• Food Science and Biotechnology
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• v.14 no.3
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• pp.392-398
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• 2005

Fresh, and sun- and oven-dried red peppers were analyzed for volatile components. Also, their odor-active compounds were determined using gas chromatography-olfactometry (GC-O). More diverse volatile components, such as aldehydes, ketones, acids, and esters, were found in dried samples than in fresh ones. They included hexanal, ethyl acetate, ${\alpha}$-ionone, and ${\beta}$-ionone. Some Strecker aldehydes, 2-methyl butanal and 3-methyl butanal, were found only in dried red peppers. More hydrocarbons of high volatility and terpene-type components, such as ${\gamma}$-terpinene and aromadendrene, were detected only in fresh red peppers. A considerable amount of naphthalene was formed during sun-drying, whereas 2-furancarboxaldehyde, 1-methyl-1H-pyrrole and benzeneethanol were detected only in oven-dried red peppers. Characteristic odor of fresh ones could be attributed to 3-penten-2-o1, 2-methyl-2-butenal, 2-methoxy phenol, 2-hydroxy-methyl-benzoate, and 2-phenoxy ethanol, whereas some odorants, including 2-pentyl furan, naphthalene, hexyl hexanoate, and ${\alpha}$-ionone, could be responsible for distinctive odor property of sun-dried red peppers. 2-Furancarboxaldehyde, benzeneethanol, 4-vinyl-2-methoxy phenol, and unknown played important roles in odor property of oven-dried red peppers.

• Food Science and Industry
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• v.50 no.2
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• pp.12-26
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• 2017

Processing steps such as washing and cutting, involved in preparing fresh-cut produce causes tissue damage, leading to rapid quality deterioration. Major defects of fresh-cut produce are discoloration, softening, off-odor development, and microbial growth. Packaging of fresh-cut produce has been changed to reduce these quality problems. Flexible packaging film is widely used to pack fresh-cut produce. Vacuum packaging was the popular packaging method in the beginning of fresh-cut industry in Korea. Vacuum packaging creates high $CO_2$ and low $O_2$ levels to control browning of fresh-cut produce. However, these conditions induce some visual defects and off-odor development. Discoloration problem was also found when fresh-cut produce was packaged with conventional packaging film or plastic tray. Modified atmosphere (MA) packaging is effective for prolonging shelf-life of fresh-cut produce by decreasing $O_2$ and increasing $CO_2$ concentration in the package. Retail MA packaging using different oxygen transmission rate (OTR) film and micro-perforated film has started to be applied to fresh-cut produce in Korea. Proper MA package design that provides optimum range of $O_2$ and $CO_2$ partial pressures is one of the major challenges in the industry. An initial package flushing with $N_2$ or an low $O_2$/high $CO_2$ atmosphere is also used to more rapidly establish steady-state MA condition. Film OTR and $O_2$ flushing affects the fermentative volatile production, off-odor development, electrolyte leakage, discoloration, $CO_2$ injury, microbial population of fresh-cut produce. There is also a demand for convenient packaging to attract consumers. Rigid fresh-cut produce container for retail market has increased since the packaging provides excellent protection from physical damage during transport. Rigid tray used as actual serving vessel for the consumer is increasing in Korea. The tray with flexible lid to wrap or seal fresh-cut produce is more and more gaining popularity. Further practical technology to control quality change and microbial growth for each fresh-cut product has been studied since various fresh-cut items were required. The fresh-cut industry also focuses on searching for more convenient and environmentally friendly packaging.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.891-898
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• 2008

The physicochemical and sensory characteristics of commercial film-packed soybean sprouts from domestic cultivars were investigated. The hardness of the cotyledons was higher than that of the hypocotyls in fresh and cooked soybean sprouts (Kongnamulmuchim). Furthermore, the color determination showed that the hypocotyls and cotyledons of the soybean sprouts had a light green color that was not eliminated by cooking. The acceptability of fresh soybean sprouts was negatively correlated with a beany odor, beany taste, and grassy taste, but positively correlated with a nutty odor, nutty taste, and sweet taste. In addition, the acceptability of boiled soybean sprouts was negatively correlated with a beany and grassy taste, and positively correlated with a nutty odor and taste. Furthermore, the acceptability of cooked soybean sprouts was negatively correlated with a beany odor, beany taste, grassy odor, and grassy taste, while it was positively correlated with a nutty odor and taste. Finally, the lipoxygenase activity of the cotyledons was higher than that of the hypocotyls in fresh and boiled soybean sprouts.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.450-455
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• 2005

This study was conducted to determine firstly the composition of the essential oil from fresh changpo (Acorus calamus var. angustatus Bess) roots quantitatively and qualitatively by use of two internal standards, and secondly volatile compounds which are primarily responsible for the aroma of changpo roots. Simultaneous steam distillation and extraction method was used for essential oil extraction, and aroma extract dilution analysis (AEDA) and sniffing test by gas chromatography/olfactometry (GC/O) were used to detect the characteristic impact odorants. According to the instrumental analysis of changpo root essential oil, cis, trans-famesol (47.56 mg/kg of fresh wt), octanoic acid (23.73 mg/kg of fresh wt), trans-2-dodecenal (20.28 mg/kg of fresh wt) and trans, trans-farnesol (13.81 mg/kg of fresh wt) were the most abundant compounds. Geranyl acetate, trans-nerolidol and trans, trans-farnesyl acetate were evaluated as the characteristic impact odorants of changpo roots from results of AEDA and sniffing test. Especially, geranyl acetate was considered as the most similar odor component to changpo roots by organoleptic evaluation with GC/O.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.717-723
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• 2006

