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Studies on how washing and storage influence duck egg quality are scarce compared with those on chicken egg quality. The present study investigated the quality of washed and unwashed duck eggs stored at 7 ºC and 25 ºC for 8 weeks. Quality parameters, including Haugh unit (HU), yolk index, thick albumen ratio, albumen pH, and air cell size, indicated that egg quality deteriorated during prolonged storage, and cuticle staining confirmed that washing reduced cuticle coverage. Washed eggs stored at 7 ºC maintained high quality (grade B; HU: 54) according to the United States Department of Agriculture (USDA, 2000) after storage for 8 weeks, whereas unwashed eggs stored at 25 ºC exhibited a low but acceptable quality (grade B, but HU: 36) after 7 weeks. Strong correlations were observed between the quality parameters evaluated. In conclusion, duck eggs should be washed and then stored at 7 ºC to enhance microbial safety and maintain quality to achieve a shelf life of at least 8 weeks.(AU)

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The shipping of liquid preserved semen is common practice in animal breeding and prior to cryopreservation for gene banking. Vibration emissions during transport may be harmful to spermatozoa. Therefore, strategies to minimize agitation-induced sperm injury are needed. The aim was to examine whether the type of semen extender, time after semen processing and the temperature in simulated transport conditions influence the response of boar spermatozoa to agitation stress. In Experiment 1, boar semen samples (n = 16) extended in Beltsville Thawing Solution (BTS) or Androstar Plus (APL) medium were filled in 90 mL tubes and shaken for 4 h at 200 rpm either at 22 °C or 17 °C. Samples were then stored at 17 °C for 144 h. In Experiment 2, semen samples (n = 11) extended in Androstar Premium were shaken either directly after filling at 22 °C or 20 h later after cooling to 5 °C. Samples were stored at 5 °C for 144 h. In Experiment 1, sperm motility and viability were lower (p < 0.05) in the shaken samples compared to the controls. The temperature, extender and the storage length had no effect on the agitation-induced loss of sperm quality. Sperm quality traits were higher in samples stored in APL compared to BTS. In Experiment 2, sperm motility at 24 h was reduced (p < 0.05) in those samples shaken at 22 °C but not at 5 °C. Sperm viability, membrane fluidity and mitochondrial membrane potential were not affected in either of the treatment groups. Extended boar semen designed for 17 °C storage and shipped on the day of collection is sensitive to agitation stress. In contrast, spermatozoa slowly cooled to 5 °C and shaken 20 h after processing are more resistant to agitation-induced shear forces and interfacial phenomena.

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INTRODUCTION: Minas fresh cheese (MFC), a Brazilian white cheese, is one of the most popular cheeses nationwide. Studies have shown that Listeria monocytogenes occurrence in this product is generally low, while high populations of coliforms can be found. This study aimed to evaluate the influence of coliforms in the behavior of L. monocytogenes in MFC. METHODS: Pasteurized milk was inoculated with L. monocytogenes and coliforms, and the acidification was made by lactic acid or by the addition of a starter culture. The cheeses of each production were divided into 3 groups and stored at 5 ºC, 12 ºC and cycles of 5 ºC followed by 25 ºC. In predetermined days, samples were taken and L. monocytogenes, coliforms and lactic acid bacteria populations were evaluated, besides the pH, water activity (aw), titratable acidity and NaCl concentration. RESULTS: The inhibition of L. monocytogenes in the presence of coliforms was observed (p < 0.05), except for those samples prepared with lactic acid and stored at temperature cycles. The values of pH and aw were not sufficiently low to cause inhibition; however, titratable acidity was higher in cheeses containing coliforms. In vitro tests containing lactic acid and L. monocytogenes showed that the bacterium is sensitive to concentration of lactic acid ≥ 0.3%, indicating that lactic acid produced by coliforms strongly influences the population of L. monocytogenes. CONCLUSIONS: Thus, it can be concluded that coliforms negatively impact populations of L. monocytogenes in MFC. We strongly recommend that producers of MFC adopt good hygiene practices to not only avoid contamination with L. monocytogenes, but also coliforms.

