• Title/Summary/Keyword: Oxidative stability

Search Result 420, Processing Time 0.022 seconds

Improvement of Low Temperature Property of Biodiesel from Palm Oil and Beef Tallow Via Urea Complexation (요소 착물형성에 의한 포화지방산 고함유 팜유 및 우지 유래 바이오디젤의 저온유동성 개선효과 연구)

  • Lee, Yong-Hwa;Shin, Jung-Ah;Zhang, Hua;Lee, Ki-Teak;Kim, Kwang-Soo;Jang, Young-Seok;Park, Kwang-Geun
    • New & Renewable Energy
    • /
    • v.8 no.4
    • /
    • pp.38-43
    • /
    • 2012
  • Biodiesel is non-petroleum based fuel produced from vegetable oils or animal fats through transesterification. The compositions of saturated and unsaturated fatty acids in the feedstocks are important factors for biodiesel quality in terms of low-temperature fluidity and oxidative stability. The goal of this study is to improve the cold flow property of biodiesel from vegetable and animal origin containing highly saturated methyl esters (approx. 50%). In this purpose poly-saturated methyl esters in palm and tallow biodiesel were removed via urea-based fractionation and then the recovered fractions (enriched unsaturated fatty acid methyl esters) were supplemented with cold flow improvers. The highest concentration of unsaturated fatty acid methyl esters (93.8%) was obtained using a urea/fatty acid ratio of 3:1 at the crystallization temperature of $0^{\circ}C$ for 17 hours in incubation, with recovery of 71% and the addition of cold flow improver (Flozol$^{(R)}$ 515, 3,000 ppm) to the enriched poly-unsaturated fatty acid methyl esters reduced the CFPP(cold filter plugging point) of palm biodiesel from $12^{\circ}C$ to $-42^{\circ}C$. In tallow biodiesel both the enrichment of unsaturated fatty acid methyl esters (93.71%) and the addition of cold flow improver (Infineum R408, 3,000ppm) reduced the CFPP from $10^{\circ}C$ to $-32^{\circ}C$.

Antioxidative Effect of Commercial Lecithin on the Oxidative Stability of Perilla Oil (들기름의 산화안정성에 미치는 레시틴의 산화방지 작용)

  • Ahn, Tae-Hoe;Kim, Jong-Soo;Park, Seong-Joon;Kim, Hyean-Wee;Park, Ki-Moon;Choi, Chun-Un
    • Korean Journal of Food Science and Technology
    • /
    • v.23 no.3
    • /
    • pp.251-255
    • /
    • 1991
  • The antioxidative effects of the six commercial lecithins, tocopherols, citric acid and ascorbyl palmitate on refined perilla oil were inverstigated by active oxygen method ($AOM,\;hrs\;at\;97.8^{\circ}C$) and oven test. Except for the lecithin I (aceton insoluble content 55%), the induction time on perilla oil treated with commercial lecithins at 5% level was longer than that of refined soybean oil. When the concentration of lecithin (0.5, 1, 2.5, 4 and 5%) in perilla oil was increased, enhanced the antioxidative effect at AOM and oven test. Lecithin also showed synergistic effect with the mixtures of tocopherol, citric acid and ascorbyl palmitate. The antioxidative effect of ${\gamma}-rich-tocopherol$ on perilla was higher than that of ${\dalta}-rich-tocopherol$ or mixed tocopherol.

  • PDF

Changes of antioxidative properties according to the heat-treatment of ginger extracts (생강추출물의 열처리에 따른 항산화성 변화)

