Détail de l'auteur
Auteur Abdelghani Boudjellal |
Documents disponibles écrits par cet auteur (11)
Affiner la recherche Interroger des sources externesAccumulation de triglycerides par la levure oleagineuse Yarrowia Lipolytica / Doria Naila Bouchedja (Née Benzeghda)
Titre : Accumulation de triglycerides par la levure oleagineuse Yarrowia Lipolytica : maitrise et suivi des processus biologiques Type de document : texte imprimé Auteurs : Doria Naila Bouchedja (Née Benzeghda), Auteur ; Abdelghani Boudjellal, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 136 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Yarrowia lipolytica Accumulation lipidique Assimilation lipidique Croissance microbienne Dimorphisme cellulaire Cytométrie en flux en ligne Métabolisme lipidique levure oléagineuse Lipid accumulation Lipid assimilation Microbial growth Cell dimorphism On-line flow cytometry Lipid metabolism Oleaginous yeasts تخزين الدهون استيعاب الدهون والنمو الميكروبي إزدواج
المرفلوجيا الخلوية السيتومترية استقلاب الدهون الخميرة الزيتيةIndex. décimale : 636 Sciences Vétérinaires Résumé : The objective of the present thesis deals mainly with the study of the incorporation
and the accumulation of lipids by the fatty yeast Yarrowia lipolytica seen in different aspects.
The work was emphasized through the following aspects: growth and lipid accumulation of
cultured yeast in four different media types, effect of pH on the foaming phenomenon of the
culture medium in the bioreactor, effect of culture parameters on the different phenomena
occurring during a culture of the studied microorganism, through the development of an original
technique consisting of an in-line coupling between bioreactors and a flow cytometer. The latter
allowed the on-line and continuous monitoring of the effect of crop parameters and finally the
investigation of cell growth and lipid incorporation in three genetically modified strains of Y.
lipolytica. The study revealed that yeast had the ability to grow and accumulate lipids from very
different culture media, including those consisting of industrial by-products. However, the rates
of growth, incorporation and lipid accumulation differed according to the strain involved. The
technique of in-line cytometry has shed light on the effect of aeration and pH on cellular growth
phenomena of lipid accumulation and dimorphism in Y.lipolytica. High oxygenation had an
accelerating effect on growth and metabolization of accumulated lipids, while a critical pH level
had a downright inhibitory effect. The transition from mycelial to non-mycelial round was also
influenced by oxygen and pH. The modulation of the latter has proven to be effective in
controlling the foaming phenomenon in bioreactors. Therefore, by modifying the pH values, it
was possible to neutralize the foam without affecting the microorganism.Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/BOU7149.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10454 Accumulation de triglycerides par la levure oleagineuse Yarrowia Lipolytica : maitrise et suivi des processus biologiques [texte imprimé] / Doria Naila Bouchedja (Née Benzeghda), Auteur ; Abdelghani Boudjellal, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2017 . - 136 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Yarrowia lipolytica Accumulation lipidique Assimilation lipidique Croissance microbienne Dimorphisme cellulaire Cytométrie en flux en ligne Métabolisme lipidique levure oléagineuse Lipid accumulation Lipid assimilation Microbial growth Cell dimorphism On-line flow cytometry Lipid metabolism Oleaginous yeasts تخزين الدهون استيعاب الدهون والنمو الميكروبي إزدواج
المرفلوجيا الخلوية السيتومترية استقلاب الدهون الخميرة الزيتيةIndex. décimale : 636 Sciences Vétérinaires Résumé : The objective of the present thesis deals mainly with the study of the incorporation
and the accumulation of lipids by the fatty yeast Yarrowia lipolytica seen in different aspects.
The work was emphasized through the following aspects: growth and lipid accumulation of
cultured yeast in four different media types, effect of pH on the foaming phenomenon of the
culture medium in the bioreactor, effect of culture parameters on the different phenomena
occurring during a culture of the studied microorganism, through the development of an original
technique consisting of an in-line coupling between bioreactors and a flow cytometer. The latter
allowed the on-line and continuous monitoring of the effect of crop parameters and finally the
investigation of cell growth and lipid incorporation in three genetically modified strains of Y.
