Grãos secos de destilaria com solúveis (DDGS) são uma fonte alternativa protéica e energética, de baixo custo se comparado com a farinha de peixe e o farelo de soja. Neste estudo avaliou-se a influência dos diferentes níveis de DDGS no desempenho produtivo e reprodutivo de lambari-de-rabo amarelo, bem como analisou-se a viabilidade econômica deste produto. O delineamento experimental foi inteiramente casualizado composto de 4 tratamentos (níveis de DDGS) e 4 repetições. Foram elaboradas dietas contendo 0%, 10%, 20% e 30%, de DDGS em substituição parcial e total do farelo de soja e quirera de arroz. Um total de 2400 alevinos de lambari foram estocados em 16 tanques de 500L, contendo biofiltro e um sistema individual de recirculação de água, à densidade de 0,3 peixes/ L. Os peixes foram alimentados 4 vezes ao dia no primeiro mês e 2 vezes nos meses subsequentes durante 150 dias, à taxa diária do arraçoamento de 5% de peso vivo. Mensalmente os peixes foram pesados e no final determinou-se os parâmetros produtivos tais como: ganho de peso, índice de conversão alimentar, taxa de sobrevivência, taxa de crescimento específico, taxa de eficiência protéica, índice de crescimento instantâneo, taxa de ganho de peso, fator de condição corporal e composição química do corpo inteiro e do músculo. Após o período de alimentação foram determinados os seguintes parâmetros reprodutivos: índice gonadossomático, volume dos ovos, fertilidade inicial, fertilidade inicial relativa, taxa de fertilidade, índice de desova, fertilidade final, fertilidade final relativa, taxa de eclosão e sobrevivência, diâmetro dos ovos e do vitelo e comprimento das larvas. Foi feita a histologia das gônadas das fêmeas e dos machos e avaliação do sêmen. Também se analisou a viabilidade do uso do DDGS. Os dados foram submetidos à análise de variância (α = 0,05), à regressão e teste de tendência, e para a comparação das médias de viabilidade económica utilizou-se o teste Tukey por meio do programa SAS. A adição de DDGS não afetou os parâmetros produtivos (P > 0,05), exceto para a matéria mineral do músculo (P < 0,05). Ocorreram diferenças (P < 0,05) para fertilidade inicial, peso, comprimento total e padrão dos machos. Histologicamente não se evidenciou diferenças entre as estruturas morfológicas dos ovários, nos testículos dos peixes alimentados com dieta de 30% de DDGS apresentaram células espermáticas abundantes, portanto o desenvolvimento gonadal não foi influenciado negativamente pelo DDGS. Economicamente as dietas contendo DDGS (10, 20 e 30%) foram respetivamente 2; 7 e 11% menos onerosas do que a dieta com farelo de soja e quirera de arroz. As médias do custo do ganho não diferiram (P > 0,05) entre si, indicando que se pode substituir o farelo de soja e quirera de arroz com o DDGS sem grandes prejuízos no desempenho e a baixo custo de alimentação. / Distillers dried grains with solubles (DDGS) is a protein and energy source alternative, is used to formulate diets to feed fishes in replecement of fish meal and soya, and the cost is low. This research was carried out to investigate the influence of dietary inclusion of DDGS levels on growth and reprodution performance and evaluate its economical value of lambari. The experimental delineament were four isonitrogenous diets were formulated that contain 0%, 10%, 20%, and 30% of DDGS in substituation of soja meal and broken rice. A total of 2400 lambari were stored in 16 tanks 500L, provided with a biofilter and a single system of water recirculation, density were 0,3 fish / L. During 150 days the groups of fish were fed with experimental diets until visual satiety four times per day for the first month and twice in the remaining months, the daily rate of feeding were 5% of body weight. Each month the fish were weighed for determination of production parameters such as: weight gain, feed conversion rate, survival rate, specific growth rate, protein efficiency ratio, instantaneous growth rate, weight gain rate, condition factor physical and chemical composition of the whole body and muscle. After the feeding period terminated reproductive parameters such as: gonadossomatic index, egg volume, initial fertility, relative initial fertility, fertility rate, spawning rate, final fertility, final relative fertility, hatching and survival rate, diameter of eggs and length of the larvae. It was made the histology of the gonads (females and males) and semen evaluation. Also analyzed the economic viability of using DDGS in the diets. The data were subjected to ANOVA, regression and trend test, economical value analised by Turkey test (α = 0,05). Addition of DDGS did not affect the productive parameters (P > 0,05) except for the mineral of muscle (P < 0,05). There were differences (P < 0,05) in initial fertility (FI), weight, total and pattern length of males. Histologically no detectable morphological differences between the structures of the ovaries, but testes of fish fed with diet of 30% DDGS showed abundant sperm cells, therefore gonadal development was not negatively influenced by the DDGS. Economically diets containing DDGS (10, 20 and 30%) were respectively 2; 7:11% cheaper than the diet with soy meal and broken rice. The cost gain was no significant (P > 0.05). The result from this resarch shows that DDGS can replace soybean meal and broken rice without major losses in performance and low cost supply.

