• Korean Journal of Food Science and Technology
• /
• v.31 no.1
• /
• pp.196-205
• /
• 1999

Kochujang prepared by liquid and solid koji using isolated bacteria(Sunchang 1 and Park 2) showing excellent enzyme activities were gamma irradiated at $15{\pm}1.5\;kGy$ to investigate their qualities from the physicochemical, microbiological and enzymatic points of view during fermentaion at $25^{\circ}C$ for 90 days. The amino type nitrogen contents were $0.6{\sim}0.7%$ after 30 days of fermentation. Irradiation completly stopped gas production which is one of biggest problem of kochujang distribution. Enzyme activities were some different according to koji and irradiation treatment. Amino type nitrogen content as one the most important quality indice was higher in kochujang fermented by isolated bacteria (Park 2) than non inoculated traditional kochujang. But sensory quality was not significantly different.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.7
• /
• pp.1022-1028
• /
• 2016

Milk composition is an imperative aspect which influences the quality of dairy products. The objective of study was to compare the chemical composition, nitrogen fractions and amino acids profile of milk from buffalo, cow, sheep, goat, and camel. Sheep milk was found to be highest in fat ($6.82%{\pm}0.04%$), solid-not-fat ($11.24%{\pm}0.02%$), total solids ($18.05%{\pm}0.05%$), protein ($5.15%{\pm}0.06%$) and casein ($3.87%{\pm}0.04%$) contents followed by buffalo milk. Maximum whey proteins were observed in camel milk ($0.80%{\pm}0.03%$), buffalo ($0.68%{\pm}0.02%$) and sheep ($0.66%{\pm}0.02%$) milk. The non-protein-nitrogen contents varied from 0.33% to 0.62% among different milk species. The highest r-values were recorded for correlations between crude protein and casein in buffalo (r = 0.82), cow (r = 0.88), sheep (r = 0.86) and goat milk (r = 0.98). The caseins and whey proteins were also positively correlated with true proteins in all milk species. A favorable balance of branched-chain amino acids; leucine, isoleucine, and valine were found both in casein and whey proteins. Leucine content was highest in cow ($108{\pm}2.3mg/g$), camel ($96{\pm}2.2mg/g$) and buffalo ($90{\pm}2.4mg/g$) milk caseins. Maximum concentrations of isoleucine, phenylalanine, and histidine were noticed in goat milk caseins. Glutamic acid and proline were dominant among non-essential amino acids. Conclusively, current exploration is important for milk processors to design nutritious and consistent quality end products.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.4
• /
• pp.1243-1252
• /
• 2019

The purpose of this study is to investigate the optimum conditions of biomass pretreatment with potassium hydroxide (KOH) for efficient utilization of cellulose, hemicellulose and lignin from Miscanthus. The optimization of variables was performed by response surface methodology (RSM). The variation ranges of the parameters for the RSM were potassium hydroxide 0.2~0.8 M, reaction temperature 110~190℃ and reaction time 10~90 min. The optimum conditions of alkali pretreatment from Miscanthus were determined as follows: concentration of KOH 0.47 M, reaction temperature 134℃ and reaction time 65 min. At the optimum conditions, the yield of cellulose from the solid fraction after pretreatment was predicted to be 95% by model prediction. Finally, 66.1 ± 1.1% of cellulose were obtained by verification experiment under the optimum conditions. The order contents of solid extraction were hemicellulose 26.4 ± 0.4%, lignin 3.7 ± 0.1% and ash 0.5 ± 0.04%. The yield of ethanol concentration of 96% was obtained using separated saccharification and fermentation.

• Journal of Food Hygiene and Safety
• /
• v.31 no.6
• /
• pp.426-431
• /
• 2016

To compare the quality characteristics of commercial wasabi paste products, the physicochemical and microbial characteristics of 6 samples were analyzed. In addition, the contents of allyl isothiocyanate, which show unique flavor and antimicrobial activity in wasabi paste products, were compared. pH of commercial 6 wasabi products were ranged from $4.12{\pm}0.01$ to $4.90{\pm}0.01$, and titratable acidities of products distributed at cold temperature (CW) were higher $0.60{\pm}0.00{\sim}0.77{\pm}0.02%$ than those of products distributed at room temperature (RW). Salinities of RW were higher ($4.27{\pm}0.06{\sim}7.53{\pm}0.12%$) than those of CW ($2.20{\pm}0.00{\sim}3.60{\pm}0.10%$). Soluble solid and sorbitol contents of RW were higher ($33.00{\pm}1.00{\sim}44.67{\pm}2.08^{\circ}Brix$, $378.90{\pm}63.79{\sim}724.37{\pm}7.85mg%$) than those of CW ($22.00{\pm}1.73{\sim}27.00{\pm}1.00^{\circ}Brix$, $27.67{\pm}9.92{\sim}175.31{\pm}10.56mg%$), respectively. The viable cell counts of samples were $ND{\sim}3.65{\pm}0.23 log\;CFU/g$ without distribution method and packaging type, and yeasts and molds were not detected in 6 wasabi products. Allyl isothiocyanate contents of RW were higher ($53.35{\pm}0.08{\sim}159.76{\pm}0.81mg%$) than those of CW ($24.07{\pm}7.69{\sim}48.19{\pm}0.15mg%$).

