• Food Science and Preservation
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• v.19 no.1
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• pp.7-11
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• 2012

This study was conducted to determine the effects of the humidity and gas composition on the quality of satsuma mandarins during their heat treatment, in an effort to reduce their acidity. To come up with different humidity and gas conditions, various plastic films were used. The fruits were wrapped with an 18-${\mu}m$ high-density polyethylene (HDPE) punched film, a 30-${\mu}m$ low-density polyethylene (LDPE) film, or a 100-${\mu}m$ LDPE film just before treatment at $30^{\circ}C$ for 55 hours. After heat treatment, the titratible acidity (TA) was significantly reduced while the soluble-solid content (SSC) showed no differences, which resulted in increased SSC/TA ratios in all the treatments. The fruits that were not wrapped with a film, however, which had low RH, developed higher ethanol and acetaldehyde contents than those wrapped with an 18-${\mu}m$ HDPE punched film, which had high RH and a similar gas composition. Among the films, the higher the $CO_2$ concentration in the film was, the more the ethanol and acetaldehyde contents increased, which induced more off-flavor. It was thus concluded that high humidity and normal gas composition are favorable conditions for heat treatment to reduce the acidity of satsuma mandarins.

• Food Science and Preservation
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• v.20 no.5
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• pp.668-683
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• 2013

In this study, we investigated the contents of total polyphenol (TP), total flavonoid, and absorbance at 475 nm ($OD_{475}$) which may produced in solid-fermented leaf of Smilax china L. by Aspergillus oryzae as a new functional components with reddish brown color, contents of water soluble substance (WSS), electron donating ability (EDA), Hunter $L^*$, $a^*$, $b^*$ values, sensory overall acceptability (OA) and also, the inhibitory activities (XOI and AOI) against partial purified xanthine oxidase (XO) and aldehyde oxidase (AO) from rabbit liver which were well known to relate the gout, and alcoholic liver disease, respectively in order to optimize water extraction using response surface methodology (RSM). All the $R^2$ values of the second-order polymonials ranged from 0.85 to 0.98, except for the EDA (0.69) and the XOI (0.78). However, the activities of the EDA and XOI were relatively high in the lower concentration of the fermented Smilax china L. leaf. The effects on the water extraction were highest in the concentration, among the dependent variables, and showed significant differences at the 1% level in the TP, TF and WSS contents and the $a^*$, $b^*$ and $OD_{475}$ values, but the OA showed significant differences at the 5% level. The optimal values of AOI, which was the most important functionality in the Smilax china L. that was predicted via RSM, were 59.48% at the 2.19% concentration, a $90.02^{\circ}C$ extraction temperature and a 4.03 minute extraction time ($R^2$: 0.93, p<0.007). The ranges of all the dependent variables of the optimal water extraction were 1.6~1.8% for the concentration, $83{\sim}93^{\circ}C$ for the temperature and 3.4~4.4 minutes for the extraction time; and the optimal water extraction conditions were a 1.7% concentration, an $88^{\circ}C$ extraction temperature and a 3.9-min extraction time.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.75-81
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• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.

• Applied Biological Chemistry
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• v.43 no.3
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• pp.218-224
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• 2000

The efforts were made to optimite ethanol extraction from persimmon leaf with the time of extraction$(1.5{\sim}2.5\;hrs)$, the temperature of extraction$(70{\sim}90^{\circ}C)$, and the concentration of ethanol$(0{\sim}40%)$ as three primary variables together with several functional characteristics of persimmon leaf as reaction variables. The conditions of extraction was best fitted by using response surface methodology through the center synthesis plan, and the optimal conditions of extraction were established. The contents of soluble solid and soluble tannin went up as the concentration of ethanol went up and the temperature of extraction went down, and the turbidity went down as the concentration of ethanol went down. Electron donation ability was hardly affected by the extraction temperature and had the tendency to go up as the concentration of ethanol went up. The inhibitory activity of xanthine oxidase(XOase) had the tendency to go up as both the concentration of ethanol and the temperature of extraction went up. The inhibitory activity of angiotensin converting enzyme(ACE), the significance of which still was not recognized, showed the maximum when the concentration of ethanol was 27%. In result, the optimal conditions of extraction was the extraction time of two hours, the extraction temperature of $75{\sim}81^{\circ}C$, and the ethanol concentration of $33{\sim}35%$.

