Why does the packaging bag of pickled vegetables have a peculiar smell during use?

Why does the packaging bag of pickled vegetables have a peculiar smell during use? Quality problem: When opening the packaging bag or wrapping film of pickled vegetables, there is a pungent odor, and even the packaged pickled vegetables have a similar odor
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Reason analysis: - Improper control of packaging materials and printing process - resulting in insufficient volatilization of organic solvents (alcohols, ketones, esters, benzene and other solvents) for dissolving printing ink, especially in the acidic environment of pickles , the residual solvent is more likely to migrate into the food, affecting the health of consumers; • Improper control of the compounding process - when the packaging compound film used is compounded with adhesive, the organic solvent for dissolving the adhesive is not fully volatilized; • Poor quality of raw materials - the resin used for the production of packaging materials or the content of small molecules with odors added to it is high; • Poor quality of adhesives - the adhesives used in the compounding process are at high temperature Harmful substances such as toluene diamine are produced
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Testing suggestions: ——Pay attention to the monitoring of hygienic performance indicators such as solvent residues, evaporation residues, toluenediamine content, and potassium permanganate consumption in packaging
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——Choose suitable inks and adhesives (such as solvent-free inks), and adjust the process parameters of volatilization and drying during printing and compounding
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Typical quality cases: ——Test sample: Spicy Flammulina velutipes packaging plastic composite film (customers reported that they smelled a strong paint smell when opening the packaging film of this product, and were worried about affecting the quality of Flammulina velutipes)
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- Targeted testing items: solvent residues
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——Test results: The total amount of residual solvent in the plastic composite film is 24.
5 mg/m2, of which the content of ester solvent is 19.
95 mg/m2, and the content of benzene solvent is 2.
95 mg/m2
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According to the relevant regulations in GB/T 10004-2008 "Plastic Composite Film, Bag Dry Compounding, Extrusion Compounding for Packaging", the total amount of solvent residues should not be higher than 5.
0 mg/m2, and benzene solvents should not be detected, so The solvent residue and benzene solvent content of the plastic composite film exceeds the standard range, which is an important reason for the peculiar smell of the packaging.
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