Memoria para optar al Título Profesional de Ingeniero Agrónomo Mención: Fruticultura

In this Doctoral Thesis the study of the influence of the operating parameters of the activated sludge process on the physical and chemical characteristics of the mixed liquor, from different membrane bioreactors (MBR), has been carried out. In addition, an optical characterization of the mixing liquor has been performed. In order to achieve the above mentioned aim, samples of the mixed liquor from an MBR treating municipal wastewater were first analysed and then, the characteristics of two MBR mixed liquors treating the leachates from two treatment plants of the organic fraction of municipal solid waste (OFMSW) were evaluated. It is noteworthy that the difference between the two industrial MBR lies on the feeding (inlet) to the MBR, which is determined by the treatment performed to the OFMSW, since one of them consists of a wet anaerobic digestion (MBR-LS) and the other of a dry anaerobic digestion (MBR-HS), so that the latter leachate contains higher concentration of suspended solids in its composition. For the chemical characterization of the mixture liquor, the extracellular polymeric substances (EPS) have been analysed. EPS are formed by the sum of extracted extracellular polymeric substances (eEPS) and soluble microbial products (SMP). These substances are considered the main cause of membranes fouling in MBRs and are basically formed by proteins and polysaccharides, which can be both attached to the cell wall and outside the cell, in form of eEPS or SMP. Regarding the physical characterization, in particular it has been analysed and studied the effect on the membrane fouling of the total and volatile suspended solids, the viscosity, the capillary suction time and the particle size, measured through the resistance to filtration. Finally, in the municipal MBR, cell viability with epifluorescence microscopy has been studied, as well as the main components of EPS have been stained by two different methods. In addition, a statistical study has evaluated the effect of the main operating parameters of the MBR on the characterization parameters of the mixed liquor. By means of least squares regression, the operational parameters that influence SMP production in industrial MBR have been studied. The study was completed by evaluating the fouling of an ultrafiltration membrane with proteins extracted from EPS and subsequently purified with ammonium sulphate at different pH values. To this end, different synthetic proteins (bovine serum albumin, casein, haemoglobin and lysozyme) were first analysed and then compared with the proteins extracted from the mixed liquor. Membrane fouling with purified eEPS proteins has also been studied along with sodium alginate added in the same concentration as the proteins. The results obtained demonstrate, firstly, that SMP play an important role in the membrane fouling. The concentration of proteins has been considerably higher than that of carbohydrates both in SMP and in eEPS, although SMP influenced to a greater extent on the filtration of the activated sludge. In addition, it is shown that bacteria under stress conditions, caused for example by increase in conductivity, increase the production of SMP, and therefore, membrane fouling increases. On the other hand, it is concluded that a low hydraulic retention time favours a high carbohydrates concentration and consequently drives to an increase in the viscosity and capillary suction time, also increasing the membrane fouling. / En la presente Tesis Doctoral se ha llevado a cabo el estudio de la influencia de los parámetros de operación del proceso de fangos activos en las características físicas y químicas de los licores de mezcla, procedentes de diferentes biorreactores de membrana (MBR). Además, se ha realizado una caracterización óptica del licor de mezcla. Para ello, en primer lugar se tomaron muestras del licor de mezcla de un MBR que trata aguas residuales urbanas y, a continuación, se evaluaron las características de los licores de mezcla de dos MBR que