• Food Science and Preservation
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• v.30 no.6
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• pp.1012-1028
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• 2023

The findings of this study confirmed the alteration of β-glucosidase activity, nutritional constituents, isoflavones, antioxidant activities, and digestive enzyme inhibition activities in soybeans during solid-state fermentation times with mycelia of Tricholoma matsutake. After nine days, the highest activity level was observed for β-glucosidase (3.90 to 38.89 unit/g) and aglycones (163.03 to 1,074.28 ㎍/g). The sum of isoflavones showed a significant decrease (3,489.41 to 1,325.66 ㎍/g) along with glycosides (2,753.87 to 212.43 ㎍/g) for fermentation, while fatty acids showed a slight increase and amino acids showed a marked increase. Total phenolic and flavonoid contents showed a corresponding increase according to fermentation times (5.58 to 15.09 GAE mg/g; 0.36 to 1.58 RE mg/g). Antioxidant and enzyme inhibition activities also increased; in particular, the highest level of scavenging activities was observed for ABTS (up 60.13 to 82.08%), followed by DPPH (up 63.92% to 71.98%) and hydroxyl (up 36.01 to 52.02%) radicals. Of particular interest, α-glucosidase (6.69 to 83.49%) and pancreatic lipase inhibition (1.22 to 77.43%) showed a marked increase. These results demonstrated that fermentation of soybeans with the mycelia of T. matsutake enhanced the nutritional and functional constituents, and the biological activities of soybeans. Thus, this fermentation technology can be used to produce a novel functional materials from soybeans.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.143-150
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• 1998

In order to evaluate the nitrogen (N) balance, from the different application methods and levels of $^{15}N$ applied to a satsuma mandarin orchard soils in spring, we surface-applied N as urea at the rates of 50 (water-dissolved), 100 (solid and water-dissolved) and 150% (solid) of the recommended rate ($180kg\;ha^{-1}$) in spring (lebeled N), summer (nonlebeled N) with application ratio of 5:2:3. Fruit yield and quality were not significantly affected by any treatment. Nitrogen contents of spring flush leaves in late August were 3.0% regardless of the treatments. The N recovery by parts of tree itself was in the order of leaves, fruits, roots, stems, and the highest recovery per tree was 22.3% in the 50% recommended water-dissolved surface broadcast while there were not much differences for N recovery (11.9 to 13.6%) among the other three treatments. Total N content in top 30cm of soils was 0.47% regardless of the treatments, but N proportion and total residual N from the fertilizer applied increased with increasing N rate while the N recovery in soils decreased. For the recommended N rate, N proportion and the residual N from the fertilizer applied were greater in the water-dissolved surface broadcast than those in soils surface broadcast. The highest total (tree + soils) N recovery was 70.9% in the 50% recommended water-dissolved surface broadcast, but tended to decrease to 52.2, 46.6, and 43.2% for the recommended water-dissolved surface broadcast, 100 and 150% of the recommended solid surface broadcast, respectively.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.209-214
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• 1992

In order to save foreign currency and to domesticize the dairy products, various fresh cheeses and whey drinks were developed and some physicochemical, microbiological and sensory evaluation were performed. The yield of fresh cheese was 22.3%, while that of whey 77.7%. The pH-values of fresh cheeses were $5.90{\sim}6.49$, while those of whey drinks $6.07{\sim}6.49$, and fermented whey drinks $3.97{\sim}4.91$. The acidities of fresh cheeses were $0.09{\sim}0.26%$, while those of whey drinks $0.09{\sim}0.36%$. The contents of solid substances, protein and lactose in fresh cheeses were $25.67{\sim}34.18%$, $7.45{\sim}9.11%$ and $3.61{\sim}4.14%$, while those of whey drinks $7.39{\sim}7.70%$, $0.88{\sim}0.94%$ and $4.93(\sim}6.17%$, respectively. The lactic acid contents of whey drinks varied from $0.01{\sim}0.38%$, where the content in the fermented sample was the highest. The general colony counts of fresh cheeses were $0{\sim}30/g$, while those of whey drinks $0{\sim}80/ml$. The psychrotrophs counts of fresh cheeses were $0{\sim}20/g$, while those of whey drinks $0{\sim}60/ml$. Lactic acid bacterial counts in both products were not detected except for $97{\sim}401{\times}10^8/ml$ in fermented whey drinks. E. coli and fungi were not detected in both products. In sensory evaluation of both products, the strawberry added fresh cheese was the best of fresh cheeses, while the garlic added fresh cheese was the worst. Pure whey drink was the best of whey drinks, while the ginseng added whey drink was the worst.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.219-226
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• 1986

