• Food Science of Animal Resources
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• v.36 no.1
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• pp.23-28
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• 2016

This study investigates the effect of cooking, storage, and reheating conditions on the formation of cholesterol oxidation products (COPs) in pork loin. Samples of pork loin procured 24 h postmortem were initially processed and assessed for total fat and cholesterol content. The cooking methods evaluated were pan roasting, steaming, oven grilling, and microwaving. Cooked pork loin samples were stored at 4℃ and reheated after 3 and 6 d of storage using the original method of preparation or alternately, microwaving. Fat content increased significantly with cooking as a result of the loss in moisture but cholesterol content remained unchanged. Pan roasting and microwave cooking caused a significantly higher production of COPs, as with the process of reheating using microwave, pan roasting, and oven grilling methods. The major COPs found in pork loin were cholestanetriol, 20-hydroxycholesterol, and 25-hydroxycholesterol, whose concentrations varied according to the different cooking and reheating methods used. Moreover, the aerobic storage of cooked pork loin under a refrigerated condition also increased the formation of cholesterol oxides on reheating.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.220-224
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• 1993

Antioxidative activities of brown materials extracted from the three kinds of roasted coffee beans by water were examined. Antioxidative activity was assessed by the AOM at $120^{\circ}C$ and the oven test at $60^{\circ}C$ on lard. The brown materials of them showed the considerable antioxiant activity. The brown materials of Colombian coffee beans were more effective than those of Robusta or Brazil beans. The antioxidative activities of brown materials from Colombian coffee beans roasted at $210^{\circ}C$ increased in proportion to the browning intensity up to 16 minutes of roasting time, but the antioxidant activities of the brown materials upon further roasting time decreased gradually. In changes of extraction temperature from $30^{\circ}C\;to\;180^{\circ}C$ on the coffee beans roasted at $210^{\circ}C$ for 16 minutes, the antioxidative activities of brown materials did not change as the extraction temperature increased to $180^{\circ}C$. The antioxidative activities of the coffee extracts were thought to be caused by browning reaction materials produced during the roasting process only.

• Resources Recycling
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• v.25 no.5
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• pp.57-63
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• 2016

This study were carried out sulfation roasting and selective leaching test for the effective recovery of copper component in concentrate obtained by froth floatation of Autrallian low grade copper ore. The optimum conditions of sulfation roasting were temp. $450^{\circ}C$, $Na_2SO_4$ 2 mole ratio and time 1.5 h, and then selective leaching were room temperature and $H_2O$ or 1M $H_2SO_4$ solutions. Leaching efficiency of optimum sulfation product were 90 wt.% of copper, 20 wt.% of iron and 15wt.% of nickel elements. In this results, it was possible to selective decomposition leaching of the copper component under optimum conditions in this research.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.312-320
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• 2019

This study examines the changes in chlorogenic acid (CGA), an antioxidant, and one of its decomposition substances, caffeic acid, at various roasting stages and extraction conditions. Based on the CGA content for each roasting stage, at $3^{\circ}C$ after the beginning of the $1^{st}$ crack, the CGA decreased for washed beans and natural beans by more than 50% compared to that of green coffees. The CGA continued to decrease sharply by more than 75% at the end of the $1^{st}$ crack for washed beans and at $5^{\circ}C$ after the end of the $1^{st}$ crack for natural beans. At the peak of the $2^{nd}$ crack, it had decreased by more than 90% for both beans. The Caffeic acid content gradually increased for both washed and natural beans, then rapidly increased from the beginning of the $2^{nd}$ crack to the peak of the $2^{nd}$ crack. However, its contents were very small in quantity. Additionally, the content of CGAs for differing extraction conditions were in the order of 3-CGA, Crypto-CGA, and Neo-CGA. Crypto-CGA content was about half that of 3-CGA and Neo-CGA content was approximately 100 ppm less than that of Crypto-CGA. This study was conducted in order to help make coffee that has the most antioxidant effect.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.739-744
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• 1998

Changes of volatile flavor compounds in sesame oil during industrial process (roasting temp. $225{\pm}2^{\circ}C$, roasting time 15 min) were investigated. Total volatile flavor compounds of 1 st expressed oil from roasted sesame seeds were 536.3 ppm, and those of 2nd expressed oil from sesame seed cake, residue of 1st expression, were 266.8 ppm. Those of 1st filtered oil, fixed oil and 2nd filtered oil were 472.2 ppm, 472.4 ppm and 443.0 ppm, respectively. Volatile flavor compounds were gradually decreased during processing. Top notes $(peak{\;}No.1{\sim}26)$ playing an important role in the aromatic character of sesame oil, of 2nd expressed oil were markedly reduced (70.67% of initial content). Especially pyrazine compounds showed the largest reduction in 2nd expressed oil. Total volatile flavor compounds of fixed oil, filtered oil were reduced slightly.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.5
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• pp.655-660
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• 2003

