Fatty acid composition of tench by Bahar Tokur
International Journal of Food Science and Technology, Jul 1, 2007
Wild sea bass (Dicentrarchus labrax) captured from north eastern Mediterranean in autumn and wint... more Wild sea bass (Dicentrarchus labrax) captured from north eastern Mediterranean in autumn and winter were stored at )18 °C, and their chemical and sensory quality were investigated for up to 9 months. At the end of autumn storage period, pH, total volatile basic nitrogen, thiobarbituric acid values, free and bound formaldehyde, free formaldehyde and protein solubility were 6.69, 15.59 mg 100 g )1 , 0.086 mg MA kg )1 , 1.23 mg kg )1 , 3.58 mg kg )1 and 15.72 g 100 g )1 , respectively. The same parameters for winter storage were 6.55, 12.08 mg 100 g )1 , 0.308 mg MA kg )1 , 3.38 mg kg )1 , 4.95 mg kg )1 and 14.39 g 100 g )1 , respectively. None of the chemical quality parameters exceeded the acceptability limits. These results were supported by the results of sensory analyses (colour, odour, flavour, texture and overall acceptability). It was also concluded that differences in initial proximate composition and chemical quality scores of wild sea bass captured in autumn and winter did not have an effect on the chemical and sensory quality during frozen storage.
International Journal of Food Science and Technology, Jul 1, 2007
In this study, the effects of frying, oven-baking, barbecuing, and smoking on the proximate compo... more In this study, the effects of frying, oven-baking, barbecuing, and smoking on the proximate composition and lipid quality of trout (Onchorhynchus mykiss) were studied. The proximate compositions were affected significantly by all cooking methods. An increase in the lipid content and a decrease in the moisture content were observed in all the cooking methods. A decrease in the protein content was found in barbecued and smoked samples, but not in fried or oven-baked, on dry-weight basis. Regarding the lipid quality, the free fatty acids (FFA, grams of oleic acid per 100-g lipid), peroxide values (POV, meq active oxygen per kg lipid), and thiobarbituric acid values (TBA, mg malonaldehydeper kg fish muscle) were analysed. The FFA contents in fresh, fried, oven-baked, barbecued and smoked trout on wet-weight basis were found to be 8.76, 0.76, 5.05, 0.81, and 9.44-g oleic acid per 100-g lipid, respectively. POV in fried, oven-baked, and barbecued samples increased significantly, while POV in smoked samples decreased significantly. An increase was observed in the TBA value in trout cooked with all methods. The results of this experiment showed that heating accelerates lipid oxidation.
DergiPark (Istanbul University), Sep 1, 2006
) boyunca kalitesindeki değişimler. Sebze püresi ile kaplanmış alabalık filetoları (TFVT)' nın be... more ) boyunca kalitesindeki değişimler. Sebze püresi ile kaplanmış alabalık filetoları (TFVT)' nın besinsel, kimyasal ve duyusal kalitesi üzerine -18 o C' de dondurarak depolamanın etkisi belirlenmeye çalışılmıştır. Ayrıca kontrol grubu olarak sebze püresi ile kaplanmamış alabalık filetosu (TF)' da değerlendirilmiştir. Depolama sonucunda, TFVT' de methionin ve TF' de histidin amino asidi hariç diğer tüm amino asitler yavaşça azalmıştır. Tiyobarbiturik asit (TBA) değeri (mg malonaldehit/kg) taze iken 0.20 mg malonaldeyhit/kg iken, depolama sonucunda SPAF' de 0.50 mg malonaldeyhit/kg' a TF' de ise 1.30 mg malonaldeyhit/kg' a önemli bir şekilde artmıştır (p<0.05). Toplam uçucu bazik azot (TVB-N) değerinde (mg N/100 g) TFVT' de önemli bir değişim görülmemiştir (p>0.05). TF' de ise, TVB-N değeri (p<0.05) depolamanın 5. ayında önemli bir şekilde artmış, daha sonra yavaşça azalmış ve sabit kalmıştır. Myofibriller ve sarkoplazmik protein çözünürlüğü her iki grupta da önemli bir şekilde azalmıştır (p<0.05). Duyusal değerlendirmede; renk koku, tat, doku yapısı ve genel kabul edilebilirlik TFVT' de önemli bir değişim göstermezken tüm bu parametrelerin skorları TF' de azalmıştır. Buna rağmen ne TFVT' de ne de TF' de depolama boyunca panelistler tarafından verilen skorlar kabul edilemez sınırına ulaşmamıştır.