To confirm the application of a newer in vitro assays to determining the nutritional value of marine crustaceans (mainly shrimps and crabs), which have been considered to be highly nutritive depending on their levels of the essential amino acids and digestibility, their C-PERs and DC-PERs were determined and studied the factors influencing their in vitro results. Four species of seawater shrimps and 2 species of seawater crabs were used in this experiment. The in vitro digestibilities showed $83{\sim}86\%$ for raw shrimps and the trypsin indigestibile substrate content (TIS) was ranged from 1.32 to 3.33 mg/g solid expressed quantitatively as mg of purified soybean trypsin inhibitor. The smaller size of shrimps revealed a greater in vitro digestibility and a lower contents of TIS. It was noted that the in vitro digestibility of raw blue crab meat was around $85\%$ while boiled tenner crab meat showed $86\%$ or above, and the leg meat had the greatest in vitro digestibility in the various parts of crab meats. The poor in vitro digestibilities for shrimp's and crab's meat, compared with that of the other seafoods as noted in previous reports, suggest that the drop in pH, due to the change in their freshness during harvesting and frozen storage, resulted in underestimating their digestibilities using four-enzyme digestion technique. The lysine contents in all samples were higher than that of ANRC casein but they contained a slightly lower sulfur-containing amino acids than those in ANRC casein. But the other EAA, such as valine, tyrosine and phenylalanine, were found to be a half as little as that in casein and played a key-factor in calculation of C-PER or DC-PER. It was observed that the value of C-PER and DC-PER for all samples ranged from 2.1 to 2.4, and the predicted digestibilities showed $90\%$ or above in all samples. It was a different results from the fact that the animal proteins bear a higher values and predicted digestibilities than those of C-PER values. The lack of correlation between C-PER and DC-PER values is attributable to the fact that the lower content of valine, tyrosine and phenylalanine, and drop in pH owing to the changes of freshness in marine crustacea proteins. Therefore, if a newer in vitro digestion technique-which are taken into account the pH drop before digestion, TIS content and released free amino acids and/or peptides-developed, C-PER assays can provide more advantages in assessing the protein nutritional value of marine crustacea than any other in vitro assays.

• Journal of Wetlands Research
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• v.9 no.1
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• pp.69-78
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• 2007

Constructed wetlands and other aquatic systems have been successfully used for waste and wastewater treatment in either temperate or tropical regions. To treat waste or wastewater in a sustainable manner, the integrated eco-engineering designs are explained in this paper with 2 case studies: (i) a combination of vertical-flow constructed wetland (CW) with plant irrigation systemfor fecal sludge management and (ii) integrated CW units with landscaping at full-scale application for domestic wastewater treatment. The pilot-scale study of fecal sludge management employed 3 vertical-flow CW units, each with a dimension of $5{\times}5{\times}0.65m$ (width ${\times}$ length ${\times}$ media depth) and planted with cattails (Typha augustifolia). At the solid loading rate of 250 kg total solids (TS)/$m^2.yr$ and a 6-day percolate impoundment, the CW system could achieve chemical oxygen demand (COD), TS and total Kjeldahl nitrogen (TKN) removal efficiencies in the range of 80 - 96%. The accumulated sludge layers of about 80 - 90 cm was found at the CW bed surface after operating the CW units for 7 years, but no clogging problem has been observed. The CW percolate was applied to 16 irrigation Sunflower plant (Helianthus annuus) plots, each with a dimension of $4.5{\times}4.5m$ ($width{\times}length$). In the study, the CW percolate were fed to the treatment plots at the application rate of 7.5 mm/day but the percolate was mixed with tap water at different ratio of 20%, 80% and 100%. Based on a 1-year data of 3-crop plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increasing in CW percolate ratios. The highest plant biomass yield and oil content of 1,000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower is found. In addition to the pilot-scale and field experiments, a case study of the integrated CW systems for wastewater treatment at Phi Phi Island (a Tsunami-hit area), Krabi province, Thailand is illustrated. The $5,200-m^2$ CW systems on Phi Phi Island are not only for treatment of $400m^3/day$ wastewater from hotels, households or other domestic activities, but also incorporating public consultation in the design processes, resulting in introducing the aesthetic landscaping as well as reusing of the treated effluent for irrigating green areas on the Island.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.474-479
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• 2017

Five types of coffee bean, which are usually imported and consumed in Korea, were roasted at $250^{\circ}C$ for 15 min and extracted by using a filter coffee machine. The physicochemical properties, functional components, and radical scavenging activity of coffee bean extracts were investigated. The pH of extract was the highest among the extracts and the soluble solid contents of extracts were $0.9-1.0^{\circ}Bx$. The acidity of the extracts was in the range from 0.46-0.55%, which was not significantly different from the control. Indonesian coffee bean extract showed the highest brown color intensity and contained the highest amounts of caffeine and chlorogenic acid. The highest total polyphenol content was found in Kenyan coffee bean extract. Coffee bean extracts from Indonesia and Kenya showed significantly higher radical scavenging activities than the other extracts. This study showed that coffee bean extracts from Indonesia and Kenya contained a large number of bioactive compounds and high antioxidant activity.