B. Diezma - Academia.edu (original) (raw)
Papers by B. Diezma
Global NEST International Conference on Environmental Science & Technology
Quantifying sustainability is a difficult but necessary task to improve our environmental, econom... more Quantifying sustainability is a difficult but necessary task to improve our environmental, economic, and social surroundings. This paper describes an investigation into the use of the Social Hotspot Database (SHDB) to determine the true value of fair-trade certification. The analysis has been carried out on two coffee systems produced in Colombia and consumed in Spain: i) a low-cost generic (GC) and ii) a high-quality organic fair trade certified (FTC). Risk levels in the SHDB for the cultivation sector in Colombia were adjusted to reflect compliance with fair-trade criteria. Surprisingly, the results showed that the social risks per functional unit (FU) (1 kg) of the FTC were significantly higher than FTC. This incongruence is caused by the fact that the lower risk values associated with the fair-trade designation are largely offset by its significantly higher economic cost. This is so even though these costs are dedicated to mitigating the risks that are then penalized by the same...
Global NEST International Conference on Environmental Science & Technology
The main objective of this study is to apply the Product Social Impact Assessment (PSIA) handbook... more The main objective of this study is to apply the Product Social Impact Assessment (PSIA) handbook to a case study. The method used to quantify the social impacts is to identify the stakeholders and the social topic, indicators, and then to apply the impact analysis method. Social studies identify the retailing stage as the phase with the greatest social risk in the life cycle followed by the product transformation phase. However, the infeasibility of focusing this study on the multiple companies involved in the commercialization, led the processing stage company to be chosen as the central part of the study. The preliminary evaluation of the social topics of the stakeholders, presents an average of +0.88 points on the level scale (-2 to +2), which positions the company beyond the generally acceptable situation, in continuous improvement.
Revista de fruticultura, 2020
The color and NIR spectrum are key to build an oil estimation model, thus it requires individual ... more The color and NIR spectrum are key to build an oil estimation model, thus it requires individual olives clustering before the Sohlext oil extraction method can be applied. The objective was to analyze an OC estimation model of individual olives, based on cluster of similar color and NIR spectrum in different combination of the first and/or the second season. This study was performed with Chilean Arbequina olives in 2016 and 2017. The descriptor of the cluster consisted of the 3 color channels of c1, c2, c3 color model plus 11 reflectance points between 1710 and 1735 nm of each olive, normalized with the Z-score index. Clusters of similar color and NIR spectrum were formed with the k-means++ algorithm, leaving a sufficient amount of olives to be able to perform the Sohlext analysis of OC, as reference value. The estimation models were based on the Support Vector Machine. The test was carried out with the Leave One-Out Cross Validation in different training-testing combinations. The b...
Global NEST International Conference on Environmental Science & Technology
The aim of this work is to evaluate the environmental performance of fruit production using Life ... more The aim of this work is to evaluate the environmental performance of fruit production using Life Cycle Assessment considering the case study of nectarines produced in the Murcia Region (Southeast Spain). The investigation was carried out according to ISO 14040/14044 using a cradle to grave approach that included three stages: upstream (inputs production and crop establishment), core (agricultural phase, product processing and storage) and downstream (distribution, use phase and waste management). Modelling was carried out using Simapro v.9.1, using the EF 3.0 assessment method and considering 1 kg of fresh fruit as the functional unit. Foreground inventory data was obtained from a 405 ha plot established and run by a local company. Climate change emissions were calculated at 0.76 kg CO2 eq per functional unit. The life cycle stage called downstream is the one that generates the most impacts with 46.9 %, followed by 41.2 % in upstream stage and 11.9 % in core stage. The inputs produc...
Food adulteration is an issue of growing concern, specially delicate throughout early stages of f... more Food adulteration is an issue of growing concern, specially delicate throughout early stages of food processing, regarding the control of the original ingredients included in the process and crossed contaminations. The use of Hyperspectral Imaging (HSI) to detect nuts contamination in powder food products is explored in this work. This study deals with two specific problems of using HSI for the detection of food adulterants: the low dose at which they need to be detected and a high similarity between the spectral NIR signatures of adulterating substances. A chemometric method, issued from a pharmaceutical context, is adapted and tested to detect and identify the presence of different species of oily seeds and nuts in a specific type of commercial wheat flour. The proposed approach was able to detect the presence of 5 kinds of contaminants in percentages from 1 to 5%, but not to identify the contaminant species.
