32 research outputs found
Optimization of chlorine sanitation to preserve quality of minimally processed Vicia fabe seeds
[SPA] Se ensayó diversas concentraciones de NaClO en el agua de lavado para preservar la calidad de semillas de haba mínimamente procesadas en fresco durante 7 días a 3ºC. Se lavó con agua de la red (testigo) y con diferentes concentraciones de hipoclorito (50 y 100 ppm) añadiendo en algunos casos ácido cítrico (200 ppm), pudiendo actuar como agente antipardeante o como potenciador de la acción del cloro. La duración de los tratamientos fue de 2 minutos y el tiempo de enjugado de 1 minuto, así como, la temperatura del agua fue en todos los casos de 5ºC. Debido a un mal diseño del envase, la AM generada en el interior no fue la adecuada, lo cual perjudicó la calidad de las habas. Sin embargo la calidad microbiológica de las mismas fue aceptable 7 días a 3ºC. Se necesitará optimizar primero el envase para sacar las conclusiones pertinentes en futuras experiencias.
[ENG] Several NaClO concentrations in the wash water was tested to preserve the quality of minimally processed Vicia faba seeds stored for 7 days at 3 °C. Washing treatments were: tap water (control) and with several NaClO concentrations (50 and 100 ppm) adding in some cases citric acid (200 ppm) that may act as antibrowning agent or as an enhancer of the chlorine action. Samples were washed for 2 minutes and rinsed for 1 minute. The water temperature in all cases was 5 °C. Due to a wrong package design, the MA generated was inadequate, which induced quality deterioration of the seeds. However, the microbiological quality was still acceptable after 7 days at 3ºC. In further experiments the packaging will be needed to be optimized before drawing appropriate conclusions about NaClO dose optimization.Los autores agradecen a Frutas Esparza S.A. y al proyecto europeo EUROLEGUME FP7-BBBE.2013.1.2-02 la financiación recibida
Efecto de agentes desinfectantes alternativos al hipoclorito sódico en la calidad de habas mínimamente procesadas en fresco
En la búsqueda de alternativas al habitual empleo en la desinfección del hipoclorito
sódico durante el procesado mínimo de los productos hortofrutícolas, se recurre otros
agentes antimicrobianos, que además de inhibir la contaminación microbiológica,
sean capaces de actuar como agentes antipardeantes (ácido oxálico, dióxido de cloro,
ácido ascóbico y 4‐hexilresorcinol), para inhibir en todo lo posible el pardeamiento
enzimático que sucede sobre la superficie de las semillas de las habas mínimamente
procesadas al finalizar su vida comercial. Este defecto provoca que las semillas sean
no comercializables por su aspecto visual aunque la calidad microbiana sea adecuada.
Para ellos se eligió una variedad de haba y una temperatura de vida comercial de 5ºC
durante 8 días. De todos los tratamientos estudiados, el dióxido de cloro y el ácido
ascórbico fueron los que mejores resultados obtuvieron frente a los demás
tratamientos, controlando el pardeamiento.A Frutas Esparza S.A. por la financiación
recibida
Antibrowning washing agents effect to preserve quality of minimally processed Vicia faba seeds
[SPA] Se ensayaron diversos agentes antipardeantes (ácido ascórbico, ácido peroxiacético y ácido etilen diamino tetra acético-EDTA) para prevenir el pardeamiento en semillas de haba mínimamente procesadas en fresco. En primer lugar, se aplicaron los diferentes antipardeantes descritos en una línea de procesado industrial, lavando 2 min a 5 °C y enjuagando 1 min, si era necesario, en combinación con 2 films a base de polipropileno (PP) para generar una atmósfera modificada (AM) durante 10 días a 4±1 °C. Dichos films fueron PP biorientado -BOPP- y PPlus®. Tras los resultados obtenidos, en un segundo ensayo, realizado en la UPCT, se usó un único film (BOPP) durante 9 días a 4±1 °C. En todos los casos la temperatura del agua de lavado fueron 5 °C. En el ensayo a escala industrial, la AM no fue adecuada, perjudicando la calidad de las habas. Sin embargo, en condiciones controladas en la UPCT existió una estabilización de la atmósfera y se mantuvo la calidad de las habas. Se necesitará profundizar en el control de parámetros a nivel industrial.
