162
FREEZE—DÈYING
the inuence of different variations of temperature during distribution of the product
on its quality by multiplying the days experienced at each temperature with the daily loss:
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of quality indicated by the curves ; in this example the total is = 1.320.
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200 Time (days)
FIGURE 16. Time — Temperature —— History diagram for frozen cod llets.
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This graph also Shows the accumulated quality loss in another way : the average storage
temperature can be calculated and then the quality loss determined with the help of F1gure 2,
showing quality loss over storage
time for different temperatures.
One can also use this
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quality characteristics curves for converting the various time—temperature values to corres- -
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ponding periods at a standard temperature (eg. —— 18°C) and then…make the addition};
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This graph indicates—that the
e”e0t of short temperature rise on quality loss is relatively
FromthegraphshkeFigure9,showmgthe loss“…of quà1i:ymf a specic
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'ristiéë diagram can be drawn1fthe
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For derent—but constant—acceptedquahtyofthe
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onesmFrgure17,vahdforleansh(hkecod) Acceptmgsomemmrmumquahty—eg
thekeepgquahtycharactenstlcscurveaybe1ndlca—tedbyu51ng‘theiîtefperàtürôÿ ;
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products