Chemical, bioactive properties and in vitro digestibility of spray-dried fish silages: Comparison of two discard fish (Equulites klunzingeri and Carassius gibelio) silages

The fermented fish silages produced with Streptococcus spp., Lactobacillus brevis, Lactobacillus plantarum, Pediococcus acidilactici and Enterococcus gallinarum, and formic acid silages were compared for production of two discard fish silages (Equulites klunzingeri and Carassius gibelio). The E/NE ratio of spray-dried fish silages was determined in range of 0.80–1.10 for E. klunzingeri and 0.80–0.90 for C. gibelio silages. Pediococcus acidilactici and En. gallinarum groups had greater antioxidant activity than other silage groups. The DPPH radical scavenging ability was found as 6.14%–14.71% and 6.99%–13.36% for E. klunzingeri and C. gibelio silages, respectively. The OMD, ME and NEL values were determined in range of 69.74%–80.08%, 6.38–8.65 MJ/kg DM and 6.45–7.49 MJ/kg DM, respectively for spray-dried E. klunzingeri silages and 81.18%–86.62%, 8.97–9.61 MJ/kg DM and 7.61–8.08 MJ/kg DM, respectively, for spray-dried C. gibelio silages. According to the nutritional and chemical evaluation, spray-dried fish silages have great potential as a feed components because of high rate of digestibility and nutritious components. © 2017 John Wiley & Sons LtdTürkiye Bilimsel ve Teknolojik Araştirma Kurumu: TOVAG-213O166This work was supported by the Cukurova University and The Scientific and Technological Research Council of Turkey (TOVAG-213O166)

Novel Approaches in Seafood Preservation Techniques

[No abstract available

Effects of cooking and reheating methods on the fatty acid profile of sea bream treated with rosemary extract

BACKGROUND: The effects of rosemary extract on the fatty acid profile of sea bream fillets cooked by different methods (oven baking, grilling and pan frying) as well as the effects of different reheating methods (microwave and conventional oven) on the fatty acid composition of fish after frozen storage for 4 months were investigated. Results: The proportion of saturated fatty acids increased only slightly in fried samples but significantly in oven-baked and grilled samples, while the proportion of polyunsaturated fatty acids (PUFAs) increased significantly in fried samples but only slightly in oven-baked and grilled samples. The proportion of monounsaturated fatty acids remained relatively constant after cooking. Of the fatty acids analysed, themost significant increases(P < 0.05) were observed in C18: 1n-9 and C18: 2n-6 and the most significant decreases (P < 0.05) in C14: 0, C16:1, C20: 5n-3 and C22: 6n-3. Although sea bream fillets fried in sunflower oil showed an increase in PUFAs, the lowest eicosapentaenoic and docosahexaenoic acid contents were found in fried samples. CONCLUSION: Sea bream fillets treated with rosemary extract showed slower oxidation than untreated fish. Neither conventional nor microwave reheating after frozen storage for 4 months had a detrimental effect on the fatty acid profile and its stability. © 2009 Society of Chemical Industry

Gamma-irradiation induced effects on biogenic amine formation and quality of frog legs (Rana esculenta) during storage

Chemical, microbiological and sensorial properties were investigated depending on the storage time to understand the impacts of gamma irradiation at doses of 4 and 5 kGy on frog legs (Rana esculenta) during storage at 2 °C. While TVB-N values of control groups found as 50.11 mg/100 g after a 10 day storage period, 4 and 5 kGy frog legs were found as 48.08 and 43.29 mg/100 g respectively after 17 days. TBA values for irradiated frog legs were observed to be higher at the end of their storage periods. Salmonella was totally eliminated by 4 kGy irradiation. A total of seven biogenic amines; putrescine, cadaverine, spermidine, spermine, histamine, serotonin and agmatine were recorded in frog legs. Ammonia, putrescine, cadaverine and agmatine contents of non-irradiated group were significantly increase during storage period. Other microbiological analysis showed that irradiation at 5 kGy was the best at eliminating bacteria. Consequently, the treatment of irradiation as a preservation method was found to prolong the shelf life of frog legs 7 days longer than the usual methods in cold storage. © 2018 Elsevier Lt

Comparison of fatty acid, mineral and proximate composition of body and legs of edible frog (Rana esculenta)