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Cocoa butter provides desirable sensory properties to chocolates; however, the exposure of chocolate to temperature variations during transportation and/or storage can lead to changes in the polymorphic form of butter, with the appearance of a dull-white film on the chocolate surface, known as fat bloom. This study investigated the use of a portable NIR spectrometer combined with chemometric tools to discriminate milk chocolate, white chocolate, 40% cocoa chocolate, and 70% cocoa chocolate samples, which were subjected to temperature abuse for 6 hours. The PCA allowed separating the samples into three classes: control at 20 °C, chocolate subjected to 35 °C, and chocolate subjected to 40 °C, for each type of chocolate studied. The PLS-DA models provided sensibility, specificity, and accuracy values in the range of 80 to 100%, and allowed identifying the wavelengths associated with the different chocolates that most impacted the construction of the models.

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The objective of this work was to evaluate the effect of storage time and temperature on the quality of quail eggs. The experimental design was completely randomized in split plots, with two storage temperatures in the plots and six storage periods in the subplots. The variables analyzed were: egg weight; albumen and yolk weight, height and pH; Haugh units (HU); and yolk index and diameter. ̈The interaction between storage time and temperature was not significant (P>0.05) for egg weight, yolk weight and pH, but was significant (P<0.05) for albumen height, weight and pH, HU, and yolk diameter, height and index. The storage period had a quadratic effect in the two storage conditions for HU, albumen pH, yolk height and index, while for eggs stored at room temperature there was a quadratic effect on egg and albumen weight, albumen height, yolk weight, diameter and pH. In turn, for eggs kept under refrigeration, the effect of the storage period was linear for egg weight, albumen weight and height, yolk weight and pH. There was no effect in the regression analysis of the storage period for the yolk diameter of the eggs stored under refrigeration. The storage conditions influenced the egg weight and quality characteristics of the albumen and yolk, but had no effect on the yolk weight. Non-refrigerated eggs presented lower averages for all the characteristics except albumen pH, and yolk pH and diameter. During the entire storage period, the quality of the eggs without refrigeration remained lower than that of refrigerated eggs. Thus, to preserve quality, quail eggs should be stored under refrigeration.(AU)

O objetivo do trabalho foi avaliar o efeito da temperatura e do tempo de estocagem na qualidade de ovos de codorna. O delineamento foi inteiramente casualizado em parcela subdividida, sendo duas temperaturas de armazenamento nas parcelas e seis períodos de estocagem nas subparcelas. As variáveis analisadas foram: peso do ovo, peso, altura, pH do albúmen e da gema, Unidades Haugh (UH), diâmetro e índice de gema. A interação entre período e temperatura de armazenamento não foi significativa (P>0,05) para o peso do ovo, pH e peso da gema. Contudo foi significativa (P<0,05) para altura do albúmen, peso, pH do albúmen, UH, diâmetro, altura e índice de gema. O período de estocagem teve efeito quadrático nas duas condições de estocagem para: UH, pH do albúmen, altura e índice de gema e para ovos armazenados em condições ambientes para: peso do ovo e do albúmen, altura de albúmen, peso, diâmetro e pH da gema. Para os ovos mantidos em refrigeração o efeito do período de estocagem foi linear para: peso do ovo e do albúmen, altura de albúmen, peso e pH da gema. Não houve regressão do período de estocagem para o diâmetro da gema dos ovos armazenados em refrigeração. As condições de estocagem influenciaram o peso do ovo e as características de qualidade do albúmen e da gema, porém não teve efeito sobre o peso da gema. Os ovos sem refrigeração apresentaram médias inferiores para a maioria das características exceto para o pH do albúmen, pH e diâmetro da gema. Durante todo o período de estocagem, a qualidade dos ovos sem refrigeração manteve inferior aos ovos refrigerados. Para preservar a qualidade, os ovos de codorna devem ser armazenados em refrigeração.(AU)

