• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.304-310
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• 2011

To evaluate the effect of curing treatment using a newly developed simplified curing unit (SCU) on the physicochemical quality of stored sweet potatoes was investigated for six months. The SCU consisting of a heater, an air circulation fan, exhaust fans, and a humidifying duct was installed in a cold storage room where the harvested sweet potatoes were stacked. During the six days of curing treatment, air temperature and relative humidity in the storage room were set at $32^{\circ}C$ and 90%, respectively. Physical and chemical properties of sweet potatoes were measured at 1-month intervals from the first day of storage. McKinney index showing the incidence and severity of decay was 0.83% in the curing treatment, while that of untreated control was 5.08% over the same storing period. Firmness, soluble solids content, and dry matter content in the cured sweet potatoes were greater than those of untreated control. Moreover, the changes of skin color in uncured potatoes occurred rapidly than cured one which showed delay of skin discoloration during the long-term storage. Results suggest that the SCU treatment improves the physicochemical quality of stored sweet potatoes and extends their storability. Therefore, the SCU can be effectively used for curing treatment of sweet potatoes with a relatively low cost.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.21-27
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• 2005

To improve Dongchimi (watery radish kimchi) quality and preservation, 0, 3, 5, 10, and 15% of gatt (Brassica juncea; leaf mustard) per radish was added. Chemical characteristics were determined during fermentation at $10^{\circ}C$ for 45 days. Total acidity increased slowly by addition of gatt during initial fermentation period, and 15% treatment showed lowest total acidity. Total vitamin C content increased initially in all treatments depending on gatt content, and decreased thereafter. Period for reaching maximum value was delayed by addition of gatt. Highest total vitamin C was found in 15% treatments. In the case of reducing sugar, 5% treatment showed highest contents. Lactic, succinic, and tartaric acid contents consistently increased during fermentation, while those of malic and citric decreased. Turbidity and total solid contents of Dongchimi liquid increased in all treatments as fermentation proceeded, although the extent was rather suppressed by addition of gatt. Colorimetric lightness values decreased, while the initial increased and then decreased in redness and yellowness. Addition of gatt at above 15% weight level per radish accelerated fermentation at the later fermentation stage thus it should be avoided. Most changes in typical characteristics of fermentation were similar depending on treatments. More acceptable Dongchimi could be prepared by fermenting at 5% gatt concentration under given conditions.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.49-54
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• 2007

The effects of hydrostatic pressure (HP) treatment on the physicochemical, morphological, and textural properties of bovine semitendinosus (ST) muscle were assessed. Based on SDS-PAGE, the decrease in HP-treated ST muscle protein solubility in 0.1 M KCl buffer (pH 7.0) was attributable to a reduction in the levels of sarcoplasmic protein, and the protein solubility decrease observed in 0.6 M KCl buffer (PH 7.0) was attributable to a reduction in the levels of myosin heavy-chain and actin. Scanning electron microscope (SEM) observations showed that muscle fibers became finer and more compact with increasing pressures. The shear force and hardness of ST muscle pressurized to 300 MPa decreased significantly (p<0.05), however samples pressurized at 100 and 500 MPa exhibited a significant increase in both attributes relative to the control sample (p<0.05).

• Food Science of Animal Resources
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• v.43 no.4
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• pp.580-593
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• 2023

The purpose of this study was to analyze whether seawater has positive effects on appearance characteristics, such as CIE a^*, and to determine the gas composition concentration that is suitable for maintaining it. Pork hind meat was cured with four types of curing agent for 5 d at 4℃. The different curing agents comprised the control salt, control nitrite pickling salt (CN), treatment brine, and treatment bittern (BT). The cured hams were cooked at 65℃ for 4 h and packaged at O₂:N₂ gas ratios of 7:3, 8:2, and 9:1 for 3 wk. The physicochemical properties were assessed immediately after heating the sample, and the color properties were measured after a 3 wk storage period. Based on the correlation results of the physicochemical properties, BT had a higher curing and cooking yield than the other treatments, owing to its high salinity. Results of color properties for BT (7:3) and CN (8:2) showed similar color CIE L^*, CIE a^* chroma, and hue angle values. Therefore, BT can be said to be a sous-vide curing agent suitable for preserving the color of ham, and a high nitrogen concentration of 30% helps to maintain the appearance of seawater sous-vide ham.

