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Gibberellins pre-treatment and storage at high relative humidity improved the quality of 'Eureka' lemon (Citrus limon (L.) Burm. f.) Texte intégral
2024
Dandan Li | Xihong Li | Ze Miao | Jin Du | Jinxiao Cheng | Shiting Hu | Yuhang Li | Yingying Zhang | Lingling Liu | Amr Farouk | Lu Li | Yuqian Jiang
The loss of pericarp greenness, wrinkling of the pericarp, and alteration of aroma are indicators of the ripening and senescence of lemons. In this study, lemons were soaked in 100 mg∙L-1 of gibberellin (GA) solutions for 5 min and stored at 14°C for 36 d under three relative humidity (RH) levels of 30%, 60%, and 90%, respectively. The changes in visual appearance, pigment metabolism, pericarpic microstructure, and volatile compounds of lemons during storage were evaluated. The results showed that GA pretreatment inhibited the color transformation from green to yellow of the flavedo and restrained fruit senescence. In addition, RH 90% effectively maintained the structural integrity of the oil gland, waxes, and stomata in the flavedo. GAs + RH 90% treatment maintained the fruit color index (L*, a*, b*, a*/b*, H°, C*) by inhibiting chlorophyll degradation and regulating carotenoid biosynthesis. Green lemons treated with GAs + RH 90% also showed reduced epidermal wrinkling, well-preserved cuticle, and stomatal structure, with a smooth and intact wax layer on the lemon pericarp. In addition, GAs + RH 90% treatment maintained the content of volatile aroma compounds, especially terpene. GAs + RH 90% had a great advantage in maintaining visual quality, delaying the deformation of tissue microstructure, preserving nutritional quality, and improving aroma. Thus, this treatment is potentially applicable for maintaining the storage quality of green lemons and extending their shelf life.
Afficher plus [+] Moins [-]The optimal precise temperature alleviated chilling injury and maintained post-harvest quality for 'Mengzi' pomegranate fruit Texte intégral
2024
Limei Li | Jinshan Luo | Xihong Li | Lingling Pang | Xiaoyu Jia | Lingling Liu | Miroslava Kačániová | Jitian Song | Liping Qiao
Chilling injury (CI) is a highly common physiological disorder in pomegranates during cold storage. Although several approaches have been investigated to mitigate the CI symptoms among some pomegranate cultivars, the fundamental and crucial environmental factor — the precise storage temperature for the 'Mengzi' cultivation remains unknown. This research evaluated the impact of storage temperatures of 0, 1, 2, 3, and 4 °C on the post-harvest quality of pomegranates. Results indicated that pomegranates stored at 2 °C exhibited the slightest color change and browning index. After storage of 130 d, pomegranates stored at 2 °C exhibited the lower CI index (82.79% reduction) and the lowest decay incidence (24.68% reduction) compared to those stored at 0 °C. The respiratory rate of pomegranates (2 °C) was also evidently suppressed (16.60%), along with a reduction in weight loss (3.46%). Furthermore, pomegranates stored at 2 °C exhibited the lowest activities of polyphenol oxidase (PPO) and peroxidase (POD), accompanied by the highest total phenolic content, which contributed to a reduction in malondialdehyde (MDA) accumulation. Relatively higher concentrations of soluble solids and titratable acid, as well as a higher sensory evaluation, were found in pomegranates stored at 2 °C. Consequently, it was inferred that the optimal temperature maintained cell membrane integrity modulated normal respiratory metabolism, and oxidative balance, and therefore alleviated CI and deterioration. This report can provide the guiding significance for the long-term storage of 'Mengzi' pomegranates under the condition of precise temperature control in phase temperature storage.