tratan los lixiviados procedentes de dos plantas de tratamiento de la fracción orgánica de los residuos sólidos urbanos (FORSU). Cabe destacar que la diferencia entre los dos MBR industriales radica en la alimentación (afluentes) al MBR, que viene determinada por el tratamiento que se realiza a la FORSU, ya que uno de ellos consiste en una digestión anaerobia en vía húmeda (MBR-LS) y, el otro, en una digestión anaerobia en vía seca (MBR-HS), por lo que este último lixiviado contiene mayor concentración de sólidos en suspensión en su composición. Para la caracterización química del licor de mezcla, se han analizado las sustancias poliméricas extracelulares (EPS), formadas por la suma de las sustancias poliméricas extracelulares extraídas (eEPS) y los productos solubles microbianos (SMP). Estas sustancias se consideran las principales causantes del ensuciamiento de las membranas del MBR y están formadas básicamente por proteínas y polisacáridos, los cuales pueden estar tanto adheridos a la pared celular como fuera de la célula, en forma de eEPS o SMP. En cuanto a la caracterización física, en concreto se ha analizado y estudiado el efecto en el ensuciamiento de las membranas de los sólidos en suspensión totales y volátiles, la viscosidad, el tiempo de succión capilar y el tamaño de partícula, medido a través de las resistencias a la filtración. Finalmente, en el MBR urbano se ha estudiado la viabilidad celular con microscopía de epifluorescencia, así como se han teñido para su caracterización óptica los principales componentes de las EPS por dos métodos distintos. Además, mediante un estudio estadístico se ha evaluado el efecto de los principales parámetros de operación de los MBR sobre los parámetros de caracterización del licor de mezcla. Mediante regresión por mínimos cuadrados se han estudiado los parámetros operacionales que influyen en la producción de SMP en los MBR industriales. El estudio se ha completado evaluando el ensuciamiento de una membrana de ultrafiltración con proteínas extraídas de las EPS y posteriormente purificadas con sulfato amónico, a diferentes valores de pH. Para ello, en primer lugar se han caracterizado diferentes proteínas sintéticas (albúmina de suero bovino, caseína, hemoglobina y lisozima) para compararlas con las proteínas extraídas del licor de mezcla. También se ha estudiado el ensuciamiento de la membrana con las proteínas purificadas de las eEPS junto con alginato de sodio en la misma proporción. Los resultados obtenidos demuestran en primer lugar que los SMP juegan un papel importante en el ensuciamiento de las membranas. Tanto en su composición como en la de las eEPS, la concentración de proteínas determinada ha sido considerablemente mayor que la de carbohidratos, si bien éstos influyen incluso en mayor medida en la filtrabilidad del fango activo. Además, se demuestra que las bacterias bajo condiciones de estrés, causado por ejemplo por aumento de conductividad, aumentan la producción de SMP, y por tanto, se incrementa el ensuciamiento de las membranas. Por otro lado, se concluye que un tiempo de retención hidráulico bajo favorece una concentración elevada de carbohidratos y consecuentemente provoca un aumento de la viscosidad y el tiempo de succión capilar, aumentando también el ensuciamiento de la membrana. / En la present Tesi Doctoral s'ha dut a terme l'estudi de la influència dels paràmetres d'operació del procés de fangs actius en les característiques físiques i químiques de licors de mescla, procedents de diferents biorreactors de membrana (MBR). A més, s'ha realitzat una caracterització òptica del licor de mescla. Per a això, en primer lloc es van prendre mostres del licor de mescla d'un MBR que tracta aigües residuals urbanes i, a continuació, es van avaluar les característiques dels licors de mescla de dos MBR que tracten els lixiviats procedents de dues plantes de tractament de la fracció orgànica dels residus sòlids urbans (FORSU). Cal destacar que la diferència entre els dos MBR industrials radica en l'alimentació (afluents) al MBR, que ve determinada pel tractament que es realitza