respectively. The pH levels were 3.28, 2.58-2.97, and 3.03-3.27 in the static-culture brown rice vinegar, the domestic commercial brown rice vinegars, and the Japanese brown rice vinegars, respectively, which show similar values of the static-culture brown rice vinegar and the Japanese brown rice vinegars. The total nitrogen (TN) values of the static-culture brown rice vinegar, the domestic commercial brown rice vinegars, and the Japanese brown rice vinegars were 0.24, 0.03-0.16, and 0.12-0.17, respectively, with the highest value for the static-culture brown rice vinegar, substantial differences among the domestic commercial brown rice vinegars, and similar contents among the Japanese brown rice vinegars. For free sugar, glucose was either detected only in a small quantity or not detected at all in the static-culture brown rice vinegar and the Japanese brown rice vinegars, which showed perfect fermentation. The glucose and maltose contents were higher in the domestic commercial brown rice vinegars. The organic acid content of the static-culture brown rice vinegar was similar to that of the Japanese brown rice vinegars. Therefore, the total acidity content, TN value, sensory property, and quality of the static-culture brown rice vinegar (A) were superior to those of the domestic and Japanese brown rice vinegars.