Chemical characteristics of soybean oil after deep-frying with potato sticks (200 g, 10% w/w of soybean oil) were studied according to the 34 deep-frying times. After consecutive 34 deep-frying, total polyunsaturated FA contents was gradually decreased while the total saturated FA and trans FA were increased. Acid value and peroxide value were increased while iodine value decreased, respectively. The Hunter $L^{\ast}$ value decreased while each $a^{\ast}\;and \;b^{\ast}b$ value were gradually increased. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of frying oils against the times of deep-trying. The proportions of 1st and 2nd principal component analysis showed 75.97% and 21.23%, respectively. While 6 among total 12 sensors well responded to discrimination of odor in the repented frying oils, suggesting that the odor pattern of each oil after deep-frying would be discriminated against fresh soybean oil, especially after 14 times. From the results, electronic nose could differentiate the degree of quality deterioration of the repeated deep-frying oils.

• Korean Journal of Human Ecology
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• v.9 no.4
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• pp.505-512
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• 2000

The fresh ginseng was packed individually with a soft film bag, ONY/LDPE/L-LDPE (20$\times$30 cm, 93 ${\mu}m$) and stored at $25^{\circ}C$ for twenty days. The Quality-related appearance parameters and the sensory characteristics of the fresh ginseng were evaluated. The quality of the fresh ginseng was lowered mainly due to hardness decrease with increasing storage time, while the occurrence of mould was rarely observed. The normal ginseng had strong fresh ginseng odor and strong bitter taste and its hardness was well maintained during twenty days. The softened ginseng had pungent and sour odor, sweet and sour taste and sticky texture.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.139.1-139
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• 2003

검은비늘버섯(Pholiota adipose)의 향기성분을 조사하기 위해 생버섯을 SDE로 추출하여 농축한 후 GC/MS로 정성하였으며 향기특성은 GC/olfactometry를 이용하여 확인하였다. GC/MS로 정성된 화합물은총 52종이었으며 함량이 높은 화합물로는 hexanal (8.55%), n-heptadehyde(13.02%), 2-pentyl furan(4.82%), benzeneacetaldehyde (3.34％), (E,Z) -2,4-Decadienal(3.06％), 6,10-dimethyl 5,9-undecadien-2-one(11.75％) 이었으며 1-octen-3-ol, 3-octanone, 3-octanol, 2-octanol, 1-octanol 등의 C8화합물이 검출되었다. Sniffing test 결과 주요한 향기특성으로는 burnt odor(843, +++), fresh fruity odor(1-hexanol ++), fresh mushroom(n-heptaldehyde, +++), mushroom like(1023, +++), refreshing sweet(benzeneacetaldehyde, +) 등으로 나타났다.

• Asian Journal of Atmospheric Environment
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• v.2 no.2
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• pp.109-115
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• 2008

In this study, the emissions of carbonyl compounds as offensive odorants were measured using three food types (Kimchi, fresh fish, and salted fish) as a function of time. Odor samples for each food type, collected at 0, 1, 3, 7, and 14 days, were analyzed by high performance liquid chromatography (HPLC). Only three kinds of carbonyl compounds were quantified above their respective detection limits: formaldehyde, acetaldehyde, and acetone. The emission patterns of these compounds were distinguishable from each other. Formaldehyde tends to peak at the beginning and decrease through time with unique patterns. Conversely, acetaldehyde and acetone seem to increase gradually through time. The results showed that relative patterns of carbonyl emissions were more distinguishable by compound type rather than food type.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.322-328
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• 2010

This study was conducted to examine the sensory attributes, gingerol content and volatile components of ginger paste resulting from microbial fermentation. In the ginger samples, a total of eighteen attributes were determined to characterize the sensory attributes from descriptive analysis. These eighteen attributes consisted of the following: one appearance, eight odor/aroma, eight taste, and one aftertaste attribute. The ginger fermented using Lactobacillus plantarum produced a ginger aroma and putrid taste, whereas the sample fermented with Lactobacillus brevis showed a decreased ginger aroma and taste, and generated a lemon flavor. A total gingerol content of fresh and fermented ginger was 100.19 mg% and 89.55 mg%, respectively. Sixty-one volatile components in the fresh and fermented ginger were identified, and constituted eight kinds of monoterpenes, twenty-one kinds of sesquiterpenes, eight kinds of oxygenated monoterpenes and nine kinds of oxygenated sesquiterpenes. The most abundant volatile component identified in the fresh ginger was $\alpha$-gingerberine (26.52%), whereas fermented ginger was increased in its alcohol components.

• Asian Journal of Atmospheric Environment
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• v.11 no.1
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• pp.37-53
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• 2017

The effectiveness of four air fresher (AF) systems was evaluated with respect to their removal efficiencies against offensive odorants. For this purpose, malodorous species were generated by exposing freshly cooked foods emitting odorants with levels moderately above their respective threshold values in a confined room. The deodorization efficiency of the four AF systems was then tested for a period of 30 min by estimating the extent of reduction in odorant levels after the operation of each AF. The removal efficiency of the four AF units against each odorant was evaluated as follows: (1) between AF products from different manufacturers, (2) between odorants and ultrafine particulate matter ($PM_{2.5}$), and (3) between operation and natural degassing. The average sorptive removal of odorants was generally <80% and considered less effective or non-effective relative to $PM_{2.5}$. Further examination of odor reduction, if evaluated in terms of odor indices like odor intensity (OI) and odor activity value (OAV), recorded a mean of 33% and 87%, respectively. The overall results of this study confirmed that all tested AF units were not effective to resolve odor problems created under our testing conditions.