The effects of the prooxidants and antioxidants on the lipit oxidation in fish
Balıkların kas dokularında bulunan en önemli prooksidanlar yapısında hem olan ve olmayan pigmentl... more Balıkların kas dokularında bulunan en önemli prooksidanlar yapısında hem olan ve olmayan pigmentler, Fe (kompleks), ferritin, mitokondri-sarkoplazmik retikulum enzim sistemi, NADH (nikotinamid adeniıı dinüleotid hidrojenaz) ve lipoksijenaz'dır. Antioksidanlar ise suda çözünen SOD (süperoksit dismutaz), katalaz, Fe-tutucular, askorbat, GSH (glutatyon) peroksidaz, GSH ile yağda çözünen tokoferoller, ubiquinol ve karotenoyitler'dir. Özellikle çok doymamış yağ asitleri (PUFA), proteinler,-DNA ve bazı renk pigmentleri, prooksidanlarm etkisi altındadır. Balıkların dokularında bulunan veya işleme aşamasında ürünlere katılan antioksidanlar, bu etkileşimin derecesini düşürerek, ürünlerin raf ömrünün uzamasına ve kalitenin artmasına yardımcı olurlar. Bu derleme makalesinde, balıklarda lipit oksidasyonunu etkilemede önemli bazı prooksidan ve antioksidanlarm etki mekanizmaları incelenmiştir.The most important prooxidants in fish muscle are heme and non-heme pigments, Fe (complex), ferri...
Physical, chemical and sensory evaluation of sardines (Sardina pilchardus (Walbaum, 1792)) stored at no-frost conditions
Ege Journal of Fisheries and Aquatic Sciences, 2003
Bu araştırmada, taze ve temizlenmiş olarak, sardalya balıklarının (Sardina pilchardus (Walbaum, 1... more Bu araştırmada, taze ve temizlenmiş olarak, sardalya balıklarının (Sardina pilchardus (Walbaum, 1792)) 140 gün ile no-frost koşullarında depolanması sonucunda meydana gelen fiziksel, kimyasal ve duyusal kalite değişikleri incelenmiştir. Donmuş balık eti kalitesini belirleyen fiziksel kriter olarak pH, balıkların enzimatik, biyokimyasal ve mikrobiyolik bozulmalarını belirleyen kimyasal kriterler olarak tiyobarbitürik asit (TBA) mg malonaldehit/ kg örnek, toplam uçucu temel azot (TVB-N) mg N/100 gr örnek ve formaldehit (FA) değerleri ve duyusal kriterler olarak da renk, koku, lezzet, genel kabul edilebilirlik ve doku yapısında meydana gelen değişmeler belirlenmiştir. Depolama boyunca ortalama pH, TBA, TVB-N, FA(ex) ve FA(dest) değerleri sırası ile, 6,41-6,53,0,50-4,76 mg malonaldehit/kg örnek, 16,8-21,0 mg N/100 gr örnek, 1,74-2,39 mg FA/kg, 1,55-4,125 mg FA/kg olarak saptanmıştır. Araştırmanın sonucunda, fiziksel ve kimyasal kalite kriterlerinin tüketilebilirlik sınırını aşmadığı ancak, kalite değerlendirilmesinde, duyusal analizler sonucu elde edilen bulguların, fiziksel ve kimyasal analiz bulgularından daha hızlı ilerlediği sonucuna varılmıştır.In this study, sensory, chemical, and physical analyses were carried out on sardines (Sardina pilchardus) as fresh and cleaned, during 140 days of storage at no-frost conditions. pH as physical criteria which determine quality of frozen fish meat, thiobarbyturic acid (TBA) mg malonaldehyde/ kg sample, total volatile base nitrogen mg N/100 gr sample and formaldehyde (FA) as criteria which determine enzymatic, biochemical and microbiology deterioration of fish and also sensory criteria as color, odour, taste, consumption value and texture firm were considered. During storage, the means of pH, TBA, TVB-N, free FA|ex) and free and bound FA^eit) values were 6.41-6.53, 0.50-4.76 mg malonaldehyde/kg sample, 16.8-21.0 mg N/100 gr sample, 1.74-2.39 mg FA(ex)/kg and 0.66- 1.55 mg FA(dest)/kg, respectively. At the end of this study, the critical value of chemical and physical quality criteria were not reached. However, the values of results obtained in sensory analyses were rapidly improved than value of physical and-chemical analyses in the evaluation of quality
