Find the best characterization technique for chocolate or ingredient of it and answer following question:
1-justify why you have chosen this particular technique for this particular product(15%)
2-explain the basis of your chosen technique and its advantages and disadvantages(25%)
3-explain what other techniques might be used or have previously been used to characterize your product (25%)
4-how does the micro structure of your product determine its performance(25%) and 10% for full references and use of English ——————————————————————————— i have attached a paper i found about it , i hope it will help but i am not sure, above mentioned text is the only instruction i have ——————————————————————————— i am a master student in chemical engineering department in UK and this essay is for a course named “measurement techniques”. ——————————————————————————— it is very important for my lecturer to put lots of information in short sentences or a paragraph ——————————————————————————— thank you in advance
Why the Technique
Quality inspection gains more and more importance in food industry and in particular in chocolate production. Metal detectors are commonly used to locate metallic contamination, but the spatial resolution is not very high. In the praline industry for example, where there are 50 pieces next to each other in row, high rejection rates are very common. If the metal detector locates any contamination, the whole row of pralines is discarded. And as a precaution the row in front and behind the suspicious row is sorted out, too. It is very likely that only one of the 150 discarded pralines is actually contaminated, while the rest is not. The goal of lowering such high rejection rates could be accomplished with the help of a higher spatial resolution. There is a large interest from the chocolate industry to detect non-metallic contaminations like stones or glass particles. Stones present in chocolate come from natural products like nuts and glass contaminations can originate from everyday-life objects such as light bulbs. Certain chocolate factories maintain a glass register where all glass materials which are close to the production line are mentioned. This register has to be checked every week for any missing glass equipment. The apparent concern about glass pieces suggests that a detector to find glass contaminations in chocolate bars is highly desirable. Furthermore, the chocolate industry develops an increasing number of new products especially in the field of truffle production. THz waves in collaboration with other techniques may be used to ascertain that the different parts of the truffle are included in the appropriate proportions. However, currently used THz imaging systems must become much faster to be used in industrial production lines. Therefore a new approach with less scanning time is required, to check a chocolate bar, for example.
Basis, Advantages and Disadvantages
Metal, stone, or glass contaminations can be detected in chocolate bars with a spatial resolution
of less than 1 mm (cf. Fig. 5). Both pictures below show diagrams for the transmitted
intensity between 0.4 and 0.5 THz on a logarithmic scale. The size of both pieces is roughly
5 cm by 6 cm. The transmitted intensity for glass and stone contaminations is lower due to
higher absorption and scattering losses. Metal, on the other hand, reflects all THz radiation and decreases therefore the transmitted intensity. Even if the chocolate is measured in its
own original plastic package the contamination is clearly visible. Plastic foil is nearly
transparent to THz radiation. Aluminium foil on the other hand reflects all THz radiation
and hence chocolate bars wrapped in aluminium foil cannot be investigated with THz radiation.
If there are any contaminations inside the chocolate bar, like a stone or a glass splinter on the scale of millimeters, the THz pulses have a different shape (cf. Fig. 7 a, dotted and dashed-dotted line). Basically, two smaller pulses appear close to each other (cf. Fig. 6 in the middle of the waterfall), which are generated by two portions of the main THz pulse. One part of the pulse travels aside the contamination, the second part travels through the contamination and has experienced a time delay due to the higher refractive index of the glass splinter or the small stone. Since the first THz pulse is smaller than the main one, a dip occurs in the sum of two line scans (circled area of the curves in Fig. 7 d) indicating the contamination. If contaminations inside grooves of the chocolate bar should be detected, the time delay for the line scan must be set accordingly. Comparable measurements on chocolate bars show (results are not given here) that scanning speeds of 0.55 m/s are feasible.
Other Techniques
-Compensated DSC
-micrometrics notes
Micro Structure of Product Determine Performance
References
Credit:ivythesis.typepad.com
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