• Food Science and Preservation
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• v.20 no.1
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• pp.14-22
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• 2013

The effects of the initial storage temperature and the PA film packaging on the extension of the shelf-life and the improvement of the postharvest storage quality of muskmelons were studied during their storage. Their storage quality was tested as follows: PA-film-wrapped muskmelons, stored at $2^{\circ}C$ or $7^{\circ}C$ for 30 days after their harvest, were kept at $10^{\circ}C$ for 27 days (total: 57 days). On the fifth day of storage at $10^{\circ}C$ (35th day overall), the weight loss reached 6.4% in the 7-control. However, the 2-PA showed the smallest loss of 2.2%. The soluble solids content and the acidity that were measured before the storage were $10.8^{\circ}Brix$ and 0.26% in all the groups. After 27 days of storage at $10^{\circ}C$ (on the 57th day overall), the values were highest in the 2-PA group with $9.7^{\circ}Brix$ and 0.15%, respectively. Microorganisms were not detected at first; but on the fifth day of storage at $10^{\circ}C$ (35th day overall), their values were 3.87 and 2.68 log CFU/g in the seven-control and the 2-PA, respectively. In other words, the 2-PA was found to be more effective in inhibiting microbial proliferation. In relation to sensory properties such as appearance, flavor, sweetness and chewiness, the 2-PA was superior to the other groups and was found to be most effective in improving the storability of muskmelons. In conclusion, it was found that low-temperature injury and fast storage quality deterioration did not occur in film-wrapped muskmelons that were stored at $2^{\circ}C$ for 30 days after they were harvested.

• Food Science and Preservation
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• v.23 no.5
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• pp.623-630
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• 2016

Inappropriate storage of fresh-cut onions may result in losses of good quality. To understand storage conditions for shelf-life and quality of fresh-cut onions, The effect of packing type and storage temperature on the quality of fresh-cut onions was evaluated. Onions stored at $0^{\circ}C$ for 2 months were peeled off after removing root and shoot parts. Each three peeled onions were packed in a polyethylene film (PE, $50{\mu}m$) or in a polyethylene/polypropylene film (PE/PP, $100{\mu}m$) with vacuum treatment (70 cmHg) and stored at different temperatures (4, and $10^{\circ}C$) for 21 days. The following analyses were examined to evaluate the quality of fresh-cut onions: microbial population, surface color, titratable acidity and pH, respiration rate, and sensory quality. Fresh-cut onions stored at $4^{\circ}C$ showed less aerobic and coliform bacterial population than those stored at $10^{\circ}C$ during observation periods. Fungal populations of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased significantly after 13 days. E. coli was not detected in all treatments during whole storage periods. Surface colors of fresh-cut onions were not affected by packing type and storage temperature, however, color difference (${\Delta}E$) of fresh-cut onions in PE/PP film stored at $10^{\circ}C$ was significantly higher than those of other treatments. Titratable acidity of fresh-cut onions was not affected by packing type and storage temperature. However, pH of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased gradually over the whole storage period. Fresh-cut onions packed in PE film showed higher $CO_2$ and less $O_2$ concentrations at $10^{\circ}C$ than those at $4^{\circ}C$. The sensory quality of fresh-cut onions was significantly affected by packing type and storage temperature after 13 days. Particularly, vacuum treatment in PE/PP film showed better sensory quality than that of PE film package at the same storage temperature. It was concluded that vacuum treatment and storage at $4^{\circ}C$ could be effective to prolong the quality of fresh-cut onions up to 21 days.

• Food Science and Preservation
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• v.10 no.2
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• pp.154-157
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• 2003