Balıklarda lipit oksidasyonunu belirlemek için iki tiyobarbiturik asit (TBA) metotunun karşılaştırılması
Ege Journal of Fisheries and Aquatic Sciences, 2006
Changes in the quality of fishburger produced
The quality of wild common sole (Solea solea) stored in ice was investigated by chemical (K value... more The quality of wild common sole (Solea solea) stored in ice was investigated by chemical (K value, biogenic amines, protein degradation (SDS and SDS-PAGE), pH, peroxide value (PV), free fatty acids (FFA), total volatile basic nitrogen (TVB-N), tiobarbituric acid (TBA) analyses), sensory (raw and cooked fish) and microbiological methods. The quality of common sole decreased on day 16 (fair quality-B) and they were no longer acceptable on day 20 (unacceptable quality-C). When common sole were considered as fair quality (B) by assessors on ~16-18 days, the average K value was ≥ 80%. Among the investigated biogenic amines, histamine was not detected. No major change in the protein profiles of common sole was observed. Sensory, microbial and biochemical results revealed that the shelf life of common sole was approximately ~16-18 days. Among the chemical parameters, the most consistent indicator to measure the change in freshness was K value that showed linear response with storage time.
The effects of Fenton type (Fe+2/H2O2) oxidation system on lipid and protein oxidation of grey mullet (Mugil cephalus)
Journal of Fisheries Sciences.com, 2007
Oxidative damages of lipid and protein in grey mullet (Mugil cephalus) were investigated in vitro... more Oxidative damages of lipid and protein in grey mullet (Mugil cephalus) were investigated in vitro by using Fenton reactants (Fe+2SO4/H2O2) to generate hydroxyl radical formation. Thiobarbutiric acid-reactive substances (TBARs, mg maonladehyde/ kg) were used to determine free radical- mediated oxidation of lipids. The oxidative modification of proteins was confirmed by carbonyl formation using with 2,4-dinitrophenylhydrazine (DNPH) and DNPH labeled of
Journal of Fisheries Sciences.com, 2008
Bu çalışmada, donmuş alabalık (Oncorhynchus mykiss) ve sardalya (Sardina pilchardus)' ın protein ... more Bu çalışmada, donmuş alabalık (Oncorhynchus mykiss) ve sardalya (Sardina pilchardus)' ın protein kalitesine, mikrodalgada, akan su altında ve oda sıcaklığında çözündürmenin etkileri araştırılmıştır. Balıkların protein kalitesinde meydana gelen değişimi belirlemek için myofibriller protein miktarı, protein çözünürlüğü ve sodyum dodesil sülfat poli-akrilamid jel elektroforezi (SDS-PAGE) analizleri yapılmıştır. Alabalık ve sardalyada dondurma ve çözündürme işlemi myofibriller proteinlerin miktarında azalmaya neden olmuştur (p<0.05). Genel olarak dondurma ve çözündürme işlemi her iki balık türü için protein çözünürlüğünde önemli bir azalmaya neden olurken (p<0.05), farklı çözündürme işlemlerinin protein çözünürlüğüne olan etkisi balık türlerine göre değişmiştir. Her iki balık türü için en yüksek protein çözünürlüğü akan su altında çözündürülme ile sağlanmıştır (p<0.05). SDS-PAGE analizi sonucunda ise farklı çözündürme metotlarının disülfit kovalent bağlarla protein denatürasyonuna neden olmadığı bulunmuştur. Elde edilen veriler, proteinlerin non-disülfit kovalent bağlarla veya protein-lipit gibi diğer bileşiklerle olan interaksiyonunun protein çözünürlüğünün azalmasının nedeni olabileceğini göstermektedir.