  • 이진영;안명수
    • Korean journal of food and cookery science
    • /
    • v.10 no.1
    • /
    • pp.63-70
    • /
    • 1994
  • Oleoresin, 6-gingerol and 6,10-gingerol: 6-paradol= 1 : 1 mixture were extracted from ginger (Zingi-her of ficinale Roscoe) and changes of its antioxidant activity by heat-treatment were studed. Oleoresin was extracted with Ethanol-Ether and 6,10-gingerol : 6-paradol(1 : 1) and 6-gingerol were extracted with Hexane and Hexan : Ether= 1 : 1, respectively, and identified on the Thin-layer Chromatograpy (TLC) plate with the solvent system of Hexane Ether(1 : 4, v/v). And oleoresin was heat-treated during 0, 10, 30, 60, 120 minutes, and 6-gingercl and 6,10-gingerol . 6-paradol=1 : 1 were heat-treated during 0, 5, 10, 20, 40 minutes, respectively, at 140$^{\circ}C$ dry oven. To compare with antioxidant activity, oleoresins were added into soybean oil at 3fo level, 6-gingerol and 6,10-gingerol : 6-paradol= 1 : 1 at 0.1% level, BHT and TBHQ at 0.02% level, respectively. All the substrates treated were stored in a incubator at 45 2$^{\circ}C$ condition. The oxidative stability was estimated by the analysises of peroxide value and conjugated diene value during storage. The results were as follows: Antioxidant activity of oleoresins were considerably high and by heat-treatment were not decreased. 6-paradol was not show the antioxidant activity. 6,10-gingerol : 6-paradol=1 : 1 provided poor protection for soybean oil. Antioxidant activity of 6-gingerol was higher than 6,10-gingerol : 6-paradol=1 : 1 and by heat-treat-ment antioxidant activity was directly decreased. Relative antioxidant effectiveness(RAE) of each antio-xidant was compared. RhR was found to decrease as follow : TBHQ>oleoresin》BHT TBHQ》BHT>6-gingerol》6,10-gingerol : 6-paradol=1 : 1.

  • PDF

Effects of Chlorophyll Addition and Light on the Oxidative Stability and Antioxidant Changes of Perilla Oil Emulsion (들기름 에멀젼의 산화안정성 및 산화방지제에 대한 클로로필 첨가 및 빛의 영향)

  • Choe, Jeesu;Choe, Eunok
    • Korean journal of food and cookery science
    • /
    • v.29 no.1
    • /
    • pp.53-62
    • /
    • 2013
  • Lipid oxidation and antioxidants changes in perilla oil emulsion added with chlorophyll were studied during storage in the dark or under 1,700 lux light at $25^{\circ}C$ for 48 h. The emulsion was consisted of perilla oil (33.12 g), 5% acetic acid (66.23 g), egg yolk powder (0.5 g), and xanthan gum (0.15 g), and Chlorophyll b was added to the emulsion at 0, 2.5 and 4 mg/kg. The lipid oxidation was evaluated by headspace oxygen consumption and hydroperoxide formation, and tocopherols and polyphenols were monitored by HPLC and spectrophotometry at 725 nm, respectively. The lipid oxidation of the perilla oil emulsion in the dark was not significant regardless of the addition of chlorophyll. Light increased and accelerated the lipid oxidation of the emulsion, and increased addition level of chlorophyll under light increased it further. However, there was no significant change in fatty acid composition in any case. Contents of tocopherols and polyphenols in the emulsion were not significantly changed during storage in the dark regardless of chlorophyll addition, indicating their little degradation. Tocopherols and polyphenols in the emulsion were significantly degraded during storage of the emulsion under light, and the degradation rate of polyphenols was increased with addition level of chlorophyll. The lipid oxidation of the perilla oil emulsion was inversely related with the residual amounts of tocopherols and polyphenols, with more dependent on the retention of polyphenols than that of tocopherols.

Meat Quality Traits of Longissimus Muscle of Hanwoo Steers as a Function of Interaction between Slaughter Endpoint and Chiller Ageing

  • Dashdorj, Dashmaa;Oliveros, Maria Cynthia R.;Hwang, In-Ho
    • Food Science of Animal Resources
    • /
    • v.32 no.4
    • /
    • pp.414-427
    • /
    • 2012
  • Carcass characteristics and meat quality traits as a function of endpoint months of slaughter age (26 vs 32 mon) and chiller ageing (1 vs 10 d) were evaluated for m. longissmus of 26 Hanwoo steers fed with commercial diets including whole crop barley silage. Totally twenty six Hanwoo steers for 6 mon of age that were fed until 26 mon of age constituted the short term-fed group and fed until 32 mon of age constituted long-term fed group. Carcasses were chilled for 24 h and were graded. Strip loin samples were divided into two age groups (1 d and 10 d). Long-term feeding increased carcass weight, rib-eye area, yield grade, marbling score, firmness and quality grade of the meat. The feeding for 32 mon produced tender, juicy meat (p<0.01) with lower cooking loss and higher rating score (p<0.05) than short term feeding, while other quality traits were not influenced by the length of feeding. Intramuscular fat content and oxidative stability (TBARS value) were significantly (p<0.05) higher in beef from long-term feeding however the length of feeding did not alter the fatty acid composition. Chiller aging reduced instrumental tenderness (WBSF value), improved color, sensory tenderness, acceptability and rating of beef. The results of the present study mirrors that Hanwoo steers until 32 mon of age overall improved carcass traits and palatability compared to that for 26 mon. However, from the viewpoints of economical and environmental aspects, cost of the additional feeding for 6 mon for value-adding of eating quality was relatively high and the effects in turn were limited.

