• Food Science of Animal Resources
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• v.41 no.2
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• pp.214-223
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• 2021

This study compared the quality, cooking, textural, and palatability characteristics between sous-vide (SV) cooked pork loin patties with different searing treatments (ST). Before SV cooking, STs were conducted on each side of the pork loin patties for 0 (control) to 120 s (ST120), and all patties were then cooked using an SV cooker at 75℃ for 120 min. Noticeable differences were observed in quality properties between the groups. The seared SV loin patties exhibited lower lightness and higher browning index values compared to the unseared SV loin patties (p<0.001). Cooking loss gradually increased with increasing ST times, and the control group had a lower percentage compared to the ST60 group (19.5 vs. 25.7%, p<0.001). Changes in cooking properties were associated with the extent of ST, and the ST groups exhibited a higher hardness value compared to the control group (p<0.001). Regarding palatability, loin patties from the control group scored lower in appearance acceptability compared to patties from the ST groups (p<0.05) due to extent of browning on the surface. Moreover, the ST groups did exhibit a higher flavor intensity compared to the control group, but no differences were observed in tenderness and juiciness scores between the control and ST60 groups. Due to these results, the ST60 group exhibited a greater score in overall acceptability compared to the other groups except for the ST90 group. Therefore, an additional ST before SV cooking can achieve a more appealing appearance and palatability as well as to enhance the availability of pork loin.

• Food Science and Preservation
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• v.16 no.6
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• pp.797-803
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• 2009

The effects of drying methods on the browning and moisture sorption characteristics of Rubus coreanus were studied. Fruits were steamed for 5 min at $100^{\circ}C$, dried by sun drying, infrared drying, or freeze drying, and powdered to a size of 20 mesh. Color values were measured and equilibrium moisture contents (EMC) were determined at $20^{\circ}C$, over a range of water activity ($a_w$) from 0.11 to 0.90. The browning indices $L^*$ and $a^*$ values were higher and lower, respectively, in freeze-dried Rubus coreanus compared with other samples. The $b^*$ value was greatest in freeze-dried Rubus coreanus. EMC tended to increase with increasing $a_w$ values, and a particularly sharp increment was observed above 0.75 $a_w$. The EMC of freeze-dried Rubus coreanus was significantly higher compared with the EMC of sun-dried and infrared-dried fruit at constant aw. The moisture sorption isotherms showed a typical sigmoid shape, and the Halsey, Kuhn, and Oswin models were the best fits for the sun-dried, infrared-dried, and freeze-dried powder isotherms, respectively. With respect to monolayer moisture content, the Guggenheim-Anderson-Boer (GAB) equation showed that the various drying methods yielded very different results, with monolayer moisture contents of 0.005 g $H_2O/g$ dry solid in infrared-dried and 0.019 g $H_2O/g$ dry solid in sun- and freeze-dried powders, respectively. These results indicate that the drying method affects the browning and moisture sorption characteristics of Rubus coreanus.

• Journal of Mushroom
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• v.15 no.4
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• pp.195-201
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• 2017

We measured the antioxidant activities of Oak mushroom (Lentinula edodes) in browned sawdust medium under conditions of varying LED sources and amounts of light. Consequently, exposure to 200Lx blue LED resulted in highly efficient browning; the most efficient browning was shown at 200Lx, regardless of the type of luminous source. We identified that quantities obtained with the blue luminous source increased compared to those in other treatment plots. The DPPH radical scavenging test conducted to examine antioxidant activity revealed that the red luminous source caused high radical scavenging compared to efficient browning. The fruiting body for Nongjin-go, as a treatment plot with the highest scavenging, under a 400Lx red luminous source was $34.3{\pm}1.80%$ and that for 'Sanjo 701' at a 300lx red luminous source was $32.99{\pm}1.58%$. The polyphenol content, reported to be correlated with DPPH radial scavenging, showed no similar correlation in the 'Nongjin-go' variety. By contrast, 'Sanjo 701' showed a similar association.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.291-297
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• 2000

Oleoresin was extracted from fresh garlic by microwave-assisted extraction (MAE) and its functionality and antibrowning effect were investigated at various extraction conditions. The yield and polyphenol contents of the garlic oleoresin were inversely related to extraction time. The highest yield was l2.9% and maximum polyphenol contents was 574.3 mg% when the oleoresin was extracted for 5 min with ethanol. Apparently, the electron donating abilities of garlic oleoresin increased with extraction time, but there were no significant differences among extraction time intervals. The highest nitrite scavenging effect was found at pH 1.2 and decreased as pH increased. Tyrosinase inhibitory effect was less than 30% for most garlic oleoresin but the 15 minute extraction with ethanol resulted in higher inhibitory effect. Angiotensin I-converting enzyme (ACE) inhibitory effect was highest (89.2%) when oleoresin extracted with ethanol for 20 min. The addition of cysteine, ascorbic acid and citric acid to oleoresin extracts retarded browning action of garlic oleoresin during 10 day storage. 0.1 % cysteine retarded browning reaction and some synergistic effect was found in the combination of citric acid and ascorbic acid.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.283-291
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• 2006