The Effect of Different Types of Fibers on Protein Quality of Crab Leg Analog Paste and Gel Made from Alaska Pollock ( Theragra chalcogramma )
Journal of Aquatic Food Product Technology, 2012
The aim of this investigation was to evaluate the effect of wheat, citrus, and carrot fiber on pr... more The aim of this investigation was to evaluate the effect of wheat, citrus, and carrot fiber on protein oxidation and denaturation of crab leg analog pastes and gels produced from Alaska pollock surimi. There were no significant differences between protein carbonyl contents of the crab leg analog pastes with and without dietary fibers (DF; p &amp;amp;gt; 0.05). The extractability of
International Journal of Food Science & Technology, 2007
SummaryWild sea bass (Dicentrarchus labrax) captured from north eastern Mediterranean in autumn a... more SummaryWild sea bass (Dicentrarchus labrax) captured from north eastern Mediterranean in autumn and winter were stored at −18 °C, and their chemical and sensory quality were investigated for up to 9 months. At the end of autumn storage period, pH, total volatile basic nitrogen, thiobarbituric acid values, free and bound formaldehyde, free formaldehyde and protein solubility were 6.69, 15.59 mg 100 g−1, 0.086 mg MA kg−1, 1.23 mg kg−1, 3.58 mg kg−1 and 15.72 g 100 g−1, respectively. The same parameters for winter storage were 6.55, 12.08 mg 100 g−1, 0.308 mg MA kg−1, 3.38 mg kg−1, 4.95 mg kg−1 and 14.39 g 100 g−1, respectively. None of the chemical quality parameters exceeded the acceptability limits. These results were supported by the results of sensory analyses (colour, odour, flavour, texture and overall acceptability). It was also concluded that differences in initial proximate composition and chemical quality scores of wild sea bass captured in autumn and winter did not have an ...
International Journal of Food Science & Technology, 2007
In this study, the effects of frying, oven-baking, barbecuing, and smoking on the proximate compo... more In this study, the effects of frying, oven-baking, barbecuing, and smoking on the proximate composition and lipid quality of trout (Onchorhynchus mykiss) were studied. The proximate compositions were affected significantly by all cooking methods. An increase in the lipid content and a decrease in the moisture content were observed in all the cooking methods. A decrease in the protein content was found in barbecued and smoked samples, but not in fried or oven-baked, on dry-weight basis. Regarding the lipid quality, the free fatty acids (FFA, grams of oleic acid per 100-g lipid), peroxide values (POV, meq active oxygen per kg lipid), and thiobarbituric acid values (TBA, mg malonaldehydeper kg fish muscle) were analysed. The FFA contents in fresh, fried, oven-baked, barbecued and smoked trout on wet-weight basis were found to be 8.76, 0.76, 5.05, 0.81, and 9.44-g oleic acid per 100-g lipid, respectively. POV in fried, oven-baked, and barbecued samples increased significantly, while POV in smoked samples decreased significantly. An increase was observed in the TBA value in trout cooked with all methods. The results of this experiment showed that heating accelerates lipid oxidation.
Nutritional composition of frog (Rana esculanta) waste meal
Bioresource Technology, 2008
In the present study, the waste obtained from the frozen frog leg industry was used for the produ... more In the present study, the waste obtained from the frozen frog leg industry was used for the production of frog waste meal, and its proximate, amino acids, fatty acids, mineral and vitamin compositions were evaluated to determine the nutritional quality. In addition, the total bacterial count, Salmonella, total volatile basic nitrogen (TVB-N, mgN/100g) and thiobarbituric acid (TBA, mg malonaldehyde/kg) were also measured to determine the microbiological and chemical quality of frog waste meal (FWM). The crude protein, fat and ash content of FWM on a dry weight basis were 68.6%, 17.0% and 13.2%, respectively. The amino acid profiles were found to be fairly close to those of fish meal in terms of protein sources and rich in the glutamic acid, glycine, proline, arginine, and methionine. The proportions of fatty acid composition in FWM were analysed and findings were 26.7% for total saturated fatty acid (SFA), 42.5% for total monounsaturated fatty acid (MUFA), 17.0% for total n - 6 and 3.3% for n - 3 ratio. The major SFA, MUFA and PUFA in FWM were palmitic acid (19.1%), oleic acid (26.0%) and linoleic acid (16.7%), respectively. FWM was found to be high in mineral content, especially Zn, K, Cu, Mn, and Mg and high level of some vitamins such as folic acids and thiamin. The total bacterial count was found to be 2.9x10(4) CFU/g, and Salmonella was not observed. TVB-N and TBA in FWM was determined to be 157.4+/-5.8 mg N/100g and 1.2+/-0.1 mg malonaldehyde/kg, respectively.
