RESUMO
The influence of different ultraviolet (UV-C) doses (0.103 and 0.305 J/cm2 ) was investigated by instrumental color parameters, pH, lipid, and protein oxidations, fatty acids (FA) composition and biogenic amines (BAs) in Nile tilapia fillets during 11 d at 4 ± 1 °C. The UV-C treatment increased (P < 0.05) a* values and protein oxidation in a dose-dependent manner, and delayed (P < 0.05) the formation of BAs over the course of the storage period. L* values and lipid oxidation were not influenced (P > 0.05) by UV-C light. Fillets treated with a low UV-C dose exhibited greater (P < 0.05) total polyunsaturated fatty acid (PUFA) than their untreated counterparts. Therefore, a low UV-C dose can be recommended in tilapia fillets as an alternative processing method to control pH and BAs, as well as improve the total PUFA amount and overall nutritional quality.
Assuntos
Ácidos Graxos/análise , Estresse Oxidativo/efeitos da radiação , Alimentos Marinhos/efeitos da radiação , Raios Ultravioleta , Animais , Aminas Biogênicas/análise , Ciclídeos , Cor , Relação Dose-Resposta à Radiação , Irradiação de Alimentos , Concentração de Íons de Hidrogênio , Metabolismo dos LipídeosRESUMO
Physicochemical parameters of pasta enriched with tilapia (Oreochromis niloticus) flour were investigated. Five formulations were prepared with different concentrations of tilapia flour as partial substitute of wheat flour: pasta without tilapia flour (PTF0%), pasta with 6% (PTF6%), 12% (PTF12%), 17% (PTF17%), and 23% (PTF23%) of tilapia flour. The formulations were assessed for proximate composition, fatty acid and amino acid profile on day 1 whereas, instrumental color parameters (L*, a* and b* values), pH, water activity (aw), and lipid and protein oxidation were evaluated on days 1, 7, 14, and 21 of storage at 25°C. Fortification with tilapia flour increased (p < 0.05) protein, lipid, ash, total essential amino acids, and total polyunsaturated fatty acids contents. In addition, supplementation of pasta with tilapia flour decreased (p < 0.05) lightness and water activity while redness, yellowness, pH values, and lipid oxidation were increased (p < 0.05) in a level-dependent manner. Nevertheless, all formulations were exhibited storage stability at 25°C. In general, protein oxidation was greater (p < 0.05) in the pasta containing 12%, 17%, and 23% of tilapia flour than their counterparts, and the storage promoted an increase (p < 0.05) on the carbonyl content in all formulations. Thus, pasta with 6% of tilapia flour has the potential to be a technological alternative to food industry for the nutritional enrichment of traditional pasta with negligible negative effects on the chemical stability of the final product during 21 days at 25°C.
Assuntos
Farinha/análise , Alimentos Fortificados/análise , Valor Nutritivo , Tilápia , Aminoácidos/química , Animais , Cor , Culinária , Suplementos Nutricionais , Ácidos Graxos/química , Manipulação de Alimentos , Concentração de Íons de Hidrogênio , Lipídeos/química , Oxigênio/química , Proteínas/química , Temperatura , Triticum/químicaRESUMO
The influence of muscle source on color stability of fresh beef from purebred Bos indicus cattle was investigated. Longissimus lumborum (LL) and psoas major (PM) muscles obtained from twelve (n=12) Nellore bull carcasses (24h post-mortem) were fabricated into 2.54-cm steaks, aerobically packaged, and stored at 4°C for nine days. Steaks were analyzed on day 0 for proximate composition and myoglobin concentration, whereas pH, instrumental color, metmyoglobin reducing activity (MRA), lipid oxidation, and protein oxidation were evaluated on days 0, 3, 6, and 9. LL steaks exhibited greater (P<0.05) redness, color stability, and MRA than PM counterparts. On the other hand, PM steaks demonstrated greater (P<0.05) myoglobin content, lipid oxidation, and protein oxidation than LL steaks. These results indicated the critical influence of muscle source on discoloration of fresh beef from Bos indicus animals and suggested the necessity to engineer muscle-specific strategies to improve color stability and marketability of beef from Bos indicus cattle.
Assuntos
Músculo Esquelético/química , Estresse Oxidativo , Carne Vermelha , Animais , Bovinos , Cor , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Metabolismo dos Lipídeos , Masculino , Metamioglobina/análise , Proteínas Musculares/química , Mioglobina/análise , Refrigeração , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
Dietary ractopamine improves pork leanness, whereas its effect on sarcoplasmic proteome has not been characterized. Therefore, the influence of ractopamine on sarcoplasmic proteome of post-mortem pork Longissimus thoracis muscle was examined. Longissimus thoracis samples were collected from carcasses (24 h post-mortem) of purebred Berkshire barrows (n=9) managed in mixed-sex pens and fed finishing diets containing ractopamine (RAC; 7.4 mg/kg for 14 days followed by 10.0 mg/kg for 14 days) or without ractopamine for 28 days (CON). Sarcoplasmic proteome was analyzed using two-dimensional electrophoresis and mass spectrometry. Nine protein spots were differentially abundant between RAC and CON groups. Glyceraldehyde-3-phosphate dehydrogenase and phosphoglucomutase-1 were over-abundant in CON, whereas serum albumin, carbonic anhydrase 3, L-lactate dehydrogenase A chain, fructose-bisphosphate aldolase A, and myosin light chain 1/3 were over-abundant in RAC. These results suggest that ractopamine influences the abundance of enzymes involved in glycolytic metabolism, and the differential abundance of glycolytic enzymes could potentially influence the conversion of muscle to meat.
Assuntos
Agonistas Adrenérgicos beta/farmacologia , Glicólise/efeitos dos fármacos , Proteínas Musculares/metabolismo , Músculos Paraespinais/metabolismo , Fenetilaminas/farmacologia , Proteoma/metabolismo , Carne Vermelha/análise , Animais , Peso Corporal/efeitos dos fármacos , Cruzamento , Dieta , Substâncias de Crescimento/farmacologia , Humanos , Masculino , Cadeias Leves de Miosina/metabolismo , Músculos Paraespinais/enzimologia , Mudanças Depois da Morte , SuínosRESUMO
The aim of this study was to evaluate physical and sensory characteristics of low-sodium tilapia steaks restructured with microbial transglutaminase. Polyphosphate (0.4%), condiment mixes-onion powder and garlic powder (2.5%), water (10.0%), transglutaminase (1.0%), and different types of salts (1.5%) were mixed with non-commercial sized fillets. Substitution of NaCl by KCl or MgCl2 (at 50% each) affected quality attributes and decreased (P < 0.05) consumer acceptability. The tri-salt steaks (KCl, MgCl2, and NaCl at 1:1:2 ratio) improved some attributes and increased (P < 0.05) acceptability and purchase intention. We conclude that potassium and magnesium chlorides are possible replacers of salt (NaCl) in restructured tilapia steaks and potentially decrease the risk factor for heart failure associated with high sodium consumption.