• Food Science and Preservation
• /
• v.14 no.6
• /
• pp.617-623
• /
• 2007

To utilize the non-heat treated alcoholic by-products of brown rice(Goami) as food sources, the quality characteristics change according to the treatment conditions of ${\alpha}-amylase$ were evaluated. It resulted that the increase of hydrolysis temperature correspondingly increased the soluble solids, total dietary fiber and total sugar in the by-products of Goami, and the highest reducing sugar content was observed at $80^{\circ}C$. The free amino acids contents were tended to slowly decrease by the hydrolysis temperature more than $70^{\circ}C$, and the highest content of oligosaccharides were detected at the hydrolysis temperature of $80^{\circ}C$. The soluble solid according to the ${\alpha}-amylase$ concentration resulted to increase with the increase of the enzyme concentration and the total dietary fiber revealed similarly showing approximately 0.65%. The high content of reducing sugars was observed at the enzyme concentration around 0.08%(v/w). Total sugars and oligosaccharides contents tend to increase as the concentration of enzyme increased, and the content of oligosaccharides acquired at the enzyme concentration more than 0.10%(v/w) maintained to show rather similar contents. The soluble solids and total dietary fiber by hydrolysis time were found to show 6.66% and 0.65%, respectively at more than 60 min of hydrolysis, and the reducing sugars and total sugars were found to be 3,600 and 4,800 mg% in all treatment groups showing no significant difference. The content of oligosaccharides was increased with the increase of hydrolysis time, and the content was similar at more than 90 min of hydrolysis by ranging around 2,100 mg%. Based upon these results, the by-products of Goami are expected to be used as various food sources showing the highest dietary fiber and oligosaccharides contents by the hydrolysis at $80^{\circ}C$ for 90 min with the addition of 0.10%(v/w) of ${\alpha}-amylase$.

• Korean Journal of Food Science and Technology
• /
• v.34 no.6
• /
• pp.1048-1056
• /
• 2002

Quality of fresh ginger deteriorates rapidly during low temperature storage, and its storage life is short due to sprouting and microbial spoilage. The objectives of this research were to develop, using additives, a minced ginger product, which could maintain acceptable quality for over 30 days, and to investigate its quality changes during the cold storage. Storage stability of minced ginger product was investigated from the standpoint of the inhibition of brown discoloration, gas formation and liquid-solid separation. Fresh ginger was peeled and ground to produce minced ginger (control). Sodium bisulfite, L-cysteine, NaCl, sodium benzoate, modified starch, and/or xanthan gum were added to the control to minimize quality loss during storage, and to develop an optimum formula (A) of minced ginger. Samples were packed in Nylon/PE films, stored at $5^{\circ}C$, sampled at a 30-day interval, and subjected to quality evaluations. Changes in pH, surface color, gas formation, liquid-solid separation, contents of free amino acids, free sugars, organic acids, and fatty acids were determined. Gas formation was effectively inhibited in samples with sodium benzoate and/or NaCl. Samples with xanthan gum did not result in liquid-solid separation. L-Cysteine and sodium bisulfite were effective in controlling discoloration. pH decreased during storage in all samples, except sample A. Organic acid contents of all samples increased during storage, with lactic acid content showing the highest increase. Free amino acid content decreased with increasing storage time. Free sugar content of all samples decreased during storage. Sensory results showed sample A maintained acceptable quality until 90 days of storage. These results suggest that quality of minced ginger could be successfully maintained with the additions of selected additives for up to 90 days.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.1
• /
• pp.59-66
• /
• 2017

