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Auteur Farida Kehal |
Documents disponibles écrits par cet auteur (2)
Affiner la recherche Interroger des sources externesSavoirs traditionnels sur le séchage au soleil et la préparation de confiture de figues et effets sur la teneur, le profil, l’activité antioxydante et la bioaccessibilité in vitro des composés phénoliques. / Farida Kehal
Titre : Savoirs traditionnels sur le séchage au soleil et la préparation de confiture de figues et effets sur la teneur, le profil, l’activité antioxydante et la bioaccessibilité in vitro des composés phénoliques. Type de document : texte imprimé Auteurs : Farida Kehal, Auteur ; Malika Barkat, Directeur de thèse Mention d'édition : 04/01/2022 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2022 Importance : 204 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Technologies Alimentaires: Sciences Alimentaires Figues confiture séchage au soleil traditionnelle composés phénoliques activité antioxydante bioaccessibilité digestion gastro-intestinale in vitro Figs jam sun drying traditional phenolic compounds antioxidant activity bioaccessibility in vitro gastrointestinal digestion التين المربى التجفيف الشمسي المركبات الفينولية نشاط مضادات الأكسدة إمكانية الوصول
الحيوي الهضم المخبريIndex. décimale : 640 Industrie Alimentaire Résumé :
To manage the seasonal production surplus of figs, some families and cooperatives resort to the traditional processing. The impact of these traditional processes has not been sufficiently addressed by the literature. An important challenge is therefore to determine how to effectively preserve the antioxidant content of fruits from harvesting until consumption. In this context, the objectives of this thesis are: (i) to know the traditional methods of drying figs in the sun and the preparation of jam based on figs; (ii) the physicochemical characterization of fresh and dried figs and fig jams; (iii) the study of the bioaccessibility of phenolic compounds and their antioxidant activity during in vitro gastrointestinal digestion, while taking into account the varietal effect and the effect of sun drying. The varieties treated in this study are Aberkane, Azanjar and Taamriwt. To achieve these objectives, initially a survey was carried out in the Bejaia, Jijel, Skikda and Guelmaa cities. The survey showed that traditional drying and artisanal preparation of jam are the most widely used methods for preserving figs. The determination of the levels of phenolic compounds (total polyphenols, total flavonoids and total anthocyanins) was carried out by colorimetric methods. The evaluation of the antioxidant and anti-free radical potential was estimated in vitro by four tests (ABTS, DPPH, CUPRAC and FRAP). High performance diode array detector liquid chromatography (HPLC-DAD) was used to determine the phenolic profile of the various fig samples. The results indicated that the sun drying of figs and the preparation of jam have had a different influence on the physicochemical characteristics of figs. The levels of some phenolic compounds are negatively influenced by sun drying and processing into jam. Very considerable losses vary from 52.02 to 61.58% for sun-dried figs and from 52.21 to 69.38% for figs processed into jam. The two traditional processes applied also seem to negatively influence the antioxidant capacity. Likewise, positive correlations have been noted between antioxidant activity and the levels of phenolic compounds in dried figs and prepared jams. The static model of Minekus et al. (2014) of in vitro gastrointestinal digestion is used to study the bioaccessibility of phenolic compounds and their antioxidant activity. The content of phenolic compounds and the antioxidant capacity of fresh and dried figs obtained before digestion are significantly (p < 0.05) higher than those obtained after digestion. A significant decrease (p < 0.05) in the levels of phenolic compounds and their antioxidant activity was observed during the different phases of digestion (oral phase > gastric phase > intestinal phase). During in vitro gastrointestinal digestion, the varietal and drying effects are not significant on the phenolic compounds and on their antioxidant activity. Likewise, fresh and dried figs retained a high content of these compounds after digestion.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/KEH7848.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11831 Savoirs traditionnels sur le séchage au soleil et la préparation de confiture de figues et effets sur la teneur, le profil, l’activité antioxydante et la bioaccessibilité in vitro des composés phénoliques. [texte imprimé] / Farida Kehal, Auteur ; Malika Barkat, Directeur de thèse . - 04/01/2022 . - جامعة الإخوة منتوري قسنطينة, 2022 . - 204 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Technologies Alimentaires: Sciences Alimentaires Figues confiture séchage au soleil traditionnelle composés phénoliques activité antioxydante bioaccessibilité digestion gastro-intestinale in vitro Figs jam sun drying traditional phenolic compounds antioxidant activity bioaccessibility in vitro gastrointestinal digestion التين المربى التجفيف الشمسي المركبات الفينولية نشاط مضادات الأكسدة إمكانية الوصول
