• Title/Summary/Keyword: Rancidity

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Quality Characteristics of Citron Treated Mackerel Oil and Fillet during Refrigerated Storage (유자액 처리에 의한 고등어유와 필렛의 냉장 저장중 품질 특성)

  • Jung, Bok-Mi;Chung, Gyu-Hwa;Jang, Mi-Soon;Shin, Suk-U
    • Korean Journal of Food Science and Technology
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    • v.36 no.4
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    • pp.574-579
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    • 2004
  • Quality characteristics of citron-treated mackerel oil and fillet during refrigerated storage were evaluated. Citron-treated and non-treated mackerel oil and fillet were estimated by periodical measurements of acid, peroxide, carbonyl, volatile basic nitrogen, trimethylamine-N, and thiobarbituric acid values. Volatile basic nitrogen and trimethylarnine-N values in mackerel fillet treated with citron for 25 days during refrigerated storage were significantly lower than those of citron non-treated mackerel fillet, with those of boiled citron water-treat group significantly decreasing compared to 1 and 2% citron extract groups. Acid, peroxide, carbonyl, and thiobarbituric acid values of citron-treated mackerel oil were significantly lower than those of citron non-treated mackerel oil throughout storage period. Overall acceptability of salted mackerel fillets treated with boiled citron water and 1% citron extract was significantly than those of control and 2% citron extract. Results indicate application of citron juice on mackerel surface may be useful to lower rancidity degree and fish odor during refrigerated storage.

Studies on the Preservation of Korean Rice by Gamma-irradiation(II) On disinfestation of rice by gamma-ray irradiation (감마선 조사에 의한 쌀 저장에 관한 연구 (제 2 보))

  • Kim, Hyong-Soo;Choi, Young-Rack;Kim, Sung-Kih;Harn, In-Ja
    • Korean Journal of Food Science and Technology
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    • v.2 no.1
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    • pp.104-112
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    • 1970
  • Korean Paldal variety rice, harvested November and hulled into polished and unpolished forms in April, 1969, packed in the straw bags and the kraft paper bags. Being irradiated with 10, 30 and 50 krad ${\gamma}-ray$, the samples were stored at room temperature for testing infestation, uric acid content, fat acidity, riboflavin content and panel test. The results are as follows. 1. The kraft bag lot with polished rice or unpolished rice manifested the apparent disinfestation with $30{\sim}50$ krad irradiation. On the other hand, in the straw bag lot the irradiation effects on disinfestation were weakened through summer on account of the second contamination. 2. The changes of uric acid content in rice were proportional to the state of infestation. 3. Fat acidity, which has a close relation with the rancidity of fat in rice, increased during storage and showed some increasing tendency in the irradiated lot with $30{\sim}50$ krad. 4. In comparison with the control lot, riboflavin content was not affected by 50 krad irradiation. 5. With 10, 30 and 50 krad dose, the irradiated lot should have no significant difference in taste, odour, color and viscosity for the panel test.

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Studies on Lipids and Proteins of Rabbit Meat -I. Emphasis on lipid component of rabbit meat- (토끼고기의 지방질과 단백질에 관한 연구 -I. 지방성분을 중심으로-)

  • Leekim, Yang-Cha;Ahn, Hong-Seok
    • Journal of Nutrition and Health
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    • v.10 no.2
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    • pp.18-26
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    • 1977
  • Among animals, the rabbit is known to be affected most sensitively by dietary changes and to be most susceptible to atherosclerosis. The exact reason is still unknown as to whether the primary cause is intrinsic (tissue itself) or extrinsic such as a blood factor which could be influenced by various dietary means. It is of utmost importance to check the nutritional quality of rabbit meat before it is accepted and adapted as a daily food item. To evaluate nutritional quality of rabbit meat, studies on various aspects of lipid components were carried out in comparison with other animal meats such as beef, pork and chicken also included in the study was the question whether the cooking and storage conditions influence the composition of fatty acids and cholesterol level. Some results and findings are listed below: 1. The content of linoleic acid (18 : 2), one of the essential fatty acids, was much higher in rabbit meat compared to the other meats. The Percentages of this Polyunsaturated fatty acids, was much higher in rabbit meat compared to the other meats. The percentages of this polyunsaturated fatty acid in terms of total fatty acids were $37.3{\pm}3.7$, 5.9, 14.5, and 21.9% for rabbit, beef, pork, and chicken respectively. The degree of unsaturation was high not only in meat but also in liver and adipose tissue of rabbit. The values of iodine number, the indication of degree of unsaturation, were known to be $102{\sim}107$, $32{\sim}47$, $46{\sim}67$, and $55{\sim}77$ for rabbit, beef, pork, and chicken respectively. Such a high proportion of this polyunsaturated fatty acid contained in rabbit meat could be harmful due to their Peroxidation effect. 2. A small amount of lower (short chain) fatty acids was isolated from rabbit tussues, which were not observed in other animal's tissues. The significance of this small amount of short chain fatty acids contained in rabbit meat remained an open question. 3. The concentration of total cholesterol in rabbit meat was similar to that of otherr but the content of esterified cholesterol was higher in rabbit meat. This was probably due to the perference of cholesterol to esterify with unsaturated fatty acids. By roasting the percentage of Polyunsaturated fatty acids was decreased while saturated palmitic acid was proportionally increased. 4 The composition of fatty acids were affected more by dry heat than moist heat. More research should be pursued to improve methods of preservation and storage to prevent possible peroxidation and rancidity problems of rabbit meat. In the meantime, the public should be informed to eat fresh rabbit meat and not to store it for a long period of time. This study was supported by the Ministry of Science and Technology in Korea.

