Teófilo José Pimentel da Silva

Differential abundance of sarcoplasmic proteome explains animal effect on beef Longissimus lumborum color stability

The sarcoplasmic proteome of beef Longissimus lumborum demonstrating animal-to-animal variation in color stability was examined to correlate proteome profile with color. Longissimus lumborum (36 h post-mortem) muscles were obtained from 73 beef carcasses, aged for 13 days, and fabricated to 2.5-cm steaks. One steak was allotted to retail display, and another was immediately vacuum packaged and frozen at -80°C. Aerobically packaged steaks were stored under display, and color was evaluated on days 0 and 11. The steaks were ranked based on redness and color stability on day 11, and ten color-stable and ten color-labile carcasses were identified. Sarcoplasmic proteome of frozen steaks from the selected carcasses was analyzed. Nine proteins were differentially abundant in color-stable and color-labile steaks. Three glycolytic enzymes (phosphoglucomutase-1, glyceraldehyde-3-phosphate dehydrogenase, and pyruvate kinase M2) were over-abundant in color-stable steaks and positively correlated (P<0.05) to redness and color stability. These results indicated that animal variations in proteome contribute to differences in beef color.

Physico-chemical and sensory attributes of low-sodium restructured caiman steaks containing microbial transglutaminase and salt replacers

Our objective was to examine the physico-chemical and sensory attributes of low-sodium restructured caiman steaks containing microbial transglutaminase (MTG) and salt replacers (KCl and MgCl2). Trimmings from caiman carcasses were processed into restructured steaks with or without MTG and salt replacers; the five treatments were CON (1.5% NaCl), T-1 (1.5% NaCl+1% MTG), T-2 (0.75% NaCl+1% MTG+0.75% KCl), T-3 (0.75% NaCl+1% MTG+0.75% MgCl2), and T-4 (0.75% NaCl+1% MTG+0.375% KCl+0.375% MgCl2). T-4 demonstrated the greatest (P<0.05) succulence and the lowest (P<0.05) values for cooked hardness, springiness, and cohesiveness. The greatest (P<0.05) purchase intention was for T-3. Furthermore, T-3 and T-4 were similar (P>0.05) to controls in salty flavor. Our findings suggest that the combination of MTG, KCl, and MgCl2 can be employed as a suitable salt reduction strategy in restructured caiman steaks without compromising sensory attributes and consumer acceptance.

Classificação do mel em floral ou mel de melato

Honey is a natural product made by bees using flowers nectar (floral honey) or excretion of alive parts of plants or either excretion produced by sucking insects from alive parts of plants (honeydew honey). Honeydew is an alternative food source used by bees. In Santa Catarina state, honeydew honey is produced from january to april, each two years. In order to identify the presence of honeydew honey, 25 samples were sampled randomly from january/93 to june/96. They were colected from different apiaries in different periods of time and tested for moisture, pH, ash, reducing sugars, and the results were used in the application of Kirkwood equation to classify honey as floral or honeydew. They were analised for polarimetry, to classify them according to Kirkwood and White. The statistical study was done by the application of exact test of Fisher and, in spite of some divergences found to classify 4 samples, the statistical study showed correlation between Kirkwood and White methods, indicating that both can be used.

Color attributes and oxidative stability of longissimus lumborum and psoas major muscles from Nellore bulls

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.

Effects of transport time and rest period on the quality of electrically stimulated male cattle carcasses.

Forty-five castrated Nelore-breed male cattle, with average age of 37 months, were randomly chosen. The cattle were submitted to the combination of two transport times (up to 2h and approximately 5h) and five rest periods (0h, 6h, 12h, 18h and 24h). The carcasses were electrically stimulated. After 24h postmortem, the average of the ultimate pH in the M. Longissimus dorsi (LD) was considered normal (5.57-5.72) for eight out of nine cattle groups. The shear force (SF) was higher for cattle that were not allowed a rest period (0h) on both transport times, however it was not significant (p>0.05). This result was compatible with the sarcomere length (SL), which were shorter for those carcasses. The rest period and transport time had no influence on the L(∗) (lightness) values, but a(∗) (redness) values increased until the 12th hour of rest. The b(∗) (yellowness) value was negative for the cattle without a rest period (0h) and transported for 5h. The cattle transported for up to 2h could be allowed a 6-h rest period only, and the cattle transported for 5h could be allowed a 12-h rest period without the meat quality being affected significantly.

Sex-specific effect of ractopamine on quality attributes of pork frankfurters.