To examine the quality changes of three typical fishes under usual storage conditions during marketing, we determined the total bacterial counts and pH values during storage of mackerel, croaker, and saury. Mackerels were stored at 0$^{\circ}C$ and on ice at 19$^{\circ}C$, which is the usual storage condition in a local market and croakers and saury were stored at 0$^{\circ}C$ and 4$^{\circ}C$. Total bacterial counts of mackerel, croaker, and saury were 3,2${\times}$10$^3$, 2.9${\times}$10$^3$, and 2.8 x 10$^4$CFU/g at the time of storage respectively. Total bacterial counts of mackerel stored on ice at 19$^{\circ}C$ increased during storage and reached to 8.4 x 10$\^$6/ CFU/g at day 6, while those stored at 0$^{\circ}C$ decreased up to 2 days of storage and increased to 5.6 ${\times}$ 10$^4$CFU/g. For croaker and saury, total bacterial counts at 0$^{\circ}C$ were 2.5 ${\times}$ 10$\^$5/ and 2.1 x 10$\^$5/ CFU/g at day 6, respectively, while those stored at 4$^{\circ}C$ had 3.6 x 10$\^$6/ and 2.6 ${\times}$ 10$\^$5/ CFU/g. the pH value or mackerel was 5.56 at the time or storage, yet it increased to 6.04. The pH changes of croaker and saury had a similar pattern with that of mackerel, which increased with time of storage. These results suggest that storage of fishes at 0$^{\circ}C$ should be better than those at 4$^{\circ}C$ or on ice at 19$^{\circ}C$ in terms of microbial safety as well as quality and shelf-life of fishes.

• Food Science and Preservation
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• v.22 no.1
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• pp.36-43
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• 2015

The edible crab is among the rich resources that can be used as materials for food products, but living crabs and crabs marinated in soy sauce are the only widely utilized materials for food products. For seafood development, research is needed to promote the use of crabs in various products. In this study, the quality changes of fried rice prepared with crab meat, crab emulsion sauce and crab cooker effluent were investigated. The pH and acidity values did not show any significant difference at $-20^{\circ}C$. The acidity of the fried rice continuously increased during storage at 4 and $25^{\circ}C$. The VBN and TBA values of the fried rice stored at 4 and $25^{\circ}C$ were significantly higher than those of the fried rice stored at $-20^{\circ}C$ during the storage period. The viable cell count of the fried rice stored at $-20^{\circ}C$ changed little during the storage period while that of the fried rice stored at 4 and $25^{\circ}C$ rapidly increased over 2 weeks. For the fried rice stored at $-20^{\circ}C$, the overall quality did not show significant differences during the storage period. In conclusion, the best storage temperature for both quality and safety was found to be $-20^{\circ}C$. At such storage temperature, the quality of the stored instant rice using crab meat did not change, and through research the expanding possibilities of using crab materials were confirmed.

• Food Science and Preservation
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• v.17 no.6
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• pp.784-792
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• 2010

Mild heat treatment was applied to ginger rhizomes to achieve shelf-life extension for fresh minced ginger. The rhizomes were treated at 45, 50, 55, or $60^{\circ}C$ for different periods of time, minced, and stored at $10^{\circ}C$ for 9 days. Microbial levels in minced fresh ginger decreased with increases in temperature and duration of heat treatment. The non-treated and treated samples did not significantly differ in color at the initial stage of storage. Changes in color were detected after 3 days, and accelerated after that time. The ${\Delta}E$ value of control samples reached 12.42, whereas that of treated samples (except when $45^{\circ}C$ was applied for 60 min) ranged from 7.67 to 10.96, after 9 days. There was no significant difference in initial pH value between control (pH 6.09) and treated (pH 6,046.20) samples. The pH of control samples increased to 8.02 after 9 days, whereas pH values of samples treated at $50^{\circ}C$ and $60^{\circ}C$ ranged from pH 6.807.83 after 9 days. The percentage of control drip was 25.65% at the initial stage of storage, which was lower than those of treated samples. Drip increased to 38.63% in the control and to 34.20~38.44% in treated samples after 9 days. The sensory characteristics of the control samples were similar to those of treated samples at the initial stage of storage. After 6 days, the control and some treated samples developed off-flavors and discoloration. However, samples treated at $50^{\circ}C$ for 60 min retained favorable quality characteristics for 9 days after storage.