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This study aimed to assess the sperm quality and number of colony-forming units (CFU mL-1) in extended boar semen stored at low temperatures with or without antibiotics. Normospermic ejaculates (n = 34) were diluted in split samples with Androstar® Premium with or without antibiotics (ampicillin and apramycin sulfate). The extended semen doses were stored for 120 h under three storage temperatures (5, 10, and 17 °C). Variables were analyzed as repeated measures using the GLIMMIX procedure, in a factorial design. The extended semen doses under low-temperature storage (5 and 10 °C) had total motility above 75% throughout the storage. The interaction antibiotic × temperature was significant for total (P = 0.004) and progressive motility (P = 0.005). In extended boar semen doses with antibiotics, the total and progressive motility increased as the storage temperature increased (80.2%, 84.5%, and 89.1%; 70.5%, 76.0%, and 82.9% for total and progressive motility at 5, 10, and 17 °C, respectively; P < 0.05). In extended semen doses without antibiotics, the total and progressive motility were lower when stored at 5 °C than at 10 °C and 17 °C (81.8%, 85.4% and 86.6% and 71.9%, 76.7%, 78.9% for total and progressive motility at 5, 10, and 17 °C, respectively; P < 0.05). After the thermoresistance test, total and progressive motility of doses with antibiotics were higher at 17 °C than 5 °C (P < 0.05); however, they were not affected (P > 0.05) by storage temperature in extended semen doses without antibiotics. The number of CFU mL-1 was lower in extended semen doses without antibiotics stored at 5 and 10 °C than at 17 °C (P < 0.05); however, in extended semen doses with antibiotics, no effect of storage temperature was observed (P > 0.05). The bacterial load was greater in extended semen without antibiotics than with antibiotics, regardless of the storage temperature (P < 0.05). The acrosome and sperm membrane integrity were not influenced (P > 0.05) by using antibiotics. A higher percentage of normal acrosomes was observed as the storage temperature increased (93.6%, 94.3%, and 96.8% at 5, 10, and 17 °C, respectively; P < 0.0001). The membrane integrity was higher (P < 0.0001) in extended semen doses stored at 17 °C than at 10 or 5 °C. The pH rose throughout the storage in all the treatments, except in extended semen doses stored at 17 °C without antibiotics, in which a decrease in the pH occurred at 120 h (P < 0.05). Although the sperm quality being negatively affected by low temperatures, the storage of extended boar semen doses at 5 °C is possible since the sperm viability in vitro was maintained for up to 5 days, fulfilling the requirements of semen quality to be used in artificial insemination. Nevertheless, the use of extended semen doses without antibiotics requires the optimization of hygiene procedures during semen dose processing.

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The objective of this work was to evaluate the effect of storage time and temperature on the quality of quail eggs. The experimental design was completely randomized in split plots, with two storage temperatures in the plots and six storage periods in the subplots. The variables analyzed were: egg weight; albumen and yolk weight, height and pH; Haugh units (HU); and yolk index and diameter. ̈The interaction between storage time and temperature was not significant (P>0.05) for egg weight, yolk weight and pH, but was significant (P<0.05) for albumen height, weight and pH, HU, and yolk diameter, height and index. The storage period had a quadratic effect in the two storage conditions for HU, albumen pH, yolk height and index, while for eggs stored at room temperature there was a quadratic effect on egg and albumen weight, albumen height, yolk weight, diameter and pH. In turn, for eggs kept under refrigeration, the effect of the storage period was linear for egg weight, albumen weight and height, yolk weight and pH. There was no effect in the regression analysis of the storage period for the yolk diameter of the eggs stored under refrigeration. The storage conditions influenced the egg weight and quality characteristics of the albumen and yolk, but had no effect on the yolk weight. Non-refrigerated eggs presented lower averages for all the characteristics except albumen pH, and yolk pH and diameter. During the entire storage period, the quality of the eggs without refrigeration remained lower than that of refrigerated eggs. Thus, to preserve quality, quail eggs should be stored under refrigeration.

O objetivo do trabalho foi avaliar o efeito da temperatura e do tempo de estocagem na qualidade de ovos de codorna. O delineamento foi inteiramente casualizado em parcela subdividida, sendo duas temperaturas de armazenamento nas parcelas e seis períodos de estocagem nas subparcelas. As variáveis analisadas foram: peso do ovo, peso, altura, pH do albúmen e da gema, Unidades Haugh (UH), diâmetro e índice de gema. A interação entre período e temperatura de armazenamento não foi significativa (P>0,05) para o peso do ovo, pH e peso da gema. Contudo foi significativa (P<0,05) para altura do albúmen, peso, pH do albúmen, UH, diâmetro, altura e índice de gema. O período de estocagem teve efeito quadrático nas duas condições de estocagem para: UH, pH do albúmen, altura e índice de gema e para ovos armazenados em condições ambientes para: peso do ovo e do albúmen, altura de albúmen, peso, diâmetro e pH da gema. Para os ovos mantidos em refrigeração o efeito do período de estocagem foi linear para: peso do ovo e do albúmen, altura de albúmen, peso e pH da gema. Não houve regressão do período de estocagem para o diâmetro da gema dos ovos armazenados em refrigeração. As condições de estocagem influenciaram o peso do ovo e as características de qualidade do albúmen e da gema, porém não teve efeito sobre o peso da gema. Os ovos sem refrigeração apresentaram médias inferiores para a maioria das características exceto para o pH do albúmen, pH e diâmetro da gema. Durante todo o período de estocagem, a qualidade dos ovos sem refrigeração manteve inferior aos ovos refrigerados. Para preservar a qualidade, os ovos de codorna devem ser armazenados em refrigeração.

