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21.
在提出土壤养分有效性测定概念的基础上 ,本文对各种土壤养分有效性的测定方法进行了总结 ,讨论了这些方法的测定机理、测定效果及近几年的进展。这些方法包括用于磷钾等元素测定的树脂法、用于氮测定的生物培养法和化学提取法、磷测定的氧化铁试纸法和氢氧化铁透析管法和钾的四苯硼钠法 相似文献
22.
硅作为重要的植物营养元素,近年来越来越受到人们的关注。本文从植物对硅的吸收及硅在植物体内的输送和分布、硅素在提高植物抗病虫害能力和增强植物抗逆性上的作用、影响土壤硅素肥力的因素以及硅素肥料的施用技术等几个方面,对土壤硅素肥力及植物硅素营养的研究进展进行了综述,并对今后一段时间该领域的研究趋势做了展望。 相似文献
23.
ADSA Foundation Scholar Award: New frontiers in calf and heifer nutrition—From conception to puberty
J.K. van Niekerk A.J. Fischer-Tlustos J.N. Wilms K.S. Hare A.C. Welboren A.J. Lopez T.T. Yohe L.R. Cangiano L.N. Leal M.A. Steele 《Journal of dairy science》2021,104(8):8341-8362
Dairy calf nutrition is traditionally one of the most overlooked aspects of dairy management, despite its large effect on the efficiency and profitability of dairy operations. Unfortunately, among all animals on the dairy farm, calves suffer from the highest rates of morbidity and mortality. These challenges have catalyzed calf nutrition research over the past decade to mitigate high incidences of disease and death, and improve animal health, growth, welfare, and industry sustainability. However, major knowledge gaps remain in several crucial stages of development. The purpose of this review is to summarize the key concepts of nutritional physiology and programming from conception to puberty and their subsequent effects on development of the calf, and ultimately, future performance. During fetal development, developmental plasticity is highest. At this time, maternal energy and protein consumption can influence fetal development, likely playing a critical role in calf and heifer development and, importantly, future production. After birth, the calf's first meal of colostrum is crucial for the transfer of immunoglobulin to support calf health and survival. However, colostrum also contains numerous bioactive proteins, lipids, and carbohydrates that may play key roles in calf growth and health. Extending the delivery of these bioactive compounds to the calf through a gradual transition from colostrum to milk (i.e., extended colostrum or transition milk feeding) may confer benefits in the first days and weeks of life to prepare the calf for the preweaning period. Similarly, optimal nutrition during the preweaning period is vital. Preweaning calves are highly susceptible to health challenges, and improved calf growth and health can positively influence future milk production. Throughout the world, the majority of dairy calves rely on milk replacer to supply adequate nutrition. Recent research has started to re-evaluate traditional formulations of milk replacers, which can differ significantly in composition compared with whole milk. Transitioning from a milk-based diet to solid feed is critical in the development of mature ruminants. Delaying weaning age and providing long and gradual step-down protocols have become common to avoid production and health challenges. Yet, determining how to appropriately balance the amount of energy and protein supplied in both liquid and solid feeds based on preweaning milk allowances, and further acknowledging their interactions, shows great promise in improving growth and health during weaning. After weaning and during the onset of puberty, heifers are traditionally offered high-forage diets. However, recent work suggests that an early switch to a high-forage diet will depress intake and development during the time when solid feed efficiency is greatest. It has become increasingly clear that there are great opportunities to advance our knowledge of calf nutrition; yet, a more concentrated and rigorous approach to research that encompasses the long-term consequences of nutritional regimens at each stage of life is required to ensure the sustainability and efficiency of the global dairy industry. 相似文献
24.
精准营养与粮油健康食品的发展趋势 总被引:1,自引:0,他引:1
从健康中国2030主要指标、主要措施以及中国居民膳食指南建设3方面论述了健康中国是我国的重大发展战略;从营养健康食品的发展阶段、我国疾病谱发生转变及慢性非传染性疾病逐年上升、需求迫切食品营养科学与与系统化基础数据库支撑、全链条交叉融合创新发展正成为精准营养和粮油健康食品产业创新发展新模式等方面展望了精准营养健康食品的发展趋势;并提出了我国发展精准营养与健康食品的相关建议。 相似文献
25.
随着人们生活质量的提高,人们对于食物营养的要求也越来越高。由于花生酱的脂肪含量极高,不适于糖尿病、高血压等疾病的患者和老人食用,因此研发低脂、健康、营养的新型花生酱很重要。通过对花生酱制作工艺的调整,降低油脂含量以及补充或添加健康辅料,能显著改善花生酱的营养价值,这也成为花生酱营养改进的重要方向之一。本文对花生酱中脂肪、蛋白质等营养成分及新型花生酱的研究进展进行综述。未来新型花生酱的研发重点可能是通过原料筛选、增加添加剂、改善制作工艺等来调节肠道菌群平衡、增加其益生作用等方面。 相似文献
26.