a la FORSU, ja que un d'ells consisteix en una digestió anaeròbia en via humida (MBR-LS) i, l'altre, en una digestió anaeròbia en via seca (MBR-HS), per la qual cosa este últim lixiviat conté major concentració de sòlids en suspensió en la seua composició. Per a la caracterització química del licor de mescla, s'han analitzat les substàncies polimèriques extracel¿lulars (EPS), formades per la suma de les substàncies polimèriques extracel¿lulars extretes (eEPS) i els productes solubles microbians (SMP). Estes substàncies es consideren les principals causants de l'embrutiment de les membranes del MBR i estan formades bàsicament per proteïnes i polisacàrids, els quals poden estar tant adherits a la paret cel¿lular com fora de la cèl¿lula, en forma d'eEPS o SMP. Quant a la caracterització física, en concret s'ha analitzat i estudiat l'efecte en l'embrutiment de les membranes dels sòlids en suspensió totals i volàtils, la viscositat, el temps de succió capil¿lar i la grandària de partícula, mesurat a través de les resistències a la filtració. Finalment, en el MBR urbà s'ha estudiat la viabilitat cel¿lular amb microscòpia d'epifluorescència, així com s'han tenyit per a la seua caracterització òptica els principals components de les EPS per dos mètodes distints. A més, per mitjà d'un estudi estadístic s'ha avaluat l'efecte dels principals paràmetres d'operació dels MBR sobre els paràmetres de caracterització del licor de mescla. Per mitjà de regressió per mínims quadrats s'han estudiat els paràmetres operacionals que influeixen en la producció de SMP en els MBR industrials. L'estudi s'ha completat avaluant l'embrutiment d'una membrana d'ultrafiltració amb proteïnes extretes de les EPS i posteriorment purificades amb sulfat amònic, a diferents valors de pH. Per a això, en primer lloc s'han caracteritzat diferents proteïnes sintètiques (albúmina de sèrum boví, caseïna, hemoglobina i lisozima) per a comparar-les amb les proteïnes extretes del licor de mescla. També s'ha estudiat l'embrutiment de la membrana amb les proteïnes purificades de les eEPS junt amb alginat de sodi en la mateixa proporció. Els resultats obtinguts demostren en primer lloc que els SMP juguen un paper important en l'embrutiment de les membranes. Tant en la seua composició com en la de les eEPS, la concentració de proteïnes determinada ha sigut considerablement major que la de carbohidrats, si bé estos influeixen inclús en major grau en la filtrabilidad del fang actiu. A més, es demostra que els bacteris baix condicions d'estrès, causat per exemple per augment de conductivitat, augmenten la producció de SMP, i per tant, s'incrementa l'embrutiment de les membranes. D'altra banda, es conclou que un temps de retenció hidràulic baix afavoreix una concentració elevada de carbohidrats i conseqüentment provoca un augment de la viscositat i el temps de succió capil¿lar, augmentant també l'embrutiment de la membrana. / Zuriaga Agustí, E. (2017). Influencia de las características físicas y químicas del licor de mezcla en Bioreactores de Membrana y su correlación con los parámetros de operación en aguas residuales urbanas e industriales [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90512 / TESIS

Thirty-six half-sibling Angus bulls were assigned one of three diets: 1) 60% corn-based (CON; S = 0.18%; n = 12); 2) 60% DDGS replacing corn (60DDGS; S = 0.55% DM; n = 12); 3) CON diet + equivalent sulfur of 60DDGS added as calcium sulfate (SULF; S = 0.54%; n = 12) to evaluate the effects of feeding diets containing DDGS or calcium sulfate on performance and semen characteristics. Bulls began the study at 9 months of age and gained 1.6 kg/day for 112 days. Treatment by day interactions (P < 0.05) were observed for glutathione peroxidase and trace mineral concentrations in seminal plasma. Effects of treatment (P < 0.05) were observed for semen kinematics and triiodothyronine in serum. Alterations observed when feeding 60% DDGS to developing bulls occurred in a manner that is not dependent on dietary sulfur; therefore, observed changes could be related to other components within DDGS.

