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61.
Cocoa butter equivalents (CBEs) are produced from vegetable fats by blending palm mid fraction (PMF) and tropical butters coming from shea, mango kernel or kokum fat. In this regard, high oleic-high stearic (HOHS) sunflower hard stearins from solvent fractionation can be used in CBE production since their compositions and physical properties are similar to those found in the above-mentioned tropical butters. In this work, three sunflower hard stearins (SHS) ranging from 65% to 95% of disaturated triacylglycerols and a shea stearin (used as reference) were blended with PMF to evaluate their potential use in CBEs formulation. Isosolid phase diagrams of mixtures of PMF/SHS showed eutectic formation for SHS 65 and SHS 80, but monotectic behaviour with softening effect for SHS 95. Three CBEs from SHS and shea stearin were formulated according to phase behaviour diagrams and solid fat content data at 25 °C. Isosolid phase diagrams of mixtures of these CBEs with cocoa butter showed no eutectic behaviour. Therefore, CBEs elaborated from SHS exhibited full compatibility with cocoa butter.  相似文献   
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Antimicrobial food packaging film based on the release of LAE from EVOH   总被引:1,自引:0,他引:1  
The aim of this work was to develop antimicrobial films for active packaging applications containing the natural antimicrobial compound LAE (lauramide arginine ethyl ester) in EVOH copolymers with different mol % ethylene contents (i.e. EVOH-29 and EVOH-44). EVOH-29 and EVOH-44 films were made by casting and incorporating 0.25%, 1%, 5%, and 10% LAE in the film forming solution (w/w with respect to polymer weight). Previously, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of LAE against Listeria monocytogenes, Escherichia coli, and Salmonella enterica were determined by a microdilution assay. The antimicrobial activity of the resulting films was tested in vitro against these microorganisms in liquid culture media. The activity of the films was also evaluated over time. The results showed that films containing 5% and 10% LAE produced total growth inhibition and viable counts decreased with 0.25% and 1% LAE. Finally, the effectiveness of the films was tested by applying them to an infant formula milk inoculated with L. monocytogenes and S. enterica and stored for 6 days at 4°C. The application of films with LAE to infant formula milk inoculated with L. monocytogenes reduced at the end of storage period about 4 log in case of 10% LAE and with S. enterica reduced 3.74 log and 3.95 log with EVOH 29 5% and 10%, respectively, and EVOH-44 5% and 10% LAE reduced 1 log and 3.27 log, respectively, at the end of storage. The antimicrobial capacity of EVOH-29 films was greater than that of EVOH-44 films in all the cases tested. In general, the films were more effective in inhibiting the growth of L. monocytogenes than S. enterica, this inhibition being more acute at the end of the storage time.  相似文献   
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Food Science and Biotechnology - The use of unconventional sources is very relevant in the food area. In the present study the development of active films with the addition of bioextract (BE) or...  相似文献   
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This work investigated the potential of NIR technology to be applied in the dairy industry for the detection of micro‐organisms. To this end, two types of cow milk samples were studied, one in which only bacterial biomass was considered and the other in which bacteria were cultured and grown in milk for 24 h. The study was carried out using two micro‐organisms Escherichia coli and Pseudomonas aeruginosa. Both types of samples with different counts of both micro‐organisms were analysed by a NIR analyser in the range 10 000–4000 cm?1 based on transmittance measurements. Multivariate models indicated that a better discrimination between micro‐organisms was attained in those milk samples in which micro‐organisms have been grown.  相似文献   
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Social media has experienced rapid growth in recent years and has been subjected of discussions on a wide range of topics including new lifestyles and eating habits, providing a great opportunity to obtain spontaneous consumer information. In this sense, the present work aimed to understand the perception of Twitter® users about themes of veganism and plant-based diets. The social networking data mining methodology was applied to measure the relationship between both terms. The significant differences found were analysed using the global chi-square (χ2) test, and their sources of variation were investigated by the chi-square per cell. The results indicate that the vegan group's posts are more related to the categories of recipes, trends, criticism and negative comments about veganism, being more often citing sources when compared to the other group. The results of the plant-based diet group are more significantly related to the impacts of nutrition, physical activity and consumer health. In conclusion, Twitter® has proved to be an interesting tool for obtaining data on (re) produced food publications on social media and their results can guide the market and the academic environment in creating new products, services and marketing strategies to answer the needs of specific consumers.  相似文献   
68.
This work investigated the deacidification of soybean oil by ion exchange using a fixed bed loaded with the strong anionic resin Amberlyst A26 OH. Degummed soybean oil was dissolved in isopropanol and the deacidification process was studied according to an experimental design based on two factors, the feed flow rate and its content of free fatty acids. The responses of interest were the solute recovery efficiency and the bed utilization efficiency, both calculated from breakthrough curves. Oil samples before and after deacidification by ion exchange, as well as samples deacidified in the industrial plant by the chemical method, were characterized according to the usual indexes for quality and identity. The results revealed that the flow rate was an important and statistically significant factor with 95 % of confidence. The deacidification by ion exchange decreased the oil acidity and also removed undesirable compounds, such as phospholipids and peroxides. However, a decrease in the concentration of tocopherol was also observed.  相似文献   
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