• Food Science and Preservation
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• v.16 no.5
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• pp.605-611
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• 2009

Korean Baechu cabbage(known as Chinese cabbage) brined in 0%, 5% and 10% (all w/v) salt solutions were packed using high-density polyethylene film (HDPE-film), low-density polyethylene film (LDPE-film), or Mirafresh film (MF-film, US patent No. 5972815), and stored at 4C for 4 weeks. Changes in pH and salinity, and microorganism counts (lactic acid bacteria and total bacteria), were investigated. There was no significant difference in the pH change in cabbage stored using various films when the vegetables were not salted. However, the pH was most stable in Baechu cabbage prepared using 10% salt solution. Cabbage treated with 0%, 5%, and 10% salt showed salinity values of 0.83%, 1.17% and 1.62%(all w/w), respectively, after 4 weeks of storage by LDPE-film. When cabbage was treated with the highest concentration of salt solution, the count of lactic acid bacteria increased but that of total bacteria decreased. The pH from pH 6.10 to pH 4.32, pH 5.68, and pH 5.92 in brined cabbage packed in HDPE-film, LDPE-film, and MF-film, respectively, after 4 weeks. When MF-film was used, the pH showed the greatest stability of all films tested, regardless of the concentration of salt solution employed in brining. The counts of lactic acid bacteria and total bacteria increased by all tested films during storage. Cabbage packed by MF-film showed the lowest increase in bacterial counts. In conclusion, MF-film was found to be the most effective packaging material for Baechu cabbage and brining in 10% salt solution was optimal to enhance the shelf life of the vegetable. LDPE-film was more effective than was HDPE-film for storage of brined cabbage.

• Food Science and Preservation
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• v.24 no.6
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• pp.734-745
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• 2017

The effects of combination treatment with sulfur dioxide generating pad ($SO_2$ pad) and modified atmosphere packaging (MAP) on grape quality were examined under simulated exporting condition and actual export to Los Angeles, USA. The 'Campbell Early' grape harvested in Hwaseong, Gyeonggi was precooled at $0^{\circ}C$, selected and packaged at $10^{\circ}C$, and stored at $0^{\circ}C$ for 30 days. The treatment was as follows: general export packaging (control), only $SO_2$ pad, combination of $SO_2$ pad and MAP (perforated polyethylene film, $SO_2$ pad+MA). In case of control and only $SO_2$ pad under simulated exporting condition, the grape quality changes with storage time were decrease in hardness and brush length, increase in stem browning, and increased in shattering rate. The treatment of $SO_2$ pad+MA was the most effective in preserving the grape quality since $SO_2$ concentration inside the package remained around 2.9 ppm by MA film. Grape exports from harvest to local distribution of the USA took 30 days, and only $SO_2$ pad+MA package showed no fungus, maintained brush length and rachis color, and was lowest at 4.0% of shattering rate since the concentration of $SO_2$ in the package was about 4.0 ppm. As a result, it was considered that the combination of $SO_2$ pad and MA was the most effective way to maintain freshness of grape during long-term marine transportation and extend the shelf-life in exporting countries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.35-41
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• 2006

Antibacterial activities of the trace elements in combination with the food additives were measured against 6 kinds of food-borne microorganisms such as Escherichia coli, Vibrio parahaemolyticus, Staphylococcus aureus, Bacillus cereus, Bacillus subtilis and Pseudomonas fluorescens. The difference of antibacterial activity was not shown among the kinds of food additives, such as dextrin, gelatin and collagen. Zn and Ge in combination with food additives had strong antibacterial effect. Especially, $1\%$ zinc acetate in combination with $1\%$ gelatin was more effective against P. fluorescens and S. aureus than against Bacillus sp., E. coli and V. parahaemolyticus. Minimum inhibitory concentration of zinc acetate in combination with $1\%$ gelatin appeared to be 0.5 mg/mL on S. aureus and P. fluorescens, and 1.0 mg/mL on E. coli, V. parahaemolyticus, B. cereus and B. subtilis. Minimum bactericidal concentration of zinc acetate in combination with $1\%$ gelatin appeared to be 0.5 mg/mL on P. fluorescens and 1.0 mg/mL on E. coli, V. parahaemolyticus, S. aureus, B. cereus and B. subtilis. The zinc acetate in combination with gelatin showed stronger inhibitory effect in acidic range below pH 6.0, and remained active even after heat treatment at $121^{\circ}C$ for 15 min. In comparison with control, the viable cell counts of fish pastes, which were coated with the solution containing both $1\%$ zinc acetate and $3\%$ gelatin, were decreased by more than 100-fold until the storage of 7 days at $10^{\circ}C$. The results indicate that the combined use of zinc acetate and some food additives could prolong the shelf life of fish pastes by 8 days or more at $10^{\circ}C$.