lipolytica. The study revealed that yeast had the ability to grow and accumulate lipids from very
different culture media, including those consisting of industrial by-products. However, the rates
of growth, incorporation and lipid accumulation differed according to the strain involved. The
technique of in-line cytometry has shed light on the effect of aeration and pH on cellular growth
phenomena of lipid accumulation and dimorphism in Y.lipolytica. High oxygenation had an
accelerating effect on growth and metabolization of accumulated lipids, while a critical pH level
had a downright inhibitory effect. The transition from mycelial to non-mycelial round was also
influenced by oxygen and pH. The modulation of the latter has proven to be effective in
controlling the foaming phenomenon in bioreactors. Therefore, by modifying the pH values, it
was possible to neutralize the foam without affecting the microorganism.Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/BOU7149.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10454 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7149 BOU/7149 Thèse Bibliothèque principale Thèses Disponible
Titre : Biomarqueurs des qualités sensorielles de la viande bovine : Compréhension des mécanismes et prédiction Type de document : texte imprimé Auteurs : Mohammed Gagaoua, Auteur ; B Picard, Directeur de thèse ; Abdelghani Boudjellal, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2015 Importance : 201 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Beef meat Muscle characteristics Sensory qualities Tenderness Meat color Biomarkers Biological mechanisms Prediction Viande bovine Caractéristiques musculaires Qualités sensorielles Tendreté Couleur Biomarqueurs Mécanismes biologiques Prédiction لحم البقر الخصائص العضلیة الصفات الحسیة الطراوة اللون المؤشرات الحیویة الآلیات البیولوجیة التنبؤ Index. décimale : 640 Industrie Alimentaire Résumé : Meat sensory quality is very variable and depends on many interrelated pre- and post-slaughter factors. The objective of this thesis is to explain by a mechanistic view the variation of several meat quality traits coming from different types of cattle (steers, heifers and young bulls) of numerous breeds using muscle characteristics and a list of 21 biomarkers of meat tenderness.
Findings from this thesis provide new insights in the biological mechanisms underlying the development of tenderness, color and pH of beef meat. The first part deals with the effect of cooking temperature and origin of panelists on the scores of meat sensory qualities. The results showed that irrespectively of animal type and origin of the panelists, tenderness and juiciness scores were higher at an end-point cooking temperature of 55°C than at 74°C. In contrast, beef flavor and overall liking scores were higher at 74°C than at 55°C. The second part of the thesis focuses on the relationship between muscle characteristics and sensory qualities. The results mainly show that the activity of the oxidative enzyme isocitrate dehydrogenase (ICDH) and the proportions of the slow myosin heavy chain (MyHC-I) allow discrimination of breeds irrespectively of animal type. However, none of the muscle characteristic was correlated with the evaluated sensory quality traits. The third and principal part of this thesis focuses on the use of the
biomarkers abundances to explain and predict the main meat quality traits. The prediction models taking in to account all young bulls breeds (Aberdeen Angus, Limousin and Blonde d'Aquitaine), explain only a small part (10 - 17%) of the variability of tenderness. However, the prediction power of the models constructed by breed were good, explaining up to 70% of the variability of tenderness of Longissimus thoracis and Semitendinosus muscles of the young bulls. Prediction
models built by muscle and breed showed many differences. Some biomarkers were common to both muscles and/or three breeds. Particularly, Hsp70-1A/B appears as a potential generic biomarker of tenderness, while other proteins were muscle and/or breed specific. In addition, this thesis is the first to show prediction equations of beef meat color and pH using the list of 21 biomarkers. Its originality consists in the use of muscle samples sampled early post-mortem.
Hsp70-1A/B and μ-calpain were highly correlated with each other and with all the meat color parameters. Based on these results, a biological mechanism was proposed to explain this strong correlation, suggesting the involvement of two phenomena: protein oxidation and apoptosis.
Moreover, many biomarkers were correlated with pH45min, pH3h and ultimate pH. Prdx6 was associated with the three parameters of pH and a possible biological mechanism was proposed.
The last part of this thesis focuses on the use of interactomics and shows the correlation networks between the 21 biomarkers studied. The networks identified the metabolic pathways and proteins (DJ-1, Hsp70-Grp75 and small Hsp) which may be strongly linked to meat quality traits irrespective of muscle and breed. Finally, an integrative mechanistic scheme using the biomarkers studied is proposed to describe the mechanisms that govern the steps of post-mortem muscle to meat conversion and preliminary results on the integration of serpins in the list of biomarkers are presented.