PubMedID: 19382332The fatty acid profile and mineral composition (calcium, magnesium, sodium, phosphorus, potassium, iron, zinc, manganese, silicon, boron, cadmium, chromium, nickel, aluminium, copper, and lead) by Inductively Coupled Plasma-Atomic Emission Spectometry (ICP-AES) and the proximate composition of the body and legs of edible frog (Rana esculenta) were investigated. The fatty acids occurring in the highest proportions in both the body and leg of frogs were mystiric acid (C14:0, 1.13-2.30%), palmitic acid (C16:0, 19.76-23.23%), stearic acid (C18:0, 3.61-6.29%), palmitoleic acid (C16:1, 7.06-13.08%), oleic acid (C18:1n-9 cis, 10.83-16.71%), linoleic acid (C18:2n-6, 6.44-6.71%), ?-linolenic (C18:3n-6, 0.13-0.27%), linolenic (C18:3n-3, 2.32-3.37%), cis-11,14,17-eicosatrienoic acid (C20:3n-3, 4.71-7.72%), cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n-3, 3.96-6.05%) and cis-4,7,10,13,16,19-docosahexaenoic acid (C22:6n-, 2.77-6.67%). Among the minerals determined, potassium was found to be highest, followed by phosphorus. Calcium, aluminium, cadmium, copper, lead, chromium, nickel, boron, silicon and zinc are found to be lower than the potential toxicity levels

The capability of rosemary extract in preventing oxidation of fish lipid

The effects of rosemary extract at different levels (%1, R1, and %2, R2) on the quality of vacuum-packed sardine in terms of sensory, biochemical (thiobarbituric acid, total volatile basic nitrogen, peroxide value and free fatty acids) and microbiological analyses (total viable counts) were investigated. Fish were filleted and divided into three groups. First group was used as the control (C) without rosemary extract, second group was treated with 1% rosemary extracts (10 g L-1) for 2 min (R1), and the third was treated with 2% rosemary extracts (20 g L-1) for 2 min (R2). Thirty fillets per litre were used. After that, all groups were vacuum-packed in polyethylene bags. The samples were stored in the refrigerator condition (4 ± 1 °C) over the storage period of 20 days. The results showed that the use of rosemary extract improved the sensory quality of both raw and cooked sardine, most preferably sardine treated with 1% of rosemary. Biochemical analysis showed that the use of 2% of rosemary extract were found to be most effective (P &lt; 0.05) in controlling the rate of lipid oxidation. © 2010 The Authors. Journal compilation © 2010 Institute of Food Science and Technology

Bioconversion of Discard Fish (Equulites klunzingeri and Carassius gibelio) Fermented with Natural Lactic Acid Bacteria; the Chemical and Microbiological Quality of Ensilage

Valorisation of discard fish and fish wastes fermented with lactic acid bacteria have potential biotechnological application to produce high quality animal food. Five lactic acid bacteria strains naturally present in fish (Lactobacillus brevis, Lactobacillus plantarum, Pediococcus acidilactici, Streptococcus spp. and Enterococcus gallinarum) and formic acid were evaluated for the production of fish silages made from two discard fish species [Equulites klunzingeri (Klunzinger’s pony fish-marine fish) and Carassius gibelio (Gibel carp—freshwater fish)]. Chemical (pH, TBA and non-protein nitrogen analyses) and microbiological (total aerobic and anaerobic microorganism counts, lactic acid bacteria, fungi, total coliform and pathogen bacteria) aspects were investigated during maturation process in silages groups. Gibel silages ripened in a short time (in 3 days) than silages prepared with Equulites klunzingeri (in 2 weeks). A slight increase in non-protein nitrogen value (0.4–0.7 g 100 g-1) was detected in all silage groups. TBARs values of formic acid groups were significantly higher than the fermented groups during the 3-week period. Fish silages prepared with Lactobacillus brevis and Streptococcus spp. had the highest lipid stability in all fermented groups according to TBA values. No pathogen bacteria were detected in all silage groups. According to the chemical and microbiological evaluations on silages, these lactic acid bacteria can be used successfully as starter cultures in order to produce high quality animal food from discard fish. © 2018, Springer Nature B.V

Effects of laurel and myrtle extracts on the sensory, chemical and microbiological properties of vacuum-packed and refrigerated European eel (Anguilla anguilla) fillets

