Effect of processing (cutter versus continuous emulsifier) and sodium reduction on the physicochemical properties of bologna sausages.

BACKGROUND: Overcoming the impact of sodium reduction in the properties of emulsified sausages is a current challenge in the production of healthier meat products. Because the emulsifying process play a key role in the stability of sausages, the present study aimed to evaluate the effects of two mechanical emulsifying systems (cutter versus continuous emulsifier) and two levels of sodium chloride (2.50 and 1.25%) on the physicochemical characteristics of bologna sausages. RESULTS: A reduction of sodium increased the L* value and reduced the a* value, and also decreased the protein extraction yield in sausages produced in the cutter system. Moreover, the emulsion stability of reduced sodium batter was increased by cutter emulsification (F50C). On the other hand, the continuous emulsifier process did not decrease the extraction of myofibrillar proteins in F50E (sodium reduced treatment), resulting in minimal impact on emulsion stability and an increase in hardness in reduced-sodium sausages. CONCLUSION: Therefore, to produce low-sodium sausages, the continuous emulsifier was more effective producing batters with increased extracted myofibrillar proteins, improving the structure and functionality of myofibrillar proteins compared to the cutter process. © 2023 Society of Chemical Industry.

Comparison of physicochemical and volatile flavor properties of neon flying squid (Ommastrephes bartramii), jumbo squid (Dosidicus gigas), and Argentine shortfin squid (Illex argentinus) during chilled storage.

The difference and similarities in the physicochemical and volatile flavor properties were determined in neon flying squid (OB), jumbo squid (DG), and Argentine squid (IA) mantles during 8 days of chilled storage. Physicochemical analysis indicated the chilled conditions induced rapid increases in pH value, total volatile basic nitrogen (TVBN), and carbonyl and malondialdehyde (MDA) content of the three squid species. In addition, myofibrillar protein (MP) content decreased and springiness in the OB, DG, and IA mantle samples declined with the extension of storage time. Importantly, OB mantles presented less chemical stability than the other two squid samples during 8 days of chilled storage. In addition, histological observations suggest DG mantle tissues presented more compact structures than those of the other two samples. Volatile flavor analysis showed propionaldehyde, 3-pentanone, trimethylamine, 3-furanmethanol, 2-methyl butyric acid, and 2-butanone were highly abundant in the squid mantles after storage, likely resulting from decomposition, oxidation, and degradation of proteins and lipids in the squid mantle, which varied with different squid species. The findings provide insight into the performance of three squid species during chilled storage.

Residues of Fluoroquinolone Antibiotics Induce Carbonylation and Reduce In Vitro Digestion of Sarcoplasmic and Myofibrillar Beef Proteins.

Although the impact of oxidation on human health has been of growing interest, the oxidation of proteins, major component of meat, has received little attention. This paper describes the in vitro effect of five fluoroquinolones (FQs) on carbonylation of sarcoplasmic and myofibrillar proteins of beef when found at concentrations close to the maximum residue limit (MRL). Samples were treated individually with the FQs, determining in each protein fraction the carbonyl index, protein content and oxidized proteins identification, using 2,4-dinitrophenyhydrazine (DNPH) alkaline assay, Western blot and Bradford methods, and mass spectrometry, respectively. Besides, the in vitro effect of these residues on gastric and duodenal digestion of proteins was evaluated. The carbonylation induced by FQs affected both protein fractions being significant with respect to the blank in 73.3% of cases. This damage was correlated with loss of solubility and digestibility, with sarcoplasmic proteins the most affected. Danofloxacin and enrofloxacin were the FQs with greatest oxidant effects, especially affecting glycolysis and glycogen proteins. Our results suggest that these residues induce irreversible oxidative damage on the main beef proteins and could affect their nutritional value.

Comparison of different methods for determining the extent of myofibrillar fragmentation of chilled and frozen/thawed beef across postmortem aging periods.

To evaluate different methods for the determination of postmortem myofibrillar fragmentation, three protocols were compared: fragmentation index method (FI) after drying the filtrate residue at room temperature for 10 min (FIroom) or at 105 °C for 12 h (FIoven); and myofibrillar fragmentation index (MFI) by the absorbance method. Beef Longissimus thoracis steaks (n = 34) were randomized into two treatments (frozen/thawed and unfrozen) and aged for 0, 7, 14 or 21 days. An interaction (P < 0.05) between method and treatment, method and aging and treatment and aging was found. FIroom was the best to detect a difference in fragmentation at all aging days. In addition, FIroom and FIoven both detected the tenderization process that occurs by freezing while the MFI method did not, yet all three methods were similarly related to tenderness as measured by shear force. It is suggested that FIroom is the most effective method (time, cost) to indicate myofibrillar fragmentation, under the conditions imposed herein.

Emulsified films produced with proteins extracted from whitemouth croaker byproducts: development and characterization / Filmes emulsionados produzidos com proteínas extraídas de subprodutos de corvina: desenvolvimento e caracterização

This study aimed to develop and characterize biodegradable films from myofibrillar proteins from whitemouth croaker (Micropogonias furnieri) using stearic acid (SA) to improve its technological properties. The proteins extracted were lyophilized, characterized, and used to prepare the films. The filmogenic solutions were dried on a silicone stand at 35 °C for 14 h in an incubator oven according to the casting method. The region with the best mechanical, physical, and barrier properties in the films was defined by a full factorial design. The lyophilized myofibrillar proteins (LMP) had protein content of 96.03%. The analysis of the experimental design results indicated the best conditions to prepare the optimized film were 2.84% LMP, 3.18% SA, and 78.41% SDS (sodium dodecyl sulfate). The control films were prepared with 2.84% LMP and 30% plasticizer. The optimized film had significantly lower water vapor permeability (5.87E-11 g m m-2 s-1 Pa-1), higher tensile strength (6.35 MPa), and lower elongation (235.60%) compared with control (p≤0.05). It also had lower transparency values and excellent UV barrier property, which indicates a tendency to opaque. Thermal stability was good and the microstructure revealed a structural change in the filmogenic matrix, confirmed by x-ray diffraction, which indicates influence of SDS and SA on film crystallinity. Solubility increased by 22% and swelling decreased slightly in the optimized film compared to the control. The results obtained represent a positive contribution with the use of fish byproducts by applying alternative, sustainable technologies.(AU)