الحيوي الهضم المخبريIndex. décimale : 640 Industrie Alimentaire Résumé :
To manage the seasonal production surplus of figs, some families and cooperatives resort to the traditional processing. The impact of these traditional processes has not been sufficiently addressed by the literature. An important challenge is therefore to determine how to effectively preserve the antioxidant content of fruits from harvesting until consumption. In this context, the objectives of this thesis are: (i) to know the traditional methods of drying figs in the sun and the preparation of jam based on figs; (ii) the physicochemical characterization of fresh and dried figs and fig jams; (iii) the study of the bioaccessibility of phenolic compounds and their antioxidant activity during in vitro gastrointestinal digestion, while taking into account the varietal effect and the effect of sun drying. The varieties treated in this study are Aberkane, Azanjar and Taamriwt. To achieve these objectives, initially a survey was carried out in the Bejaia, Jijel, Skikda and Guelmaa cities. The survey showed that traditional drying and artisanal preparation of jam are the most widely used methods for preserving figs. The determination of the levels of phenolic compounds (total polyphenols, total flavonoids and total anthocyanins) was carried out by colorimetric methods. The evaluation of the antioxidant and anti-free radical potential was estimated in vitro by four tests (ABTS, DPPH, CUPRAC and FRAP). High performance diode array detector liquid chromatography (HPLC-DAD) was used to determine the phenolic profile of the various fig samples. The results indicated that the sun drying of figs and the preparation of jam have had a different influence on the physicochemical characteristics of figs. The levels of some phenolic compounds are negatively influenced by sun drying and processing into jam. Very considerable losses vary from 52.02 to 61.58% for sun-dried figs and from 52.21 to 69.38% for figs processed into jam. The two traditional processes applied also seem to negatively influence the antioxidant capacity. Likewise, positive correlations have been noted between antioxidant activity and the levels of phenolic compounds in dried figs and prepared jams. The static model of Minekus et al. (2014) of in vitro gastrointestinal digestion is used to study the bioaccessibility of phenolic compounds and their antioxidant activity. The content of phenolic compounds and the antioxidant capacity of fresh and dried figs obtained before digestion are significantly (p < 0.05) higher than those obtained after digestion. A significant decrease (p < 0.05) in the levels of phenolic compounds and their antioxidant activity was observed during the different phases of digestion (oral phase > gastric phase > intestinal phase). During in vitro gastrointestinal digestion, the varietal and drying effects are not significant on the phenolic compounds and on their antioxidant activity. Likewise, fresh and dried figs retained a high content of these compounds after digestion.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/KEH7848.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11831 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KEH/7848 KEH/7848 Thèse Bibliothèque principale Thèses Disponible
Titre : Utilisation de l’huile essentielle de Citrus limon comme agent conservateur et aromatique dans la crème fraîche Type de document : texte imprimé Auteurs : Farida Kehal, Auteur ; M Barkat, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 104 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Crème fraîche levures bactéries huile essentielle écorce de citron analyse sensorielle Cream yeast bacteria essential oil lemon zest sensory analysis القشدة الطازجة الخمائر البيكتيريا الزيوت الأساسية قشور الليمون التحاليل الحسية Index. décimale : 640 Industrie Alimentaire Résumé :
This study was conducted in order to enhance the lemon peel (Citrus limon) by using their essential oil as a natural agent for preservation and aromatization in cream in order to diversify the types of
existing cream on the market.
This essential oil was extracted by hydroditillation, extraction yield was 0,89 ± 0,09%. The antioxidant activity of the extracted essential oil was studied by the DPPH° test, this free radical has been effectively reduced, compared to vitamin E. These results were confirmed by the test of β- carotene bleaching.