Summary: The effects of extracted natural antioxidant (laurel and myrtle) on the sensory, chemical (TVB-N, TBARS, PV, FFA and pH) and microbiological (total viable count, psychrotrophic bacteria and Enterbacteriaceae counts) properties of vacuum-packaged European eel (Anguilla anguilla) stored at 4 ± 1 °C were investigated. The TBARS values of myrtle were significantly lower than that of other groups. The peroxide value was low for European eel treated with myrtle and laurel extract. The FFA-free fatty acid concentration increased from 0.44 (% oleic acid) (2.03) in the eel during 24 days of storage. The values of pH showed statistically significant (P < 0.05) changes for all groups. The myrtle significantly reduced bacterial growth in fillets (P < 0.05). The microbiological limit of 7 log cfu per gram did not exceed in the treated groups. Data showed that the extracts of myrtle and laurel contain substances that inhibit oxidation of lipids and growth of bacteria in European eel, indicating the potential value of these extracts to extend the shelf life of fish. © 2013 Institute of Food Science and Technology

Reactivity in 7-benzyl-2,7-naphthyridine derivatives: Nucleophilic substitutions, rearrangements, heterocyclizations and related reactions

Background and Objective: Continuing our studies in the field of a new rearrangement in the 2,7- naphthyridine series, the synthesis and rearrangement of mono- 2 and di-amino derivatives 3 of 2,7- naphthyridine was carried out. Taking into account the wide range of pharmacological activities of pyrazole derivatives the synthesis of some 3-amino-1-(3,5-dimethyl-1H-pyrazol-1-yl)-2,7-naphthyridines 8 and of pyrazolo[3,4-c]-2,7-naphthyridine 12 was described. Methods: Compounds 2 were reacted with amines furnishing the relevant rearrangement products 4. Starting from the 7-benzyl-3-chloro-1-hydrazino-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile 6 and 5-hydrazino- 6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c]-2,7-naphthyridin-1-amine 12 the 7-benzyl-3-chloro-1-(3,5-dimethyl-1Hpyrazol- 1-yl)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile 7 and 3,5-dimethyl-1H-pyrazol-1-yl-9,11- dimethylpyrimido[1',2':1,5]pyrazolo[3,4-c]-2,7-naphthyridine 13 were synthesized, via the Knorr synthesis of pyrazoles. Results: The syntheses of 2-benzyl-6,8-diamino-3,4-dihydro-2,7-naphthyridin-1(2H)ones 4 deriving from the rearrangement of compounds 2 and/or 3 were performed. By reaction with benzylamine compound 2a or 3g gave the unexpected formation of N,7-dibenzyl-8-(benzylimino)-3-pyrrolidin-1-yl-5,6,7,8-tetrahydro-2,7- naphthyridin-1-amine 5: in fact, the rearrangement was followed by condensation between the C-1 carbonyl group of the 2,7-naphthyridine ring and the benzylamine. Starting from the 7-benzyl-3-chloro-1-(3,5-dimethyl- 1H-pyrazol-1-yl)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile 7 the relevant 3-amino-7-benzyl-1-(3,5- dimethyl-1H-pyrazol-1-yl)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitriles 8 were obtained. In harsh experimental conditions the nucleophilic substitution of the 1-pyrazolyl residue took place with formation of 7- benzyl-1,3-bis[(2-hydroxypropyl)amino]-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile 10. Moreover compound 7 reacted with hydrazine hydrate giving the pyrazolo[3,4-c]-2,7-naphthyridine 12, which, in turn furnished a new tetra-heterocyclic system: 3-benzyl-5-(3,5-dimethyl-1H-pyrazol-1-yl)-9,11-dimethyl-1,2,3,4- tetrahydropyrimido[1',2': 1,5]pyrazolo[3,4-c]-2,7-naphthyridine 13. Conclusion: Replacement of methyl group on piperidine ring of 2,7-naphthyridine system with the benzyl one led to new results. Reaction of compound 2a or 3g with benzylamine brought to an unexpected formation of N,7-dibenzyl-8-(benzylimino)-3-pyrrolidin-1-yl-5,6,7,8-tetrahydro-2,7-naphthyridin-1-amine 5. The reactivity of 7-benzyl-3-chloro-1-(3,5-dimethyl-1H-pyrazol-1-yl)-2,7-naphthyridine 7 with nucleophiles was investigated observing the unexpected substitution of the 1-pyrazolyl residue