O objetivo deste trabalho foi desenvolver e caracterizar filmes biodegradáveis de proteínas miofibrilares de aparas da filetagem da corvina (Micropogonias furnieri) utilizando ácido esteárico (AE) para melhorar suas propriedades tecnológicas. As proteínas extraídas foram liofilizadas, caracterizadas e utilizadas na elaboração dos filmes. As soluções filmogênicas foram secas em suporte de silicone a 35°C por 14 horas em estufa incubadora, de acordo com o método casting. A região com as melhores propriedades mecânicas, físicas e de barreira dos filmes foi definida por planejamento fatorial completo. As proteínas miofibrilares liofilizadas (PML) apresentaram teor proteico de 96,03%. A análise dos resultados do planejamento experimental indicou que as melhores condições para elaborar o filme otimizado foram: 2,84% PML, 3,18% AE e 78,41% SDS (dodecil sulfato de sódio). Os filmes controles foram elaborados com 2,84% de PML e 30% de plastificante. O filme otimizado apresentou significativa diminuição da permeabilidade ao vapor de água (5,87E-11 g m m-2 s-1 Pa-1), com maior resistência a tração (6,35 MPa) e menor elongação (235,60%) quando comparado ao controle (p ≤ 0,05. Apresentando também menores valores de transparência e excelente propriedade de barreira UV, indicando tendência ao opaco. Apresentou boa estabilidade térmica e a microestrutura revelou mudança estrutural na matriz filmogênica, confirmado pela difração de raio-x, indicando a influência do SDS e AE na cristalinidade do filme. Houve aumento de 22% na solubilidade e ligeira diminuição do intumescimento do filme otimizado em relação ao controle. Os resultados obtidos representam contribuição positiva com o aproveitamento de subprodutos de peixe aplicando tecnologias alternativas e sustentáveis.(AU)

Emulsified films produced with proteins extracted from whitemouth croaker byproducts: development and characterization / Filmes emulsionados produzidos com proteínas extraídas de subprodutos de corvina: desenvolvimento e caracterização

This study aimed to develop and characterize biodegradable films from myofibrillar proteins from whitemouth croaker (Micropogonias furnieri) using stearic acid (SA) to improve its technological properties. The proteins extracted were lyophilized, characterized, and used to prepare the films. The filmogenic solutions were dried on a silicone stand at 35 °C for 14 h in an incubator oven according to the casting method. The region with the best mechanical, physical, and barrier properties in the films was defined by a full factorial design. The lyophilized myofibrillar proteins (LMP) had protein content of 96.03%. The analysis of the experimental design results indicated the best conditions to prepare the optimized film were 2.84% LMP, 3.18% SA, and 78.41% SDS (sodium dodecyl sulfate). The control films were prepared with 2.84% LMP and 30% plasticizer. The optimized film had significantly lower water vapor permeability (5.87E-11 g m m-2 s-1 Pa-1), higher tensile strength (6.35 MPa), and lower elongation (235.60%) compared with control (p≤0.05). It also had lower transparency values and excellent UV barrier property, which indicates a tendency to opaque. Thermal stability was good and the microstructure revealed a structural change in the filmogenic matrix, confirmed by x-ray diffraction, which indicates influence of SDS and SA on film crystallinity. Solubility increased by 22% and swelling decreased slightly in the optimized film compared to the control. The results obtained represent a positive contribution with the use of fish byproducts by applying alternative, sustainable technologies.

O objetivo deste trabalho foi desenvolver e caracterizar filmes biodegradáveis de proteínas miofibrilares de aparas da filetagem da corvina (Micropogonias furnieri) utilizando ácido esteárico (AE) para melhorar suas propriedades tecnológicas. As proteínas extraídas foram liofilizadas, caracterizadas e utilizadas na elaboração dos filmes. As soluções filmogênicas foram secas em suporte de silicone a 35°C por 14 horas em estufa incubadora, de acordo com o método casting. A região com as melhores propriedades mecânicas, físicas e de barreira dos filmes foi definida por planejamento fatorial completo. As proteínas miofibrilares liofilizadas (PML) apresentaram teor proteico de 96,03%. A análise dos resultados do planejamento experimental indicou que as melhores condições para elaborar o filme otimizado foram: 2,84% PML, 3,18% AE e 78,41% SDS (dodecil sulfato de sódio). Os filmes controles foram elaborados com 2,84% de PML e 30% de plastificante. O filme otimizado apresentou significativa diminuição da permeabilidade ao vapor de água (5,87E-11 g m m-2 s-1 Pa-1), com maior resistência a tração (6,35 MPa) e menor elongação (235,60%) quando comparado ao controle (p ≤ 0,05. Apresentando também menores valores de transparência e excelente propriedade de barreira UV, indicando tendência ao opaco. Apresentou boa estabilidade térmica e a microestrutura revelou mudança estrutural na matriz filmogênica, confirmado pela difração de raio-x, indicando a influência do SDS e AE na cristalinidade do filme. Houve aumento de 22% na solubilidade e ligeira diminuição do intumescimento do filme otimizado em relação ao controle. Os resultados obtidos representam contribuição positiva com o aproveitamento de subprodutos de peixe aplicando tecnologias alternativas e sustentáveis.