Corn distiller’s dried grains with solubles (DDGS) is mostly marketed as a livestock feed due to its high protein content of 30%. Recently, the proteins in DDGS have shown potential to act as binding agents along with melamine-urea-formaldehyde resin. However, it is unknown if DDGS can be chemically functionalized as a natural binder to replace synthetic resin in particleboard. In this study, several formulations were tested using various concentrations of acetic acid and sodium hydroxide treatments with combinations of temperature, DDGS concentrations, particle sizes, and wax. FTIR results indicated that DDGS proteins were decoupled through acid or alkali treatments, and acid treated DDGS in particleboards displayed higher improvements in internal bond strength as well as the moisture resistance of the particleboards. These results suggest that acid or alkali treated DDGS has potential to act as a natural binder for manufacturing medium-density particleboard.

The objective of the experiments conducted for this dissertation was to determine the standardized ileal digestibility (SID) of amino acids (AA) in a variety of feed ingredients for broiler chickens and pigs. The effects of casein in experimental diets on the SID of AA in corn distillers’ dried grains with solubles (DDGS) fed to pigs were evaluated. The SID of AA in feed ingredients, which include full-fat soybean (FFSB), two soybean meals (SBM), peanut flour (PNF), full-fat canola seeds (FFCS), canola meal (CM), canola expellers (CE), hydrolyzed feather meal (HFM), flash dried poultry protein (FDPP), poultry meal (PM), and meat and bone meal (MBM), were compared in broiler chickens and pigs. One of the studies determined the ileal digestibility of AA in casein by regression analysis and investigated the effects of 60 g/kg casein in experimental diets on the SID of AA in DDGS. The ileal digestibility of AA in casein were close to 100%, ranging from 95.5% (SE = 9.10) for Cys to 103.1% (SE = 4.40) for Arg. In addition, the SID of Lys and Phe in DDGS determined by pigs fed the diet containing DDGS and casein were greater (<i>P</i> < 0.05) than the values determined by pigs fed the diet containing DDGS without casein. Based on the results of this experiment, two additional experiments were conducted to determine the effects of graded concentrations of casein from 55 to 165 g/kg in experimental diets on the SID of AA in DDGS and to determine the effects of dietary DDGS concentrations (i.e., 155.6 or 466.8 g/kg) and addition of casein in experimental diets on the SID of AA in DDGS. The SID of indispensable AA, except for Arg and Lys, linearly decreased (<i>P</i> < 0.05) as the concentration of casein in experimental diets increased. Moreover, pigs fed the diets containing 155.6 g/kg DDGS had less (<i>P</i> < 0.05) SID of indispensable AA, except for Trp, in DDGS than those fed the diets containing 466.8 g/kg DDGS regardless of the addition of casein in experimental diets. Therefore, it may be concluded that the addition of casein improves the SID of AA in DDGS, but reduced DDGS concentration in experimental diets decreases the SID of AA in DDGS. In one pair of experiments conducted to compare the SID of AA in FFSB, SBM containing 430 g/kg crude protein, SBM containing 470 g/kg crude protein, and PNF between broiler chickens and pigs, the SID of AA, except for Trp, Ala, and Glu, in test ingredients for pigs were greater (<i>P</i> < 0.05) than the values for broiler chickens. In addition, in both broiler chickens and pigs, the SID of Ile, Leu, and Val in FFSB were less (<i>P</i> < 0.05) than in the other test ingredients. In another pair of experiments conducted to compare the SID of AA in FFCS, CM, and CE between broiler chickens and pigs, interactions (<i>P</i> < 0.05) between experimental diets and species were observed in the SID of AA, except for Lys, Gly, Pro, and Ser. The SID of AA in FFCS for broiler chickens were greater (<i>P</i> < 0.05) than pigs; however, there was no difference in the SID of AA in CM or CE between broiler chickens and pigs. The objective of a third pair of experiments was to compare the SID of AA in HFM, FDPP, PM, and MBM fed to broiler chickens and pigs. There were interactions (<i>P</i> < 0.05) between experimental diets and species in the SID of His, Thr, Trp, and Val. In broiler chickens, the SID of His, Thr, and Trp in FDPP and PM were greater (<i>P</i> < 0.05) than in HFM but were less (<i>P</i> < 0.05) than MBM; however, difference in SID of His, Thr, and Trp among FDPP, PM, and MBM was not observed in pigs. Based on the results of three pairs of studies, it was revealed that differences in SID of AA in common feed ingredients for both broiler chickens and pigs were affected by species. Therefore, it may be concluded that the effects of feed ingredient-specific factors on the SID of AA are different between broiler chickens and pigs.