Agrociencia Uruguay, 2015
Los productos mínimamente procesados son alimentos muy atractivos para los consumidores atendiend... more Los productos mínimamente procesados son alimentos muy atractivos para los consumidores atendiendo a sus propiedades nutricionales y a su facilidad de preparación. Sin embargo, la seguridad microbiológica de estos alimentos requiere de especial atención, dado que a lo largo de su proceso no se someten a tratamientos que aseguren la letalidad de los microorganismos. Aparece así la necesidad de dotar a la industria alimentaria en general, y a la de IV gama en particular, de pruebas rápidas para la detección de contaminantes. En este trabajo se presentan los fundamentos de los biosensores y la imagen hiperespectral (IH) y sus aplicaciones en la aportación de información que se pueda correlacionar con la calidad y el estado de frescura de los productos IV gama y de otros alimentos.
Acta Horticulturae, 2018
Bananas are usually harvested in the green-ripe stage and once ripening begins, it is an irrevers... more Bananas are usually harvested in the green-ripe stage and once ripening begins, it is an irreversible process leading banana peel color changes from green to yellow, with brown spots appearing on the yellow color at the end of ripening. The Von Loesecke ripening scale is used by the industry to classify through visual inspection the bananas into one of seven subclasses. Similar scale has been assumed by COPLACA providing to their cooperatives a set of standard images of increasing stages or ripening. This grading process, based on comparison, is very subjective. The sector is demanding an objective procedure for obtaining an indicator able to reflect the real ripening stage. In this paper banana fruit ripening stages were studied along the storage period in ripening chamber (12°C and 80-90% RH) by using hyperspectral imaging technique in the visible and near infrared (400-1000 nm) regions. Two batches of 7 and 14 bananas were monitored. Spectral patterns corresponding to the different ripening stages were distinguished. The main changes in the relative reflectance spectra are located at 680 nm, where an absorption band of the chlorophyll is centered. The scores of the first principal component (94.6% of the explained variance) of the principal component analysis applied on a calibration set of spectra, showed significant differences between the seven maturity classes. Virtual images of banana based on this PCA were generated and spatially characterized in order to classify each individual fruit into one of the COPLACA classes.
Acta Horticulturae, 2018
The evaluation of the cold chain can be faced from product harvesting in the fields up to the she... more The evaluation of the cold chain can be faced from product harvesting in the fields up to the shelf life period in the consumer's houses; while, at the same time, it is possible to assess the performance of the reefers or storage chambers. Many low-costtemperature-sensors have been deployed worldwide, either as WSN or multidistributed RFID loggers, and are commonly used by the industry providing very limited analytics. Recent studies have shown that it is not only the absolute temperature but its derivative, the responsible for relevant changes in fruit quality. Also, the concept of phase analysis, an alternative procedure of analyzing time series, has demonstrated the interest of reproducing the dynamic behavior of a (refrigerated) system; where the reconstruction of the phase space from a time series uses time delays, and the value of the optimal time delays is obtained by heuristics. In this paper we demonstrate the power of such new approach in three different scenarios: local production and distribution of fresh cut vegetables (Chile), the diagnosis of expansion valve malfunction in the refrigeration circuit of warehouses (Spain), and the characterization and supervision of transoceanic transports (Uruguay-Spain/lemons, Uruguay-Rotterdam-Italy/blueberries).