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Physicochemical Properties of Oat (Avena sativa) Flour According to Various Roasting Conditions

  • Lee, In-Sok;Song, Young-Eun;Han, Hyun-Ah;Song, Eun-Ju;Choi, So-Ra;Lee, Ki-Kwon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.62 no.1
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    • pp.32-39
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    • 2017
  • This study was performed to investigate the physicochemical properties of raw and roasted oats for the production of processed goods. Changes in particle size, pH, moisture content, Hunter b value, polyphenols, proteins, flavonoids, lipid rancidity, ${\beta}-glucan$ content and sensory evaluation were compared between raw and roasted hulled oats (HO) and de-hulled oats (DO) after heating treatment at 0, 80, 120, 160 and $200^{\circ}C$. HO was more finely crushed than DO. The Hunter b value of HO was lower than that of DO, which increased sharply at $200^{\circ}C$. The pH range was from 6.2 to 6.6, with an average value of 6.4. In contrast to the protein contents of the two oat types, polyphenol content showed gradual decrease as roasting temperature increased. A comparison of the flavonoid content of HO with DO, indicated difference in the increase of flavonoids with increasing temperature. The protein content of HO was observed to be higher than that of DO. Furthermore, the protein level was slightly increased with increasing temperature. Malonidialdehyde (MDA) content was statistically identical from $0^{\circ}C$ to $160^{\circ}C$, but then increased sharply at $200^{\circ}C$. As expected, the ${\beta}-glucan$ content of HO was higher than that of DO. The ${\beta}-glucan$ content of HO was decreased at $80^{\circ}C$, but increased from $120^{\circ}C$ to $200^{\circ}C$. In contrast, the ${\beta}-glucan$ of DO increased constantly compared to the control. Variations in sensory characteristics such as color, taste, smell and overall preference were observed. There were statistically significant difference among the sensory characteristics of the two oat types heated at $0^{\circ}C$ and $120^{\circ}C$ and at $160^{\circ}C$ and $200^{\circ}C$ (p<0.05). Our collective results, including those for particle size, MDA, protein, ${\beta}-glucan$ content and sensory evaluation, indicated that HO would be more useful in the development of processed goods than DO, and that an optimum temperature for roasting oats is approximately $160^{\circ}C$ for 15 min. Moreover, our results indicate that suitable roasting temperatures and cultivars are necessary to produce high-quality processed oat goods.

Quality Characteristics of Kwamegi (Semi-dried Coloabis saira) During Cold Air Drying after Washing with Various Washing Solutions (살균소독수로 세척한 후 냉풍건조한 꽁치과메기의 품질특성)

  • Kang, Sang-Mo;Lee, Won-Young
    • Journal of Food Hygiene and Safety
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    • v.30 no.1
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    • pp.74-80
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    • 2015
  • In this study, the microbial control effect after treatment of washing solutions (tap water, electrolyzed water, chlorine dioxide solution) and quality changes were investigated when Kwamegi is produced by means of the cold air drying. The initial moisture rate of the sample was 56.62% before drying. At the beginning of drying period, moisture rate sharply fell down but as the experiment progressed, moisture reducing rate was smoothly decreased. The color difference of Kwamegi before drying was 42.40, but it was reduced depending on the increment of drying temperature and time. TBA value of the initial sample was 0.219, rancidity were increased continuously when drying progressed. Total amino acid content was showed the highest value at $25^{\circ}C$ for 36h and the lowest at $40^{\circ}C$ for 12h. From the fatty acids analysis, major fatty acids were consisted of the 14:0, 16:0 and 18:1 (18.1520.96%, 28.0632.51% and 17.0619.81%, respectively). The microbial control effect was biggest when Kwamegi was washed with chlorine dioxide 100ppm for 60s. The microbe of the Kwamegi, Pseudomonas sp. and Pseudomonas putida were identified.