Flavor components of dry shrimp, roasted-dry shrimp and roasted-dry shrimp with corn oil (w/w: 10%, 25%) were investigated to evaluate the effects of added corn oil on the formation of volatile components in dry shrimp during roasting process. The identified volatile included 20 nitrogen-containing compounds (7 pyrazines, 7 pyridines 3 pyrroles, others) 14 aldehydes, 5 alcohols, 4 ketones and 11 others. The largest quantities of lipid-derived products hexanal, nonanal, 2-pentylfuran, 1-octen-3-ol, trans-2-decenal, trans, cis-2,4-decadienal, trans, trans-2,4-decadienal were detected in the roasted-dry shrimp samples with corn oil. The lipid-derived aldehydes might be involved in the formation of 3- ethyl-2,5-dimethylpyrazine, 2,3,5-trimethyl-6- ethylpyrazine, 2-ethyl-5,6-dimethylpyrazine, 2,3,5- trimethylpyrazine, 3- ethyl-2,6-dimethylpyridine, 2-propylpyridine, ben-zopyrrole and the others. The nitrogen-containing compounds seem to be a major flavor component and responsible for characteristic flavor in roasted-dry shrimp with corn oil.

• Resources Recycling
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• v.32 no.1
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• pp.42-49
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• 2023

The glass ceramic secondary resource containing Li-Al-Si is used in inductor, fireproof glass, and transparent cookware and accounts for 14% of the total consumption of Li, which is the second most widely used after Li-ion batteries. Therefore, new Li resources should be explored when the demand for Li is exploding, and extensive research on Li recovery is needed. Herein, we recovered Li from fireproof Li-Al-Si glass ceramic, which is a new secondary resource containing Li. The fireproof glass among all Li-Al-Si glass ceramics was used as raw material that contained 1.5% Li, 9.4% Al, and 28.9% Si. The process for recovering Li from the fireproof glass was divided into two parts: (1) calcium salt roasting and (2) water leaching. In calcium salt roasting, a sample of fireproof glass was crushed and ground below 325 mesh. The leaching efficiency was compared based on the presence or absence of heat treatment of the fireproof glass. Moreover, the leaching rates based on the input ratios of calcium salt, Li-Al-Si glass, and ceramics and the leaching process based on calcium salt roasting temperatures were compared. In water leaching, the leaching and recovery rates of Li based on different temperatures, times, solid-liquid ratios, and number of continuous leaching stages were compared. The results revealed that fireproof glass ceramics containing Li-Al-Si should be heat treated to change phase to beta-type spodumene. CaCO₃ salt should be added at a ratio of 6:1 with glass ceramics containing Li-Al-Si, and then leached 4 times or more to achieve a recovery efficiency of Li over 98% from a solution containing 200 mg/L of Li.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.465-469
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• 2015

An analysis of changes in herbal tea composition according to the difference in processing conditions showed slightly reduced crude protein content and increased, moisture, crude fat and solid elution rate after treatment using the ash puffing process compared to roasting. Benzopyrene content was significantly reduced to 0.18 ppb from 0.51 ppb. This result indicated that, the $B({\alpha})P$ content differed depending on the processing condition and raw materials. Generation of food $B({\alpha})P$ is mainly include the thermal decomposition of food cooking, when the processing which is a main component of food carbohydrate, protein, fat reason despite severe heat treatment as a whole is to be detected even though the $B({\alpha})P$ in this way is considered to be. The taste, aroma and color did not show a large difference, but the strong bitters taste decreased.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.700-704
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• 2004

Chinese-style pork jerky is a typical intermediate moisture meat product obtained by curing, drying and roasting pork samples. The chemical, physical and microbiological characteristics of pork jerky were evaluated throughout processing. The moisture content varied from 72.5% to 23.4 or 19.6% and aw varied form 0.97 to 0.74 or 0.72 in accordance with processing steps. The pork jerky roasted at $200^{\circ}C$ had higher shear value than roasted at $150^{\circ}C$ because the moisture content and aw of the former sample was lower than the later sample. The nitrite losses during whole processing steps amount to nearly 50%. The TBA value of pork jerky varied from 0.34 to 9.25 or 9.83 mg of malonaldehyde depended on processing steps. The VBN value of pork jerky ranging from 0.25 to 22.4 or 23.5 mg/kg depended upon processing steps. The ATPase activity of myofibrillar proteins during processing steps were partly or entirely denatured by the heat-drying or heat-roasting treatment. A gradual decrease in microorganism count during processing of pork jerky was also observed.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.06a
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• pp.201-201
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• 2020