Afficher plus [+] Moins [-]Changes in the physicochemical and volatile profiles during the winemaking of Marselan in the Eastern Foot of Helan Mountain, China Texte intégral
2024
Lei Fang | Ningli Qi | Yajun Li | Tinghui Chen | Xiao Gong
Marselan wine, one of the most important wines in the Ningxia Hui Autonomous Region of China, has attracted much attention due to its unique quality. This study focused on determining and analyzing the changes in volatile flavor compounds and antioxidant activity during different stages of Marselan winemaking. A total of 40 volatile aroma compounds were identified by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). Among these compounds, ethyl hexanoate, isoamyl acetate, ethyl formate, ethyl acetate, ethyl butanoate, ethyl octanoate, 3-methyl-1-butanol, ethanol, and 2-methyl-1-propanol showed significant increases after fermentation. Flavonoid and phenol contents in Marselan wine samples also significantly increased after fermentation, demonstrating high antioxidant capacity. Principal component analysis (PCA) successfully distinguished the fruit juice processing stage, alcohol fermentation stage, and malolactic fermentation stage, while the malolactic fermentation stage and wine stable stage could not be distinguished, This indicates that the formation of aroma profiles primarily occurs during the malolactic fermentation stage. The study successfully established flavor fingerprints of samples from different stages of Marselan wine production based on the detected volatile compounds.
Afficher plus [+] Moins [-]Emulsification stability of Auricularia auricula polysaccharides and its effect on steady-state properties of β-carotene embedding Texte intégral
2024
Xiaqing Lv | Dexi Zhang | Xiangyang Zhu | Dapeng Li | Chen Zhang
The objective of the study was to examine the physicochemical properties and emulsification stability of three different Auricularia auricula polysaccharides (AAP) obtained through hot water extraction (AAP-W), hot acid extraction (AAP-A), and hot alkaline extraction (AAP-AL), respectively. The findings indicated that AAP-W exhibited superior emulsification stability compared to the other two polysaccharides. AAP-W was employed as a natural emulsifier for emulsion preparation, to examine the influence of varying polysaccharide concentrations and oil-water ratios on emulsion stability. Additionally, an investigation was conducted into the stability of the emulsions with respect to pH and salt ion concentration. The findings revealed that the most favorable polysaccharide concentration for the AAP-W emulsion was determined to be 1%, while the volume fraction of the oil phase was established at 0.5. It was also observed that the emulsion exhibited robust stability even in challenging conditions characterized by strong acidic (pH 3−5) or basic environments (pH 9−11), as well as high concentrations of salt ions (0−500 mM). Furthermore, the construction of an AAP-W emulsion system incorporating β-carotene was undertaken to enhance the preservation, bioavailability, and digestive stability of β-carotene, thereby expanding the potential applications of Auricularia auricula polysaccharides. This endeavor also presents a novel approach towards the advancement of novel functional food products.
Afficher plus [+] Moins [-]Role of the gut microbiota in liver diseases | Role of the gut microbiota in liver diseases: Attestation from microbiota transplants in germfree animal models Texte intégral
2024
Gerard, Philippe | MICrobiologie de l'ALImentation au Service de la Santé (MICALIS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | MICrobiologie de l'ALImentation au Service de la Santé (MICALIS) ; AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Institut des Sciences Vétérinaires, El- Khroub, Université de Constantine 1
International audience | The human intestine is home to a complex bacterial community known as the gut microbiota. This microbiota performs functions that are essential for maintaining our health, and has been shown to influence the host's physiology and metabolism. As a result, dysregulation of this intestinal microbiota, known as dysbiosis, could be implicated in the development of various diseases. However, studies analysing the microbiota rarely assess causality, which can be demonstrated by using germ-free (GF) animals and transplanting microbiota. Using these strategies, it has been shown that the intestinal microbiota may play a causal role in the development of obesity and associated metabolic disorders, particularly liver diseases, including Metabolic dysfunction–associated steatotic liver disease (MASLD) and Alcoholic liver disease (ALD). Indeed, by transplanting the gut microbiota from mice with or without MASLD to GF mice, we showed that the propensity to develop MASLD features including hyperglycaemia or steatosis is transmissible by the gut microbiota. Regarding ALD, we first showed that a specific dysbiosis is present in alcoholic patients with a severe alcoholic hepatitis. GF mice colonized with the gut microbiota from a patient with severe alcoholic hepatitis (AH) developed more severe liver inflammation and higher liver necrosis, than GF mice colonized with the gut microbiota from an alcoholic patient without AH.In conclusion, we demonstrated that the individual susceptibility to liver diseases is driven, at least partly, by differences in intestinal microbiota composition. Our findings open new avenues for diagnostic procedures based on personalised medicine by the identification of patients at high risk of developing liver diseases. They also open new possibilities for liver diseases prevention and treatment through intestinal microbiota manipulation.