A Study on Nutritional Evaluation about Commercial Korean Traditional Foods (시판 한국전통음식의 영양학적 연구)

  • 계승희
    • Journal of Nutrition and Health
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    • v.20 no.6
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    • pp.395-404
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    • 1987
  • A nutritional quality and rancidity of marketed korean traditional foods were assessed. That is, basic chemical analysis were done in Galbi-tang, Sullung-tang, Pibimbap, Pulkogi and Naeng Myon. Ca and P for the Galbi-tang and Sulung-tang and vitamin C for the Pibimbap were analyzed. Chemical analysis were done in Gangjung 4, Sanja 1, Parksan 6, Yoomilkwa, 4 out of korean traditional cookies. Amounts of energy and protein in Galbi -tang and protein and Ca in Sullung -tang are more than the recommended allowance at ta meal. Amounts of Ca in Galbi-tang and energy in SUllung-tang are less than the recommended . The amounts of energy and protein in Pibimbap, Pullkigi and Naeng Myon Except protein in Pullkogi are short of the recommended at a meal. And amounts of vitamin C in Pibimbap are short of the recommended, too. The content of carbohydrate in Korean traditional cookies is the highest one comparing to others. Contents of crude fat in Gangjung Parksan and Dasik which are made up of sesame, black sesame and pine nuts are higher than that of other Korean traditional cookies. Acid value and peroxide value in all Gangjung, Yoomilkwan and Sanja except the peroxide value in one Sanja product, are not in the excess of standard of peroxide value and acid value. The standard are 600meq/kg and 3 for peroxide value and acid value respectively in oil treated foods.

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Effect of Salicornia herbacea L. Powder on the Quality Characteristics of Bread (함초 분말 첨가가 식빵의 품질 특성에 미치는 영향)

  • Bae, Jong-Yoon;Park, La-Young;Lee, Shin-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.9
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    • pp.1196-1201
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    • 2008
  • This study was carried out to investigate the effects of Salicornia herbacea L. powder (SHP) on white bread quality. Crude fiber, crude ash, Fe and Ca contents of bread with SHP were higher than those of control and increased with increasing SHP concentration. The pH of bread with SHP was higher than that of without SHP. Salinity of bread prepared with SHP (0.6, 1.2, 1.8, and 2.4%) did not show any significant difference compared with control. L and b value of the bread were decreased by the addition of SHP. The inside color of SHP (1.8%) added bread did not show significant difference compared with control. The texture (hardness, chewiness, cohesivness, and springiness) of bread prepared with SHP was higher than that of without SHP. DPPH-radical scavenging activity of SHP added bread (0, 0.6, 1.2, 1.8, 2.4, and 6.0%) was 27.95, 30.42, 33.91, 39.51, 41.17 and 63.82%, respectively. DPPH-radical scavenging activity was increased significantly by the addition of SHP. Inhibition of lipid rancidity and total polyphenol contents of the breads were increased by the addition of SHP.

Dehydration of Foamed Fish(Sardine)-Starch Paste by Microwave Heating 2. Quality Stability and Shelf-life of the Product (어육(정어러) 발포건조제품가공에 관한 연구 2. 제품저장중의 품질변화와 저장기간)

  • LEE Kang-Ho;LEE Byeong-Ho;SONG Dong-Suck;You Byeong-Jin;LEE Byeong-Ho;SUH Jae-Soo;JEA YOi-Guan;RYU Hong-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.4
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    • pp.291-297
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    • 1982
  • In this part of the studies on dielectric dehydration of foamed fish-starch paste, qualify stability and shelf-life of the product of which the preparation formula and processing conditions were described in previous report (Lee et al, 1982) were determined by means of accelerated reaction test. The product was stored for 50 days under the conditions of temperatures at 35, 45, and $55^{\circ}C$ in steady state and various water activities of 0.44, 0.52, 0.65, and 0.75, respectively. The loss of available lysine, extent of TBA value, and development of browning during the storage were measured and reaction kinetically analysed to assess quality stability and shelf-life of the product for the storage at room temperature of $25^{\circ}C$. Extent of browning was accelerated with the increase of water activity and temperature marking the time to reach a limit of color and flavor deterioration, or to reach brown color density of 0.17 O.D./g at 420 nm, 106 days at aw=0.44, $35^{\circ}C$, and 41 days at aw=0,65, $55^{\circ}C$, These reaction rates resulted in a prediction of shelf-life, 130 to 110 days in the storage at aw=0.44 to 0.75, $25^{\circ}C$. The quality limit assessed by TBA values and sensory evaluation of rancidity was 87 days at aw=0.44, $35^{\circ}C$, and 30 days at aw=0.75, $55^{\circ}C$ which gave a predicted shelf-life, 128 to 113 days . at aw=0.44 to 0.75, $25^{\circ}C$ storage.

