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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Factors associated with variability in the growth of lucerne (Medicago sativa L)

Nikandrow, Alexander. January 1979 (has links) (PDF)
No description available.
2

Factors associated with variability in the growth of lucerne (Medicago sativa L)

Nikandrow, Alexander January 1979 (has links)
viii, 329 leaves : graphs, tables, photos, (1 col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Pathology, 1981
3

Factors associated with variability in the growth of lucerne (Medicago sativa L)

Nikandrow, Alexander January 1979 (has links)
viii, 329 leaves : graphs, tables, photos, (1 col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Pathology, 1981
4

Factors associated with variability in the growth of lucerne (Medicago sativa L).

Nikandrow, Alexander. January 1979 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Department of Plant Pathology, 1981.
5

Porovnání suchovzdornosti a mrazuvzdornosti vybraných odrůd vojtěšky seté (Medicago sativa L.) z tuzemského a zahraničního šlechtění / Comparison of drought and frost resistence of selected varieties of \kur{Medicago sativa} L. from domestic and foreign breeding

HLAVÁČKOVÁ, Petra January 2011 (has links)
The aim was comparison of drought and frost resistence of selected varieties of Medicago sativa L. from domestic and foreign. The evaluation was performed by a series of laboratory experiments and observations in two replications in 2009 ? 2010. The results were evaluated as the most resistant varieties to frost variety from the Czech Republic and Slovakia. Namely variety Magda Litava, Tisa and Synthesis. As the least resistant varieties have been evaluated varieties from the warm coastal areas. Most resistant varieties to water deficit during vegetation varieties were evaluated Magda, Comete, Europe and Camilla. The climatic conditions of the Czech Republic would be most appropriate, according to the results observed varieties of Magda. It has high resistance to frost and has good results in drought. Other good varieties from Czech Republic are Pálava and Camilla. Of the foreign varieties would be best to use a French variety of Como, Europe and the Dutch variety of Capri. These varieties have good resistance to frost and high drought. The whole problem of drought and frost resistance of alfalfa is not yet explored, it would be appropriate, the results obtained confirmed by further research.
6

Aplicación de sanitizantes en brotes de alfalfa (Medicago sativa L.) conservados bajo atmósfera modificada