• Korean Journal of Poultry Science
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• v.7 no.2
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• pp.37-46
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• 1980

Hand deboned and mechanically deboned chicken meat were produced from domestic broilers and spent layers. Meat yield, chemical composition, functional characteristics, stability during storage, and microbiological properties were investigated Chicken patties and frankfurters were also manufactured by varying the relative proportion of MDCM to HDCM as raw materials, ana their palatability, shelf-life and textural properties were evaluated. The obtained results were as follows: 1) 35% of carcass wt was recovered as HDCM and 45% as MDCM, total meat yield reaching 80% of carcass wt. 2) Moisture, protein, fat, ash and Ca content of MDCM were 65, 12, 20, 1.7 and 0.2-0.4%,respectively. MDCM was higher in fat, ash and Ca, but significantly lower in moisture and protein. Total pigment content of MDCM was 2.5 times higher than that of HDCD such high content being attributed to the increased inclusion of hemoglobin. 3) The emulsifying capacity (ES) of MOCM per g meat was only 70% that of HDCM. but when ES was expressed on unit g of protein basis MDCM showed even higher ES than HDCM primarily due to tile higher proportion of salt soluble protein fraction. 4) Since the TBA values of MDCM increased rapidly after 4 weeks of frozen storage at -20$^{\circ}C$, the maximum possible storage period of MDCM is estimated to be about 4 weeks. 5) Total microbial counts of MDCM was approximately 1.8${\times}$10$\^$6/g/, showing no great difference from HDCM or red meat. 6) Chicken patty containing MDCM showed gradual increase in TBA value during frozen storage, but its storage up to 8 weeks presented no problems in flavor stability. 7) Color score an4 total palatability of chicken Patty were best for the product containing 30% MDCM. It was also concluded that MDCM can be included in the patties up to 50% of total meat with good results, but more than 70% was not recommended 8) The formulation of MDCM up to 50% in frankfurter gave quite satisfactory acceptability and textural properties comparable to frankfurter made of 100% MDCM, but the inclusion of more than 70% MDCM was not recommended 9) The TBA value of frankfurter containing MDCM did not increase to any great extent until 4 weeks of storage at 4$^{\circ}C$, indicating no unique problems in flavor instability compared to regular frankfurter. 10) It was concluded that processed meat products such as patties and frankfurters containing MDCM up to 30-50% of total meat ingredients gave satisfactory results in color, texture and palatability, comparable to regular products.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.20-24
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• 2013

Food irradiation has recently become one of the most successful techniques to preserve food with increased shelf life. This study aims to analyze hydrocarbons in almonds (Prunus amygosalus L.) and peanuts (Arachis hypogaea) induced by electron beam irradiation. The samples were irradiated at 0, 1, 3, 5 and 10 kGy by e-beam and using florisil column chromatography fat, and content was extracted. The induced hydrocarbons were identified using gas chromatography-mass spectrometry (GC/MS). The major hydrocarbons in both irradiated samples were 1,7-hexadecadiene ($C_{16:2}$) and 8-heptadecene ($C_{17:1}$) from oleic acid, 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$) from linoleic acid and 1-tetradecene ($C_{14:1}$) and pentadecane ($C_{15:0}$) from palmitic acid. Concentrations of the hydrocarbons produced by e-beam were found to be depended upon the composition of fatty acid in both almonds and peanuts. The $C_{n-2}$ compound was found to be higher than $C_{n-1}$ compound in oleic acid and palmitic acid, while in case of linoleic acid, $C_{n-1}$compound was higher than $C_{n-2}$ compound. The radiation induced hydrocarbons were detected only in irradiated samples, with 1 kGy or above, and not in the non-irradiated ones. The production of 1,7-hexadecadiene ($C_{16:2}$), 8-heptadecene ($C_{17:1}$), 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$), in high concentration gave enough information to suggest that these may be the possible marker compounds of electron beam irradiation in almonds and peanuts.