Our objective was to determine the effect of dietary ractopamine and immunocastration on the quality attributes of pork frankfurters. Gilts (GT), surgically castrated male pigs (SR) and immunologically castrated male pigs (IM) were fed diets containing 7.5 ppm ractopamine (RAC) or no ractopamine (CON) for 21 days prior to harvest. Deboned hams were manufactured into frankfurters, and physico-chemical parameters, instrumental color and texture, and sensory attributes were evaluated. Ractopamine increased (P<0.05) L* (lightness) in SR, whereas it decreased (P<0.05) lightness in IM and GT. While ractopamine increased (P<0.05) a* (redness) in GT, a reverse (P<0.05) trend was observed in SR. With respect to instrumental texture, ractopamine increased (P<0.05) hardness, resistance, and springiness in IM, cohesiveness and springiness in GT, and shear force in SR. These results indicated that ractopamine exerted sex-specific effects on frankfurter quality. Swine industry may adopt sex-specific dietary strategies to optimize the quality of further processed meat products.

Lactato de sódio, nisina e sua combinação na validade comercial da linguiça Toscana embalada a vácuo e estocada a 4°C

The aim of this study was to evaluate the shelf life of four commercial formulations pork sausage (Control - no added additive, F1 - added 3% sodium lactate, F2 - added 0.5% nisin and F3 - added 3 % sodium lactate and 0.5% nisin). The samples were distributed into polyethylene bags containing 200 grams for each day of storage and formulation for subsequent bacteriological and physicochemical analysis. All formulations were vacuum packed and stored at 4°C. Regarding the shelf life samples were submitted to the following bacteriological counts of heterotrophic bacteria aerobic mesophilic and psychrotrophic; count of lactic acid bacteria count and Enterobacteriaceae. The analyzes were carried out physico-chemical: pH, water activity and the content of thiobarbituric acid reactive substance. Interpreting the results obtained in the experiment it was concluded that the use of a combination of 3% sodium lactate and 0.5% nisin increased the shelf life compared to other samples. Key words: natural antimicrobial, bacteriocin, storage and pork sausage filling.

Caracterização do processo de rigor mortis do músculo Ilio-ischiocaudalis de jacaré-do-pantanal (Caiman crocodilus yacare) e maciez da carne

This paper studied six pantanal alligators (Caiman crocodilus yacare) carcass with goal of rigor mortis process characterization of Ilio-ischiocaudalis muscle during industrial cooling and meat tenderness. The alligators were randomly assembled and slaughtered at Cooperativa de Criadores do Jacare do Pantanal (COOCRIJAPAN) - Caceres- Mato Grosso After exsanguination, were mensured temperature of chilling room and carcasses, pH and samples were collected for determination the sarcomere length, shear force and cooking loss at different times (0.5, 3, 5, 7, 10, 12, 15, 24 and 36 hours). The temperature of chilling room varied from 2.6°C (0.5h) to 0.9°C (36h) and the mean carcass temperature from 21.0°C to 4.2°C, respectively. The mean initial pH of the muscle was 6.7 and the final was 5.6. The smallest sarcomere size ocurred at 15 hours after exsanguination (1.5µm). This meat presents shear force lower than 6.0kg.

Ocorrência de resíduos de dietilestilbestrol e zeranol em fígado de bovinos abatidos no Brasil

O uso de substâncias anabolizantes, de natureza hormonal ou nao, e muito difundida na pecuaria de corte dos paises maiores produtores de carne bovina (EUA, Australia, Argentina, Canada, etc.). Dentre estas destacam-se o banido dietilestilbestrol (DES) e o controlado zeranol, que aumentam o ganho de peso vivo, o peso da carcaca, a eficiencia alimentar e o percentual de carne. O uso porem, pode ocasionar a presenca de residuos nos tecidos e orgaos dos animais que sao utilizados como alimento. A presenca de residuos representa um perigo potencial para a saude humana, o que levou varios paises, inclusive o Brasil, a proibirem a utilizacao destes produtos. O objetivo do presente trabalho foi o de verificar, se a carne colhida no periodo de julho de 1993 a novembro de 1994, em matadouros frigorificos pertencentes a Lista Geral dos Exportadores, atende a legislacao vigente quanto ao uso destes anabolizantes. Para isto, foram analisadas por radioimunoensaio, 416 amostras de figado para pesquisa de DES e 385 para zeranol. Observou-se que o DES nao foi detectado em nenhuma das amostras (p > 0,05), enquanto que o zeranol foi detectado em duas (p < 0,05). A presenca do zeranol nestas amostras foi confirmada por cromatografia gasosa acoplada a espectrometria de massa (p < 0,05). A recuperacao media obtida na fase extrativa (3H-DES) foi de 62,6 ± 5,7% , enquanto que na fase extrativa + radioimunoensaio (DES), esta recuperacao foi de 83,8 ± 16,8%. Quanto ao zeranol as recuperacoes medias obtidas foram de 63,0 ± 5,8% na fase extrativa (3H-zeranol) e 94,8 ± 13,8% na fase extrativa + radioimunoensaio (zeranol). Concluiu-se portanto, que a carne bovina brasileira atende a legislacao vigente quanto a ausencia de residuos de DES, no entanto, contraria quanto ao zeranol, pois foi confirmada uma frequencia de 0,52% de amostras positivas.

Impact of UV‐C Light on the Fatty Acid Profile and Oxidative Stability of Nile Tilapia (Oreochromis niloticus) Fillets

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.