Biosystems Engineering, 2019
Biosystems Engineering, 2017
The increasing need to develop a rapid understanding of plant functional dynamics has led to the ... more The increasing need to develop a rapid understanding of plant functional dynamics has led to the employment of sensor technology for non-destructive assessment of plants. Hyperspectral Imaging (HSI) being an integration of two modalities, imaging and point spectroscopy, is nowadays emerging as a potential tool for rapid, non-destructive and automated close range assessment of plants functional dynamics both in terms of structure and physiology. Firstly, this paper presents an overview of some basic concepts of close range HSI on plants, concerning the plant-light interaction, instrumental setup, and spectral data analysis. Furthermore, the work reviews recent advances of HSI for plant related studies under controlled experimental conditions as well as in natural agricultural settings. Applications are discussed on foliar content estimation, variety identification, growth monitoring, stress and disease-related studies, phenotyping and adoption of HSI in highthroughput phenotyping platforms (HTPPs). Close range HSI is a challenging task and suffers from technical complex
International Journal of Postharvest Technology and Innovation, 2015
Fruit thinning is a widely accepted method of reducing the total amount of fruits on the tree as ... more Fruit thinning is a widely accepted method of reducing the total amount of fruits on the tree as a means of improving fruit quality. However, the thinning operation lacks either a consistent methodology or automated devices capable of monitoring the amount of fruit removed from tree branch. In this study the dynamic response of fruitful branches as fruit clusters were gradually removed from a fresh cut peach branch were simulated and experimentally verified in the Bio-automation Laboratory at the University of California, Davis. Accelerometers were installed on the branch at different positions for experimental verification of the model. Numerical simulations resulting from the application of a finite element method solution to the transient modal analysis problem showed the developed model represented the dynamic behaviour of the branch well. Simulated discrete time signal responses were processed by discrete fast Fourier transforms (FFT). The frequency domain analysis of the signa...
Las microbalanzas de cristal de cuarzo (QCM), son mecanismos piezoelectricos, para transformarlos... more Las microbalanzas de cristal de cuarzo (QCM), son mecanismos piezoelectricos, para transformarlos en sensores quimicos es necesario recubrirlos con una capa de material capaz de capturar las moleculas del ambiente. Cuando una masa es adsorbida sobre la superficie del cristal, la frecuencia de oscilacion cambia en proporcion a la cantidad de masa (Di Natale et al. 1997). La respuesta de los sensores depende de numerosos factores que pueden ser dificiles de controlar, tales como la temperatura y la humedad del gas portador. Todos estos factores producen cambios en la selectividad de los sensores que afectan a la reproducibilidad de las medidas. A pesar de la existencia de numerosos estudios no existe ningun procedimiento establecido para la calibracion de las QCM en relacion con la sensibilidad necesaria en los sensores para el aseguramiento de la calidad en pera o en otras frutas.
Precision agriculture ’21, 2021
Results of previous studies conducted by different researchers have shown that impact techniques ... more Results of previous studies conducted by different researchers have shown that impact techniques can be used to evaluate firmness (Delwiche et al., 1989; Delwiche et al.;1996; Jaren et al., 1992; Ruiz Altisent et al., 1996). To impact the fruit with a small spherical impactor of known mass and radius of curvature and measure the acceleration of the impactor is a technique described by Chen et al. (1985) and used by several researchers for sensing fruit firmness (Jaren et al., 1992; Correa et al.; 1992). The advantages of this method vs. a force sensor that measures the force as a function of time is that the measured impact-acceleration response is independent of the fruit mass and is less sensitive to the variation in the radius of curvature of the fruit (Chen et al., 1996). Ruiz Altisent et al. (1993) developed and used a 50 g impactor with a 19 mm diameter spherical tip, dropping from different height for fruits (apples, pears, avocados, melons, peaches ...). Another impact devic...
Agricultural Engineering International: The CIGR Journal, 2015
Visible-near infrared reflectance spectra are proposed for the characterization of IRMM 481 peanu... more Visible-near infrared reflectance spectra are proposed for the characterization of IRMM 481 peanuts variety in comparison to powder food materials: wheat flour, milk and cocoa. Multidimensional analysis of reflectance spectra of powder samples shows a specific NIR band centred at 1200 nm that identifies peanut compared to the rest of food ingredients, regardless compaction level and temperature. Spectral range of 400-1000 nm is not robust for identification of blanched peanut. The visible range has shown to be reliable for the identification of pre-treatment and processing of unknown commercial peanut samples. A spectral index is proposed based on the combination of three wavelengths around 1200 nm that is 100% robust against pre-treatment (raw or blanched) and roasting (various temperatures and treatment duration).
Se ha desarrollado una nueva version de un dispositivo impactador para obtener un sistema versati... more Se ha desarrollado una nueva version de un dispositivo impactador para obtener un sistema versatil y de facil manejo. La resolucion, la precision y la relacion senal-ruido son mayores en el nuevo sistema que en prototipos anteriores. Se ha realizado un diseno de experimentos con diferentes materiales usando el nuevo y el antiguo impactador para comprobar las mejoras conseguidas.