Ege Journal of Fisheries and Aquatic Sciences, Sep 1, 2006
) boyunca kalitesindeki değişimler. Sebze püresi ile kaplanmış alabalık filetoları (TFVT)' nın be... more ) boyunca kalitesindeki değişimler. Sebze püresi ile kaplanmış alabalık filetoları (TFVT)' nın besinsel, kimyasal ve duyusal kalitesi üzerine -18 o C' de dondurarak depolamanın etkisi belirlenmeye çalışılmıştır. Ayrıca kontrol grubu olarak sebze püresi ile kaplanmamış alabalık filetosu (TF)' da değerlendirilmiştir. Depolama sonucunda, TFVT' de methionin ve TF' de histidin amino asidi hariç diğer tüm amino asitler yavaşça azalmıştır. Tiyobarbiturik asit (TBA) değeri (mg malonaldehit/kg) taze iken 0.20 mg malonaldeyhit/kg iken, depolama sonucunda SPAF' de 0.50 mg malonaldeyhit/kg' a TF' de ise 1.30 mg malonaldeyhit/kg' a önemli bir şekilde artmıştır (p<0.05). Toplam uçucu bazik azot (TVB-N) değerinde (mg N/100 g) TFVT' de önemli bir değişim görülmemiştir (p>0.05). TF' de ise, TVB-N değeri (p<0.05) depolamanın 5. ayında önemli bir şekilde artmış, daha sonra yavaşça azalmış ve sabit kalmıştır. Myofibriller ve sarkoplazmik protein çözünürlüğü her iki grupta da önemli bir şekilde azalmıştır (p<0.05). Duyusal değerlendirmede; renk koku, tat, doku yapısı ve genel kabul edilebilirlik TFVT' de önemli bir değişim göstermezken tüm bu parametrelerin skorları TF' de azalmıştır. Buna rağmen ne TFVT' de ne de TF' de depolama boyunca panelistler tarafından verilen skorlar kabul edilemez sınırına ulaşmamıştır.
European Food Research and Technology, Apr 1, 2004
In this study, the chemical and sensory qualities of fishburger produced from tilapia (Oreochromi... more In this study, the chemical and sensory qualities of fishburger produced from tilapia (Oreochromis niloticus) were investigated during frozen storage (18 C) over 8 months. The ratios of crude protein, lipid, moisture, crude ash, and polyunsaturated fatty acids in tilapiaburger were found to be 17.82%, 5.29%, 66.68%, 2.56% and 7.95% respectively. At the end of the study, the total volatile basic nitrogen value was found to have fluctuated throughout the storage periods. The highest thiobarbituric acid value was found at the 7th month as 0.142 mg malonaldehyde/kg. The peroxide value was 0.18 meq/kg at the beginning of the storage but increased to 5.03 meq/kg at 6th month of storage and then decreased to 0.82 meq/kg at the 8th month. The level of free fatty acids was 2.73% oleic acid at the beginning but reached 4.14% in the first month of storage and then increased to 5.92% at the end of the storage. pH values ranged between 8.01 and 7.97. At the end of the storage period, sensory quality criteria were scored as quite near those of the fresh samples.