This study investigated the quality characteristics and biological activities of rice germ fermented by Bacillus spp. During the milling process, the contents of rice germ in the rice bran (Control) were adjusted to 30% (RG30) and 70% (RG70). The approximate composition, pH, total acidity, total soluble solid, total sugar, polyphenol and flavonoid contents were measured. DPPH radical scavenging activity, xanthine oxidase (XO) and angiotensin converting enzyme (ACE) activities were also determined. We observed that the moisture content decreased after fermentation, while the crude protein was significantly increased. Fermentation remarkably lowered the pH from 5.83~6.26 to 4.77~4.93, thereby elevating the total acidity. Fermentation also increased the total solid contents, from $0.40{\sim}0.87^{\circ}Bx$ to $1.63{\sim}2.20^{\circ}Bx$. The total sugar decreased to 136.81~151.53 mg/mL from 377.56~450.64 mg/mL. Polyphenol contents were the highest in control (0.59 and 0.73 mg/mL before and after fermentation, respectively). Fermentation significantly affected the increase of the polyphenols in both rice germ 30% and 70% samples, from 0.26 and 0.28 mg GAE/g before fermentation, to 0.52 and 0.70 mg GAE/g after fermentation, respectively. There was a slight increase in the flavonoid contents after fermentation. The $IC_{50}$ value of the electron donating ability, as evaluated by the DPPH method, was the lowest in control (3.77 and 3.36 mg/mL before and after fermentation, respectively). Fermentation increased the XO inhibition activity up to 63.69% in control, 49.81% in rice germ 30%, and 59.32% in rice germ 70%. The ACE inhibition activities were also increased in the fermented control, rice germ 30% and 70%, to 40.51%, 22.69% and 33.91%, respectively.

• Food Science and Preservation
• /
• v.25 no.1
• /
• pp.62-70
• /
• 2018

This study investigates, the physicochemical characteristics of Sengmaksan (SM) prepared with Liriope platyphylla (LP) that had been roasted for different times (0, 30, 60, and 90 min, denoted as S-0, S-30, S-60, and S-90, respectively) The Hunter's color values such as lightness (L), redness (a), and yellowness (b) were the highest in S-0, while the lowest was found in S-90. The amount of soluble solid and reducing sugar content of S-60 were higher than the others. None of the samples exhibit significant differences in, their pH and acidity. The total content of phenolic compounds increased with the LP roasting time, but the total flavonoid and total anthocyanin contents of the SM decreased at the same time. The total ginsenoside (Ro, Rb2, Re, Rf, Rg1, Rg2, Rg3, Rh1, and Rh2) content did not show significant differences. The DPPH and ABTS radical scavenging activities increased according to the concentration, as well as with the LP roasting time. The ferric reducing antioxidant power (FRAP) showed trends similar to the radical scavenging activity, but it was more sensitive to the LP roasting time. From these results, the active ingredient in S-60 was higher, and the antioxidant activities of SM increased along with the roasting time of LP.

• Economic and Environmental Geology
• /
• v.27 no.2
• /
• pp.181-190
• /
• 1994

Petrochemical study on the micrographic granite distributed in the Wando area, the southernmost part of the Yeongdong-Kwangju depression is performed to investigate the petrogenesis and differentiation processes of the granitic magma. Polarized light microscopy for modal analyses, electron probe microanalyses of feldspars and biotite, inductively coupled plasma analyses for major and trace element contents were adopted in the study. The lithology of the study area consists of Precambrian metasediments, Mesozoic volcanic and sedimentary rocks, and micrographic granite which intrude into the former. The micrographic granite in the Wando area are distributed in the shape of a cauldron. Modal and nonnative mineral analyses of the micrographic granite fall in the area of granite and granodiorite. The chemical composition indicates that the micrographic granite is I-type and magnetite series. The micrographic granite is characterized by more than 90% of micrographic texture in volume percent. Feldspars in the micrographic granite is alkali feldspars (Or, 45~93) and plagioclases (albite to oligoclase). The biotite has a intermediate composition between phlogopite and annite solid solution. The results of the petrochemical studies indicate that the granitic magma of calc-alkaline source materials reactivated in a compressional environment at the continental margin, and then was differentiated by fractional crystallization. The micrographic granite intruded into a shallow level of the crust (5~7 km) in the late Cretaceous.

• Korean Journal of Community Nutrition
• /
• v.12 no.6
• /
• pp.815-825
• /
• 2007

The study was designed to investigate food waste management practices and to identify factors affecting food waste generation at school food services. A total of 202 dietitians employed at elementary schools participated in the survey. The mean food waste weight per school was 77.54 kg, forty percent of the schools generated food waste of $50{\sim}100kg$ every day and 53% generated plate waste less than 50 kg. Three quarters of the dietitians perceived plate waste as a major component of the food waste and vegetable dishes were a major source of the plate waste. Half of the dietitians used a food waste pick-up service for waste disposal, which was the most preferred waste disposal method. Approximately 90% of the dietitians conducted education on plate waste reduction for students but their perceptions on the effectiveness of the education was inconsistent. The contents were environmental issues (70.3%) and unbalanced food choice (56.7%). According to factor analysis based on performance score, solid waste management practices were grouped into 'information collecting and education', 'supervision of production process', 'cooperation with related groups', and 'control over production planning'. Practices appertaining to 'cooperation with related groups', 'information collecting and education' factor need to be improved. Dietitians should pay attention to 'recycle and reuse of left over' practice. Waste generation differed significantly by dietitians' ages and working experience. In order to reduce plate waste, more effective education materials and methods need to be developed and support from principals, teachers, and parents is necessary.