Afficher plus [+] Moins [-]Effects of a Mealworm Larvae-Based Diet on Laying Performance and Egg Quality in Laying Hens in Algeria | Effets d'un Régime à Base de Larves de Vers de Farine sur la Performance de Ponte et la Qualité des Œufs chez les Poules Pondeuses en Algérie Texte intégral
2024
Moula, Nassim
peer reviewed | Soybean is a crucial component of animal feed, especially for poultry and monogastric animals, because of its high protein and amino acid content. However, dependence on soybeans—particularly imported varieties—poses challenges, including price volatility and concerns regarding GMOs. Organic farming, which prohibits GMOs, faces even higher costs to source non-GMO soybean meal. To address these issues, alternative protein sources such as insects are attracting interest. Insects provide a rich supply of proteins, fats, vitamins, and minerals, offering a sustainable substitute for both soybean and fishmeal. Key insect candidates for feed include the black soldier fly, housefly, and yellow mealworm (Tenebrio molitor, TM). Research indicates that insect meal can replace traditional feed sources without reducing productivity. This study, conducted at a poultry farm in Chemini, Bejaia, Algeria, examined 36 Isa-Brown laying hens, 40 weeks old. The hens were divided into 12 pens (3 control and 9 experimental), with experimental groups receiving feed supplemented with 1% (TM1), 2% (TM2), or 4% (TM4) mealworms. Over a four-week period, egg quality (physical and chemical properties) and feed conversion efficiency were evaluated. Data analysis, performed using SAS software with a significance threshold of P<0.05, revealed no significant differences in laying rates (P=0.48), although the TM4 group showed a slightly lower rate. However, TM4 achieved the best feed conversion ratio (P=0.03). Egg quality parameters, including weight and shell characteristics, remained consistent across all groups, with no significant differences in cholesterol or essential fatty acids. Incorporating mealworms into poultry feed thus appears to improve feed efficiency while maintaining egg quality, although there was a slight reduction in laying performance at higher inclusion rates. The relatively small sample size, however, limits the generalizability of these findings. | Le soja est un composant essentiel de l'alimentation animale, en particulier pour la volaille et les animaux monogastriques, en raison de sa teneur élevée en protéines et en acides aminés. Cependant, la dépendance au soja – en particulier aux variétés importées – pose des défis, notamment en termes de volatilité des prix et de préoccupations liées aux OGM. L’agriculture biologique, qui interdit les OGM, se heurte à des coûts encore plus élevés pour se procurer du tourteau de soja non-OGM. Afin de résoudre ces problèmes, des sources alternatives de protéines, telles que les insectes, suscitent de plus en plus d'intérêt. Les insectes offrent un apport riche en protéines, lipides, vitamines et minéraux, constituant une alternative durable au soja et à la farine de poisson. Parmi les insectes les plus prometteurs pour l’alimentation animale figurent la mouche soldat noire, la mouche domestique et le ver de farine jaune (Tenebrio molitor, TM). La recherche indique que la farine d'insectes peut remplacer les sources d'alimentation traditionnelles sans diminuer la productivité. Cette étude, menée