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Effects of Oleoresin Spices on the Quality of Chicken Surimi during Frozen Storage (Oleoresin 향신료의 첨가가 계육 Surimi의 냉동저장중 품질에 미치는 영향)

  • 이성기;민병진;강창기
    • Food Science of Animal Resources
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    • v.21 no.4
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    • pp.292-299
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    • 2001
  • Chicken surimi from mechanically deboned chicken meat was prepared with 0.2% oleoresin spices such as rosemary, thyme, sage, mace, marjoram, and bay. Samples were stored at -18$\^{C}$ for 14 weeks to observe quality change including lipid oxidation, color and textural properties. The pH of surimi decreased from pH 7.44∼7.58 stored at 1 day to pH 7.03∼7.13 stored at 14 weeks. The control surimi showed higher level of pH during storage periods. Color stabiilty of surimi decreased during frozen storage both in control and oleoresin added surimi. Control surimi comparatively maintained higher color stability during frozen storage because of higher L* and a* values, and lower b*. On the contrary, the marjoram addition significantly decreased L* and a* value, and increased b* value compared with other oleoresins. Therefore, the color of surimi seems to be affected original color of oleoresin spice itself. Gel strength showed loser level in oleoresin added surimi than control surimi. Oleoresin spices inhibited lipid oxidation significantly because less thiobarbituric acid-reactive substance(TBARS) were accumulated in oleoresin added surimi than control surimi. Sage was the most effective in minimizing lipid oxidation in frozen surimi as TBARS of sage added surimi stored for 14 weeks maintained only 42% compared with that of control. In conclusion, the 6 kinds of oleoresin in this experiment retarded oxidative rancidity in chicken surimi but there was no beneficial effect on the surface color and gel strength.

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Evaluation of the quality stability on the soybean flour depending on storage conditions

  • Park, Sung-Kyu;Son, Na-Young;Kim, Mi-Jung;Chung, Ill-Min
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.264-264
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    • 2017
  • Legumes are good sources of various nutrients. Among legumes, soybean and its flour are accessible foods to consumers. However, in case of soybean flour, there is a disadvantage of easily going rancid. Thus, this study aimed to investigate how the quality of soybean flour changes during storage according to the packaging materials and storage temperatures. The raw and roasted soybean flours were packed in two types of packaging, polyethylene (PE) and polypropylene (PP) film bags respectively, and stored at three different storage temperatures (4, 20, and $45^{\circ}C$) for 1 year. The acid value, conjugated diene value, peroxide value, p-anisidine value, thiobarbituric acid (TBA) value, lipoxygenase activity, and fatty acid content of raw and roasted soybean flours were measured at the point of starting storing, and after 1, 2, 4, 8, and 12 weeks of storage. The acid value of soybean flour was increased for 4 weeks and thereafter significantly decreased (p < 0.0001). The conjugated diene value was significantly increased after 4 weeks storage at $45^{\circ}C$ with PE and PP film bags (p < 0.0001). The peroxide value had no changes during 4 weeks storage at $45^{\circ}C$ with PE and PP film bags, and then those was dramatically increased after 8 weeks (p < 0.0001). The p-anisidine values in all of storage conditions were decreased after 4 weeks. Lipoxygenase activity was decreased at 12 weeks storage at $20^{\circ}C$ and $45^{\circ}C$ with PP film bags. Acid value had positive correlations with p-anisidine value (r = 0.30 and p < 0.0001) and lipoxygenase activity (r = 0.36 and p < 0.0001), and had negative correlations with conjugated diene value (r = -0.45 and p < 0.0001) and peroxide value (r = -0.25 and p < 0.001). Conjugated diene value had a high positive correlation with peroxide value (r = 0.76 and p < 0.0001), but that had a negative correlation with lipoxygenase activity (r = -0.51 and p < 0.0001). Peroxide value had negative correlations with p-anisidine value (r = -0.20 and p < 0.01) and TBA value (r = -0.15 and p < 0.05). The degree of reduction in fatty acid content of raw soybean flour was higher than the roasted soybean flour during the storage. Total fatty acid content had positive correlations with acid value (r = 0.45 and p < 0.0001) and p-anisidine value (r = 0.58 and p < 0.0001), but had a weak negative correlation with conjugated diene value (r = -0.19 and p < 0.01). This study showed how the rancidity of the raw and roasted soybean flours progressed during storage. Thus, our findings can be used as base data to do a further study of finding and developing more stable storage conditions of the soybean flour.

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