Maureira Espinosa, Yenifert January 2012 (has links)
Memoria para optar al título profesional de Ingeniero Agrónomo Mención Agroindustria / El objetivo de este estudio fue evaluar el efecto de distintos sanitizantes como hipoclorito de sodio (NaClO 100 mg L-1), dióxido de cloro (ClO2 5 y 10 mg L-1), ácido peroxiacético (APA 50 y 90 mg L-1) y clorito de sodio acidificado (CSA 250 y 500 mg L-1) sobre la carga microbiana y calidad sensorial en brotes de alfalfa envasados en atmósfera modificada pasiva conservados a 5º C por 7 días. En dos ensayos independientes se emplearon las mismas dosis de sanitizantes, pero diferentes bolsas con diferente permeabilidad a los gases. Los parámetros evaluados fueron respiración, concentración de gases en el interior de las bolsas, color, carga microbiana y calidad sensorial. El uso de bolsas de baja permeabilidad utilizadas en el Ensayo I, junto con las dosis de sanitizantes no fue efectivo para mantener la calidad sensorial de los brotes de alfalfa. Las concentraciones alcanzadas al interior de las bolsas fueron de 18,2 a 27% de CO2 y 1 a 1,2% de O2 tras 7 días. En todos los tratamientos se obtuvo una reducción de los recuentos en aerobios mesófilos, psicrófilos y enterobacterias al utilizar los distintos sanitizantes. El CSA 250 y 500 presentaron los recuentos más bajos, sin embargo afectaron negativamente el color, y calidad sensorial de los brotes. En el Ensayo II, las concentraciones al interior de las bolsas fueron de 2,7 a 4,1% de CO2 y 3,6 a 6,7% de O2 y al igual que el Ensayo I, el CSA 500 fue el sanitizante que presentó los menores recuentos en aerobios mesófilos, enterobacterias y psicrófilos con 4,6, 4,8 y 5,5 log ufc g-1, respectivamente, seguido por CSA 250 con 5,4, 5,3 y 5,7 log ufc g-1, respectivamente, sin afectar las características sensoriales. En ambos ensayos fue el NaClO (Bp) el tratamiento que registró recuentos más altos en mesófilos y enterobacterias, lo que confirmaría que el envasado en AM mantiene mejor la calidad microbiológica que el envasado en contacto con el aire. Por tanto los brotes de alfalfa lavados con CSA 250 y 500 en combinación con un envasado en atmósfera modificada diminuyeron la carga microbiana sin afectar la calidad sensorial, manteniéndose dentro de la media aceptable durante los 7 días a 5º C. / The objective of this study was to evaluate the effect of different sanitizers as sodium hypochlorite (NaClO 100 mg L -1 ), chlorine dioxide (ClO2 5 and 10 mg L -1 ), peroxyacetic acid (APA 50 and 90 mg L -1 ) and acidified sodium chlorite (ASC 250 and 500 mg L -1 ) on the microbial and sensory quality in packaged alfalfa sprouts passive modified atmosphere maintained at 5° C for 7 days. In two independent assays the same doses of sanitizers, and bags with different permeability to gases were used. The parameters evaluated were breathing, gas concentration inside the bags, color, microbial load and sensory quality. The use of low permeability bags used in the assay I, along with doses of sanitizers was not effective to maintain the sensory quality of alfalfa sprouts. Concentrations achieved within the bags were 18.2 to 27% CO2 and 1 to 1.2% O2 after 7 days. In all treatments a reduction in aerobic plate counts, mesofilos, psychrofiles and enterobacteriaceae using different sanitizers was observed. The CSA 250 and 500 showed the lowest counts, but affected negatively the color and sensory quality of sprouts. In assay II, the concentrations inside the bags were from 2.7 to 4.1% CO2 and 3.6 to 6.7% O2 and just that the assay I, CSA 500 was the sanitizer that presented the lower aerobic plate counts, enterobacteriaceae and psychrophiles with 4.6, 4.8 and 5.5 log CFU g -1 respectively, followed by CSA 250 with 5.4, 5.3 and 5.7 log cfu g -1 respectively, without affecting the sensory characteristics. In both assays was the NaClO (BP) treatment to higher counts recorded plate and Enterobacteriaceae, which would confirm that the packaging AM maintains the microbiological quality better than the packaging in contact with air. So alfalfa sprouts washed with CSA 250 and 500 in combination with modified atmosphere packaging decreases the microbial load without affecting the sensory quality, while remaining within acceptable average for 7 days at 5º C.
7

Nutritive value of Cassia sturtii, Sutherlandia microphylla and Medicago sativa for sheep

