Sensory,microbiological and chemical assessment of the freshness of red mullet (Mullus barbatus) and goldband goatfish (Upeneus moluccensis) during storage in ice

The shelf life of red mullet and goldband goatfish during ice storage were studied in terms of sensory, microbiological and chemical changes. The sensory acceptability limit was 8 days for goldband goatfish (Upeneus moluccensis) and 11 days for red mullet (Mullus barbatus) stored in ice. The TVC level was correlated with sensory assessment. The TVC exceeded 7 log cfu g⁻¹ after 8 days for goldband goatfish, and 11 days for red mullet. At the end of storage period, pH, TVB-N, TBA, FFA and PV for red mullet were 7.84, 47.19 mg/100 g, 0.69 mg MA kg⁻¹, 1.17% oleic acid and 1.58 meq O₂/kg and for goldband goatfish they were 7.53, 43.97 mg/100 g, 0.74 mg MA kg⁻¹, 1.62% oleic acid and 1.68 meq O₂/kg, respectively. In red mullet, agmatine, serotonin, histamine and dopamine became the dominant amines, reaching 7.30, 5.97, 2.52 and 2.31 mg/100 g, respectively. Also the dominant amines for goldband goatfish were 4.37, 3.88, 3.38 and 2.00 mg/100 g for histamine, agmatine, dopamine and putrescine, respectively.     

OXIDATIVE DEHYDROGENATION OF ETHANE OVER A MONOLITH COATED BY MOLYBDENUM-VANADIUM-NIOBIUM MIXED-OXIDE CATALYST

Oxidative dehydrogenation of ethane to ethylene was investigated using Mo 0.71 V 0.21 Nb 0.08 mixed-oxide catalyst, in powder form and coated over a monolith. At 570°C and with a feed stream containing an O 2 /C 2 H 6 mole ratio of one, ethylene selectivity value reaching to 96% was obtained at a conversion level of about 5% with the monolith-supported catalyst. DRIFTS studies indicated the presence of adsorbed ethoxide species. The proposed reaction scheme for the production of ethylene includes the elimination of β-hydrogen of adsorbed species by the lattice oxygen.     

Effect of the type of frying oil on volatile compounds of goatfish (Upeneus pori) during cold storage

The effect of different types of oil (sunflower, soybean, corn and canola oil) on the volatile formation of fried goatfish (Upeneus pori) during refrigerated (2 °C) storage period were assessed in this study. When using the SPME technique, forty‐three compounds were detected. Among the detected compounds twelve aldehydes, nine alcohols, nine acids, three ketones, four amines and seven other compounds were found in raw and fried goatfish during refrigerated storage periods. Frying with different types of oil had significant influence on the volatile compounds of goatfish. However, considerable differences observed in the formation of some volatile compounds depending on type of frying oil. It was also concluded that, changes in volatile compounds during cold storage periods were not good spoilages markers for fried goatfish.     

Inactivation of Listeria monocytogenes and Listeria innocua in yogurt drink applying combination of high pressure processing and mint essential oils

Influences of high pressure processing (HPP) on some physical properties and on inactivation of Listeria monocytogenes and Listeria innocua in a yogurt drink (ayran) were quantified with or without addition of mint essential oil. Pressure treatment alone or combined with mint essential oil did not cause significant changes in pH, water activity, color and serum protein separation (p > 0.05). HPP of ayran samples at 600 MPa for treatment time of 300 s reduced L. monocytogenes and L. innocua by more than 5-log units (p ≤ 0.05) at ambient temperature. Addition of mint essential oil further enhanced inactivation of both bacteria by more than 1 log cfu mL^?1. Combination of mint essential oil with HPP provided a reduction in pressure treatment severity by 100–300 MPa or by 210 s to achieve the same amount of inactivation relative to HPP alone. Both Weibull distribution and log-logistic models were fitted to survival data. High pressure-processing combined with mint essential oil appeared to be a promising technique for preserving microbiologically-safe ayran with no significant impacts to product quality.     

Amino acid and fatty acid composition of wild sea bass (Dicentrarchus labrax): a seasonal differentiation

Seasonal variations in the amino acid and fatty acid compositions of wild sea bass (Dicentrarchus labrax) captured in the north eastern Mediterranean were investigated. In all seasons, the major amino acids in sea bass fillets were determined to be aspartic acid, glutamic acid and lysine. Methionine, tyrosine and histidine composition of the fillets were lower than those of the other amino acids in all seasons. The ratios of essential (E, g amino acid/16 g N)/nonessential (NE, g amino acid/16 g N) amino acids were observed to be 0.75 for winter, 0.76 for autumn, 0.77 for both spring and summer. Results showed that, sea bass fillets are well-balanced food source in terms of E/NE ratios in all seasons. In addition, seasonal differences in polyunsaturated fatty acid (PUFA) composition of the fillets were observed in all seasons. The major fatty acids of sea bass fillets were observed to be palmitic acid (16:0), oleic acid (18:1ω9), eicosapentaenoic acid (EPA, 20:5ω3) and docosahexaenoic acid (DHA, 22:6ω3). The amounts of EPA+DHA in autumn, winter, spring and summer were determined as 0.16, 0.12, 1.14 and 1.02 g/100 g wet weight, respectively.     

Anatomical and histological studies of the alimentary canal of adult maize leaf weevil,Tanymecusdilaticollis Gyllenhal, 1834 (Coleoptera: Curculionidae)

In this study, ananatomical and histological study was conducted on the alimentary canal of Tanymecusdilaticollis (Coleoptera: Curculionidae), which is an economic polyphagous pest species, to study the relationship between the structure of the alimentary canal and the feeding habit. Therefore, the structure of the alimentary canal of T. dilaticollis was examined using light and electron microscopies. Results have shown that the alimentary canal in T. dilaticollis is consisted of three separate regions as foregut, midgut, and hindgut structurally between the mouth and the anus, which pass from head, thorax, and abdomen. The foregut consists of pharynx, esophagus, crop and proventriculus and in the crop part, expansion is seen compared to other foregut parts. Midgut of T. dilaticollis is the largest part of digestion system. The anterior region of midgut is twofolds wider than the posterior region. The posterior midgut extends tubularly and it is connected to eightgastric caeca. The hindgut of T. dilaticollis consists of fourparts as pylorus, ileum, colon, and rectum. Well‐developed muscle layers are found near the rectum and genital chamber. These results contribute to further studies on the ecology and biological control agents of Coleoptera and to provide a broad comparison of alimentary canal of Coleoptera species.     

Trade openness and regional income spillovers in Brazil: A spatial econometric approach*

This paper employs a spatial Durbin growth model to estimate the impact of trade openness on regional per capita income in Brazil using a data set of 469 Brazilian micro‐regions over the period 2004–2007. We calculate the direct, indirect and cumulative impact on per capita income of trade openness and human capital in these micro‐regions. Results indicate that greater trade openness in a region promotes economic development locally, while exerting negative influence on per capita income of the neighbouring regions. Our findings also show that human capital has a positive – direct and indirect – impact on the economic development of Brazilian micro‐regions.