Elif Celik 《Critical reviews in food science and nutrition》2019,59(1):102-113
Alzheimer's disease (AD) is the most common form of dementia in the elderly and is a chronic neurodegenerative disease that is becoming widespread. For this reason, in recent years factors affecting the development, progression and cognitive function of the AD have been emphasized. Nutrients and other bioactive nutrients are among the factors that are effective in AD. In particular, vitamins A, C and E, vitamins B1, B6 and B12, folate, magnesium, choline, inositol, anthocyanins, isoflavones etc. nutrients and bioactive nutrients are known to be effective in the development of AD. Nutrients and nutrient components may also have an epigenetic effect on AD. At the same time, nutrients and bioactive food components slow down the progression of the disease. For this reason, the effect of nutrients and food components on AD was examined in this review. 相似文献
27.
Hugh E. Lippman Jehan-François Desjeux Zong-Yi Ding Kraisid Tontisirin Ricardo Uauy Regina A. Pedro 《Critical reviews in food science and nutrition》2016,56(1):141-145
Utilization of expert recommendations in the development of food and beverage nutritional profiles represents an opportunity to merge science and food manufacturing to deliver nutritionally optimized products into the marketplace. This report details expert panel guidelines for the design of a nutritional product for children one to six years of age. This interaction demonstrates the essential synergy between academia and food manufacturers in translating nutrient recommendations to food for their delivery to a population. Important factors for such translation are the identification of applicable nutrient recommendations and selection of an appropriate delivery matrix. This report demonstrates the translation of expert nutritional recommendations to a milk-based product for children—one to six years of age. 相似文献
28.
Effect of clove extract pretreatment and drying conditions on lipid oxidation and sensory discrimination of dried omena (Rastrineobola argentea) fish
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Margaret Slavin Mengyi Dong Constance Gewa 《International Journal of Food Science & Technology》2016,51(11):2376-2385
Sun‐drying is a low‐cost, low‐technology fish preservation method frequently employed in developing areas. However, the process promotes lipid oxidation and its associated undesired flavours and odours. This study investigated low‐technology solutions for impact on lipid oxidation and sensory attributes of oven‐dried omena fish (Rastrineobola argentea). Two oven‐drying conditions and four doses of clove water extract ‘dip’ pretreatments were studied in a complete factorial design. Lipid oxidation in dried fish was assessed by TBARS, peroxide value and fatty acid analysis by GC‐FID. Results showed that soaking in 10 g L?1 clove water extract for 1 h and oven‐drying at 150 °C × 30 min significantly reduced TBARS and peroxide values in omena fish by 77% and 79%, respectively, and polyene index showed improved retention of long‐chain polyunsaturated fats, compared to original drying condition. Lastly, panellists of a triangle test were able to discriminate between biscuits made with the modified and original dried fish. 相似文献
29.
《Food and Foodways: Explorations in the History and Culture of》2012,20(4):316-337
AbstractWe utilized key informant interviews to examine traditional diet (TD) perceptions among members of the Hispanic Caribbean (HC) community in New York City (Dominicans, Cubans and Puerto Ricans, n?=?23). While the cuisines share many similarities, the interviews revealed differences in how the TDs were evaluated. Cubans emphasized the unhealthiness of their TD, while Dominicans and Puerto Ricans emphasized the importance of their TD in daily life. Participants identified unhealthy aspects of their TDs (predominance of carbohydrates and fried foods, and the lack of fresh fruits and vegetables), and discussed motivations for dietary changes (migration, the demands of new labor routines, health concerns, and spouse/family influence). The analysis demonstrates that distinct ideas, symbols, and meanings associated with TDs reflect how these communities relate to their heritage countries, as a result of distinct migration histories and global forces shaping cuisines and societies in the diaspora and the Caribbean. 相似文献
30.
Yuyu Wang Shiliang Yu Guojun Ma Songbo Chen Ye Shi Yuhong Yang 《International Journal of Food Science & Technology》2014,49(4):983-989
The proximate composition and amino acid compositions of the muscle of wild and farmed Pseudobagrus ussuriensis were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish. Pseudobagrus ussuriensis protein has a well‐balanced amino acid composition. The percentages of total amino acids, essential amino acids, nonessential amino acids and delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of WEAA to WTAA (42.78%–43.02%) and WEAA to WNEAA (85.52%–87.74%) were comparable to the reference values of 40% and above 60% recommended by FAO/WHO. According to the amino acid scores, methionine would have been described as the first limiting amino acid, and Lys had the highest score for the protein in both wild and farmed Pseudobagrus ussuriensis. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources. 相似文献