Diplôme : Doctorat en sciences Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10072 Biomarqueurs des qualités sensorielles de la viande bovine : Compréhension des mécanismes et prédiction [texte imprimé] / Mohammed Gagaoua, Auteur ; B Picard, Directeur de thèse ; Abdelghani Boudjellal, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2015 . - 201 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Beef meat Muscle characteristics Sensory qualities Tenderness Meat color Biomarkers Biological mechanisms Prediction Viande bovine Caractéristiques musculaires Qualités sensorielles Tendreté Couleur Biomarqueurs Mécanismes biologiques Prédiction لحم البقر الخصائص العضلیة الصفات الحسیة الطراوة اللون المؤشرات الحیویة الآلیات البیولوجیة التنبؤ Index. décimale : 640 Industrie Alimentaire Résumé : Meat sensory quality is very variable and depends on many interrelated pre- and post-slaughter factors. The objective of this thesis is to explain by a mechanistic view the variation of several meat quality traits coming from different types of cattle (steers, heifers and young bulls) of numerous breeds using muscle characteristics and a list of 21 biomarkers of meat tenderness.
Findings from this thesis provide new insights in the biological mechanisms underlying the development of tenderness, color and pH of beef meat. The first part deals with the effect of cooking temperature and origin of panelists on the scores of meat sensory qualities. The results showed that irrespectively of animal type and origin of the panelists, tenderness and juiciness scores were higher at an end-point cooking temperature of 55°C than at 74°C. In contrast, beef flavor and overall liking scores were higher at 74°C than at 55°C. The second part of the thesis focuses on the relationship between muscle characteristics and sensory qualities. The results mainly show that the activity of the oxidative enzyme isocitrate dehydrogenase (ICDH) and the proportions of the slow myosin heavy chain (MyHC-I) allow discrimination of breeds irrespectively of animal type. However, none of the muscle characteristic was correlated with the evaluated sensory quality traits. The third and principal part of this thesis focuses on the use of the
biomarkers abundances to explain and predict the main meat quality traits. The prediction models taking in to account all young bulls breeds (Aberdeen Angus, Limousin and Blonde d'Aquitaine), explain only a small part (10 - 17%) of the variability of tenderness. However, the prediction power of the models constructed by breed were good, explaining up to 70% of the variability of tenderness of Longissimus thoracis and Semitendinosus muscles of the young bulls. Prediction
models built by muscle and breed showed many differences. Some biomarkers were common to both muscles and/or three breeds. Particularly, Hsp70-1A/B appears as a potential generic biomarker of tenderness, while other proteins were muscle and/or breed specific. In addition, this thesis is the first to show prediction equations of beef meat color and pH using the list of 21 biomarkers. Its originality consists in the use of muscle samples sampled early post-mortem.
Hsp70-1A/B and μ-calpain were highly correlated with each other and with all the meat color parameters. Based on these results, a biological mechanism was proposed to explain this strong correlation, suggesting the involvement of two phenomena: protein oxidation and apoptosis.
Moreover, many biomarkers were correlated with pH45min, pH3h and ultimate pH. Prdx6 was associated with the three parameters of pH and a possible biological mechanism was proposed.
The last part of this thesis focuses on the use of interactomics and shows the correlation networks between the 21 biomarkers studied. The networks identified the metabolic pathways and proteins (DJ-1, Hsp70-Grp75 and small Hsp) which may be strongly linked to meat quality traits irrespective of muscle and breed. Finally, an integrative mechanistic scheme using the biomarkers studied is proposed to describe the mechanisms that govern the steps of post-mortem muscle to meat conversion and preliminary results on the integration of serpins in the list of biomarkers are presented.
