ABSTRACT
The aim of this study was to evaluate the antioxidant effect of dietary supplementation of plant oil resins in laying hens on the oxidative stability of cooked egg yolk kept at 4ºC for 30 days, and fresh eggs stored under refrigeration (R) at the same temperature for 60 days or kept in room temperature (RT) for 30 days. Hens were fed corn- and soybean-based diets (15% CP and 2,900 kcal kg-1) and supplemented with two levels of Copaifera langsdorffii oil resin (CP-0.03; 0.06 and 0.09%) or Pterodon emarginatus oil resin (SC-0.03 and 0.06%), plus a negative control (CN). At 37 weeks of age, 667 eggs were collected and randomly distributed in different storage conditions, in natura or cooked. The progression of lipid oxidation of egg yolk in natura was quantified in quadruplicate and cooked egg yolks in duplicate, using pool of 3 egg yolks/treatment to analyze TBARS (thiobarbituric acid reactive substances) concentration in quadruplicate. Data analysis was performed using a mixed model and Tukey test, at a 5% significance level. The storage period was considered a longitudinal factor, which varied from five times, for R cooked yolk and TA fresh yolk (0-30 days), to nine times, for R fresh yolk (0-60 days). For fresh eggs stored at RT or R, the supplementation of plant oils did not protect egg yolks from lipid oxidation, compared to NC. However, for cooked egg yolks, the addition of 0.03 and 0.06% of CP oil resin showed antioxidant activity since it reduced lipid oxidation up to day 21 of storage, but had a prooxidant effect for 0.09%. Therefore, it can be concluded that the supplementation of copaíba oil resin had an antioxidant protection of cooked egg lipids...
O objetivo deste trabalho foi avaliar a atividade antioxidante da adição de óleos de copaíba (CP) e sucupira (SC) na alimentação de poedeiras sobre a oxidação lipídica de ovos in natura armazenados em temperatura ambiente (TA) por 30 dias e sob refrigeração (R) a 4ºC por 60 dias, e de gemas cozidas mantidas sob R por 30 dias. As poedeiras foram alimentadas com ração isoproteica (15% PB) e isoenergética (2900 kcal kg-1) à base de milho e farelo de soja, com inclusão de óleo de Copaifera langsdorffii (CP) nas proporções de 0,03; 0,06 e 0,09% ou de Pterodon emarginatus (SC) nas proporções de 0,03 e 0,06%, mais um controle negativo (CN). Foram coletados 667 ovos às 37 semanas de idade e distribuídos aleatoriamente nas diferentes condições de armazenamento (TA ou R). A oxidação dos lipídios de ovos in natura foi quantificada em quadruplicata e das gemas cozidas em duplicata, utilizando-se pool de 3 gemas/tratamento para as análises de TBARS (thiobarbituric acid reactive substances). Os dados foram avaliados adotando um modelo misto e as médias foram comparadas pelo teste de Tukey em 5% de nível de significância e o período de armazenamento foi considerado como um fator longitudinal, variando de cinco tempos no experimento com gemas cozidas, e nos ovos in natura sob R e em TA (0 a 30 dias), até nove tempos sob R (0 a 60 dias). Foi observado que a adição de óleo de CP e SC não reduziu os valores de TBARS em ovos in natura armazenados em TA e sob R em relação ao CN. No armazenamento de gemas cozidas, a inclusão CP (0,03 e 0,06%) protegeu os lipídios até os 21 dias, mas apresentou efeito pró-oxidante quando suplementado a 0,09%. Concluiu-se que a inclusão de até 0,06% de óleorresina de CP nas rações de poedeiras pode proteger os lipídios da gema cozida contra a oxidação durante o armazenamento refrigerado por até 21 dias...
Subject(s)
Animals , Antioxidants/analysis , Egg Yolk/chemistry , Lipid Peroxidation , Plant Oils/therapeutic use , Animal Feed/analysis , Chickens , Spectrophotometry/veterinary , Eggs/analysis , Thiobarbituric Acid Reactive Substances/analysisABSTRACT
La listeriosis es una enfermedad transmitida por alimentos (ETA) y ocasionada por Listeria monocytogenes. La importancia de ésta se debe a su impacto clínico, la alta tasa de mortalidad y el efecto económico derivado de los brotes asociados con el consumo de alimentos. En México, las fallas en los sistemas de vigilancia epidemiológicos son causa de información imprecisa sobre la incidencia de la listeriosis y sobre su caracterización como ETA. En este trabajo se presentan datos referentes a la presencia de la bacteria en alimentos, reportes de casos de la enfermedad y patologías relacionadas con infección por L. monocytogenes. La falta de datos exactos sobre la importancia de esta bacteria plantea la necesidad de concientizar a las instancias correspondientes para definir estrategias de búsqueda intencionada de L. monocytogenes en alimentos y de la recopilación de información clínica precisa que permita conocer la importancia clínica y epidemiológica de la listeriosis en México.
