• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1137-1143
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• 1999

The change of physicochemical characteristics of sesame with roasting temperature$(110^{\circ}C{\sim}230^{\circ}C)$ were investigated to get a useful index which needs to manufacture roasted sesame and sesame oils, In the physicochemical properties of roasted sesame, the contents of moisture, specific volume, oil yields and sesame cakes were changed significantly above $170^{\circ}C$. Fat and protein in sesame cakes were changed slightly. Desirable roasting temperature was $220^{\circ}C$ in considering oil yields and sensory qualities. Total amino acids such as arginine, serine, threonine, lysine. cystine, tyrosine and most of the free amino acids, and sucrose of free sugars were reduced significantly above $170^{\circ}C$ and $190^{\circ}C$. respectively. These reductions of sugar and amino compounds were assumed to play an important role in Maillard reaction for the formation of browning pigment, taste and aroma. It was confirmed that this reaction was pyrolytic degradation which took place in water-deficient and oil-rich system at relatively high temperature.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.250-254
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• 1994

The quality characteristics of freeze-dried Chungkook-jang soup, stored at $25^{\circ}C$, $35^{\circ}C$ and $45^{\circ}C$ was investigated. Peroxide value(POV) was increased as the storage time was extended. Browning reaction occured earlier in the sample stored at $45^{\circ}C$ than those stored at $35^{\circ}C$ and $25^{\circ}C$. Red color developed more intensely in the sample stored at $45^{\circ}C$. However, moisture content was not changed during storage. Regression analyses between sensory scores and quality characteristics showed that the peroxide formation of oil contained in Chungkook-jang soup was the major quality index for the deterioration of Chungkoak-jang soup.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1339-1351
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• 2020

Objective: It is well recognized that beef cuts from a low quality grade are usually associated with tougher, drier and less flavorful. Thus, the present study aimed at investigating the combined effects of postmortem ageing and sous vide (SV) cooking followed by oven roasting or blowtorching on the eating quality of low quality grade Hanwoo beef striploins. Methods: Hanwoo beef striploins (quality grade 3) obtained from 36 month-old Hanwoo steers were used, and the samples were chiller aged for 0 and 14 d at 4℃. After ageing, the samples were prepared into 2.5-cm steaks which were then SV cooked at 55℃ for 5 h and then raised to 60℃ for 1 h, and thereafter the SV-cooked the steaks were further roasted in oven for 20 min (SV+OV) or blowtorched (SV+TC) for 2 min. The cooked samples were analyzed for microbiological quality, browning index, Wanrner-Bratzler shear force (WBSF), aroma flavor compounds and sensory properties. Results: The SV cooking significantly reduced the WBSF values in beef samples (p<0.05). Blowtorching after SV cooking led to a browner surface of the beef steaks (p<0.05). The samples treated with SV+OV or SV+TC exhibited higher levels of Maillard reaction-derived aroma flavor compounds such as; pyrazines and sulfur-containing compounds compared to those just SV cooked. More especially, the SV+OV- or SV+TC- treated samples presented significantly higher flavor and overall acceptability scores compared to those just SV cooked (p<0.05). Ageing beef for 14 d significantly improved the tenderness by reducing the WBSF and increasing the tenderness scores. Conclusion: Thus, the combination of postmortem ageing and SV cooking followed by additional treatments (blowtorching or oven roasting) could be used to improve the eating quality especially tenderness and flavor as well as overall acceptability of low grade Hanwoo beef.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.766-772
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• 2008

The objective of this investigation was to develop iced cookies with freeze-dried yellow onion powder (YP) and red onion powder (RP) at composition levels of 0, 1, 3, 5 and 10%. The moisture (13.61%) and crude ash contents (3.43%) of YP was higher than RP, while the crude protein (7.58%) and crude fat contents (0.65%) of RP was higher than YP. Freeze-dried YP showed a higher lightness and yellowness value compared to RP, because of the unique color of the onion. The browning index was lower in YP. The pH of the dough significantly decreased by addition of onion powder, while the density of the dough was significantly increased in RP samples than the others. The iced cookies showed a lower lightness value, and a higher redness value with increase of onion powder contents. Hardness of YP cookies up to 5% and RP cookies up to 3%, were lower compared to the control. With regards to the sensory characteristics, $3{\sim}5%$ YP cookies and 3% RP cookies were more acceptable than the others. As a result, the optimal ratio of freeze-dried YP and RP iced cookies were calculated at 5% YP and 3% RP levels.