This study examined the development of a low-salt fermented seafood product using an ascidian (Halocynthia roretzi), and the optimum processing conditions and quality characteristics of the low-salt fermented ascidian (LSA). The optimum processing conditions for the LSA were as follows. The ascidian was shelled and its muscle sliced into 5 mm widths. This was soaked in a 10% salt and 1% sodium erythorbate solution for 20 min. The solution was drained and then the muscle was soaked in 0.1% sodium bisulfite solution for 1 min. To this was added a 1:1 mixture of anchovy sauce and rice gruel, and it was fermented at $5^{\circ}C$ for 15 days. The moisture content and salinity of the LSA were 75.0-75.4% and 8.0-8.5%, respectively. During salt-fermentation at $5^{\circ}C$ for 20 days, the amino-N content of the LSA increased, and the texture softened gradually. The viable cell counts in early salt-fermentation were $4.2-4.5{\times}10^4CFU/g$, and this decreased gradually. The ratio of saturated fatty acids tended to increase in early salt-fermentation, while that of polyunsaturated fatty acids decreased slightly. Chemical experiments and sensory evaluation showed that the dipping treatment in 1% sodium erythorbate solution and 0.1% sodium bisulfite solution resulted in a good color and prevented browning of the salt-fermented ascidian meat. Moreover, adding anchovy sauce and rice gruel mixture improved the flavor of the LSA.

• Journal of Biosystems Engineering
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• v.40 no.1
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• pp.61-66
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• 2015

Purpose: The purpose of this study was to establish conditions to dry a radish by examining the drying and quality characteristics depending on the air temperature and velocity of a far infrared conveyor dryer. Methods: A sample of weighing 6 kg was dried until the moisture content reached $15{\pm}0.5%$ (w.b.). Four temperatures (50, 60, 70, and $80^{\circ}C$) and three air velocity levels (0.4, 0.6, and 0.8 m/s) were employed as the drying factors. Results: The drying rate increased with the increase in the temperature and air velocity but decreased with time. However, the drying rate was influenced by temperature rather than velocity. At a temperature $50^{\circ}C$ with a air velocity of 0.4 m/s, it took 350 min for the radish to dry which was the longest drying time; $80^{\circ}C$ with a air velocity of 0.8m/s, it took 180 min for the radish to dry, which was the shortest drying time. ${\Delta}E$ (the color difference value) increased with the increase in temperature and air velocity. The browning and rehydration ratio increased as the temperature rose. Energy consumption decreased with the increased temperature and air velocity. Conclusions: Based on the results of this study, the best drying conditions for the radish were determined to be a temperature of $70^{\circ}C$ with an air velocity of 0.8 m/s.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.487-493
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• 1993

The changes of cooked rice stored in an electric rice cooker at different temperature were investigated using sensory and mechanical methodology. The desirability of cooked rice was deteriorated during storage, particulary cooked rice stored at $80^{\circ}C$ had the lowest desirability. As the storage time increased, glossiness, clumpiness, adhesiveness, moistness and sweet flavor of cooked rice decreased but browning and off-flavor increased. The higher storage temperature resulted in the lower in glossiness, firmness, cohesiveness, moistness, sweet flavor and in the more browning, adhesiveness and off-flavor. L and b values measured by Hunter Color Difference Meter were highly correlated with the sensory glossiness and color.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.176-180
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• 1987

The sorption characteristics of dried garlic flakes stored at various relative humidity and storage temperature were studied. At low relative humidity below RH 51%, the sorption equilibrium was easily attained, whereas at higher relative humidity above RH 67%, the flakes were browned by higher equilibrium moisture content. The flakes were browned at relative humidity above 67% at $20^{\circ}C$ and $35^{\circ}C$, above 84% at $5^{\circ}C$, respectively. The moisture contents of monolayer value for the flakes were ranging from 5.80% to 6.20% (DB) with varying temperatures. And the necessity of moisture-proof packaging material suggested for the long term storage of the flakes because the lower moisture content and storage temperature, the higher driving force of wetting. Regression equation for browning rate prediction with relative humidity and storage temperature of the flakes was determined.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.537-542
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• 1987

Antioxidative characteristics and it's related substances of fermented soybean sauce in lipid oxidation process were studied. Soybean sauce was prepared according to various periods of fermentation, and model systems were made of cooked ground meat with soybean sauce of various levels of combination (1/10,2/10,3/10,4/10,5/10 in system) and various fermentation periods (0,2,4.6 months). During the storage for 5 weeks at $6^{\circ}C$, antioxidative activities of soybean sauce in the systems were increased with the increase of concentration and fermentation period of soybean sauce. And also in the comparison of the antioxidative effect on the compositions of total phenol content, Maillard browning reaction products and free amino acids in the soybean sauces of the various fermentation periods, the browning products were considered as the major antioxidative substances in soybean sauce.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.287-296
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• 2010

This study was designed to investigate the influence of the pH and enantiomer on the antioxidant activity of Maillard reaction mixture solution in model systems. The loss of glucose in MRPs did not show different characteristics for the different amino acid enantiomers; however, the concentration of glucose decreased as the pH levels increased. The enolization of sugars was observed in all MRP samples according to increase of pH levels. In addition, D-amino acids were detected in L-amino acid systems and L-amino acids could also be observed in D-amino acid systems. Formation of the isomer was the highest in the Glc/L-Lys system. The browning development increased as pH levels increased; however, browning development did not show different characteristics based on the use of L- versus D-isomers of the same amino acid. The L- and D-isomers show different absorption values in the UV-Vis spectra, but the absorption patterns display a similar shape. The antioxidant activities of MRPs derived from the Glc/Gly, Glc/L-Asn and Glc/D-Asn systems at pH 7.0 were greater compared to those of pH 4.0 and pH 10.0. The antioxidant activities of MRPs derived from the Glc/L-Lys and Glc/D-Lys systems decreased as the pH increased. In addition, the results show that the MRPs derived from the D-isomers have similar antioxidant activities as those from L-isomer. Therefore, the MRPs have the different antioxidant activities on the basis of the pH level, but not on the basis of different amino acid enantiomers.