• Korean journal of food and cookery science
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• v.15 no.1
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• pp.61-67
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• 1999

The effects of salting methods on Kakdugi (cubed radish kimchi) fermentation were evaluated. Kakdugi was prepared with various salting methods, salt concentrations, and settling times, and fermented at 10$^{\circ}C$ for up to 52 days. Radish (Raphanus sativus L.) cubes (2 cm size) were salted by using the following methods salt concentration of about 1.5% which was known appropriate for the organoleptic quality of Kakdugi: 1) Treatment S-1: applying dry salt uniformly onto the radish cubes, with a salt concentration of about 1.5% (w/w) and cured for 1 hr, 2) Treatment S-5: applying dry salt uniformly onto the radish cubes, with a salt concentration of about 1.2% (w/w) and cured for 5 hr, 3) Treatment B-1: brining radish cubes in a 8.5% (w/v) salt solution for 1 hr, 4) Treatment B-5: brining radish cubes in a 4.0% (w/v) salt solution for 5 hr. As the fermentation continued, the initial high decrease in pH has been retarded in all the treatments, of which the delaying extent was more significantly noted from B-1 and B-5 than S-1 and S-5. The pH of the Kakdugi which showed a good eating quality dropped to 4.3∼4.8 with the accumulation of total acids. Total vitamin C increased sharply at the palatable period of Kakdugi during the initial fermentation and then decreased gradually following a sigmoidal changing pattern. The reducing sugar levels were also influenced by salting methods and fermentation as sugars are converted into acids. High initial contents of reducing sugars and their subsequent rapid decrease were observed in “S” group than “B” group during fermentation. For nonvolatile organic acids, lactic acid increased consistently throughout the fermentation while malic acid, which was high at the initiation of fermentation, decreased rapidly afterwards at the palatable period of Kakdugi.

• Culinary science and hospitality research
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• v.23 no.8
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• pp.98-105
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• 2017

The purpose of this study was to investigate changes in physicochemical properties of apples pre-treated differently with salt and sugar for apple Jangachi. When salt was used, moisture content was decreased by 28.41% to 57.67% at 24 hours and maintained an average 56.92% after 24 hours. However, when sugar was used, moisture content decreased steadily to 41.14% (60h). The pH of the apple pre-treated with salt decreased from pH 4.42 to pH 3.63 at 12 hours. However, in the case of apples pre-treated with sugar, pH decreased from pH 4.52 to pH 4.19 after 48 hours, but was not statistically significant. Conversely, total acidity of apple pre-treated with salt increased from 11.46% to 0.35% during 72 hours. But total acidity of apple pre-treated with sugar decreased to 0.11% at 24 hours and maintained. Sugar content of apple pre-treated with salt increased to 33.1% at 12 hours and maintained. Conversely, in case of sugar pre-treatment, sugar content of apple pre-treated with sugar increased steadily to 45.12% at 72 hours. Salinity of apple pre-treated with salt increased sharply to 15.74% during 24 hours. Lightness ($L^*$) of apple pre-treated sugar was not different from the control group. But apple pre-treated salt decreased slightly. Yellowness ($b^*$) was higher than the control group regardless of pre-treatment group. Sensory evaluation revealed that sugar pre-treatment apples were highly evaluated for flavor, taste, chewiness and overall acceptance.

• Food Science of Animal Resources
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• v.36 no.1
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• pp.8-13
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• 2016

This study investigated the effect of soy protein hydrolysates (SPH) prepared by varying subcritical media on the physicochemical properties of pork patties. For resource of SPH, two different soybean species (Glycine max Merr.) of Daewonkong (DWK) and Saedanbaek (SDB) were selected. SPH was prepared by subcritical processing at 190℃ and 25 MPa under three different of media (water, 20% ethanol and 50% ethanol). Solubility and free amino group content revealed that water was better to yield larger amount of SPH than ethanol/water mixtures, regardless of species. Molecular weight (Mw) distribution of SPH was also similar between two species, while slightly different Mw distribution was obtained by subcritical media. For pork patty application, 50% ethanol treatment showed clear red color comparing to control after 14 d of storage. In addition, ethanol treatment had better oxidative stability than control and water treatment based on thiobarbituric acid-reactive substances (TBARS) analysis. For eating quality, although 20% ethanol treatment in SDB showed slightly higher cooking loss than control, generally addition of SPH did not affect the water-binding properties and hardness of pork patties. Consequently, the present study indicated that 50% ethanol was the best subcritical media to produce SPH possessing antioxidant activity, and the SPH produced from DWK exhibited better antioxidant activity than that produced SDB.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.224-232
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• 2015

