Detection of nitrite in cured meat
with QUANTOFIX® Nitrite |
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Background |
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In Europe many meat products like ham and smoked pork chop are cured. Curing is a process to preserve meat and sausages by addition of common salt. The meat develops a typical curing taste and becomes red in color. This process is important to avoid a grey coloration and a growth of microorganisms.
But by the reaction of nitrite with amino acids, carcinogenic nitrosamines might be formed.
Therefore it is important to minimize the concentration of nitrite in meat. A constant control of the concentration of nitrite in meat is necessary to avoid risks.
The German directive "zweite Verordnung zur Änderung der Zusatzstoff-Zulassungsverordnung und anderer lebensmittelrechtlicher Verordnungen" (concerns approval of additives in food) defines limit values for the permitted concentration of nitrite in food. For meat products a maximum quantity of 150 mg/kg is prescribed. Sterilized meat products are not allowed to exceed the maximum quantity of 100 mg/kg.
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Test procedure |
Sample preparation:
Take 5 g meat of the sample and give it into a mortar. Mince the meat and add 8 ml sodium acetate solution1) (13.6 g sodium acetate in 100 ml distilled water). Mix for 1 minute. Afterwards filter through a soft filter and press slightly to get some filtrate. Folded filter paper like MN 617 we1) is most suitable for the filtration.
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Give 5 g meat into a mortar and mince.
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Add 8 ml 1 N sodium acetate solution1) and mix for 1 minute.
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Filter through a soft filter. |
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Testing:
Dip the test strip into the filtrate for a few seconds. Remove the test strip and wait for 30 seconds. Compare the test field with the color scale on the tube. A red-violet coloration indicates the presence of nitrite ions.
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Dip the test strip into the filtrate. |
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Compare the test field with the color scale. |
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A red-violet coloration detects nitrite ions. |
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Product data and ordering information: QUANTOFIX® Nitrite |
Type |
Semiquantitative test strip |
Presentation |
Tube of 100 test strips |
Color reaction |
white to red-violet
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Limit of sensitivity |
0-1-5-10-20-40-80 mg/l NO2-
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Reference |
91311 |