Global NEST International Conference on Environmental Science & Technology
Quantifying sustainability is a difficult but necessary task to improve our environmental, econom... more Quantifying sustainability is a difficult but necessary task to improve our environmental, economic, and social surroundings. This paper describes an investigation into the use of the Social Hotspot Database (SHDB) to determine the true value of fair-trade certification. The analysis has been carried out on two coffee systems produced in Colombia and consumed in Spain: i) a low-cost generic (GC) and ii) a high-quality organic fair trade certified (FTC). Risk levels in the SHDB for the cultivation sector in Colombia were adjusted to reflect compliance with fair-trade criteria. Surprisingly, the results showed that the social risks per functional unit (FU) (1 kg) of the FTC were significantly higher than FTC. This incongruence is caused by the fact that the lower risk values associated with the fair-trade designation are largely offset by its significantly higher economic cost. This is so even though these costs are dedicated to mitigating the risks that are then penalized by the same...
Global NEST International Conference on Environmental Science & Technology
The main objective of this study is to apply the Product Social Impact Assessment (PSIA) handbook... more The main objective of this study is to apply the Product Social Impact Assessment (PSIA) handbook to a case study. The method used to quantify the social impacts is to identify the stakeholders and the social topic, indicators, and then to apply the impact analysis method. Social studies identify the retailing stage as the phase with the greatest social risk in the life cycle followed by the product transformation phase. However, the infeasibility of focusing this study on the multiple companies involved in the commercialization, led the processing stage company to be chosen as the central part of the study. The preliminary evaluation of the social topics of the stakeholders, presents an average of +0.88 points on the level scale (-2 to +2), which positions the company beyond the generally acceptable situation, in continuous improvement.
Revista de fruticultura, 2020
The color and NIR spectrum are key to build an oil estimation model, thus it requires individual ... more The color and NIR spectrum are key to build an oil estimation model, thus it requires individual olives clustering before the Sohlext oil extraction method can be applied. The objective was to analyze an OC estimation model of individual olives, based on cluster of similar color and NIR spectrum in different combination of the first and/or the second season. This study was performed with Chilean Arbequina olives in 2016 and 2017. The descriptor of the cluster consisted of the 3 color channels of c1, c2, c3 color model plus 11 reflectance points between 1710 and 1735 nm of each olive, normalized with the Z-score index. Clusters of similar color and NIR spectrum were formed with the k-means++ algorithm, leaving a sufficient amount of olives to be able to perform the Sohlext analysis of OC, as reference value. The estimation models were based on the Support Vector Machine. The test was carried out with the Leave One-Out Cross Validation in different training-testing combinations. The b...
Global NEST International Conference on Environmental Science & Technology
The aim of this work is to evaluate the environmental performance of fruit production using Life ... more The aim of this work is to evaluate the environmental performance of fruit production using Life Cycle Assessment considering the case study of nectarines produced in the Murcia Region (Southeast Spain). The investigation was carried out according to ISO 14040/14044 using a cradle to grave approach that included three stages: upstream (inputs production and crop establishment), core (agricultural phase, product processing and storage) and downstream (distribution, use phase and waste management). Modelling was carried out using Simapro v.9.1, using the EF 3.0 assessment method and considering 1 kg of fresh fruit as the functional unit. Foreground inventory data was obtained from a 405 ha plot established and run by a local company. Climate change emissions were calculated at 0.76 kg CO2 eq per functional unit. The life cycle stage called downstream is the one that generates the most impacts with 46.9 %, followed by 41.2 % in upstream stage and 11.9 % in core stage. The inputs produc...
Food adulteration is an issue of growing concern, specially delicate throughout early stages of f... more Food adulteration is an issue of growing concern, specially delicate throughout early stages of food processing, regarding the control of the original ingredients included in the process and crossed contaminations. The use of Hyperspectral Imaging (HSI) to detect nuts contamination in powder food products is explored in this work. This study deals with two specific problems of using HSI for the detection of food adulterants: the low dose at which they need to be detected and a high similarity between the spectral NIR signatures of adulterating substances. A chemometric method, issued from a pharmaceutical context, is adapted and tested to detect and identify the presence of different species of oily seeds and nuts in a specific type of commercial wheat flour. The proposed approach was able to detect the presence of 5 kinds of contaminants in percentages from 1 to 5%, but not to identify the contaminant species.