Master of Science / Department of Animal Sciences and Industry / Joel M. DeRouchey / A total of 6,858 pigs were used in 6 experiments to evaluate the effects of crude glycerol, dried distillers grains with solubles (DDGS), Ractopamine HCl (RAC), NutriDense corn, and feeder adjustment on growing and finishing pig performance. In Exp. 1, pigs were fed diets with 0, 2.5, or 5% crude glycerol with 0 or 20% DDGS. Adding DDGS increased ADFI and decreased G:F with no differences for pigs fed glycerol. Neither glycerol nor DDGS affected any carcass characteristics. Pigs fed DDGS had increased iodine value in carcass fat. In Exp. 2, pigs were fed diets with 0 or 5% glycerol with 0 or 7.5 ppm RAC. Feeding RAC increased ADG and G:F and decreased ADFI while glycerol tended to improve G:F. Ractopamine HCl improved carcass traits. Loin chop drip loss worsened when glycerol and RAC were added separately, however, drip loss decreased when the combination of both were fed. Glycerol did not affect loin characteristics. Neither RAC nor glycerol influenced iodine value of carcass fat. Exp. 3 and 4 were conducted to determine the 4th limiting amino acid in diets containing NutriDense corn. In Exp. 3, pigs fed the positive control and the diet with added Ile, Trp, and Val (in combination) had greater ADG. Pigs fed added Ile or Trp had greater ADG than pigs fed the negative control indicates these amino acids were co-4th limiting for 37 to 59 kg pigs. In Exp. 4, pigs fed the positive control, added Trp, or the combination of added Ile, Trp and Val had greater ADG then pigs fed the negative control or pigs fed either Ile or Val indicates these amino acids were co-4th limiting for 77 to 100 kg pigs. Exp. 5 and 6 evaluated feeder adjustment on growth performance of finishing pigs. In Exp. 5, reducing feeder opening decreased ADFI. In Exp. 6, pigs were fed at three feeder opening and either a corn-soybean meal or byproduct-based diet. Diet type did not affect pig performance. Widening feeder openings increased ADG and ADFI. Feeder setting tended to influence G:F with the best G:F at the intermediate opening.

Master of Science / Department of Animal Sciences and Industry / Terry A. Houser / A total of 48 carcasses were taken from a larger trial using 288 pigs (PIC TR4 × 1050, initially 58.9 kg) in a 73 d feeding study to determine the effects of sorghum dried distillers grains with solubles (S-DDGS) in sorghum- or corn-based diets on ground pork quality. The dietary treatments included: sorghum-based diets with 0, 15, 30, or 45% SDDGS, a sorghum-based diet with 30% corn DDGS (C-DDGS) and a corn-based diet with 30% C-DDGS. Shoulders from 24 barrow and 24 gilt carcasses were ground and evaluated for proximate and fatty acid composition, iodine value (IV), objective color, thiobarbituric acid-reactive substances (TBARS), and sensory attributes. No finishing diet × gender interaction was detected for composition, fatty acid profile, color or TBARS (P > 0.05). Pork from gilts contained less fat and more moisture (P < 0.001), was less saturated with a greater IV and total percentage of PUFA (P < 0.01), and also had a lower L* value (P < 0.001) and higher a* value (P = 0.006) than pork from barrows. Gender did not affect total color change ( E) from 0 to 120 h (P = 0.30), TBARS (P = 0.08), or sensory attributes (P ≥ 0.32). Finishing diet had no affect on total fat, moisture, or protein composition (P ≥ 0.18). Increasing S-DDGS resulted in a linear (P < 0.001) decrease in SFA and MUFA and an increase (P < 0.01) in PUFA and ground pork IV. Pork from pigs fed 30% S-DDGS had a greater percentage of MUFA (P = 0.01) and a lower percentage of PUFA (P > 0.006) and reduced IV (P = 0.03) compared to pork from pigs fed the sorghum-based diet with 30% C-DDGS. Diet did not affect TBARS (P = 0.37) or L*, a*, or b* values (P ≥ 0.11) but was shown to influence E (P = 0.01) with pork from pigs fed sorghum grain and 30% S-DDGS having less total change than all other treatments. It is concluded that consumers will not be able to differentiate ground pork from pigs fed DDGS and that feeding sorghum grain and S-DDGS can be done without affecting ground pork quality.

