Browsing by Subject "Freezing"

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    Effect of industrial processing on desert truffles (Terfezia claveryi Chatin and Picoa juniperi Vittadini): proximate composition and fatty acids
    (Wiley, Society of Chemical Industry, 2003-05) Murcia Tomás, María Antonia; Martínez Tomé, Magdalena; Vera, Ana; Gutierrez, Almudena; Honrubia, Mario; Jiménez Monreal, Antonia M.; Morte Gómez, María Asunción; Tecnología de Alimentos, Nutrición y Bromatología
    Our objectives were to investigate the proximate composition of two desert truffles (Terfezia claveryi Chatin and Picoa juniperi Vittadini) and to determine the effects of freezing and canning on proximate composition. The moisture content of T claveryi and P juniperi was 730.9 g kg−1 and 637.8 g kg−1 respectively; ash was 42.5 g kg−1 and 82.1 g kg−1 respectively; protein was 159.5 g kg−1 and 225.4 g kg−1 respectively; lipids were 69.5 g kg−1 and 199.4 g kg−1 respectively; fibre was 83.2 g kg−1 and 130.4 g kg−1 respectively; and carbohydrates were 645.5 g kg−1 and 366.6 g kg−1 respectively. The fatty acids composition showed high quantities of linoleic acid 18:2 (45.4% in T claveryi and 53.0% in P juniperi), the rest of the fatty acids in decreasing order were 16:0 > 18:1 > 18:3 > 18 : 0 + 22 : 0 > 20 : 0 + 24 : 0 > 14 : 0 + 22 : 1 > 15 : 0 + 16 : 1 + 17 : 0 + 21 : 0 in T claveryi and 18 : 1 > 16 : 0 > 18 : 0 + 18 : 3 + 16 : 1 + 20 : 0+22:1 > 14:0 + 24:0 > 15:0 + 17:0 + 22:0 in the P juniperi. Little loss of ash, protein and lipids was observed as a result of industrial processing (p < 0.05).
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    Post-Thaw quality of spermatozoa frozen with three different extenders in the Murciano Granadina goat breed.
    (MDPI, 2023-01-16) Galián, S.; Peinado, B.; Almela, L.; Poto, A.; Ruiz, S.; Fisiología
    In caprine species, the semen quality of thawed samples still needs to be improved in order for this type of semen to provide an acceptable pregnancy rate when it is used for artificial insemination. It is therefore essential to have an adequate freezing protocol and extender for this species. By adapting freezing protocols that have proven successful in other species, such as pigs, together with the development of an extender that protects the sperm cells from damage caused by the freezing and thawing processes, and taking into account its composition in nutrients and cell-membrane-stabilizing substances, it has been possible, at least in vitro, to achieve high sperm quality in buck semen. In vivo studies of the fertilizing capacity of the semen cryopreserved in this way will be the next step to verify the effectiveness of the extender and semen-freezing protocol described in this work.
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    Revisitando el nudo gordiano : el desarrollo de la congelación en la pesca gallega (1960-1970)
    (Murcia : Editora Regional de Murcia, 2008) Giráldez Rivero, Jesús; Editora Regional de Murcia
    Este artículo pretende avanzar en el estudio de la pesca marítima en un momento clave de su desarrollo, la denominada por Paz-Andrade “tercera etapa de expansión” de las pesquerías españolas, cuando comenzaron a explotarse los caladeros atlánticos del hemisferio sur, bajo la tecnología de la congelación. Se trata de analizar la evolución de las principales magnitudes (flota, desembarcos, precios, etc.), las bases en que se asentó esta expansión, el papel jugado por el estado y sus protagonistas: las empresas. El trabajo finaliza a comienzos de los años setenta, cuando quebró el marco de aguas libres que había caracterizado la actividad pesquera española, por la redefinición de los derechos de pesca a escala internacional, con la rápida extensión de las doscientas millas, y cuando diversos problemas, como el aumento de los costes de producción o el descenso de los rendimientos, pusieron en cuestión las bases de su desarrollo.
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    Stability Study of Meropenem 50 mg/mL Eye Drops in Polypropylene Dropper Bottles
    (MDPI, 2026-08-07) Ruiz Ramírez, Juan Carlos ; Martínez Madrid, María Encarnación ; Gómiz Sáez, Adrián ; Charlotte Viney, Alice ; Alonso Herreros, José María ; Pilar Almela Rojo; Almela Rojo, Pilar; Farmacología
    Background/Objectives: Meropenem is a broad-spectrum carbapenem antibiotic with demonstrated efficacy against multidrug-resistant Gram-negative pathogens. Although its use as an ophthalmic formulation is off-label, growing clinical evidence supports its application in severe ocular infections such as keratitis and endophthalmitis. However, the intrinsic instability of meropenem in aqueous solutions and the absence of standardized ophthalmic preparations limit its routine use. Furthermore, no stability studies are currently available for meropenem 50 mg/mL eye drops stored in polypropylene (PP) dropper bottles under freezing and subsequent refrigerated conditions. The aim of this study was to evaluate the physicochemical and microbiological stability of a 50 mg/mL meropenem ophthalmic solution prepared in a hospital pharmacy using a commercial meropenem pharmaceutical product, and packaged in PP containers. Methods: Eye drops were aseptically prepared from a commercially available pharmaceutical product, containing 1g de meropenem and anhydrous sodium carbonate as an excipient. After preparation, the drops were stored at -20 ± 2 °C for up to 42 days, followed by refrigerated storage (5 ± 3 °C) after thawing for up to 7 days. Chemical stability was assessed using a validated stability-indicating HPLC method in accordance with ICH guidelines and was defined as 90-110% recovery of the initial concentration. Physical stability (appearance, pH, particulate matter) and microbiological stability were also evaluated under simulated in-use conditions. Results: The HPLC method demonstrated excellent linearity, precision, and accuracy. Meropenem concentrations remained within the predefined acceptance limits throughout the 42-day study period under freezing conditions, with no significant changes in pH, color, or particulate formation. After thawing, a progressive decrease in drug concentration was observed under refrigerated conditions, falling below 90% of the initial concentration within 24-48 h. A concomitant color change from colorless to yellow was also detected, consistent with β-lactam ring hydrolysis. Despite this degradation, no significant changes in physical parameters other than color were observed, and microbiological testing confirmed sterility for up to 7 days under refrigerated conditions. Conclusions: Meropenem drops 50 mg/mL in PP dropper bottles are physicochemically and microbiologically stable for 43 days (42 days under frozen conditions plus 1 day, in-use conditions, after opening and under refrigeration).