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1.
Nutritional warnings are rapidly gaining relevance, particularly in the region of the Americas, as a front-of-package nutrition labelling scheme that facilitate the identification of products with high content of nutrients associated with non-communicable diseases (NCDs). Several graphic designs are being developed as countries discuss the implementation of nutritional warnings, which makes it necessary to develop research to evaluate their efficacy. In this context, the aim of the present work was to compare the efficacy of a series of nutritional warnings that are being considered by Brazilian national authorities for the country with two of the most studied schemes: the guidelines daily amounts (GDA) and the traffic light system. Two studies were conducted. In the first one, visual search was conducted with 62 participants to evaluate the time needed by them to identify the schemes on food labels and to identify whether a product had high nutrient content. In the second study, an online survey with 1932 participants was used to evaluate their ability to use FOP nutrition labelling schemes to correctly identify the most healthful product in a set, as well as high nutrient content in a product. In addition, the influence of FOP nutrition labelling schemes on perceived healthfulness was evaluated. Finally, consumers’ perception of the schemes was gathered using an open-ended question. Results confirmed the advantages of nutritional warnings compared to the GDA and the traffic-light system to facilitate the identification of products with high content of nutrients associated with NCDs. In addition, the use of familiar signs frequently used to convey a ‘warning message’ outperformed other unfamiliar signs in terms of their ability to facilitate the interpretation of nutrition information. Regarding colour, black signs tended to required significantly less time to be detected when included on colour food labels compared to red signs.  相似文献   
2.
对G1n小肽在氨基酸营养液中的使用以及G1n小肽的稳定性和代谢机制进行了论述。G1n是一种“条件必需氨基酸”,但Cln的水溶液不稳定,因而在氨基酸输液或氨基酸营养被中,用G1n小肽代替G1n单体使用。G1n小肽含有取代的α—NH2,使Cln小肽的稳定性大大增加。  相似文献   
3.
烹饪工艺与营养专业的校内经营是通过学院提供校园餐厅,在课堂内完成专业培养方案的教学任务,组织学生进入校园餐厅顶岗实训,形成教学经营一体化校内经营运行模式。文章阐述了校内经营教学模式的基本思路、校内餐厅的要求和管理,总结了校内经营模式运行过程中出现的问题,并针对如何进一步完善校内经营模式提出新思路。  相似文献   
4.
The production of crab meatballs generates large amount of crab shell waste, it is therefore necessary to develop a green, economical and environmentally friendly process to vaporize the waste. This study was aimed at investigating the applicability of microwave heating combined with ultrasonic field-assisted alkaline protease (MUSED) (50 ℃, pH = 9.0, 14025.67 U/g, 4.21 h and liquid/material = 14.41:1) for pretreatment of ball-milled crab shells. The ball milling efficiency of the crab shell powder pretreated by MUSED was observed to increase by 50 % compared to the control group, with the final average particle size of D4 = 4.88 ± 0.20 um. High calcium solubility and low energy consumption of the ball-milled powder increased dietary calcium bioavailability and reduced the potential for high calorie intake. The addition of 6 % (w/w) crab shell powder treated by MUSED improved the texture of the crab meatballs (CM-D4) and gave the product enhanced crab flavor relative to the control group. Moreover, the lower cooking loss of CM-D4 resulted in significant retention of nutrients (p < 0.05). The crab shell powder treated by MUSED method was more efficient in ball milling, which improved the quality of crab meatballs while relieving environmental pressure.  相似文献   
5.
冬小麦红边参数变化规律及其营养诊断   总被引:21,自引:1,他引:21  
研究了冬小麦冠层光谱红边参数随作物生育期的变化规律,并进行了红边参数与各组分间的相关分析,发现可利用用红边位置反演叶片可溶性糖和叶绿素含量,利用红边振幅反演叶片全氮含量,利用红谷反演叶面积指数。建立了基于红边参数的各组分的统计回归模型,可为生产上利用遥感手段大面积、无破坏、及时评价冬小麦生长状态及营养诊断提供重要依据。  相似文献   
6.