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The effects of sugar component ratio, water fraction, and storage conditions on crystallisation and glass transition temperature (Tg) of three Chilean dried raisins were examined by using differential scanning calorimetry (DSC), polarised light microscopy and X-ray diffraction (XRD) techniques. Thompson, Flame and Golden raisins differed in fructose:glucose and glucose:water ratios, impacting on their measured Tgs (P < 0.05) and propensity of sugaring. The ratios of fructose:glucose (1:3, 1:2 and 1:1) and glucose:water (1.7, 1.9 and 2.1) also influenced the measured Tgs (P < 0.05) and sugaring of fructose-glucose-water model solutions. Measurement of Tgs in the raisins as a function of water activity (aw 0.11-0.74) showed that water acts as a strong plasticiser decreasing the Tgs (-16.4 to -61.6 °C). XRD results revealed that sugaring in Thompson raisins was delayed at low temperatures (5 & 15 °C) compared to that stored at 25 °C. The refrigeration may be a simple approach to delay the sugaring in raisins.

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BACKGROUND: Hypothermic storage at 5°C has been investigated as an alternative to promote the prudent use of antibiotics for boar artificial insemination doses. However, this temperature is challenging for some ejaculates or boars. OBJECTIVE: The present study aimed to identify putative biomarkers for semen resistance to hypothermic storage at 5°C by comparing the seminal plasma proteomes of boars with high and low seminal resistance to preservation at 5°C. MATERIALS AND METHODS: From an initial group of 34 boars, 15 were selected based on the following criteria: ejaculate with ≤20% abnormal spermatozoa and at least 70% progressive motility at 120 hours of storage at 17°C. Then, based on the response to semen hypothermic storage at 5°C, boars were classified into two categories: high resistance-progressive motility of >75% in the three collections (n = 3); and low resistance-progressive motility of <75% in the three collections (n = 3). Seminal plasma proteins were analyzed in pools, and differential proteomics was performed using Multidimensional Protein Identification Technology. RESULTS: Progressive motility was lower at 120 hours of storage in low resistance, compared to high resistance boars (P < .05). Acrosome and plasma membrane integrity were not affected by the boar category, storage time, or their interaction (P ≥ .104). Sixty-five proteins were considered for differential proteomics. Among the differentially expressed and exclusive proteins, the identification of proteins such cathepsin B, legumain, and cystatin B suggests significant changes in key enzymes (eg, metalloproteinases) involved in spermatogenesis, sperm integrity, and fertilizing potential. DISCUSSION AND CONCLUSION: Differences in the seminal plasma suggest that proteins involved in the proteolytic activation of metalloproteinases and proteins related to immune response modulation could disrupt key cellular pathways during spermatogenesis and epididymal maturation, resulting in altered resistance to chilling injury. Further in vivo studies focusing on the immunological crosstalk between epithelial cells and gametes might explain how the immune regulators influence sperm resistance to hipothermic storage.

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Malbec is the flagship variety of Argentina mainly due to its high oenological value and plasticity to obtain different wine styles. During bottled aging, the chemical and organoleptic composition of wines is subject to changes depending on the aging conditions (closure, oxygen level, temperature, time). However, the combined effect of these factors on chemical composition and organoleptic characteristics of Malbec wines has not been studied yet. Wines were bottled with screw cap and natural cork and were kept in chambers at 15 °C and 25 °C for 2 years. Sampling was performed at 2, 4, 6, 9, 12, 15, 18, 21 and 24 months. Concentrations of free sulfur dioxide, dissolved oxygen, anthocyanins, tannins, esters, volatile phenols, organic acids, and color saturation decreased during the storage process. While, the formation of polymeric pigments, the color attributes (lightness and hue) and the levels of alcohols, norisoprenoids, furanoids and terpenoids increased. At 24 months, Malbec wines were organoleptically different. Wines kept at 15 °C were associated with high sensory perceptions in color intensity and violet tint, those presented a positive correlation with free sulfur dioxide, tannins, and anthocyanins levels. On the contrary, wines aged at 25 °C were linked with high sensory perceptions of dried vegetative and dried fruit aromas. These descriptors were positively correlated with norisoprenoids, furanoids, and terpenoids. In general, the chemical composition and organoleptic attributes of bottled Malbec wines (Mendoza, Argentina) were stable respect closure type employed, but highly sensitive to the combined effect of time and storage temperature. This finding is key to making decisions about the wine style searched, and costs (e.g. refrigeration) involved in the conservation period until consumption.