L’arboriculture en milieu méditerranéen nécessite un apport d’eau via l’irrigation important, notamment pendant la période estivale. Pour améliorer l’efficience d’utilisation de l’eau, il convient de mieux connaître les besoins en eau de l’arbre et les zones d’exploration et d’exploitation des racines. La croissance des racines varie dans le temps et dans l’espace en lien avec des facteurs endogènes, en particulier la disponibilité en assimilats carbonés, et des facteurs exogènes comme les propriétés du sol. Ces facteurs sont modulés par les pratiques culturales, et en particulier l’irrigation, le compactage du sol et l’éclaircissage, qui affectent la croissance racinaire, et d’une manière générale le fonctionnement global de l’arbre. La dynamique de croissance des racines est ponctuée par deux périodes de croissance intense. La première période de croissance intense se situe tôt dans la saison, en avril-mai, pendant la phase de durcissement du noyau des fruits. En début de saison la demande en carbone à l’échelle de l’arbre est importante (forte croissance des feuilles, fruits, rameaux, racines) et nécessite la mobilisation intense des réserves carbonées présentent sous forme d’amidon. La charge en fruits affecte la croissance des racines et des fruits, et la restriction hydrique affecte surtout la croissance de la partie aérienne. La deuxième période de croissance racinaire intense intervient après la récolte en juillet-août, quand les feuilles et les rameaux ont finis leur croissance. La compétition est moins forte et l’amidon s’accumule, surtout chez les arbres sous restriction hydrique. L’accumulation d’amidon résulte d’une plus grande sensibilité de la croissance au déficit hydrique que la photosynthèse. Pendant les périodes de croissances racinaires intenses, le diamètre apical et la longueur de leur zone apicale non ramifiée des racines sont augmentés, ainsi que les teneurs en sucres solubles dans les pointes racinaires. Les paramètres architecturaux racinaires et les teneurs en sucres solubles dans les pointes racinaires sont de bons indicateurs de la dynamique de croissance racinaire. La répartition des racines au verger est très variable et dépend des propriétés du sol. Les racines des arbres bien alimentés en eau ont colonisé surtout les volumes de sol sous le rang des arbres (proches des goutteurs) jusqu’à 1 m de profondeur. Au contraire les racines des arbres sous-alimentés en eau ont colonisé surtout les 50 cm en profondeur sous le rang et vers l’inter-rang. Les racines se sont réparties dans les zones les moins contraignantes pour leur croissance, qui sont plus restreintes quand l’irrigation est restrictive. En conditions non contraignantes, de par une faible densité de sol ou une forte teneur en eau, la vitesse de croissance, et notamment des grosses racines, est forte. Par contre, les fines racines ont une vitesse de pénétration des sols contraignants plus rapide. La contrainte mécanique entraîne aussi une baisse de la hiérarchisation des systèmes racinaires, les racines latérales seront davantage ramifiées / Fruit tree production in Mediterranean climate needs water supply via irrigation, particularly during summer. To improve water use efficiency, it is necessary to better understand the water need of tree and to localize soil volumes colonized by roots. Root growth varies in time and space following endogenous factors, like carbohydrate availability, and exogenous factors like soil properties. These factors are affected by cultural practices and particularly by irrigation, soil compaction and thinning. Root growth dynamics is marked by two intensive root growth periods. The first period of intensive root growth occurs early in the season, in April-May, during the phase of stone hardening of fruit. Early in the season, carbohydrates demand at tree scale is high (leaves, fruits, shoots, roots are growing) and leads to an intense mobilization of starch reserve. Crop load affects root and fruit growth, and the deficit irrigation affects principally the aerial growth. The second period of intensive root growth occurs after the fruit harvest in July-August, when leaves and shoot stopped their growth. Competition for carbohydrates is reduced and starch contents rise, particularly in trees submitted to deficit irrigation. Starch