dans une ferme avicole à Chemini, Béjaïa, en Algérie, a examiné 36 poules pondeuses Isa-Brown âgées de 40 semaines. Les poules ont été réparties dans 12 enclos (3 enclos témoins et 9 expérimentaux), les groupes expérimentaux recevant un aliment enrichi en vers de farine à raison de 1 % (TM1), 2 % (TM2) ou 4 % (TM4). Sur une période de quatre semaines, la qualité des œufs (caractéristiques physiques et chimiques) et l'efficacité de conversion alimentaire ont été évaluées. L'analyse des données, effectuée à l'aide du logiciel SAS avec un seuil de signification de P<0,05, n'a révélé aucune différence significative dans les taux de ponte (P=0,48), bien que le groupe TM4 ait montré un taux légèrement inférieur. Cependant, le groupe TM4 a obtenu le meilleur indice de conversion alimentaire (P=0,03). Les paramètres de qualité des œufs, y compris le poids et les caractéristiques de la coquille, sont restés constants dans tous les groupes, sans différences significatives au niveau du cholestérol ou des acides gras essentiels. L'incorporation de vers de farine dans l'alimentation des poules pondeuses semble donc améliorer l'efficacité alimentaire tout en maintenant la qualité des œufs, bien qu'une légère réduction de la performance de ponte ait été observée aux taux d'inclusion les plus élevés. Toutefois, la taille relativement réduite de l'échantillon limite la généralisation de ces résultats. | يُعتبر فول الصويا مكونًا أساسيًا في تغذية الحيوانات، وخاصةً الدواجن والحيوانات أحادية المعدة، نظرًا لمحتواه العالي من البروتين والأحماض الأمينية. ومع ذلك، فإن الاعتماد على فول الصويا – خاصةً الأصناف المستوردة – يطرح تحديات، بما في ذلك تقلب الأسعار والمخاوف المتعلقة بالكائنات المعدلة وراثيًا (OGM). كما تواجه الزراعة العضوية، التي تحظر استخدام الكائنات المعدلة وراثيًا، تكاليف أعلى للحصول على كُسب فول الصويا غير المعدل وراثيًا. وللتغلب على هذه المشكلات، تكتسب مصادر البروتين البديلة، مثل الحشرات، اهتمامًا متزايدًا. فالحشرات تُقدم مصدرًا غنيًا بالبروتينات والدهون والفيتامينات والمعادن، مما يجعلها بديلاً مستدامًا لفول الصويا وطحين السمك. ومن بين الحشرات الواعدة لتغذية الحيوانات نجد الذبابة الجندية السوداء، وذبابة المنزل، ودودة الطحين الصفراء (تينبريو موليتور، TM). وتشير الأبحاث إلى أن طحين الحشرات يمكنه استبدال المصادر الغذائية التقليدية دون التأثير على الإنتاجية. أُجريت هذه الدراسة في مزرعة دواجن بمنطقة شَمّيني، ولاية بجاية، الجزائر، واشتملت على 36 دجاجة بياضة من نوع Isa-Brown بعمر 40 أسبوعًا. تم توزيع الدجاجات على 12 حظيرة (3 حظائر كمجموعة ضابطة و9 حظائر كمجموعات تجريبية)، حيث تلقت المجموعات التجريبية علفًا مُضافًا إليه ديدان الطحين بنسبة 1% (TM1)، 2% (TM2) أو 4% (TM4). وعلى مدار فترة أربعة أسابيع، تم تقييم جودة البيض (الخصائص الفيزيائية والكيميائية) وكفاءة تحويل العلف. أظهرت نتائج التحليل الإحصائي، الذي أُجري باستخدام برنامج SAS مع مستوى دلالة P<0.05، عدم وجود فروق ذات دلالة إحصائية في معدلات البيض (P=0.48)، على الرغم من أن مجموعة TM4 أظهرت معدلًا أقل قليلًا. ومع ذلك، حققت مجموعة TM4 أفضل معدل تحويل غذائي (P=0.03). بقيت خصائص جودة البيض، بما في ذلك الوزن وخصائص القشرة، متناسقة بين جميع المجموعات دون فروق ذات دلالة إحصائية في مستويات الكوليسترول أو الأحماض الدهنية الأساسية. يبدو أن إدماج ديدان الطحين في علف الدجاج البياض يحسن كفاءة التغذية مع الحفاظ على جودة البيض، رغم حدوث انخفاض طفيف في أداء وضع البيض عند معدلات الإضافة الأعلى. ومع ذلك، فإن حجم العينة الصغير نسبيًا يحد من إمكانية تعميم هذه النتائج.
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