Diplôme : Doctorat en sciences Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10072 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité GAG/6813 GAG/6813 Thèse Bibliothèque principale Thèses Disponible
Titre : Effet de l'âge à l’abattage sur les caractéristiques de la carcasse et la qualité de la viande des poules pondeuses de réformes de la souche ISA (F15) Type de document : texte imprimé Auteurs : Kahina Hafid ep. Boulouh, Auteur ; Abdelghani Boudjellal, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 110 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Poules pondeuses souche ISA F15 muscle pectoral pénétromètre analyse sensorielle âge spent hens ISA F15 meat penetrometer sensory analysis age الدجاج البياض العضلات الصدرية بينيتروميتر التحليل الحسي العمر Index. décimale : 640 Industrie Alimentaire Résumé : The intense production of eggs in Algeria, leads to an overabundant and availability of spent hens. Hens’ meat is perceived and judged to be very tough and undesirable for direct consumption; henceit is entirely oriented tothe transformation. The main objective of this preliminary study was to study the effect of slaughter age on the carcass traits and meat quality of ISA (F15) spent hens, the largest produced poultry in Algeria. To reach those objectives, total of 16 spent hens at different ages (220 vs 337 days, 8 animals per batch) were used. Toughness and texture/acceptability attributes (tenderness, juiciness, cohesiveness, chewiness, residues and overall liking) of breast muscle have been assessed by penetrometry and sensory analysis using a trained panel, respectively. Water holding capacity, percentage of released water, cooking losses, ultimate pH andmyofibril fragmentation index (MFI) were also determined.A proteomiccharacterization of sarcoplasmic and myofibrillar proteins was done on eachanimal of the two hensgroup. The preliminary results of this study showed that the penetration depth was negatively correlated with tenderness scoresand myofibril fragmentation index. Tenderness scores were negatively correlated with animal age and positively with ultimate pH. The meat of the studied hens has been judged very acceptable according to the highest scores (scores > 5.5/10) given by the panelists. Consequently, it appears that the overall liking scores are independent of hens’age. Otherwise, monodimensionalSDS-PAGE analysis displayed some differences in the proteomicprofiles of the two groupsin spite ofthe usefulness of the bi-dimensional electrophoresis (2-DE) in this study
to determine the underlying mechanisms oftoughness/tenderness. Through this preliminary study, it seems thatISA F15 spent hens can be used for a domestic consumption.
Diplôme : Magistère En ligne : ../theses/agronomie/HAF6768.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9845 Effet de l'âge à l’abattage sur les caractéristiques de la carcasse et la qualité de la viande des poules pondeuses de réformes de la souche ISA (F15) [texte imprimé] / Kahina Hafid ep. Boulouh, Auteur ; Abdelghani Boudjellal, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 110 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Poules pondeuses souche ISA F15 muscle pectoral pénétromètre analyse sensorielle âge spent hens ISA F15 meat penetrometer sensory analysis age الدجاج البياض العضلات الصدرية بينيتروميتر التحليل الحسي العمر Index. décimale : 640 Industrie Alimentaire Résumé : The intense production of eggs in Algeria, leads to an overabundant and availability of spent hens. Hens’ meat is perceived and judged to be very tough and undesirable for direct consumption; henceit is entirely oriented tothe transformation. The main objective of this preliminary study was to study the effect of slaughter age on the carcass traits and meat quality of ISA (F15) spent hens, the largest produced poultry in Algeria. To reach those objectives, total of 16 spent hens at different ages (220 vs 337 days, 8 animals per batch) were used. Toughness and texture/acceptability attributes (tenderness, juiciness, cohesiveness, chewiness, residues and overall liking) of breast muscle have been assessed by penetrometry and sensory analysis using a trained panel, respectively. Water holding capacity, percentage of released water, cooking losses, ultimate pH andmyofibril fragmentation index (MFI) were also determined.A proteomiccharacterization of sarcoplasmic and myofibrillar proteins was done on eachanimal of the two hensgroup. The preliminary results of this study showed that the penetration depth was negatively correlated with tenderness scoresand myofibril fragmentation index. Tenderness scores were negatively correlated with animal age and positively with ultimate pH. The meat of the studied hens has been judged very acceptable according to the highest scores (scores > 5.5/10) given by the panelists. Consequently, it appears that the overall liking scores are independent of hens’age. Otherwise, monodimensionalSDS-PAGE analysis displayed some differences in the proteomicprofiles of the two groupsin spite ofthe usefulness of the bi-dimensional electrophoresis (2-DE) in this study
to determine the underlying mechanisms oftoughness/tenderness. Through this preliminary study, it seems thatISA F15 spent hens can be used for a domestic consumption.