accumulation traduces a higher sensibility of growth than photosynthesis under deficit irrigation. During intensive root growth periods, apical diameter and the length of apical unbranched zone are increased, and water soluble carbohydrates contents in root tips too. Root architectural parameters and water soluble carbohydrates contents are good indicators of root growth dynamics. Root distribution in orchard is variable and depends of soil properties. Roots of wellirrigated trees colonized especially soil volumes in the row (under drippers) until 1 m in depth. On the opposite, root of trees submitted to deficit irrigation colonized the first 50 cm in depth, both in the row and the inter-row. Root colonized soil volumes where soil mechanical resistance was the lowest, and these soil volumes are more reduced in deficit irrigation. Low soil mechanical resistance, with low bulk density and high water content, allows a higher root elongation and particularly for thick roots. On the opposite, fine roots have a higher elongation in strength soil than thick roots. The soil mechanical resistance leads to reduce the root system hierarchy; lateral roots were more branched

Lors de la production des poudres protéiques laitières, des précautions sont prises pour assurer des fonctions technologiques optimales selon leurs utilisations. Cependant, des évolutions structurales et fonctionnelles surviennent lors du stockage. Ce projet vise ainsi à comprendre les mécanismes de modification qui interviennent lors du stockage des poudres d’isolat de protéines solubles du lait (WPI). Pour ce faire, des poudres de WPI ont été stockées en conditions contrôlées (15 mois à 20°C, 40°C et 60°C), et leurs évolutions structurales et fonctionnelles après réhydratation ont été suivies expérimentalement à intervalles réguliers.Les résultats montrent que le vieillissement suit une trajectoire définie impliquant d’abord la lactosylation d’une partie des protéines, puis leur agrégation à l’état sec. De plus, cette trajectoire est caractérisée par un phénomène de rattrapage des modifications observées aux basses températures vers les plus hautes. L’impact des évolutions structurales sur les propriétés fonctionnelles est contrasté : les résultats montrent que les propriétés moussantes et interfaciales sont peu affectées, alors que les propriétés d’agrégation thermo-induites sont grandement modifiées. Pour minimiser ces modifications, deux pistes d’amélioration ont été suivies : 1. la granulométrie des poudres et 2. la teneur en lactose résiduel. La différence de granulométrie n’a pas eu d’influence sur le vieillissement alors que la diminution de la teneur en lactose a permis de limiter significativement l’étendue des modifications induites lors du stockage. / During dairy powder manufacture, precautionary measures are taken to ensure optimal technological functionalities regarding their use requirements. However, changes in structural and functional properties appear during storage. This project aimed understand the mechanisms of changes that occur during storage of whey protein isolate (WPI) powders. To do this, WPI powders were stored under controlled conditions (20°C, 40°C and 60°C for 15 months), and their structural and functional changes after rehydration were experimentally monitored at regular intervals. The results showed that ageing follows a specific path involving first protein lactosylation and then their aggregation in the dry state. In addition, this path was characterized by a catching up behaviour from the changes obtained at lower temperatures to those at highest temperatures. The impact of these structural changes on the functional properties was mixed:the results showed that the foaming and interfacial properties were only slightly affected, while the heat-induced aggregation properties were greatly modified. To minimize these storage-induced changes, several areas for improvement were followed, playing on either the powder particle size, or on lactose content whose role appeared to be crucial for the development of the Maillard reaction. The study showed that the difference in powder particle size had no influence on their ageing path while lowering the lactose concentration allowed to significantly reduce the extent of the storage-induced changes.