Antioxidative Activity of Some Solvent Extract from Caesalpinia sappan L. (소목 추출물의 항산화 효과)

  • Lim, Dae-Kwan;Choi, Ung;Shin, Dong-Hwa
    • Korean Journal of Food Science and Technology
    • /
    • v.28 no.1
    • /
    • pp.77-82
    • /
    • 1996
  • Antioxidative activity of the extract from Caesalpinia sappan L. by various solvent was compared with several commercial antioxidants, using the Rancimat method. AI (antioxidative index; induction period of oil containing extract/induction period of control oil) of all extracts were higher than commercial antioxidants, such as BHA, ${\delta}-tocopherol$ and ascorbic acid. The ethanol extract was fractionated by liquid liquid extraction. Ethyl acetate fraction showed higher AI than the whole crude extract. When comparing POV and TBA value of palm oil and lard containing different level of each fraction, the oxidative stability of ethyl acetate fraction at 200 ppm level on palm oil and lard were similar to that of BHT at 200 ppm level, and better than BHA, ${\delta}-tocopherol$ and control.

  • PDF

Processing Flaxseed for Food and Feed Uses

  • Wiesenborn, Dennis;Tostenson, Kristi;Kangas, Nancy;Zheng, Yun-Ling;Hall III, Clifford;Niehaus, Mary;Jarvis, Paul;Schwarz, Jurgen;Twombly, Wesley
    • Food Science and Biotechnology
    • /
    • v.14 no.3
    • /
    • pp.305-310
    • /
    • 2005
  • Flaxseed is outstanding for lignans and oil rich in ${\alpha}$-linolenic acid which protect against several major illnesses. Better understanding of processing and storage characteristics of flaxseed will increase options for food use. Lignans and oil are found in the hull and embryo, respectively. Comparison of pearling and impact-dehulling processes for separation of lignan and oil-rich fractions showed the impact process was less effective, but easier to scale-up. Screw-pressing embryo reduced oil yield compared to whole seed, but doubled productivity and sharply reduced frictional heating of the oil. Flaxseed hull and embryo, also whole, ground and steamed-ground samples, were stable up to 30 weeks in closed containers at $23^{\circ}C$. Steamed-ground samples in open trays at $40^{\circ}C$ deteriorated markedly (peroxide value > 100 by 22 weeks); yet, whole seed remained stable. Incorporation of 18% flaxseed embryo into yellow perch feed increased ${\alpha}$-linolenic acid to 13 to l4% of muscle and liver lipids, compared to 0.5 to 0.7% in the no-embryo control. Feed conversion ratio, weight gain, and survival were similar. These studies are helping to establish the technological base for processing and utilizing flaxseed and flaxseed fractions to improve human diets.

Enhancement of Glucose-Fueled Cell-Free Protein Synthesis by the Addition of Lipids (지질의 첨가를 통한 포도당 기반 무세포 단백질 합성 시스템의 단백질 발현 효율 향상)

  • Lee, So Jeong;Kim, Ho-Cheol;Kim, Dong-Myung
    • Korean Chemical Engineering Research
    • /
    • v.57 no.1
    • /
    • pp.85-89
    • /
    • 2019
  • Cell-free protein synthesis utilizes the translational machinery in a cell extract. Unlike the conventional cell-based expression methods, not being affected by the conditions for cell growth, cell-free protein synthesis enables flexible manipulation of individual factors affecting the efficiency protein biosynthesis. However, the high cost and low stability of the energy sources to regenerate ATP have limited the use of cell-free synthesis for large-scale production of recombinant proteins. One of the approaches to address this problem is to use glucose as an alternative energy source to regenerate ATP through the glucose-metabolizing pathways in a cell extract. In this study, in an attempt to improve the efficiency of ATP regeneration by reinforcing oxidative phosphorylation process, we supplemented with cellular lipids to a glucose-fueled reaction mixture for cell-free protein synthesis. As a result of the lipid supplementation, the productivity of chloramphenicol acetyltransferase in a cell-free synthesis system using glucose increased more than 6 fold compared to when the lipid was not supplemented.