Diplôme : Magistère En ligne : ../theses/agronomie/HAF6768.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9845 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité HAF/6768 HAF/6768 Thèse Bibliothèque principale Thèses Disponible
Titre : Effets des antioxydants naturels issus de Pituranthos scoparius et Hibiscus sabdariffa sur la stabilité oxydative d’émulsions à base de lactosérum et la cristallisation des lipides. Type de document : texte imprimé Auteurs : Anis Chikhoune, Auteur ; Abdelghani Boudjellal, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 323 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Technologies Alimentaires: Sciences Alimentaires extraits phénoliques bruts huiles essentielles Pituranthos scoparius Hibiscus sabdariffa émulsion lactosérum stabilité oxydative interactions protéine-polyphénols monoterpènes cristallisation crude phenolic extracts essential oils emulsion whey oxidative stability protein-polyphenol interactions monoterpenes crystallization مستخلصات فينولية خام زيوت أساسية مستحلب مصل اللبن الاستقرار التأكسدي تفاعلات البروتين-البوليفينول مونوتربين التبلور Index. décimale : 640 Industrie Alimentaire Résumé : Nowadays, antioxidants have a significant impact on both human health and food processing. This thesis sheds the light on the action of these antioxidants on the oxidative stability of a whey-based spread-type emulsion, but also the crystallization of fats in the fatty phase. The crude phenolic extracts of Pituranthos scoparius and Hibiscus sabdariffa and the essential oils of the aerial parts of P. scoparius were studied. These extracts were obtained via conventional extraction techniques (decoction and hydrodistillation) and non-conventional techniques (microwaves and ultrasounds). Spectrophotometric assays were performed for the assessment of the contents of total phenolics in the crude extracts studied. Various chromatographic
techniques have been performed for the characterization and identification of the different classes of antioxidants. The antioxidant activity was studied by the tests of reducing power and antiradical activity. Different emulsions were formulated at both laboratory and pilot scales, incorporated by the concentrated crude phenolic extracts of the plants and the essential oil from stems of P. scoparius at different concentrations. Their oxidative stability was evaluated by Rancimat test. The two phases of the emulsion have been studied regarding two aspects: whey protein-polyphenol interactions in the aqueous phase and lipid crystallization in the fatty phase containing palm, soybean and sunflower oils. A Tricine SDS-PAGE was performed in the former and a set of investigation techniques for the study of isothermal crystallization (DSC, p-NMR and PLM) in the latter were applied. The results of spectrophotometric, chromatographic and antioxidant activity corroborate with those of oxidative stability and showed a protective effect against lipid oxidation at low concentrations of plant crude extracts (100 and 300 ppm) and the essential oil of P. scoparius (100 ppm). The sensory evaluation of the spread at 100, 300 and 600 ppm of the essential oil of P. scoparius, with a principal component analysis (PCA), revealed the influence of some sensory attributes on the segregation of emulsions at these different concentrations. The interactions of caseins and β-Lactoglobulin with polyphenols in the aqueous phase, with the formation of characteristic dimers, were revealed by densitometry and LC-MS/MS analysis. The formation of these dimers did not affect in any case the oxidative stability of the emulsions tested. The study of the effect of essential oils of stems and flowers of P. scoparius on lipid crystallization (palm oil alone and a mixture of the oils) showed a change in isothermal crystallization behavior of triglycerides with a delay of crystallization, a decrease in calculated enthalpies of fusion, slower crystallization rates and a drastic decrease in solid fat contents (SFC). This modification is also noticeable and different shapes and sizes of triglyceride crystals (spherulites) were visualized for fats with essential oils compared to control ones. The induction of a dilution effect of the system by the essential oils is discarded and the hypothesis of the implication of major monoterpenes in disturbing the crystallization events (nucleation and crystal growth) is proposed. From this study, it can be concluded that the recovery and industrial exploitation of the two plants studied is strongly encouraged, especially for P. scoparius which is already exploited in the Algerian traditional pharmacopoeia and food preservation. In addition to the antioxidant effects reported for the essential oil, it is suggested the possibility of its use as a natural additive to modify fat crystallization for applications in shortenings and various food emulsions.
Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/CHI7488.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11320 Effets des antioxydants naturels issus de Pituranthos scoparius et Hibiscus sabdariffa sur la stabilité oxydative d’émulsions à base de lactosérum et la cristallisation des lipides. [texte imprimé] / Anis Chikhoune, Auteur ; Abdelghani Boudjellal, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 323 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Technologies Alimentaires: Sciences Alimentaires extraits phénoliques bruts huiles essentielles Pituranthos scoparius Hibiscus sabdariffa émulsion lactosérum stabilité oxydative interactions protéine-polyphénols monoterpènes cristallisation crude phenolic extracts essential oils emulsion whey oxidative stability protein-polyphenol interactions monoterpenes crystallization مستخلصات فينولية خام زيوت أساسية مستحلب مصل اللبن الاستقرار التأكسدي تفاعلات البروتين-البوليفينول مونوتربين التبلور Index. décimale : 640 Industrie Alimentaire Résumé : Nowadays, antioxidants have a significant impact on both human health and food processing. This thesis sheds the light on the action of these antioxidants on the oxidative stability of a whey-based spread-type emulsion, but also the crystallization of fats in the fatty phase. The crude phenolic extracts of Pituranthos scoparius and Hibiscus sabdariffa and the essential oils of the aerial parts of P. scoparius were studied. These extracts were obtained via conventional extraction techniques (decoction and hydrodistillation) and non-conventional techniques (microwaves and ultrasounds). Spectrophotometric assays were performed for the assessment of the contents of total phenolics in the crude extracts studied. Various chromatographic
techniques have been performed for the characterization and identification of the different classes of antioxidants. The antioxidant activity was studied by the tests of reducing power and antiradical activity. Different emulsions were formulated at both laboratory and pilot scales, incorporated by the concentrated crude phenolic extracts of the plants and the essential oil from stems of P. scoparius at different concentrations. Their oxidative stability was evaluated by Rancimat test. The two phases of the emulsion have been studied regarding two aspects: whey protein-polyphenol interactions in the aqueous phase and lipid crystallization in the fatty phase containing palm, soybean and sunflower oils. A Tricine SDS-PAGE was performed in the former and a set of investigation techniques for the study of isothermal crystallization (DSC, p-NMR and PLM) in the latter were applied. The results of spectrophotometric, chromatographic and antioxidant activity corroborate with those of oxidative stability and showed a protective effect against lipid oxidation at low concentrations of plant crude extracts (100 and 300 ppm) and the essential oil of P. scoparius (100 ppm). The sensory evaluation of the spread at 100, 300 and 600 ppm of the essential oil of P. scoparius, with a principal component analysis (PCA), revealed the influence of some sensory attributes on the segregation of emulsions at these different concentrations. The interactions of caseins and β-Lactoglobulin with polyphenols in the aqueous phase, with the formation of characteristic dimers, were revealed by densitometry and LC-MS/MS analysis. The formation of these dimers did not affect in any case the oxidative stability of the emulsions tested. The study of the effect of essential oils of stems and flowers of P. scoparius on lipid crystallization (palm oil alone and a mixture of the oils) showed a change in isothermal crystallization behavior of triglycerides with a delay of crystallization, a decrease in calculated enthalpies of fusion, slower crystallization rates and a drastic decrease in solid fat contents (SFC). This modification is also noticeable and different shapes and sizes of triglyceride crystals (spherulites) were visualized for fats with essential oils compared to control ones. The induction of a dilution effect of the system by the essential oils is discarded and the hypothesis of the implication of major monoterpenes in disturbing the crystallization events (nucleation and crystal growth) is proposed. From this study, it can be concluded that the recovery and industrial exploitation of the two plants studied is strongly encouraged, especially for P. scoparius which is already exploited in the Algerian traditional pharmacopoeia and food preservation. In addition to the antioxidant effects reported for the essential oil, it is suggested the possibility of its use as a natural additive to modify fat crystallization for applications in shortenings and various food emulsions.
Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/CHI7488.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11320 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHI/7488 CHI/7488 Thèse Bibliothèque principale Thèses Disponible 
Titre : Etude de parametres physico-chimiques et biochimiques en cinetique au cours de la maturation de la viande de dromadaire Type de document : texte imprimé Auteurs : Hanane Smili, Auteur ; Abdelghani Boudjellal, Directeur de thèse ; Abdelatif Adamou, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2014 Importance : 134 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : dromedary meat age tenderization pH drip loss proteolysis viande de dromadaire âge maturation exsudation protéolyse لحم الإبل العمر نضج الحموضة قدرة تخزین الماء تفكك البروتینات Index. décimale : 640 Industrie Alimentaire Résumé : The aim of this study is to contribute to the determination of the age at slaughter effect’s on dromedary (Camelus dromedarius) meat caractestic during tenderization by the studying physico-chemical, biochemical and technological parameters.