Tucker, Jacqueline 12 February 2013 (has links)
The aim of this study was to assess the potential nutritive value for sheep, of two drought tolerant leguminous shrubs (Cassia sturtii and Sutherlandia microphylla) in terms of chemical composition, degradation parameters, digestibility, rumen fermentation parameters, intake, microbial nitrogen synthesis and nitrogen balance as well as the rumen kinetics when compared to that of Medicago sativa. The crude ash concentration of all three forages differs, with S. microphylla and C. sturtii lower than M. sativa. M. sativa has a crude ash concentration almost twice the amount of both S. microphylla and C. sturtii. Wilcock et al., (2004) reported ash values for C. sturtii stems and leaves of 53 and 73 g/kg and that of S. microphylla at 25 and 64g/kg respectively. Values for C. sturtii are lower while those of S. microphylla compare well to the average of the whole plant. The mean CP and CF concentration differed between species with C. sturtii having the lowest CP and M. sativa the highest. S. microphylla had the highest CF while M. sativa had the lowest. The NDF and ADF levels of the samples varied between all three species with S. microphylla being the highest and M. sativa the lowest. Values for C. sturtii were in between those of the two other forages. The ADL concentration of S. microphylla was higher than both C. sturtii and M. sativa. The degree of lignification in C. sturtii was high (23.8% of NDF was ADL). The degree of lignification of S. microphylla was 26.8%, which is higher than that of C. sturtii, while M. sativa is the same as C. sturtii. The calcium concentrations of C. sturtii and M. sativa are similar and have a higher concentration than S. microphylla. M. sativa and C. sturtii had a higher phosphorus concentration than S. microphylla. With respect to magnesium (Mg), C. sturtii and M. sativa have a similar composition while S. microphylla has a lower concentration. The iron concentration of all three plants differs, with M. sativa having the lowest concentration and C. sturtii the highest. The copper concentrations in M. sativa and C. sturtii were similar, while that of S. microphylla was slightly lower. The zinc concentrations in M. sativa and C. sturtii were similar, while that of S. microphylla was slightly higher. Manganese concentration of all three species differs, with C sturtii being the lowest and S. microphylla the highest. The plants from this trial were analysed for selenium but none or very insignificant levels were found and were not worth reporting. The apparent DM digestibility of S. microphylla is significantly lower than M. sativa while it did not differ significantly from C. sturtii. C. sturtii did not differ significantly from both M. sativa and S. microphylla. The CP digestibility of all three species did not differ significantly, however that of M. sativa is numerically higher. With regards to the apparent NDF digestibility, C. sturtii and S. microphylla differ significantly to M. sativa with lower NDF digestibility values. The apparent OM digestibility followed the same trend as that of apparent DM digestibility. The average intake was very different between species, with C. sturtii being the lowest and M. sativa the highest. The animals consuming either C. sturtii or S. microphylla tended to lose body weight during the experimental period, while those eating M. sativa gained body weight. Voluntary intake parameters of C. sturtii and S. microphylla were lower and differed significantly between M. sativa. The DM intake of M. sativa was higher than both C. sturtii and S. microphylla. The ME was the highest for M. sativa while S. microphylla was significantly different and had the lowest value. C. sturtii had an ME value similar to both M. sativa and S. microphylla. The ME intake of S. microphylla was 2.89 MJ/day compared to that of M. sativa of 8.57 MJ/day. Rumen NH3-N concentrations of C. sturtii were the lowest and differed significantly from S. microphylla and M. sativa. Sheep receiving C. sturtii had the lowest total rumen