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The aim of this study was to manufacture pasta filata cheeses added with two probiotic lactobacilli: Lactobacillus rhamnosus GG and Lactobacillus acidophilus LA5, either individually or combined, and to evaluate the effect of the storage temperature (4 and 12 °C) on their chemical, microbiological, and sensorial characteristics. Three cheese types were made: (i) G: containing L. rhamnosus GG, (ii) L: containing L. acidophilus LA5, and (iii) GL: containing both probiotic strains. Gross composition, pH, microbiological, and sensory characteristics were determined. No differences in gross composition were found among them. pH values remained above 5.2 in cheeses stored at 4 °C. However, a postacidification was observed in cheeses ripened at 12 °C. L. acidophilus LA5 was not able to grow, while L. rhamnosus GG grew 1.5 log10 CFU/g in G and GL cheeses stored at 12 °C, reducing the pH from day 8 onwards. These results emphasize the importance of the storage temperature since the good characteristics of probiotic cheeses are kept if the cold-chain is respected. Thus, the selection of probiotics, together with the food matrix and the starter, should be carefully evaluated.

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INTRODUCTION: Sample stability is essential to obtain reliable results in the clinical laboratory. This study was conducted to investigate the reliability of hematological parameters using ABX Pentra 60 in samples stored for up to 72 hours at different temperatures. METHODS: A total of 651 blood samples were analyzed at different analysis times: 2, 24, 48, and 72 hours and forms and storage: room temperature (25°C) and at 4°C. The imprecision of the results was evaluated by the analytical coefficient of variation (CVa%) obtained by the typical error (TE) and Kruskal-Wallis analysis, to compare the averages. The reliability of the results was evaluated by the CVa (%) within the maximum allowable analytical variation and by the difference of means of the results in relation to the baseline sample (2 hours). RESULTS: Red blood count, hemoglobin, and MCH parameters showed stability up to 72 hours at room temperature and at 4°C. The other complete blood count parameters showed imprecision results emitted by the ABX Pentra 60 from 24 hours of sample storage, independent of the storage temperature. In addition, there were significant oscillations in the mean values, particularly for the samples stored at room temperature, with the exception of platelet parameters that exhibited mean changes also at 4°C. CONCLUSION: The results demonstrate the importance of the clinical analyst's knowledge about the behavior of the CBC parameters over time under different storage conditions, and mainly the imprecision of the hematological equipment used, for the suitable interpretation of the results.

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This study evaluated the spin concentration and the crystallinity in different classifications of dental composites as a function of the material condition (new, aged and expired). Specimens were obtained according to the factors: composites: Filtek P60, Filtek Z250, Filtek Z350XT, and Filtek Silorane; and material conditions: new, aged, and expired. The syringe composites underwent an accelerated aging protocol (Arrhenius model). The magnetic properties of the composites were characterized using Electron Paramagnetic Resonance (EPR) and the concentration of spins (number of spins/mass) was calculated. The crystallinity of the composites tested was characterized with X-ray diffraction (XRD). Filtek P60 and Filtek Z250 presented similarities in terms of spin concentration and crystallinity, irrespective of the material condition. The aging protocol influenced the composite Filtek Z350XT that exhibited a significant increase in the spin concentration. Besides, lower intensity peaks of the organic matrix and amorphous silica were also observed for both aged and expired Filtek Z350XT. Although a significant lower spin concentration was observed for the silorane composite in comparison to that of the methacrylates, a decrease in the relative intensity of peaks of the amorphous region related to the organic components in the diffractograms was observed. The material conditions tested influence the crystallinity and the magnetic properties of the composites evaluated.