• Food Science and Preservation
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• v.15 no.3
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• pp.347-351
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• 2008

The effect of microperforated packaging films on fresh-cut apples was studied Apples (Malus domestica Borkh. cv. Red Delicious) were cored and cut, packaged in laser microperforated film or non-microperforated polyolefin film, and stored for 3 weeks at 4C. The flesh firmness of apples packaged in microperforated film during the storage period was significantly higher than that of apples packaged in non-microperforated film, and the level of soluble solids was also higher. The browning index, titratable acidity, pH, acetaldehyde and ethanol levels were not affected by microperforation. These results show that microperforated films could be used for retention of flesh firmness in fresh-cut apples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.211-217
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• 2000

To standardize quality characteristics of commercial doenjang prepared by traditional method, general components, organic acids, amino acids and fatty acid composition were investigated. Moisture, crude protein, crude lipid, titratable acidity (expressed as milliliter of 0.1 N NaOH), acid value and salinity were 54.7%, 13.8%, 8.0%, 14.4mL, 45.7mg/g and 11.8%, respectively. The content of amino type nitrogen was 345.3mg% (w/w) in the range of 207.6 to 443.5mg% being 1.1~2.2-fold for all samples. Average value of Hunter color for L(lightness), a(redness) and b(yellowness) were 37.4, ＋9.7 and ＋21.3, respectively. Browning index value(expressed as optical density at 425 nm) of water-soluble compound(2.58) was above 7.1 times higher than that of the water-insoluble compound(0.38). Total contents of free and total amino acid were 3.81 and 9.72%, respectively, and then the former(1.1~3.7 times) was more different in all samples tested than that of the latter(1.1~2.0 times). Among amino acids, glutamic acid was abundant and its content of free and total amino acids was 0.57 and 1.24%, respectively. Of organic acids, lactic acid was the most abundant being 0.34%(average) and ranged from 0.15 to 0.86%. Linoleic acid(52.17%, as area%) was the highest content of the total fatty acids. Unsaturated and polyunsaturated fatty acids were 83.89 and 61.189%, respectively. Polyunsaturated fatty acid was markedly different among all samples and ranged from 51.52 to 64.91%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.2
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• pp.121-128
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• 2022

The aims of this study were to optimize the processing procedure of high-quality semi-alternating temperature dried Israeli carp Cyprinus carpio (SAD-IC) and to investigate the sensory properties of the product. Based on the differences in moisture content of the dorsal and ventral muscles, high quality SAD-IC was prepared by alternating the drying temperature between 4 h at 35℃, and 2 h at 5℃, three times before final drying for 2 h at 35℃. The surface in SAD-IC produced under the optimal alternating-temperature drying process had a markedly superior browning index value and softer texture compared to products produced using constant-temperature drying. SAD-IC produced from dorsal and ventral muscle had significantly superior taste values than the raw material. These results suggest that SAD-IC has the potential to be industrialized.

• Korean Journal of Remote Sensing
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• v.40 no.1
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• pp.9-18
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• 2024