VFA concentration and was significantly different from M. sativa which had the highest value. S. microphylla had a similar total VFA concentration to both C. sturtii and M. sativa. C. sturtii had the lowest proportion of acetate but did not differ significantly compared to S. microphylla, while both were significantly different to M. sativa, which had the highest value. The propionate concentration for all three forages did not differ significantly. S. microphylla had the highest fibre concentration, therefore leading to higher acetate concentrations than C. sturtii but not higher than M. sativa, suggesting the fibre of S. microphylla is less digestible. This is supported by the low apparent NDF digestibility for S. microphylla. Nitrogen intake was highest for M. sativa and was significantly different from C. sturtii and S. microphylla. The same trend followed for faecal and urinary nitrogen output as well as nitrogen retention. The nitrogen retention for all species was positive with C. sturtii being the lowest. These values compare well to the CP content of the three forages with C. sturtii the lowest and M. sativa the highest concentration. The daily urinary allantoin elimination did not differ between C. sturtii and S. microphylla but was significantly different and higher for M. sativa. The amount of microbial nitrogen supplied to the animal (g/day and g/kg DOMI) followed the same trend as allantoin. M. sativa had significantly higher a-values (soluble fraction) for both DM and NDF degradation compared to the two shrub species at a rate constant of 0.02/h. C. sturtii had a higher b-value (potentially degradable fraction) for DM degradation compared to S. microphylla which shows that S. microphylla DM component was most readily soluble. For NDF, however, the b-values didn’t differ among the species. Species had also no effect on the c-values (rate of degradation of the potentially degradable fraction b) of both DM and NDF. Therefore all species appear to have a similar potential source of energy for use by micro-organisms in the rumen. Effective DM degradability of C. sturtii and S. microphylla was similar while that of M. sativa was significantly higher. The effective NDF degradability for C. sturtii and S. microphylla was similar and M. sativa again had a significantly higher NDF degradability. The rumen DM degradability for all three species showed a similar trend but much higher values than the apparent DM digestibility. The rumen NDF degradability values were almost identical to those reported for apparent NDF digestibility. The rate of intake and rate of digestion for C. sturtii and S. microphylla did not differ significantly, while that of M. sativa was the highest and significantly different. The rate of passage for all three species was similar. The percent NDF digested in the rumen differed significantly between all three species with C. sturtii being the lowest and M. sativa the highest. The percent NDF passing from the rumen also differed significantly between all three species, however this time C. sturtii being the highest and M. sativa the lowest, which corresponds well to the values for NDF digested in the rumen. It is concluded that C. sturtii and S. microphylla are of a slightly lower nutritional value for sheep than M. sativa. If these two leguminous fodder species were to be used as maintenance feed, some other supporting source of energy would need to be supplied in order for these sheep to be maintained over a long period. The negative effect of all fibre related parameters (CF, NDF, ADF and ADL) in C. sturtii and S. microphylla, reduced digestibility as well as intake, leading to a forage of lower nutrient value as compared to M. sativa. The effect of anti-nutritional factors present in C. sturtii and S. microphylla on the digestibility of forages and nutrient contribution from forages needs to be studied to determine if these play a role in reducing the nutritional value. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2013. / Animal and Wildlife Sciences / unrestricted
8