Twelve Sahraoui’s population dromedaries reared on extensive system and destined to commercialization are used. Three groups of age are investigated 1-4, 6-8 and 10-19 years. The Longissimus lumborum muscle excised within the first hour post-slaughter is used to characterize its contractile fiber type by the myosine heavy chains isoform separation on SDS PAGE. The evolution of pH and water holding capacity of myofibrillar proteins are characterized. The proteolysis of myofibrillar proteins during tenderization is estimated by SDS PAGE. And actin fragments are revealed by western blot analysis.
Finally, the drip loss of the muscle during conservation at 5°C, is estimated.
The carcass yield is the highest with 68% for 6-8 years dromedaries. The Longissimus lumborum muscle is characterized by the presence of MyHC IIa, with no effect of age at slaughter. However, significant effect of age on pH drop is noted. In average, it falls from 6.68 to 5.71; with highest value for 1-4 years dromedaries. The rate
and the extent of pH fall are greater with increased age. One or two stability steps are observed. Water holding capacity of myofibrillar proteins increased with tenderization, with highest value observed for the youngest animals.
Important post mortem proteolysis is seen after 10h post-slaughter for 6-8 years animals. The actin is degraded since 1h post mortem and the fragments revealed are of about 36, 33 and 31 kDa. Small fragments of about 14 kDa are generated earlier with increased age, contrary to the 26 kDa fragments.
Drip loss of the muscle during conservation at 5°C is on average 7% during the 72h post mortem. The percentage of exudation is greater for the group of 10-19 years. Drip loss of the muscle generates financial losses for 10 kg of muscle varying between 300 to 600 DA.Diplôme : Magistère En ligne : ../theses/agronomie/SMI6448.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9483 Etude de parametres physico-chimiques et biochimiques en cinetique au cours de la maturation de la viande de dromadaire [texte imprimé] / Hanane Smili, Auteur ; Abdelghani Boudjellal, Directeur de thèse ; Abdelatif Adamou, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2014 . - 134 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : dromedary meat age tenderization pH drip loss proteolysis viande de dromadaire âge maturation exsudation protéolyse لحم الإبل العمر نضج الحموضة قدرة تخزین الماء تفكك البروتینات Index. décimale : 640 Industrie Alimentaire Résumé : The aim of this study is to contribute to the determination of the age at slaughter effect’s on dromedary (Camelus dromedarius) meat caractestic during tenderization by the studying physico-chemical, biochemical and technological parameters.
Twelve Sahraoui’s population dromedaries reared on extensive system and destined to commercialization are used. Three groups of age are investigated 1-4, 6-8 and 10-19 years. The Longissimus lumborum muscle excised within the first hour post-slaughter is used to characterize its contractile fiber type by the myosine heavy chains isoform separation on SDS PAGE. The evolution of pH and water holding capacity of myofibrillar proteins are characterized. The proteolysis of myofibrillar proteins during tenderization is estimated by SDS PAGE. And actin fragments are revealed by western blot analysis.
Finally, the drip loss of the muscle during conservation at 5°C, is estimated.
The carcass yield is the highest with 68% for 6-8 years dromedaries. The Longissimus lumborum muscle is characterized by the presence of MyHC IIa, with no effect of age at slaughter. However, significant effect of age on pH drop is noted. In average, it falls from 6.68 to 5.71; with highest value for 1-4 years dromedaries. The rate
and the extent of pH fall are greater with increased age. One or two stability steps are observed. Water holding capacity of myofibrillar proteins increased with tenderization, with highest value observed for the youngest animals.
Important post mortem proteolysis is seen after 10h post-slaughter for 6-8 years animals. The actin is degraded since 1h post mortem and the fragments revealed are of about 36, 33 and 31 kDa. Small fragments of about 14 kDa are generated earlier with increased age, contrary to the 26 kDa fragments.
Drip loss of the muscle during conservation at 5°C is on average 7% during the 72h post mortem. The percentage of exudation is greater for the group of 10-19 years. Drip loss of the muscle generates financial losses for 10 kg of muscle varying between 300 to 600 DA.Diplôme : Magistère En ligne : ../theses/agronomie/SMI6448.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9483 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité SMI/6448 SMI/6448 Thèse Bibliothèque principale Thèses Disponible Documents numériques
texte intégraleAdobe Acrobat PDF
PermalinkPermalinkPermalinkPermalink