Listeriosis is caused by Listeria monocytogenes, an important food-borne disease due to its clinical forms, high mortality rate, and the economic impact in both clinical and food production industries. In Mexico, the lack of epidemiological surveillance systems leads to the need of accurate data on the incidence of listeriosis and its association with food-borne disease. In this paper, we present data about the presence of this bacterium in food, reports related to clinical cases of listeriosis, and information of diseases in which L. monocytogenes may be involved. However, in most of these cases the etiology was not established. Given this, there's a need to inform and warn the appropriate entities, to define strategies for the mandatory search of L. monocytogenes through the whole food production chain and clinical suspects, for the epidemiological importance and control of listeriosis in Mexico.
Subject(s)
Animals , Cysteine Endopeptidases/isolation & purification , Egg Proteins/metabolism , Enzyme Precursors/isolation & purification , Antimalarials/pharmacology , Chromatography, Gel , Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Egg Yolk/chemistry , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Enzyme Precursors/metabolism , Hydrogen-Ion Concentration , Leucine/analogs & derivatives , Leucine/metabolism , Molecular Weight , OrthopteraABSTRACT
A research was conducted to evaluate the effects of combined usage of garlic powder [GP] and cupric sulfate pentahydrate [CS] as two different cholesterol-lowering supplements on blood serum and egg yolk cholesterol concentration in laying hens. A total of one-hundred ninety two 40-wks-old Single Comb White Leghorn [SCWL] laying hens were selected in a completely randomized designed to four diets that included unsupplemental basal diet as control diet [CO], the basal diet supplemented with either 15 g/kg GP, 200 mg/kg CS, or both 15 g/kg GP and 200 mg/kg Cs for a period of 6 weeks. During the experimental period hens performance traits included body weight gain, egg production, egg and yolk weights, egg mass, feed consumption, and feed conversion ratio were recorded. For statistical analysis, data were averaged by replicate for 6 wks period. At the end of the experimental period blood serum and egg yolk samples were collected for cholesterol analysis. Supplementation of GP or CS to the basal diet had no significant [p>0.05] effect on overall performance in laying hens. A decrease in blood serum and egg yolk cholesterol concentration was found [p<0.01] in birds fed GP, CS, and GP/CS diets in comparison with the unsupplemented diet birds [CO diet].Serum cholesterol levels were reduced by feeding GP, CS, or both by about 14,20 and 28% respectively [p<0.01]. Feeding GP or CS decreased egg yolk cholesterol about 6 and 12.5%, respectively [p<0.01], but feeding both GP and CS diet/ supplements had no further beneficial effect on egg yolk cholesterol
Subject(s)
Animals , Garlic , Copper Sulfate , Egg Yolk/chemistry , Body Weight , CopperABSTRACT
Con el propósito de determinar la influencia de la alimentación habitual de las gallinas en Chile-la que podría producir huevos comparables a los denominados "enriquecidos" en otros países- sobre la composición química de los huevos, se analizaron huevos de producción industrial, provenientes de gallinhas alimentadas con harina de pescado y grasas marino-vegetales y huevos de gallinas alimentadas sólo con alimentos de origen vegetal, a modo de grupo control. Se determinaron los ácidos grasos de la yema y contenidos de colesterol, triglicéridos y fosfolípidos de los lípidos de la yema, además de la composición en macronutrientes. Los huevos de gallinas alimentadas con productos de origen marino contienen significativamente menos colesterol, más triglicéridos y menos fosfolípidos que aquellos provenientes de gallinas alimentadas sólo con productos de origen vegetal. Aún cuando no hubo diferencias en contenidos de ácidos grasos de la serie n-3 (7,13+0,83 para el grupo con productos marinos vs. 1,77+0,55 g/100g, para el grupo con productos vegetales) y de la serie n-6 (15,17+2,51 para el grupo con productos marinos vs. 20,88+2,32 g/100g. para grupo con productos vegetales). Estas observaciones sugieren que los huevos que habitualmente se producen en Chile, presentan características análogas a las de los huevos enriquecidos, las que permiten replantear su valor nutricional, especialmente en grupos poblacionales vulnerables.
Subject(s)
Animals , Egg Yolk/chemistry , Eggs/analysis , Fatty Acids/analysis , Lipids/analysis , Animal Feed , Chickens , SeafoodABSTRACT
The dielectric properties of albumin and yolk of eggs of hen and duck have been investigated using the time domain reflectometry (TDR) technique in the frequency range 10 MHz to 10 GHz at room temperature. The conductivity and pH values were also measured. It has been found that the values of dielectric constant (epsilon s) is lower, while the values of relaxation time tau(ps) are higher than that of pure water possibly due to the bound water present in the yolk and albumin of the avian egg. The dielectric constant for albumin is more than that for yolk of eggs, while reverse is found with the values of relaxation time. Also albumin shows approximately three times higher conductivity than that of yolk. In the case of relatively older (by 2 days) eggs, the dielectric parameters tend to be slightly increased.