New challenges for lucerne in southern Australian farming systems : identifying and breeding diverse lucerne germplasm to match these requirements.

Humphries, Alan Wayne January 2008 (has links)
Lucerne is a deep-rooted perennial pasture that is promoted to land managers in southern Australia to mitigate the effects of dryland salinity, a problem of national significance caused by the replacement of native trees and shrubs with annual crops and pastures. In recent years, the acceptance of climate change has provided further rationale for increasing the use of perennial legumes in our farming systems. Perennial legumes have a role in offsetting C02 emissions by sequestering C and N in soil, and provide new, resilient options for future farming in a warmer and more variable climate. This research has focused on evaluating the diverse range of germplasm found in lucerne (Medicago sativa spp.) for a range of attributes in order to determine its compatibility with existing and future farming systems in southern Australia. Regional field evaluation at 8 sites in southern Australia showed that lucerne is a broadly adapted and robust plant. After 3 years, plant density ranged from 2-55 plants / m2 with differences in persistence attributed to tolerance to a combination of stresses including soil acidity, saline and sodic subsoils, drought conditions and persistent heavy grazing. Highly winter-active lucerne (class 9-10) was confirmed to be the most suitable group for short phase rotations in southern Australia, providing grazing is well managed. This germplasm was less persistent than other winter activity groups, but produces more total herbage yield in environments with winter dominant rainfall patterns. Highly winter-active lucerne has poor persistence under continuous grazing, but this may aid in its removal when used in rotation with crops. Winteractive germplasm (class 6-8) was more grazing tolerant and persistent, making it the most suitable group for longer phase rotations (>4 years), or where more flexible grazing management practices are required (i.e. 35 days grazing followed by 35 days recovery). Individual grazing tolerant plants from this group were selected and randomly inter-mated to form new breeder’s lines in the development of a grazing tolerant cultivar. For the first time, the high water-use of a farming system involving wheat overcropped into lucerne is presented. Lucerne over-cropped with wheat used an additional 43-88 mm of water in comparison to continuous wheat at Roseworthy and Katanning respectively. Over-cropping reduced wheat yield by 13-63%, but it can be more efficient in terms of land area to grow lucerne and wheat as a mixture than on separate parcels of land. Very winter-dormant lucerne (class 1-2) appears to be less competitive with winter cereal crops during wheat establishment. It may also be possible to reduce lucerne’s competition with wheat at the critical stage of anthesis, with low spring yielding lucerne varieties identified in this research (SA37908). This group of plants provides excellent potential for the development of high water-use farming systems because they are grazing tolerant and persistent, and have summer forage production and sub-soil water extraction rates that are equivalent to winter active lucerne. The research has been used to identify the perfect ideotype for lucerne in phase farming and over-cropping systems, which can be used to set targets in future breeding programs. The research also highlights current opportunities for the integration of lucerne into southern Australian farming systems to help curb the spread of dryland salinity and reduce the impact of climate change. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1344608 / Thesis (Ph.D.) - University of Adelaide, School of Agriculture, Food and Wine, 2008
9