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O leite de cabra é produzido em pequena escala, o que torna necessária sua estocagem, permitida pela legislação brasileira. O presente trabalho teve por objetivo avaliar a ação do resfriamento e congelamento sobre as características físico-químicas e microbiológicas do leite de cabra. Não foi observada variabilidade nos valores médios de acidez, estabilidade ao álcool, densidade, gordura, proteína, sólidos totais e lactose após armazenamento sob frio. Não foi observada instabilidade ao calor em nenhuma das amostras analisadas. Verificou-se tendência à diminuição na contagem de células somáticas (CSS) no leite congelado em relação ao fresco e ao refrigerado. A quantificação (NMP) de coliformes totais e termotolerantes variou de < 3 (ausência de crescimento) à > 1.100 UFC/mL, independentemente do armazenamento. Entretanto, determinou-se contagem de coliformes totais e termotolerantes significativamente maior (p < 0,0001) nas amostras mantidas sob refrigeração. Na prova de lactofermentação, observaram-se coágulos digeridos, floculosos e sulcados sem estabelecer correlação entre estes e a contagem bacteriana. A CCS e a contagem microbiana são critérios adotados no pagamento pela qualidade no leite caprino, e a temperatura de armazenamento pode influir sobre elas.(AU)

The small-scale goat milk production requires its storage, and such operation is allowed by Brazilian laws. This study aimed at evaluating the cooling and freezing effects on physical-chemical and microbiological characteristics of goat milk. However, no variability was verified in average acidity, alcohol stability, density, fat protein, total solids and lactose values after cold storage. Heat instability was not observed in any of the analyzed samples. There was a decreasing tendency in the somatic cell count (SCC) of frozen milk in comparison to fresh and refrigerated milk. The quantification (NMP) of total and thermo-tolerant coliforms varies from < 3 (no growth) to > 1,100 UFC/mL, regardless of the storage method. However, a slightly higher count (p < 0.0001) was observed for total and thermo-tolerant coliforms in the samples kept under refrigeration. In the lacto-fermentation test, digested, flocculated and grooved clots were observed without establishing a correlation between them and the bacterial count. SCC and microbial count are the criteria adopted when paying for the quality of goat milk, and the storage temperature may affect these criteria.(AU)

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O leite de cabra é produzido em pequena escala, o que torna necessária sua estocagem, permitida pela legislação brasileira. O presente trabalho teve por objetivo avaliar a ação do resfriamento e congelamento sobre as características físico-químicas e microbiológicas do leite de cabra. Não foi observada variabilidade nos valores médios de acidez, estabilidade ao álcool, densidade, gordura, proteína, sólidos totais e lactose após armazenamento sob frio. Não foi observada instabilidade ao calor em nenhuma das amostras analisadas. Verificou-se tendência à diminuição na contagem de células somáticas (CSS) no leite congelado em relação ao fresco e ao refrigerado. A quantificação (NMP) de coliformes totais e termotolerantes variou de < 3 (ausência de crescimento) à > 1.100 UFC/mL, independentemente do armazenamento. Entretanto, determinou-se contagem de coliformes totais e termotolerantes significativamente maior (p < 0,0001) nas amostras mantidas sob refrigeração. Na prova de lactofermentação, observaram-se coágulos digeridos, floculosos e sulcados sem estabelecer correlação entre estes e a contagem bacteriana. A CCS e a contagem microbiana são critérios adotados no pagamento pela qualidade no leite caprino, e a temperatura de armazenamento pode influir sobre elas.(AU)

The small-scale goat milk production requires its storage, and such operation is allowed by Brazilian laws. This study aimed at evaluating the cooling and freezing effects on physical-chemical and microbiological characteristics of goat milk. However, no variability was verified in average acidity, alcohol stability, density, fat protein, total solids and lactose values after cold storage. Heat instability was not observed in any of the analyzed samples. There was a decreasing tendency in the somatic cell count (SCC) of frozen milk in comparison to fresh and refrigerated milk. The quantification (NMP) of total and thermo-tolerant coliforms varies from < 3 (no growth) to > 1,100 UFC/mL, regardless of the storage method. However, a slightly higher count (p < 0.0001) was observed for total and thermo-tolerant coliforms in the samples kept under refrigeration. In the lacto-fermentation test, digested, flocculated and grooved clots were observed without establishing a correlation between them and the bacterial count. SCC and microbial count are the criteria adopted when paying for the quality of goat milk, and the storage temperature may affect these criteria.(AU)

