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81.
Busarakorn Mahayothee Patchimaporn Udomkun Marcus Nagle Methinee Haewsungcharoen Serm Janjai Joachim Mueller 《European Food Research and Technology》2009,229(2):329-337
The objective of this research was to study the effect of osmotic pretreatment with combined anti-browning agents (acid, glycerol
and/or trehalose) on the colour characteristics of dried litchi after drying and during 5 months of storage compared to samples
without pretreatment. The pretreated samples showed good inhibition of polyphenol oxidase activity when compared with the
control, while the total phenolic contents in the dried products were not reduced. The results demonstrated that water activity,
lightness difference, chroma, degree of browning (DB), and 5-hydroxymethylfurfural values of all pretreated samples increased,
while hue angle decreased with storage time. Samples pretreated with glycerol showed the best potential for browning retardation,
followed by glycerol combined with trehalose, and trehalose, respectively. In addition, the colour parameters were used to
calculate the luminescence values, representing the data in grey scale, which were correlated with a non-enzymatic browning
index. The results showed grey value could be adequately used to represent the DB of dried litchi with r
2 value of 0.92. 相似文献
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Ohne Zusammenfassung
The online version of the original article can be found at 相似文献
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Plasmaprimer — functional coatings for adhesion improvement When replacing solvent based paint or adhesion promoter partly new production processes are necessary. Plasma enhanced chemical vapor deposition offers to change the surface characteristics of parts according to the necessities of the following application. At the same time improvements in adhesion, in handling and environmental compatibility can be achieved. In this article an according production method is described and perspectives of new developments are shown. 相似文献
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Joachim J. Schouteten Hans De Steur Benedikt Sas Ilse De Bourdeaudhuij Xavier Gellynck 《Journal of dairy science》2017,100(1):169-186
Although sensory and emotional evaluation of food products mostly occurs in a controlled laboratory environment, it is often criticized as it may not reflect a realistic situation for consumers. Moreover, products are mainly blind evaluated by participants, whereas external factors such as brand are often considered as key drivers of food choice. This study aims to examine the role of research setting (central location test versus home-use test) and brand information on the overall acceptance, and sensory and emotional profiling of 5 strawberry-flavored yogurts. Thereby, private label and premium brands are compared under 3 conditions: blind, expected, and informed (brand information). A total of 99 adult subjects participated in 3 sessions over 3 consecutive weeks. Results showed that overall liking for 2 yogurt samples was higher in the laboratory environment under the informed evaluation condition, whereas no effect of research setting was found under the blind and expected conditions. Although emotional profiles of the products differed depending on the research setting, this was less the case for the sensory profiles. Furthermore, brand information clearly affected the sensory perception of certain attributes but had less influence on overall liking and emotional profiling. These results indicate that both scientists and food companies should consider the effect of the chosen methodology on ecological validity when conducting sensory research with consumers because the laboratory context could lead to a more positive evaluation compared with a home-use test. 相似文献
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