The effects of cold plasma (CP) treatments on the physicochemical and biodegradable properties of a corn biomass-containing polyester (CBPE) film were studied. The CBPE film was treated with CP generated by $N_2$, $O_2$, He, Ar, or dry air at 400-900 W and 667 Pa for 10-40 min. The glass transition temperature of the CBPE film ($-30.2--28.6^{\circ}C$) was not affected by the CP treatment, while the elastic modulus and water vapor permeability decreased (p<0.05). The ink printability was improved by the treatment and the improved printability was maintained during storage for 56 days at room temperature. Roughness of the film increased after treatments and the level of roughness appeared to increase during storage. Heat and microbial biodegradability of the CBPE film was improved by the air-CP treatment (p<0.05). These results have demonstrated the potential of applying CP treatments to improve the flexibility, printability, and biodegradability of CBPE films.

• Food Science of Animal Resources
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• v.42 no.3
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• pp.441-454
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• 2022

This study aimed to determine the effect of enzyme, guar gum, and pressure processing on the digestibility and physicochemical properties of age-friendly liver sausages. Liver sausages were manufactured by adding proteolytic enzyme (Bromelain) and guar gum, and pressure-cooking (0.06 MPa), with the following treatments: control, without proteolytic enzyme; T1, proteolytic enzyme; T2, proteolytic enzyme and guar gum; T3, pressure-cooking; T4, proteolytic enzyme and pressure-cooking; T5, proteolytic enzyme, guar gum, and pressure-cooking. The pH was high in the enzyme- and pressure-processed groups. The pressure-processed groups had lower apparent viscosity than other cooking groups, and it decreased during enzyme treatment. Hardness was lower in the enzyme- and pressure-processed groups than in the control, and the T4 was the lowest. Digestibility was the highest in T4 at 82.58%, and there was no significant difference with that in T5. The general cooking group with enzyme and guar gum also showed higher digestibility than the control (77.50%). As a result of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the enzyme- and pressure-treated groups (T4, T5) were degraded more into low-molecular-weight peptides (≤37 kDa) than the control and other treatments. Viscoelasticity showed similar trends for viscous and elastic moduli. Similarly, combined pressure processing and enzymatic treatment decreased viscoelasticity, while guar gum increased elasticity but decreased viscosity. Therefore, the tenderized physical properties and improved digestibility by enzyme and pressurization treatment could be used to produce age-friendly spreadable liver sausages.

• Food Science of Animal Resources
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• v.43 no.3
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• pp.428-440
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• 2023

Global meat consumption is increasing worldwide, however, supply remains lacking. Several alternative protein sources, such as cultured meat, plant-based protein production, and edible insects, have been proposed to overcome this shortage. Interestingly, edible insects are characterized by superior digestive and absorptive qualities that make them the ideal replacement for traditional protein production. This study aims to further the processing ability of insect protein by investigating the effects of various pre-treatment methods, such as blanching (HB), roasting (HR), and superheated steam (HS), on the nutritional properties and physicochemical characteristics of proteins extracted from Hermetia illucens larvae. The drying rate, pH value, color analysis, amino and fatty acid profile, as well as bulk density, shear force, and rehydration ratios of the above pre-treatment methods, were explored. HS was found to have the highest drying rate and pH value analysis showed that HB and HS samples have significantly higher values compared to the other modalities. Raw edible insects had the highest value in the sum of essential amino acid (EAA) and EAA index when compared to EAAs. HB and HS showed significantly lower bulk density results, and HS showed the highest shear force and the highest value in rehydration ratio, regardless of immersion time. Therefore, taking the above results together, it was found that blanching and superheated steam blanching pre-treatment were the most effective methods to improve the processing properties of H. illucens after hot-air drying.