[ENG] Several antibrowning agents (ascorbic acid, peroxyacetic acid and ethylene diamine tetra acetic-EDTA) were tested to prevent browning in the washing step of minimally processed Vicia faba seeds. In a first test, antibrowning agents were applied in an industrial process by washing for 2 min and rinsed for 1 min, if necessary, in combination with 2 polypropylene (PP) films to generate a modified atmosphere (MA) during 10 days at 4±1 °C. These films were bi-axially orientated PP -BOPP- and PPlus®. Considering the results of this test, a second test was made in the UPCT facilities. An OPP film was used for packaging after washing with the antibrowning agents during a shelf life of 9 days at 4±1 °C. The water temperature in all cases was 5 °C. At industrial scale, the MA generated was inadequate, which induced quality deterioration of the seeds. However under controlled conditions in the UPCT facilities, the atmosphere stabilization was enough to preserve the quality. It will be needed to control the parameters at industrial scale.Los autores agradecen a Frutas Esparza S.A. y al proyecto europeo EUROLEGUME FP7-BBBE.2013.1.2-02 la financiación recibid
Método industrial para el procesado mínimo en fresco de habas y de guisantes y planta de procesado
Número de publicación: 2 412 959
Número de solicitud: 201330811Planta y método de procesado mínimo en fresco de habas y de guisantes que comprende las etapas y medios para la prerrefrigeración (102) de las vainas; el prelavado (103) en agua de las vainas antes de extraer la semilla; el transporte de las semillas extraídas (1) hasta una zona limpia (200) a través de un conducto con transporte por agua; el lavado (3) de las semillas con agua, desinfectantes y aditivos; el enjuagado (3) de las semillas; el escurrido y secado (4) de las semillas por aire frío forzado; y el envasado de las semillas.Universidad Politécnica de Cartagen
Continuous and Conventional Microwave Heating Effects on the Antioxidant Capacity of Tomato Juice
Thermal processing extends the shelf life of fruits and vegetables by inactivating
microorganisms and enzymes. The efficacy of heating depends on the properties of
the food and mainly on the processing parameters. The microwave (MW) oven offers
several advantages for keeping overall quality and safety of the foods products. A
continuous MW oven is a new tool which can make the cooking process of plant
products shorter. The present work evaluates the effect of a new industrial continuous
MW oven at different heating powers (750, 900 and 1050 W) and times (from 120 to
420 s) on the antioxidant capacity of tomato juice. This treatment was compared to
other tomato juice heated in a conventional MW oven (750 and 900 during 60 to 150
s). As control non heated juice was used. The results showed that the antioxidant
capacity was lowered by the heating. In general, as longer the duration and higher the
power applied the lower antioxidant capacity was found. However, a moderate high
power dose (900 W) combined with shorter duration (120 or 150 s) kept better the
antioxidant capacity than low power MW dose (750 W) combined with high treatment
duration (360 or 420 s). At similar doses (time/power) the industrial MW provided a
slightly lower antioxidant capacity than conventional MW. As main conclusion, when
comparing the efficacy of the continuous MW oven versus the conventional one no
advantage for keeping the antioxidant capacity of tomato juice was found.Thanks are due to Instituto de Biotecnología
Vegetal (IBV‐UPCT) for providing some of the
equipments. This work was financially
supported by the Postharvest and Refrigeration
Group of the Universidad Politécnica de
Cartagena
Continuous microwave heating effects on quality of carrot and tomato smoothie
The effect of conventional and microwave pasteurization on the lycopene and β-carotene content and on the physicochemical quality attributes (TSS, pH, TA and color) of pasteurized orange smoothie were evaluated. The smoothie was elaborated with tomato, carrot, pumpkin, lemon juice, mineral water and marine salt. The conventional pasteurization (CP) was made by mean of a semi-industrial thermomix, while for microwave pasteurization (MWP) an innovative semi-industrial continuous microwave oven was used. After both pasteurization methods no significant changes in TSS, pH and TA were found while the carotenoids content was enhanced. MWP provided the highest lycopene and β-carotene content, showing MW equipment as a tool to pasteurize and improve the bioavailability of carotenoids of the smoothie.Thanks are due to Instituto de Biotecnología
Vegetal (IBV-UPCT) for providing MW
equipment. This work was financially supported
by Spanish Ministry of Economy and
competitiveness MINECO (AGL2013-48830-C2-1-
R) and FEDER
Semi-industrial microwave treatments positively affect the quality of orange colored smoothies
Thermal processing extends the shelf life of fruit and vegetables products by inactivating microorganisms and enzymes. The effect of a pasteurization (P) treatment, 90 °C ± 2 ºC for 35 s, provided by continuous semi-industrial microwave (MW) under different con-ditions (high power/short time and low power/long time) or conventional pasteurization (CP) on orange-colored smoothies and their changes throughout 45 days of storage at 5 °C were investigated. Results indicated that vitamin C and antioxidant capacity (FRAP) in CP decreased dramatically in comparison with the unheated and MWP smoothies. On the contrary, all heating treatments increased the contents of total phenolic compounds (TPC) and carotenoids. Based on the sensory quality and microbial counts, the shelf life of all those heated smoothies reached 45 days. No Listeria monocytogenes growth was found and all microbial counts were below the European legal limits. MWP as compared to the CP method led to a greater reduction of mesophilic bacteria after 45 days at 5 °C (3.7 log cfu g-1 for CP and 1.6 log cfu g-1 for MWP). When highest power and shortest time MWP treatments were used (3,600 W for 93 s), FRAP and vitamin C were better preserved.This work was financially supported by MINECO-FEDER (AGL2013-48830-C2-1-R). Thanks are due to Instituto de Biotecnología Vegetal (IBV-UPCT) for providing some of the equipmen
Continuous microwave pasteurization of a vegetable smoothie improves its physical quality and hinders detrimental enzyme activity
The effect of a pasteurization treatment at 90 2 C for 35 s provided by continuous microwave under different
doses (low power/long time and high power/short time) or conventional pasteurization on the quality of
orange-colored smoothies and their changes throughout 45 days of storage at 5 C was investigated.
