ABSTRACT
This study aimed to evaluate the influence of films based on chitosan and rosemary extract on the physicochemical, microbiological, and oxidative characteristics of beef. Refrigerated steaks of Longissimus dorsi were distributed in a factorial arrangement (4 × 4) into four treatments consisting of four edible films (control; chitosan; chitosan + 4% rosemary extract; and chitosan + 8% rosemary extract) and four days of aging (0, 2, 4, and 8 days). Incorporating 4% or 8% rosemary extract into the chitosan film improved the characteristics of the films in terms of moisture absorption and elasticity. The edible coatings with chitosan and rosemary extract and the different days of aging increased the tenderness and decreased the lipid oxidation of beef. In addition, the chitosan films containing rosemary extract increased the water-holding capacity and decreased the cooking losses of beef. The films containing 4% and 8% rosemary extract decreased the development of mesophilic and psychrotrophic bacteria and Staphylococcus ssp. in beef. We recommend incorporating 4% rosemary extract into chitosan-based coatings to preserve the quality of refrigerated beef.
ABSTRACT
O perfil metabólico é utilizado como monitoramento rotineiro para o diagnóstico de transtornos metabólicos, deficiências nutricionais e como preventivo de transtornos subclínicos, além da pesquisa de problemas de saúde e de desempenho de um rebanho. Neste contexto, o objetivo do presente trabalho foi avaliar a influência de diferentes dietas líquidas contendo soro de queijo e colostro sobre os perfis dos metabólitos séricos de bezerros durante a fase de aleitamento. Foram utilizados 24 bezerros mestiços provenientes de rebanhos leiteiros da região, distribuídos em delineamento inteiramente casualizado com três tratamentos e oito repetições: LI = Leite integral (controle); LS = 50% Leite integral + 50% de Soro de queijo in natura; SC = 70% de Soro de queijo in natura + 30% Colostro. Semanalmente foram coletadas amostras de sangue por punção jugular externa, no período da manhã, antes do fornecimento da dieta líquida e duas horas após a ingestão desta. As concentrações dos parâmetros séricos avaliados diferiram entre os tratamentos, porém sem comprometer o desempenho dos animais. Desse modo, a utilização de soro de queijo associado ao colostro apresenta-se como forma viável de redução de custos com aleitamento de bezerros, visto que possíveis déficits causados pelas diferenças nutricionais das dietas líquidas são supridos pelos alimentos sólidos, não afetando os perfis dos metabólitos séricos relacionados ao status protéico e energético.(AU)
Metabolic profile is used as routine monitoring for the diagnosis of metabolic disorders, nutritional deficiencies, and as a preventive of subclinical disorders, in addition to research health issues and performance of a herd. In this context, the aim of this study was to evaluate the influence of different liquid diets containing whey cheese and colostrum on the serum biochemistry profile of calves. Twenty-four crossbred calves from dairy herds in the region, distributed in a completely randomized design with three treatments and eight replicates: LI = Whole milk (control); LS = 50% Whole milk + 50% cheese whey in nature; SC = 70% of cheese whey in natura + 30% Colostrum. Weekly blood samples by jugular puncture were collected in the morning, before the supply of liquid diet and two hours after eating this. The serum concentrations of the evaluated parameters differ between treatments, but without compromising animal performance. Thus, the use of whey associated with colostrum presents itself as a viable cost reduction with feeding calves, since possible nutritional deficits caused by differences in liquid diets are supplied by solid food form, not affecting the profiles of the metabolites related to serum protein and energy status.(AU)