Efecto de la temperatura de almacenamiento sobre la tasa respiratoria y calidad de germinados de alfalfa mínimamente procesados en fresco / Effect of storage temperature on the respiratory activity and quality in minimally processed alfalfa sprouts

Flores Pino, Paulina Alondra January 2013 (has links)
Memoria para optar al título profesional de: Ingeniero Agrónomo Mención: Agroindustria / El objetivo de este estudio fue evaluar el efecto de distintas temperaturas de almacenamiento (0, 5 y 8 ºC), sobre la tasa respiratoria y calidad sensorial de germinados de alfalfa (Medicago sativa L.) mínimamente procesados. Estos fueron lavados con agua potable a 5 ºC, secados y envasados en tarrinas de polietileno (PE), posteriormente fueron almacenados durante 6 y 8 días (95% de humedad relativa). Los parámetros medidos fueron: tasa respiratoria, color, sólidos solubles totales, acidez titulable y calidad sensorial. En ambos ensayos se observó una tendencia a la disminución de la tasa respiratoria a lo largo del almacenamiento, para todos los tratamientos. El tratamiento 0 ºC, presentó tasas significativamente más bajas en comparación a los otros dos tratamientos, con valores de 13,9 a 27,6 mg CO2 · kg-1 · h-1 en el ensayo 1 y de 19,2 a 39,8 mg CO2 · kg-1 · h-1 en el ensayo 2. El tratamiento 5 ºC registró tasas entre 23,1 y 45,1 mg CO2 · kg-1 · h-1 y 21,4 a 58,6 mg CO2 · kg-1 · h-1 en el ensayo 1 y 2 respectivamente. El tratamiento 8 ºC, presentó tasas significativamente mayores registrándose rangos entre 30,2 y 47,0 mg CO2 · kg-1 · h-1 en el ensayo 1 y 38,1 a 88,2 mg CO2 · kg-1 · h-1 en el ensayo 2. Con respecto a la evolución del color, en el ensayo 1 el tratamiento 0 ºC presentó menores valores de croma y tono, es decir, se observó un producto menos pardeado, con respecto a los otros tratamientos, registrándose valores promedio de croma en un rango 11,6 a 12,9 y tono entre 94 a 93,4. En el ensayo 2, sólo se observaron menores valores para el parámetro de tono para el mismo tratamiento, registrándose valores promedio entre 93,5 y 92,9. Se observaron aumentos significativos en la acidez a lo largo de los días de almacenamiento para los tres tratamientos, en el ensayo 1. En cuanto a la evolución de la calidad sensorial, se observaron diferencias en el ensayo 1, en los parámetros apariencia e intensidad de color, el tratamiento mejor evaluado fue el almacenado a 8 ºC. En el ensayo 2, el tratamiento 8 ºC fue el mejor evaluado en cuanto a apariencia, en cambio, fue el peor evaluado en cuanto a presencia de olores extraños. / The aim of this study was to evaluate the effect of different storage temperatures (0, 5 and 8 °C) on respiratory rate and sensory quality of alfalfa sprouts (Medicago sativa L.) minimally processed. The sprouts were washed with water at 5 °C, dried and packed in polyethylene (PE) trays, then were stored for 6 and 8 days (95% relative humidity). The parameters measured were: respiratory rate, color, total soluble solids, titratable acidity (TA) and sensory quality. Both trials showed a decrease in respiratory rate during the storage for all treatments. Treatment of 0 °C showed significantly lower rates as compared to the others two treatments with values of 13.9 to 27.6 mg CO2 · kg-1 · h-1 for trial 1 and 19.2 to 39.8 mg CO2 · kg-1 · h-1 for trial 2. Treatment at 5 °C reached 23.1 to 45.1 mg CO2 · kg-1 · h -1 and 21.4 to 58.6 mg CO2 · kg-1 · h-1, during trials 1 and 2 respectively. Treatment at 8 ºC, showed significantly higher rates, recording ranges from 30.2 to 47.0 mg CO2 · kg-1 · h-1 in trial 1 and 38.1 to 88.2 mg CO2 · kg-1 · h-1 in trial 2. Significant increases in the percentage of TA along storage days for the three treatments, in trial 1. Regarding the evolution of sensory quality, differences were observed in trial 1, appearance and intensity parameters of color, were the higher score was at 8 °C, compared to others. In trial 2, treatment at 8 ºC was the best evaluated for appearance, however, was the worst evaluated for the presence of off odour.
10