This study evaluated and correlated the viscoelastic and nutritional properties of carrots after freezing (–20, –70, and –196oC) and thawing (4 and 18oC) treatments. Results showed that all samples exhibited a solid behavior (storage modulus G′ > loss modulus G″) dominating the viscoelastic response. After treatments, G′, G″, hardness, fracturability, springiness, and chewiness of carrots significantly decreased, whereas loss tangent (Tanδ) increased. Compared with other treatments, fast freezing (–196oC) and thawing (18oC) better maintained G′, G″, hardness, and fracturability of carrots, and intermediate freezing (–70oC) better retained springiness, cohesiveness, and chewiness. For nutritional parameters, fast freezing and thawing conditions also contributed to preserving the contents of carotenoids of carrots. Partial least squares regression analysis revealed that β- and α-carotene, lycopene, and soluble sugars were positively correlated with hardness, fracturability, G′, and G″, and negatively with Tanδ in carrots. The variation of viscoelastic parameters could well predict the changes at nutritional levels.  相似文献   
7.
Food selection at a particular occasion is guided by properties of the food itself (sensory or intrinsic properties), but also by the information provided with the food, for example, packaging information (extrinsic properties). We compared preference responses of 71 consumers with a considerable type 2 diabetes risk, who had undergone nutrition counseling in a prevention program, in sensory assessments and product evaluation integrated into Adaptive Conjoint Analysis with the response of a healthy control group (n = 101). Vanilla yogurt, varied in composition (fat content, sugar content, flavor intensity) and packaging information (fat content, sugar content, flavor intensity), was used as stimulus material. Both groups of consumers preferred yogurt with a higher fat content on the basis of sensory evaluation, but rejected products with a higher fat content (10 g/100 g) when this information was available on the package. The degree of rejection was significantly higher for the high risk group. Whereas both groups preferred reduced-sugar yogurt on the basis of declaration, preferences towards the less sweet product were only observed for the high risk group.  相似文献   
8.
BackgroundZein, a byproduct of corn with renewable resources, unique hydrophobic/hydrophilic character, film/fiber forming and antioxidant properties, is a promising biopolymer for food and nutrition applications. The advantages in properties and efficiencies of nano materials over bulk counterparts are the basis of their unique nature in novel technologies. These advantages also expand their possible applications.Scope and approachAn effort has been made to review on applications of zein/zein-based nano-materials in various branches of food (except food packaging) and nutrition sectors. The effects of various parameters affecting preparations and properties of the nano-materials are also discussed. Nano-encapsulation of foods and nutrients is the major section of this study.Key findings and conclusions(i) the average size of zein nanoparticles reported to be 50–200 nm; (ii) the functions of zein nanomaterials were multiples: a carrier of delivery (food, beverage, and nutrient) systems; a shell or a core of encapsulated systems; or a food ingredient; (iii) zein-based nano-materials have been used for encapsulation of food and nutrient components including lipids; essential oils; fat soluble vitamins; food colorants; flavors; and natural anti-oxidants; (iv) the bioavailability of food and nutrient components such as folic acid, vitamin D3, curcumin, beta-carotene, and resveratrol was improved by employing the zein-nanoparticles in comparison with the bulk counterparts; and (v) bioactive substances with potential applications for food and nutrition sectors were stabilized by zein/zein-based nano-materials.  相似文献   
9.
The impact of internet use on food and nutrition security of rural households in Ghana is investigated in this study. To offset the potential challenge of selection bias, an endogenous treatment regression (ETR) technique is utilized for the analysis.. The results reveal that Internet use can improve smallholder farmers’ food and nutrition security. Internet usage has a profound positive effect on the food security of households with off-farm work and larger size of landholding. Our results suggest the intensification of efforts to enhance Internet connectivity across the nation by the government and policymakers is essential since it can go a long way to affect household welfare. The findings also highlight the importance of information and communication technologies (ICTs), the Internet, patronization to improve rural household welfare.  相似文献   
10.
A methodology for assessing attention to and effect of nutrition information displayed front-of-pack is presented. The methodology is based on an integration of the visual search paradigm, the choice paradigm and eye-tracking measures, and moves beyond reliance on self-report measures for attention and choice. Rather the following measures are obtained: (1) respondents’ eye-movements, in terms of dwell time, fixation duration, number of fixations, and saccade size; (2) response times indicating the speed with which choice decisions are made; and (3) consumers’ actual choices from an assortment. The efficiency and sensitivity of the methodology is illustrated in a small scale empirical application. Overall, the methodology seems to be a promising tool for answering puzzling questions in consumer attention and decision making with straightforward potential extensions to enlarge its scope.  相似文献   
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