Agrociencia Uruguay, 2015
Los productos mínimamente procesados son alimentos muy atractivos para los consumidores atendiend... more Los productos mínimamente procesados son alimentos muy atractivos para los consumidores atendiendo a sus propiedades nutricionales y a su facilidad de preparación. Sin embargo, la seguridad microbiológica de estos alimentos requiere de especial atención, dado que a lo largo de su proceso no se someten a tratamientos que aseguren la letalidad de los microorganismos. Aparece así la necesidad de dotar a la industria alimentaria en general, y a la de IV gama en particular, de pruebas rápidas para la detección de contaminantes. En este trabajo se presentan los fundamentos de los biosensores y la imagen hiperespectral (IH) y sus aplicaciones en la aportación de información que se pueda correlacionar con la calidad y el estado de frescura de los productos IV gama y de otros alimentos.
Acta Horticulturae, 2018
Bananas are usually harvested in the green-ripe stage and once ripening begins, it is an irrevers... more Bananas are usually harvested in the green-ripe stage and once ripening begins, it is an irreversible process leading banana peel color changes from green to yellow, with brown spots appearing on the yellow color at the end of ripening. The Von Loesecke ripening scale is used by the industry to classify through visual inspection the bananas into one of seven subclasses. Similar scale has been assumed by COPLACA providing to their cooperatives a set of standard images of increasing stages or ripening. This grading process, based on comparison, is very subjective. The sector is demanding an objective procedure for obtaining an indicator able to reflect the real ripening stage. In this paper banana fruit ripening stages were studied along the storage period in ripening chamber (12°C and 80-90% RH) by using hyperspectral imaging technique in the visible and near infrared (400-1000 nm) regions. Two batches of 7 and 14 bananas were monitored. Spectral patterns corresponding to the different ripening stages were distinguished. The main changes in the relative reflectance spectra are located at 680 nm, where an absorption band of the chlorophyll is centered. The scores of the first principal component (94.6% of the explained variance) of the principal component analysis applied on a calibration set of spectra, showed significant differences between the seven maturity classes. Virtual images of banana based on this PCA were generated and spatially characterized in order to classify each individual fruit into one of the COPLACA classes.
Acta Horticulturae, 2018
The evaluation of the cold chain can be faced from product harvesting in the fields up to the she... more The evaluation of the cold chain can be faced from product harvesting in the fields up to the shelf life period in the consumer's houses; while, at the same time, it is possible to assess the performance of the reefers or storage chambers. Many low-costtemperature-sensors have been deployed worldwide, either as WSN or multidistributed RFID loggers, and are commonly used by the industry providing very limited analytics. Recent studies have shown that it is not only the absolute temperature but its derivative, the responsible for relevant changes in fruit quality. Also, the concept of phase analysis, an alternative procedure of analyzing time series, has demonstrated the interest of reproducing the dynamic behavior of a (refrigerated) system; where the reconstruction of the phase space from a time series uses time delays, and the value of the optimal time delays is obtained by heuristics. In this paper we demonstrate the power of such new approach in three different scenarios: local production and distribution of fresh cut vegetables (Chile), the diagnosis of expansion valve malfunction in the refrigeration circuit of warehouses (Spain), and the characterization and supervision of transoceanic transports (Uruguay-Spain/lemons, Uruguay-Rotterdam-Italy/blueberries).