Efecto de la radiación UV-C sobre la calidad en brotes de alfalfa (medicago sativa L.) conservados en atmósferas modificadas

Tardón Machuca, Alejandro Antonio January 2011 (has links)
Memoria para optar al título profesional de Ingeniero Agrónomo / La industria de hortalizas mínimamente procesadas en fresco (MPF) utiliza comúnmente lavados con hipoclorito de sodio (NaClO) para disminuir la carga microbiana del producto, sin embargo, éste genera subproductos perjudiciales para la salud. Por esto, la necesidad de encontrar nuevas tecnologías emergentes y sostenibles como la radiación UV-C. El presente trabajo tuvo como objetivo evaluar el efecto de la aplicación de diferentes dosis de radiación UV-C sobre la calidad de brotes de alfalfa envasados en atmósfera modificada. Se realizaron dos ensayos utilizando bolsas de baja y alta permeabilidad. Los brotes fueron lavados con agua potable y tratados con UV-C en dosis de 0,35, 5,26, 10,18, 15,09 y 20,01 kJ m-2. Tras la aplicación del tratamiento UV-C, los brotes se envasaron en atmósfera modificada y se almacenaron a 5 °C por 8 días. Como testigo se utilizaron brotes lavados con NaClO (100 mg L-1) y envasados de la misma forma. Se evaluó la tasa respiratoria, composición gaseosa al interior de las bolsas, color, análisis microbiológico y sensorial. La combinación de radiación UV-C con bolsas de baja permeabilidad no fue efectiva para mantener la calidad en los brotes de alfalfa. La tasa respiratoria de los brotes no se vio afectada por las dosis de radiación utilizadas. La concentración gaseosa al interior de las bolsas registró valores de 19 a 23% CO2 y 1,5% para O2 tras 8 días, no influyendo las distintas dosis de radiación utilizadas. Los tratamientos con NaClO y en especial el tratamiento en bolsa perforada, reflejaron un menor pardeamiento en comparación a los tratamientos con dosis elevadas de UV-C (15,09 y 20,01 kJ m-2). El tratamiento con dosis de 20,01 kJ m-2 obtuvo los recuentos más elevados en mésofilos y psicrófilos, mientras que en enterobacterias, Lactobacillus, además de hongos y levaduras no existieron diferencias entre los distintos tratamientos, no obstante los conteos se encontraron dentro de los límites permitidos. La calidad sensorial de los brotes no registró diferencias significativas entre los tratamientos, sin embargo presentaron un deterioro evidente fuera de los límites de aceptabilidad fijados, teniendo un potencial de almacenamiento no superior a 4 o 5 días. Las bolsas de alta permeabilidad en conjunto con la aplicación de radiación UV-C, fueron efectivas para mantener la calidad general en brotes de alfalfa. La tasa respiratoria no se vio afectada por las distintas dosis de radiación utilizada. Al interior de las bolsas, se registraron concentraciones gaseosas de 2 a 3% para CO2 y 4 a 8% para O2 luego de 8 días. La radiación UV-C permitió mantener el color de los brotes, registrando diferencias sólo los tratamientos 10,18 y 20,01 kJ m-2 que presentaron un color más intenso (mayor C*), mientras que la L y Hab se mantuvieron sin diferencias significativas. Las dosis (15,09 y 20,01 kJ m-2) proporcionaron un control efectivo sobre el crecimiento de mesófilos, psicrófilos, enterobacterias, además de hongos y levaduras, mientras que dosis bajas y medias de radiación registraron conteos más elevados. Las distintas dosis de radiación UVC permitieron mantener la calidad sensorial de los brotes. La apariencia y turgencia se mantuvieron dentro de los rangos “más que regular” a “buena”, la intensidad de color dentro del rangos “bueno” a “muy bueno” y la presencia de sabores extraños dentro de los rangos “sin sabor” a “muy suave”, dentro de los límites permitidos. / The minimally processed fresh vegetables (MPF) industry commonly uses sodium hypochlorite (NaClO) washings to reduce the microbial load. However, it generates harmful by-products to health. Therefore, it is necessary to study new emerging and sustainable technologies such as the UV-C radiation. The aim of this study was to evaluate the effect of applying different UV-C radiation doses on the quality of germinated alfalfa in modified atmosphere packaging. Two trials were conducted using low and high permeability bags. The germinated alfalfa was washed with water and treated with 0.35, 5.26, 10.18, 15.09 and 20.01 kJ m-2 UV-C doses. Then, the germinated alfalfa was packed in modified atmosphere and stored at 5 °C for 8 d. Control outbreaks were washed with NaClO (100 mg L-1) and packaged in the same way. The respiration rate, atmosphere composition, colour, microbiological and sensory quality were evaluated. The combination of UV-C radiation with low permeability bags was not effective in maintaining the germinated alfalfa quality. The respiration rate was not affected by the UVC radiation doses. The atmosphere composition inside the bags showed values ranging from 19 to 23% CO2 and 1.5% O2 after 8 d, but it was not influenced by the different UV-C radiation doses. The treatments with NaClO and specially the treatment in perforated bag showed less enzymatic browning compared to germinated alfalfa treated with high UV-C doses (15.09 and 20.01 kJ m-2). Treatment with 20.01 kJ m-2 doses reported the highest counts for mesophilic and psycrophilic microorganisms, while enterobacteria, Lactobacillus, yeasts and fungi did not show significantly statistical differences between treatments and the values were within the legal permitted limits. The sensory quality of the germinated alfalfa did not differ significantly between treatments, but showed a clear deterioration beyond the set limits for acceptability, having a storage potential no longer than 4 or 5 d. The bags of high permeability in conjunction with UV-C radiation were effective in maintaining the overall quality of germinated alfalfa. The respiration rate was not affected by the UV-C radiation doses. The internal atmosphere composition was 2 to 3% CO2 and 4 to 8% O2 after 8 d. Treatments with UV-C radiation doses at 10.18 and 20.01 kJ m-2 allowed the outbreak colour to be preserved. However, germinated alfalfa treated at 20.01 kJ m-2 had a deeper colour (higher C*), while L and Hab stayed without statistical significantly differences. Doses at 15.09 and 20.01 kJ m-2 provided an effective growth control for mesophilic, psycrophilic, enterobacteria, fungi and yeasts, while low and medium UV-C radiation doses reported higher counts. Different UV-C radiation doses maintained the sensory quality of germinated alfalfa. Grades for appearance and turgidity ranged from "rather than regular" to "good", while colour intensity was graded as "good" to "very good" and off flavours ranged from "no flavour" to "too soft", within the set permitted limits.

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