The study of antimicrobial activity of essential oil of C. limon showed that two tested bacteria are resistant against the effectiveness of the oil, resulting in very high MICs (4% and > 8%). Regarding yeast strains isolated and tested Debaryomyces sp. and Rhodotorula sp., they have some sensitivity
to the effect of essential oil, characterized by CMI respectively 0,25% and 0,5%. The other two strains Zygosaccharomyces sp1 and Zygosaccharomyces sp2, were resistant, their MICs are respectively in the order of 1% and > 4%.
The various tests on the formulation of the added essential oil of C. limon creams were tested by developing three fresh creams with concentrations of 0,125%, 0,25%, 0,5%. Characteristics are conforms to standard. The results of physicochemical and microbiological analyzes prepared fresh cream after opening the package, show that the presence of the essential oil at low concentrations does not limit microbial spoilage. The evaluation of the oxidative stability by Schaal test indicates that the fresh cream with essential oil of C. limon are more resistant than the control opposite the forced oxidation.
Sensory analysis show that the incorporation of essential oil in the cream, at concentrations of 0,125% and 0,25%, involves no significant difference (p > 0,05) in terms of flavoring, and make products which are classified in same order than the control. Only the rate of incorporation of the essential oil of 0,5% significantly downgraded the product compared to the control in the third row, which has led to changes in smell and flavor while the texture, color and taste are unchanged. The principal component analysis (PCA) showed a negative correlation (r = - 0,998) between the levels of incorporation of the essential oil and the aroma of raw milk, and a positive correlation (r = 0,956) with the color yellow.Diplôme : Magistère En ligne : ../theses/agronomie/KEH6360.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6352 Utilisation de l’huile essentielle de Citrus limon comme agent conservateur et aromatique dans la crème fraîche [texte imprimé] / Farida Kehal, Auteur ; M Barkat, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2013 . - 104 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Crème fraîche levures bactéries huile essentielle écorce de citron analyse sensorielle Cream yeast bacteria essential oil lemon zest sensory analysis القشدة الطازجة الخمائر البيكتيريا الزيوت الأساسية قشور الليمون التحاليل الحسية Index. décimale : 640 Industrie Alimentaire Résumé :
This study was conducted in order to enhance the lemon peel (Citrus limon) by using their essential oil as a natural agent for preservation and aromatization in cream in order to diversify the types of
existing cream on the market.
This essential oil was extracted by hydroditillation, extraction yield was 0,89 ± 0,09%. The antioxidant activity of the extracted essential oil was studied by the DPPH° test, this free radical has been effectively reduced, compared to vitamin E. These results were confirmed by the test of β- carotene bleaching.
The study of antimicrobial activity of essential oil of C. limon showed that two tested bacteria are resistant against the effectiveness of the oil, resulting in very high MICs (4% and > 8%). Regarding yeast strains isolated and tested Debaryomyces sp. and Rhodotorula sp., they have some sensitivity
to the effect of essential oil, characterized by CMI respectively 0,25% and 0,5%. The other two strains Zygosaccharomyces sp1 and Zygosaccharomyces sp2, were resistant, their MICs are respectively in the order of 1% and > 4%.
The various tests on the formulation of the added essential oil of C. limon creams were tested by developing three fresh creams with concentrations of 0,125%, 0,25%, 0,5%. Characteristics are conforms to standard. The results of physicochemical and microbiological analyzes prepared fresh cream after opening the package, show that the presence of the essential oil at low concentrations does not limit microbial spoilage. The evaluation of the oxidative stability by Schaal test indicates that the fresh cream with essential oil of C. limon are more resistant than the control opposite the forced oxidation.
Sensory analysis show that the incorporation of essential oil in the cream, at concentrations of 0,125% and 0,25%, involves no significant difference (p > 0,05) in terms of flavoring, and make products which are classified in same order than the control. Only the rate of incorporation of the essential oil of 0,5% significantly downgraded the product compared to the control in the third row, which has led to changes in smell and flavor while the texture, color and taste are unchanged. The principal component analysis (PCA) showed a negative correlation (r = - 0,998) between the levels of incorporation of the essential oil and the aroma of raw milk, and a positive correlation (r = 0,956) with the color yellow.Diplôme : Magistère En ligne : ../theses/agronomie/KEH6360.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6352 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KEH/6360 KEH/6360 Thèse Bibliothèque principale Thèses Disponible