Comparison of Two Thiobarbituric Acid (TBA) Method for Monitoring Lipid Oxidation in Fish
Ege Journal of Fisheries and Aquatic Sciences, Sep 1, 2006
FATTY ACID COMPOSITION OF RED MULLET (<i>MULLUS BARBATUS</i>): A SEASONAL DIFFERENTIATION
Journal of Muscle Foods, 2009
ABSTRACT Seasonal variations in the fatty acid compositions of red mullet (Mullus barbatus) captu... more ABSTRACT Seasonal variations in the fatty acid compositions of red mullet (Mullus barbatus) captured from Iskenderun bay, northeastern Mediterranean, were investigated. In all sampling seasons, the major fatty acids of red mullet were palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), palmitoleic acid (16:1), eicosapentaenoic acid (EPA, 20:5ω3) and docosahexaenoic acid (DHA, 22:6ω3). The fatty acid contents of red mullet were influenced by seasonality. The levels of polyunsaturated fatty acid were 17.32% in autumn, 17.69% in winter and 20.13% in spring. The levels of DHA in the total fatty acids in autumn, winter and spring were 4.36, 8.25 and 10.89%, while those of EPA were 7.93, 4.59 and 4.56, respectively. The present study suggest that red mullet is a good source of ω3 series fatty acids, and the weekly consumption of 300 g of red mullet in autumn, winter or summer could meet EPA + DHA requirements of people.PRACTICAL APPLICATIONSRed mullet is one of the most commercially important fish species in many Mediterranean countries. Little information is available on the fatty acid composition of red mullet. Therefore, seasonal proximate analysis and the fatty acid composition of red mullet were determined and discussed in this paper. There is much interest in the beneficial effects on human health that is related to consumption of marine lipids. Determination of the effects of different fishing seasons on the fatty acid composition of red mullet will provide valuable information concerning the nutrient value of this seafood for both consumers and the researchers working on nutrient tables. In addition, this basic information will be obtained for the fish processing industry.
Food Chemistry, 2007
The effects of a hydroxyl radical-generating system induced by iron catalyzed oxidation (Fe 2+ /H... more The effects of a hydroxyl radical-generating system induced by iron catalyzed oxidation (Fe 2+ /H 2 O 2 ) on lipids and proteins of sardine, Atlantic bonito, anchovy and bluefish were investigated. Thiobarbituric acid-reactive substances (TBARs, mg malonaldehyde/kg fish muscle) formation was used to evaluate oxidative damage of the lipid in dark muscle fish due to iron catalyzed oxidation. The amount of TBARs was observed to increase significantly in sardine and anchovy as the incubation time increased, while Atlantic bonito and bluefish reached their maximum values of TBARs within the first 3 h of incubation, and after that did not change (p < 0.05). Carbonyl contents (nmol carbonyl/mg protein) of all fish samples measured as an index of protein oxidation were affected differently by the iron-catalyzed oxidation system during incubation. However, significant increases in the carbonyl groups were detected in sardine, Atlantic bonito and bluefish, but not in anchovy as a result of the long incubation time (5 h) (p < 0.05). When comparing to increases Atlantic bonito showed the maximum increase protein carbonyl. The electrophoretic patterns in the presence and absence of b-mercaptoethanol showed that a loss of proteins generally occurred in all fish at the end of incubation, and the greatest alteration in protein bands was observed in anchovy during Fe 2+ -catalyzed oxidation. The bands above 50 kDa disappeared within the first 1 h of incubation. The loss of protein (both high and low molecular weight) may involve disulfide and non-disulfide covalent linking during the iron catalyzed incubation. These data suggest that an increase in TBARs and fragmentation, and a loss of proteins exposed to iron-catalyzed oxidation may explain the oxidative damage of lipids and proteins which causes quality loss and limits the storage life of dark muscle fish.
The Effect of Whey Protein Isolate Coating Enriched with Thyme Essential Oils on Trout Quality at Refrigerated Storage (4 ± 2°C)
Journal of Aquatic Food Product Technology, 2016
ABSTRACT The present study evaluated the effect of whey protein isolate (WPI) coating enriched wi... more ABSTRACT The present study evaluated the effect of whey protein isolate (WPI) coating enriched with thyme essential oil (EO; 3, 5, and 7%, v/v) on whole trout chemical and microbial quality during refrigerated storage at 4 ± 2°C. As a result of this study, the addition of thyme essential oil to WPI coatings enhanced quality significantly better than that of the control and WPI coating without thyme essential oil during refrigerated storage, and this effect increased with an increase in the thyme EO concentration in WPI coating.
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Fatty acid composition of tench by Bahar Tokur