Genetic characterization of Gift tilapia generations using microsatellite markers

The objective of this work was to characterize the genetic variability in parental (G0) and three subsequent generations (G1, G2 and G3) of genetically improved farmed tilapia (Gift) using microsatellite markers. Three hundred sixty individuals from the breeding program of Universidade Estadual de Maringá, PR, Brazil, were selected for weight gain. A total of 21 alleles was found in all five polymorphic microsatellite loci (G12292, UNH140; G12311, UNH159; G12312, UNH160; G12314, UNH162; and G12315, UNH163), with an average number between three and five alleles per locus. Allele frequencies ranged from 0.017 (UNH160 – G2) to 0.750 (UNH160 – G0). The average observed heterozygosity was 0.501, 0.391, 0.531, and 0.503 for G0, G1, G2 and G3, respectively. The average inbreeding coefficient was 0.192 (G0), 0.401 (G1), 0.230 (G2), and 0.301 (G3). All generations showed deviation from Hardy‑Weinberg equilibrium, with linkage disequilibrium in most loci. Except for G1, the heterozygosity was maintained in the G2 and G3 generations, which indicates that there is no significant loss of genetic variability in the breeding program

PROCESSING YELD AND PROXIMATE COMPOSITION OF Rhamdia voulezi FILLETS

The aim of this study was evaluate the effect of slaughter weight and sex on processing yield and on the proximate composition of Rhamdia voulezi. We calculated the percentage yield of the whole fish (carcass, clean trunk, abdominal muscle, fillet, edible parts, head, skin, gonads and visceral fat yield). There was no statistical difference in yields among weight classes (P>0.05). However, when assessing the income between sexes we observed significant difference (P0.05) among the classes, however, moisture, lipids and calories had significant difference (P<0.05) among the classes, and humidity decreased with increasing size of the fish, and lipid content and calorific value were higher for fish weighing 301-400 g. We oncluded R. voulezi with mass between 100 and 400 g presents equal yield processing, and fish weighing 301-400 g have higher lipid content in the fillet

Elaboração de biscoitos tipo <em>cookies</em> com inclusão de peixe

Objetivando desenvolver e caracterizar biscoitos tipo cookies com inclusão de peixe de duas espécies (Piaractus mesopotamicus e Oreochromis niloticus), foram elaboradas duas receitas padrão, com inclusão de 20% de carne mecanicamente separada de pacu, e outra com 20% de filé de tilápia. Realizaram-se análises microbiológicas, de umidade, proteínas, lipídeos, cinzas, fibra bruta, carboidratos e valor calórico dos cookies. Cinquenta julgadores avaliaram o perfil sensorial dos cookies (aparência, aroma, sabor, textura, crocância, impressão global), atitude em relação à compra e frequência de consumo. No perfil microbiológico, pode-se observar contagem inferior a 0,3 NMP/g para coliformes a 45ºC, ausência de Salmonella e contagem inferior a 10 UFC/g para Estafilococcus coagulase positiva. Na composição centesimal dos cookies, foi verificado menor valor (P0,05) para as duas formulações. Ambos os cookies tiveram alta aceitação, com notas superiores a 7,54 para todos os atributos avaliados. Porém, os cookies com tilápia apresentaram melhores notas, com escore superior (P<0,05) para o teste de consumo, compra, sabor, crocância e impressão global. Conclui-se que a carne mecanicamente separada de pacu e o filé de tilápia podem ser utilizados como matéria-prima para a elaboração de biscoitos tipo cookies, resultando em boa composição centesimal e qualidade microbiológica. No entanto, os cookies com inclusão de tilápia apresentaram melhores características sensoriais em relação aos cookies de pacu, indicando ótima aceitação do produto

<b>Nutritional, microbiological and sensorial characteristics of alfajor prepared with dehydrated mixture of salmon and tilapia

Current assay deals with the preparation of alfajores with different levels (0 to 15%) of dehydrated fish mixture of salmon (10%) and tilapia (90%) to assess the sensorial characteristics and their centesimal composition and microbiological. Fish inclusion in alfajores did not affect the aroma, taste, texture, color and physical aspect, with scores ranging between 6.70 and 7.96 of a hedonic scale of 9 score. An average score of 4 in a 5-score purchasing intention scale was obtained, or rather, tasters would probably buy the product. In the case of centesimal composition, inclusion affected (p 0.05) in lipids and calorie rates in the alfajores. Results show that the inclusion of up to 15% of a dehydrated mixture of salmon (10%) and tilapia (90%) in alfajores was greatly accepted and improved their nutrition values. Further, the product was also within the microbiological standards required by Brazilian sanitary laws

Imbalance of the redox system and quality of tilapia fillets subjected to pre-slaughter stress.

The objective of this study was to evaluate the effect of oxidative stress on the instrumental and sensory quality of Nile tilapia fillets. The experiment was conducted in a 2x2 factorial arrangement, evaluating densities (60 and 300 kg m-3) and depuration times (1 and 24 hours) in a total of four treatments. The serum levels of cortisol and gene expression levels of catalase (CAT), glutathione peroxidase (GPx) and 70 kDa heat shock protein (HSP70) as well as the pH, color, tenderness, water-holding capacity and sensory analysis of the fillets were evaluated. High density (300 kg m-3) resulted in higher mean cortisol levels, lower expression of CAT and GPx enzymes as well as higher expression of HSP70. Fish under this treatment also exhibited fillets with greater tenderness, higher lightness, lower redness and lower sensory acceptance. The longer depuration time (24 hours) resulted in lower expression of the CAT and GPx enzymes and fillets with higher lightness. The water-holding capacity was not affected by the different treatments. Therefore, low density and longer depuration times are recommended for decreased stress and improved quality of fillets

Several techniques for the preparation of flour from carcasses of the Pantanal alligator (Caiman crocodilus yacare)

AbstractFlour prepared via current assay methodologies from the carcasses of the Pantanal alligator (Caiman crocodilus yacare) was analyzed for its chemical composition, minerals, fatty acids, and sensorial profile. Carcasses of the Pantanal alligator, originating from the Coocrijapan scientific zoo, Cáceres MT Brazil, were utilized. The carcasses were cooked for 60 minutes in a pressure cooker with water containing 2% salt and 5% chimichurri. The cooked carcasses were then ground and the mass was used for the manufacture of flour via three techniques: non-smoked, hot-smoked, and liquid-smoked. After each technique, the carcasses were dehydrated at 60ºC for 3h and were ground. Alligator flour was then produced. The moisture of liquid-smoked flour (10.97%) was higher than that of non-smoked flour (3.78%) and hot-smoked flour (4.43%). The flours provided high protein (57.11% - 58.27%) and ash (23.45 &#8211; 26.42%) rates, and were predominantly calcium (6.77% - 7.69%), phosphorus (3.67% - 4.05%), and iron (73.13 &#8211; 273.73 ppm/100 mg). Smoked-flour had a better acceptance rate by tasters when compared to non-smoked flour. Results show that flours produced from alligator carcasses had high protein, ash, and mineral rates and a reasonable acceptability by most tasters