Inhibition of lipid and protein oxidation in raw ground pork by Terminalia arjuna fruit extract during refrigerated storage

  • Chauhan, Pranav;Pradhan, Soubhagya Ranjan;Das, Annada;Nanda, Pramod Kumar;Bandyopadhyay, Samiran;Das, Arun K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.2
    • /
    • pp.265-273
    • /
    • 2019
  • Objective: Terminalia arjuna plant, specially its leaves, bark, and roots, are widely used in traditional herbal medicine due to presence of bioactive components and being a rich source of natural antioxidants. But its fruit has not been used for any such purposes despite its potential to retard oxidation. Hence, the antioxidant potential of Arjuna fruit extract (AFE) in retarding lipid and protein oxidation of raw ground pork was evaluated during refrigerated storage for 9 days. Methods: The AFEs were prepared using different solvents viz. ethanol (EH), water, ethanol: water (60:40) and methanol:hot water (60:40). The AFEs were analysed for total phenolic content (TPC), 2, 2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power. Water extract (WE) and ethanol-water extract (EH-WE) were selected and incorporated at 1.0% into freshly minced pork meat and compared with a synthetic antioxidant, in retarding lipid and protein oxidation during storage. Results: The TPC in AFEs using different solvents ranged from 11.04 to 16.53 mg gallic acid equivalents/g and extracts exhibited appreciable scavenging activity ranging from 50.02% to 58.62%. Arjuna extracts significantly (p<0.05) improved the colour score of meat samples by reducing the formation of metmyoglobin during storage. Both the AFEs (WE and EH-WE) significantly (p<0.05) lowered the thiobarbituric acid reactive substances value, peroxide formation and formation of protein carbonyls in raw pork than control sample during storage. Upon sensory evaluation of all samples, it was found that AFE treatment could prolong the storage period of meat samples, without influencing the colour and odour score, up to 6 days. Conclusion: AFEs used at 1% improved the oxidative stability, colour and odour score and prolonged the refrigerated shelf life of ground pork up 6 days. Therefore, AFE could be explored as an alternative natural antioxidant in retarding lipid and protein oxidation in meat products.

Evaluation of Chemical-Nutritional Characteristics of Whey and Ricotta Obtained by Ewes Fed Red Grape Pomace Dietary Supplementation

  • Bennato, Francesca;Ianni, Andrea;Grotta, Lisa;Martino, Giuseppe
    • Food Science of Animal Resources
    • /
    • v.42 no.3
    • /
    • pp.504-516
    • /
    • 2022
  • This study aimed to investigate the effect on the chemical quality of whey and Ricotta obtained from ewes fed a red grape pomace (GP) dietary supplementation. The analyses were performed on whey, before and post Ricotta cheese-making, and in Ricotta after 1 (T1) and 5 (T5) d of ripening at 4℃. Moreover, fatty acid profile of whey before ricotta (WBR) cheese-making and Ricotta T1 of ripening and volatile profile of Ricotta T1 and T5 were investigated. The diet did not affect whey and Ricotta lipid content, conversely, significant variations were instead observed with regard to color. A lower amount of total phenolic compounds was found in WBR cheese-making, on the contrary, an opposite trend was highlighted in Ricotta T1 although no variations in antioxidant properties were detected. Moreover, GP modified fatty acid profile of whey and Ricotta but did not have any effect on protein profile of the main whey protein. The reduction of hexanal in Ricotta during the ripening suggest a better oxidative stability. The obtained results therefore suggested that the GP inclusion in the ewes diet, while modifying some chemical parameters, did not induce negative effects on the characteristics and quality of dairy by-products.