No abstract

To achieve a suitable packaging configuration, it is important first to determine the physicochemical characteristics related to the packaged product. In this study, the physicochemical characterization of fresh purple passion fruits of three different ripening stages was carried out to determine key variables for the packaging, such as O 2 consumption and CO 2 -ethylene production rates.Subsequently, intermediate-ripe fruits were packaged for 21 days at 6 • C under three packaging conditions: Xtend R perforated bags, low-density polyethylene (LDPE) bags, and LDPE bags with a novel ethylene scavenger active additive (ESAA). It was observed that an equilibrium modified atmosphere was formed in the packages. For the Xtend R bags, the highest values of O 2 (yo 2 = 0.184 to 0.192) and lowest of CO 2 (yco 2 = 0.033 to 0.041) were reached, whereas for the LDPE bags with ESAA these values were moderate. In the case of ethylene, the LDPE bags showed the highest levels in the headspace (26 to 31 ppm), whereas the lowest levels were obtained in the LDPE bags with additive (2 to 4 ppm).These levels resulted in a delay in the ripening of the fruits during storage, which was verified through a sensory acceptability test that was carried out on the juice extracted from the fruits. In this sensory test, panelists identified similar characteristics between the fruits packaged with ESAA and the Xtend R bags, regarding the control fruits. The LDPE bags with the ethylene scavenger performed satisfactorily and can considerably delay the ripening, which may result in longer shelf life and conservation of fresh purple passion fruits.Practical Application: This work presents a novel packaging proposal that reduces oxygen and ethylene levels in contact with purple passion fruits. Our proposed active packaging can be used to increase the fruit shelf life by improving its conservation conditions throughout the chain of storage, transport, and distribution in the market. With this, it will be possible to reduce the fruit's

<p>Se examinaron las respuestas gráficas de hombres y mujeres jóvenes, de 17 años en promedio, inscritos en cursos de nivelación en ciencias. Se encontró que predominan en toda la población alusiones a material de laboratorio y a experimentos. La categoría denominada Iconos/Iconemas (representaciones de sensaciones o sentimientos, o figuras geométricas aisladas) aparece con frecuencia en la población de 17 años. Los análisis muestran que el porcentaje de población que incluye el cuerpo humano en sus expresiones nunca es superior al 30 %. Cuando aparecen figuras humanas sus escenarios dejan ver que son experimentadores, no se muestra el cuerpo humano como parte del estudio químico. Al indagar sobre la orientación vocacional, se encontró que los hombres prefieren carreras científicas y las mujeres optan por programas del área de la salud. El artículo concluye que es posible indagar y analizar la percepción esencial sobre el área de la química gracias al estudio de expresiones gráficas y considerar correspondencias entre edad, sexo y orientación vocacional. Esta información es útil tanto para planear y orientar las actividades de aula, como para inquirir paradigmas y concepciones, y establecer el grado de abstracción y el conocimiento de los estudiantes sobre el alcance y la aplicabilidad de la química.</p>

This paper exposes a methodological approach that was designed and developed to facilitate the understanding of the topic chemical equilibrium; a familiar context for students was used. The proposal was applied to an average 1 Producto derivado del proyecto de investigación "Herramienta didáctica para la comprensión del concepto de equilibrio químico a partir del

Summary Colombia has a biodiversity centre of diploid potatoes located at south of the country. This study evaluated the amounts of potassium (K), calcium (Ca), iron (Fe) and zinc (Zn) in a biodiversity panel of potato tubers, constituting native cultivars, accessions of the Working Collection of Potato Breeding Program at the Universidad Nacional de Colombia (CCC) and commercial cultivars. The highest quantity of minerals found were as follows: 34 333 ± 4509 mg K kg−1 potato dry weight (DW; CCC112), 1965 ± 898 mg Ca kg−1 potato DW (CCC23), 87.5 ± 8.8 mg Fe kg−1 potato DW (CCC116) and 60.7 ± 5.1 mg Zn kg−1 potato DW (CCC31). As compared to those in commercial cultivars, the currently evaluated tubers had an increase of 1.4, 12.5, 3.5 and 3.6‐fold in K, Ca, Fe and Zn. These genotypes can be used in the future breeding programmes to enhance specific mineral contents in tubers.