Small streams, despite their rich ecosystems, face challenges in vegetation assessment due to the limitations of traditional, time-consuming methods. This study presents a groundbreaking approach, combining unmanned aerial vehicles(UAVs), convolutional neural networks(CNNs), and the vegetation differential vegetation index (VDVI), to revolutionize both assessment and management of stream vegetation. Focusing on Idong Stream in South Korea (2.7 km long, 2.34 km² basin area)with eight diverse revetment methods, we leveraged high-resolution RGB images captured by UAVs across five dates (July-December). These images trained a ResNeXt101 CNN model, achieving an impressive 89% accuracy in classifying vegetation cover(soil,water, and vegetation). This enabled detailed spatial and temporal analysis of vegetation distribution. Further, VDVI calculations on classified vegetation areas allowed assessment of vegetation vitality. Our key findings showcase the power of this approach:(a) TheCNN model generated highly accurate cover maps, facilitating precise monitoring of vegetation changes overtime and space. (b) August displayed the highest average VDVI(0.24), indicating peak vegetation growth crucial for stabilizing streambanks and resisting flow. (c) Different revetment methods impacted vegetation vitality. Fieldstone sections exhibited initial high vitality followed by decline due to leaf browning. Block-type sections and the control group showed a gradual decline after peak growth. Interestingly, the "H environment block" exhibited minimal change, suggesting potential benefits for specific ecological functions.(d) Despite initial differences, all sections converged in vegetation distribution trends after 15 years due to the influence of surrounding vegetation. This study demonstrates the immense potential of UAV-based remote sensing and CNNs for revolutionizing small-stream vegetation assessment and management. By providing high-resolution, temporally detailed data, this approach offers distinct advantages over traditional methods, ultimately benefiting both the environment and surrounding communities through informed decision-making for improved stream health and ecological conservation.

• Food Science and Preservation
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• v.31 no.2
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• pp.235-244
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• 2024

A nonthermally sterilized raw apple vinegar was manufactured using an ultra-fine filtration process (0.2 ㎛ membrane filter) and its quality was comparable to commercially available vinegar products. First, using apple concentrate as a raw material, it was possible to produce non-thermal sterilized Using a two-stage fermentation process of alcohol and acetic acid fermentations, a non-thermally sterilized raw apple vinegar with pH 2.94 and an acidity of 6.20% was produced from an apple concentrate. The fermentation process increased the browning index significantly. However, the fundamental quality parameters of the non-thermal sterilized raw apple vinegar (A) with sterilized apple vinegar (B) did not differ significantly. The pH (2.92-2.95) of apple vinegar (A and B) was higher than that (pH 2.65-2.70) of commercial vinegar (C and D), and the total acidity, which is in the range of 6.20-6.21% and 6.53-6.90%, respectively, was higher in samples C and D than in samples A and B. However, four kinds of organic acids were detected in non-thermal sterilized raw apple vinegar (A), and its total organic acid content (6,245.00 mg%) was significantly higher than that of other samples (B, C, D) (p<0.05). In particular, malic acid content, as a main organic acid in apples, was very high in sample (A) (244.83 mg%) and sample (B) (210.21 mg%), compared to commercial products C (125.78 mg%) and D (86.90 mg%). The total polyphenol content and antioxidant activity of fermented apple vinegar (A, B) were more than twice as high as those of commercial products (C, D). Vinegar A had higher total polyphenol content than vinegar B. The above results suggest it is possible to manufacture and commercialize non-thermal sterilized raw apple vinegar with higher organic acid content and antioxidant properties using ultra-fine filtration.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.745-751
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• 2015

This study was performed to investigate the quality characteristics such as pH, total acidity, browning index, 5-hydroxymethylfurfural (5-HMF), fructose, S-allyl-L-cysteine (SAC), total polyphenol, and DPPH radical scavenging activity of aged garlic at different aging temperatures and periods. Aging temperature and period had a significant (p<0.05) effect on the quality characteristics of garlic. The pH in aged garlic significantly (p<0.05) decreased with increasing aging temperatures and periods, while the total acidity, browning index, and 5-HMF levels increased. The 5-HMF levels in garlic aged at 60 and $70^{\circ}C$ increased from 0.08~3.30 and from 0.05~106.07 mg/100 g, respectively. The fructose content in garlic aged at $60^{\circ}C$ gradually increased from 0.77 to 14.57%, while that of garlic aged at $70^{\circ}C$ increased from 1.07 to 19.75% until day 30, after which it decreased. The SAC level in raw garlic was 47.09 mg/100 g. The SAC contents of aged garlic differed significantly according to aging temperature and period. The SAC levels in garlic aged at $60^{\circ}C$ and $70^{\circ}C$ were in the range of 15.28~100.5 and 12.41~85.55 mg/100 g, respectively. The total polyphenol contents of garlic aged at $60^{\circ}C$ and $70^{\circ}C$ were 6.01 and 6.67 fold higher, respectively, than those in raw garlic. The DPPH radical scavenging activity of aged garlic also showed a tendency to increase during aging.