Biosystems Engineering, 2019
Biosystems Engineering, 2017
The increasing need to develop a rapid understanding of plant functional dynamics has led to the ... more The increasing need to develop a rapid understanding of plant functional dynamics has led to the employment of sensor technology for non-destructive assessment of plants. Hyperspectral Imaging (HSI) being an integration of two modalities, imaging and point spectroscopy, is nowadays emerging as a potential tool for rapid, non-destructive and automated close range assessment of plants functional dynamics both in terms of structure and physiology. Firstly, this paper presents an overview of some basic concepts of close range HSI on plants, concerning the plant-light interaction, instrumental setup, and spectral data analysis. Furthermore, the work reviews recent advances of HSI for plant related studies under controlled experimental conditions as well as in natural agricultural settings. Applications are discussed on foliar content estimation, variety identification, growth monitoring, stress and disease-related studies, phenotyping and adoption of HSI in highthroughput phenotyping platforms (HTPPs). Close range HSI is a challenging task and suffers from technical complex
International Journal of Postharvest Technology and Innovation, 2015
Fruit thinning is a widely accepted method of reducing the total amount of fruits on the tree as ... more Fruit thinning is a widely accepted method of reducing the total amount of fruits on the tree as a means of improving fruit quality. However, the thinning operation lacks either a consistent methodology or automated devices capable of monitoring the amount of fruit removed from tree branch. In this study the dynamic response of fruitful branches as fruit clusters were gradually removed from a fresh cut peach branch were simulated and experimentally verified in the Bio-automation Laboratory at the University of California, Davis. Accelerometers were installed on the branch at different positions for experimental verification of the model. Numerical simulations resulting from the application of a finite element method solution to the transient modal analysis problem showed the developed model represented the dynamic behaviour of the branch well. Simulated discrete time signal responses were processed by discrete fast Fourier transforms (FFT). The frequency domain analysis of the signa...
Las microbalanzas de cristal de cuarzo (QCM), son mecanismos piezoelectricos, para transformarlos... more Las microbalanzas de cristal de cuarzo (QCM), son mecanismos piezoelectricos, para transformarlos en sensores quimicos es necesario recubrirlos con una capa de material capaz de capturar las moleculas del ambiente. Cuando una masa es adsorbida sobre la superficie del cristal, la frecuencia de oscilacion cambia en proporcion a la cantidad de masa (Di Natale et al. 1997). La respuesta de los sensores depende de numerosos factores que pueden ser dificiles de controlar, tales como la temperatura y la humedad del gas portador. Todos estos factores producen cambios en la selectividad de los sensores que afectan a la reproducibilidad de las medidas. A pesar de la existencia de numerosos estudios no existe ningun procedimiento establecido para la calibracion de las QCM en relacion con la sensibilidad necesaria en los sensores para el aseguramiento de la calidad en pera o en otras frutas.
Precision agriculture ’21, 2021
Results of previous studies conducted by different researchers have shown that impact techniques ... more Results of previous studies conducted by different researchers have shown that impact techniques can be used to evaluate firmness (Delwiche et al., 1989; Delwiche et al.;1996; Jaren et al., 1992; Ruiz Altisent et al., 1996). To impact the fruit with a small spherical impactor of known mass and radius of curvature and measure the acceleration of the impactor is a technique described by Chen et al. (1985) and used by several researchers for sensing fruit firmness (Jaren et al., 1992; Correa et al.; 1992). The advantages of this method vs. a force sensor that measures the force as a function of time is that the measured impact-acceleration response is independent of the fruit mass and is less sensitive to the variation in the radius of curvature of the fruit (Chen et al., 1996). Ruiz Altisent et al. (1993) developed and used a 50 g impactor with a 19 mm diameter spherical tip, dropping from different height for fruits (apples, pears, avocados, melons, peaches ...). Another impact devic...
Agricultural Engineering International: The CIGR Journal, 2015
Visible-near infrared reflectance spectra are proposed for the characterization of IRMM 481 peanu... more Visible-near infrared reflectance spectra are proposed for the characterization of IRMM 481 peanuts variety in comparison to powder food materials: wheat flour, milk and cocoa. Multidimensional analysis of reflectance spectra of powder samples shows a specific NIR band centred at 1200 nm that identifies peanut compared to the rest of food ingredients, regardless compaction level and temperature. Spectral range of 400-1000 nm is not robust for identification of blanched peanut. The visible range has shown to be reliable for the identification of pre-treatment and processing of unknown commercial peanut samples. A spectral index is proposed based on the combination of three wavelengths around 1200 nm that is 100% robust against pre-treatment (raw or blanched) and roasting (various temperatures and treatment duration).
Se ha desarrollado una nueva version de un dispositivo impactador para obtener un sistema versati... more Se ha desarrollado una nueva version de un dispositivo impactador para obtener un sistema versatil y de facil manejo. La resolucion, la precision y la relacion senal-ruido son mayores en el nuevo sistema que en prototipos anteriores. Se ha realizado un diseno de experimentos con diferentes materiales usando el nuevo y el antiguo impactador para comprobar las mejoras conseguidas.