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Los componentes activos del polen a partir del cual se obtienen los extractos alergénicos pueden variar considerablemente deacuerdo al momento, el lugar dónde se recolecta y el períodocomprendido entre la recolección y su utilización.El presente trabajo pretende evaluar si la temperatura de conservacióndel grano de polen influye en la expresión de proteínasy en la antigenicidad de las mismas, al momento de prepararun extracto alergénico. La especie elegida para estudio fue Chenopodiumalbum L. ya que es de gran interés alergológico en laciudad de Bahía Blanca. Los granos de polen se conservaron a temperatura ambiente, 4 °Cy -18 °C por el término de dos meses. El contenido proteico de losextractos se determinó por el Método de Bradford. La expresiónproteica y la antigenicidad se estudiaron mediante electroforesisvertical Tricina-PAGE-SDS 12, 5 % e Inmunoblot respectivamente.Los resultados obtenidos demuestran que la concentración proteicatotal fue menor para los extractos obtenidos del polen conservadoa temperatura ambiente que para las otras dos condiciones.La expresión de proteínas varía cuantitativamente en todoslos extractos y si bien la expresión cualitativa prácticamente seconserva, aparece para el polen conservado a temperatura ambiente,una banda de PM menor a 12 kDa. Esta banda podríaser consecuencia de la degradación proteica que experimenta elpolen a esa temperatura de almacenamiento. En cuanto a la antigenicidadde los extractos no hay diferencias cualitativas aunquepueden apreciarse diferencias cuantitativas significativas.Concluimos que la conservación del polen a 4°C o a -18°C seríanlas más adecuadas, ya que permiten obtener una mayor concentraciónproteica partiendo de la misma masa de polen.

The active components from which pollen allergen extracts are obtainedcan change considerably according to the time or the placewhere collect and the time period between harvesting and use.This work aims to assess if the storage temperature of the pollengrain influences protein expression and its antigenicity when preparingan allergen extract. The species chosen for our study wasChenopodium album L, since it is of great allergologic interest inthe city of Bahía Blanca.Pollen grains were stored at room temperature 4ºC and -18ºC ,for a period of two months. The protein content of the extractswas determined by the Bradford method. Protein expressionand antigenicity were studied by vertical electrophoresis TricineSDS-PAGE 12, 5% and Immunoblot. The obtained results show that the total protein concentrationwas lower in the extracts of pollen stored at room temperaturethan in those under two conditions. Protein expression differsquantitatively in all extracts and even if the qualitative expressionis kept practically the same, in the Tricine SDS-PAGE geland the pollen stored at room temperature there appear a bandof MW inferior to 12 kDa. This band could result from the proteindegradation experienced by pollen stored at that temperature.As regards extract antigenicity, there are no qualitative differenceseven though there are significant quantitative differences.We conclude that pollen preservation at 4ºC or -18ºC would bethe most appropriate since it allows greater protein concentrationfor the same mass of pollen.

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RESUMO

The small-scale goat milk production requires its storage, and such operation is allowed by Brazilian laws. This study aimed at evaluating the cooling and freezing effects on physical-chemical and microbiological characteristics of goat milk. However, no variability was verified in average acidity, alcohol stability, density, fat protein, total solids and lactose values after cold storage. Heat instability was not observed in any of the analyzed samples. There was a decreasing tendency in the somatic cell count (SCC) of frozen milk in comparison to fresh and refrigerated milk. The quantification (NMP) of total and thermo-tolerant coliforms varies from 3 (no growth) to > 1,100 UFC/mL, regardless of the storage method. However, a slightly higher count (p 0.0001) was observed for total and thermo-tolerant coliforms in the samples kept under refrigeration. In the lacto-fermentation test, digested, flocculated and grooved clots were observed without establishing a correlation between them and the bacterial count. SCC and microbial count are the criteria adopted when paying for the quality of goat milk, and the storage temperature may affect these criteria.

O leite de cabra é produzido em pequena escala, o que torna necessária sua estocagem, permitida pela legislação brasileira. O presente trabalho teve por objetivo avaliar a ação do resfriamento e congelamento sobre as características físico-químicas e microbiológicas do leite de cabra. Não foi observada variabilidade nos valores médios de acidez, estabilidade ao álcool, densidade, gordura, proteína, sólidos totais e lactose após armazenamento sob frio. Não foi observada instabilidade ao calor em nenhuma das amostras analisadas. Verificou-se tendência à diminuição na contagem de células somáticas (CSS) no leite congelado em relação ao fresco e ao refrigerado. A quantificação (NMP) de coliformes totais e termotolerantes variou de 3 (ausência de crescimento) à > 1.100 UFC/mL, independentemente do armazenamento. Entretanto, determinou-se contagem de coliformes totais e termotolerantes significativamente maior (p 0,0001) nas amostras mantidas sob refrigeração. Na prova de lactofermentação, observaram-se coágulos digeridos, floculosos e sulcados sem estabelecer correlação entre estes e a contagem bacteriana. A CCS e a contagem microbiana são critérios adotados no pagamento pela qualidade no leite caprino, e a temperatura de armazenamento pode influir sobre elas.