A better color retention of the microwave pasteurization- treated smoothie using high power/short time
than in conventionally processed sample was evidenced by the stability of the hue angle. The continuous
microwave heating increased the viscosity of the smoothie more than the conventional pasteurization in
comparison with non-treated samples. Lower residual enzyme activities from peroxidase, pectin methylesterase
and polygalacturonase were obtained under microwave heating, specifically due to the use of higher
power/shorter time. For this kind of smoothie, polygalacturonase was the more thermo-resistant enzyme and
could be used as an indicator of pasteurization efficiency. The use of a continuous semi-industrial microwave
using higher power and shorter time, such as 1600 W/206 s and 3600 W/93 s, resulted in better quality
smoothies and greater enzyme reduction than conventional thermal treatment.The author(s) disclosed receipt of the following financial support
for the research, authorship, and/or publication of this
article: The authors would like to thank the Spanish Ministry
of Economy and Competitiveness and the European Regional
Development Fund (MINECO-FEDER, AGL2013-48830-
C2-1-R) for financial suppor
Microwave flow and conventional heating effects on the physicochemical 1 properties, bioactive compounds and enzymatic activity of tomato puree
BACKGROUND
Thermal processing causes a number of undesirable changes in physicochemical and bioactive properties of tomato products. Microwave (MW) technology is an emergent thermal industrial process that offers a rapid and uniform heating, high energy efficiency and high overall quality of the final product. The main quality changes of tomato puree after pasteurization at 96 ± 2 °C for 35 s, provided by a semi-industrial continuous microwave oven (MWP) under different doses (low power/long time to high power/short time) or by conventional method (CP) were studied.
RESULTS
All heat treatments reduced colour quality, total antioxidant capacity and vitamin C, with a greater reduction in CP than in MWP. On the other hand, use of an MWP, in particular high power/short time (1900 W/180 s, 2700 W/160 s and 3150 W/150 s) enhanced the viscosity and lycopene extraction and decreased the enzyme residual activity better than with CP samples. For tomato puree, polygalacturonase was the more thermo-resistant enzyme, and could be used as an indicator of pasteurization efficiency.
CONCLUSION
MWP was an excellent pasteurization technique that provided tomato puree with improved nutritional quality, reducing process times compared to the standard pasteurization process. © 2016 Society of Chemical IndustryThis work was financially supported by MINECO-FEDER (AGL2013-48830-C2-1-R)
A new algorithm for rhythm discrimination in cardioverter defibrillators based on the initial voltage changes of the ventricular electrogram
Aims: Ventricular activation onset is faster in supraventricular beats than in ventricular rhythms. The aim of this study was to evaluate a criterion to differentiate supraventricular (SVT) from ventricular tachycardia (VT) based on the analysis of the initial voltage changes in ICD-stored morphology electrograms. Methods. Far field ICD-stored EGMs were obtained from 68 VT and 38 SVT episodes in 16 patients. The first EGM peak was detected, three consecutive time epochs were defined within the preceding 80 ms window and the voltage changes with respect to a sinus template were analysed during each time period and combined into a single parameter for rhythm discrimination. Results. The algorithm was tested in an independent validation group of 442 VT and 97 SVT spontaneous episodes obtained from 22 patients with a dual chamber ICD. The area under the receiver-operator characteristics (ROC) curve indicated that the arrhythmia separability with this method was 0.95 (tolerance interval: 0.85-0.99) and 0.98 (0.87-0.99) for the control and validation groups respectively. A specificity of 0.91 was obtained at 95% sensitivity in the validation group. Conclusion. The analysis of voltage changes during the initial ventricular activation process is feasible using the far field stored electrograms of an ICD system and yields a high sensitivity and specificity for arrhythmia discrimination