RESUMO

The influence of the packaging films, aerobic and vacuum conditions, and refrigeration storage temperature (0, 4 and 10 °C) on colour and texture of raw meat were studied during a 2-week storage period in order to analyze kinetics of colour and texture changes. The rate of redness decrease was most noticeable at the highest storage temperature and aerobic conditions and these changes were well described by the first-order reaction. Texture parameter reflected a progressive softening during storage for both films. Decrease on shear force of raw beef during storage followed a first-order kinetic model. Temperature dependence of colour and texture change was adequately modelled with the Arrhenius equation.

RESUMO

Considerando a importância nutricional e social da comercialização da carne suína, objetivou-se avaliar a qualidade da carne suína in natura em Mossoró-RN. Para isso,obteve-se 20 amostras de carne suína de vários estabelecimentos comerciais,verificando-se o número de bactérias mesófilas, coliformes totais e termotolerantes, Salmonella spp., temperatura, umidade e pH. Observaram-se elevadas contagens de micro-organismos mesófilos, coliformes totais e termotolerantes e contaminação por Salmonella spp. foi detectada em 25% das carnes analisadas. Além disso, constatou-se que a temperatura de armazenamento da carne suína apresentou média de 18,6°C e para as análises de pH e umidade verificaram-se média de 5,8 e 45,3% respectivamente. Dessa forma,observou-se que a carne suína comercializada em Mossoró-RN pode representar risco ao consumidor por possuir qualidade microbiológica insatisfatória. A temperatura de armazenamento apresentou-se inadequada para conservação do produto.

Considering the nutrition and social importance of pork, we aimed to evaluate the quality of pork in natura inMossoró-RN. For such, 20 samples of pork were taken from several commercial establishments, and the number of mesophilic bacteria, total and thermotolerant coliforms, the presence of Salmonella spp., the temperature, the humidity and the pH were mesured. High counts of mesophilic bacteria, total and thermotolerant coliforms were detected, and contamination by Salmonella spp. was observed in 25% of the samples tested. Furthermore, the storage temperature of pork presented an average value of 18.6°C, as for the pH and moisture analysis content observed had average of 5.8 and 45.3%, respectively. Thus, it was noticed that the pork sold in Mossoró-RN may pose a risk to consumer’s health for having unsatisfactory microbiological quality. The storage temperature was found inadequate to preserve the product.

Assuntos

RESUMO

Considerando a importância nutricional e social da comercialização da carne suína, objetivou-se avaliar a qualidade da carne suína in natura em Mossoró-RN. Para isso,obteve-se 20 amostras de carne suína de vários estabelecimentos comerciais,verificando-se o número de bactérias mesófilas, coliformes totais e termotolerantes, Salmonella spp., temperatura, umidade e pH. Observaram-se elevadas contagens de micro-organismos mesófilos, coliformes totais e termotolerantes e contaminação por Salmonella spp. foi detectada em 25% das carnes analisadas. Além disso, constatou-se que a temperatura de armazenamento da carne suína apresentou média de 18,6°C e para as análises de pH e umidade verificaram-se média de 5,8 e 45,3% respectivamente. Dessa forma,observou-se que a carne suína comercializada em Mossoró-RN pode representar risco ao consumidor por possuir qualidade microbiológica insatisfatória. A temperatura de armazenamento apresentou-se inadequada para conservação do produto.(AU)

Considering the nutrition and social importance of pork, we aimed to evaluate the quality of pork in natura inMossoró-RN. For such, 20 samples of pork were taken from several commercial establishments, and the number of mesophilic bacteria, total and thermotolerant coliforms, the presence of Salmonella spp., the temperature, the humidity and the pH were mesured. High counts of mesophilic bacteria, total and thermotolerant coliforms were detected, and contamination by Salmonella spp. was observed in 25% of the samples tested. Furthermore, the storage temperature of pork presented an average value of 18.6°C, as for the pH and moisture analysis content observed had average of 5.8 and 45.3%, respectively. Thus, it was noticed that the pork sold in Mossoró-RN may pose a risk to consumers health for having unsatisfactory microbiological quality. The storage temperature was found inadequate to preserve the product.(AU)

Assuntos