VOLATILE COMPOUNDS EXTRACTED FROM POLYPROPYLENE SHEETS BY HOT-WATER -INFLUENCE OF THE TEMPERATURE OF SHEETS INJECTION

The influence of the formulation of polypropylene (PP) on the organole ptic properties of the foodstuff in contact is of great importance for the quality of the product. A study was made on PP pellets degraded a nd not degraded and pointed out the presence and olfactive importance of volatile components extracted from PP pellets by hot water. Plastic packaging materials correspond to a further step of manufacturing: th e injection step, and this is often conducted at high temperature. PP (not degraded) and PP-CR (degraded) were transformed into sheets at se veral temperatures; Lickens-Nickerson extracts were made and allowed t he quantification of volatile compounds already identified. A statisti cal analysis showed that temperature was a very significant parameter. An increasing injection temperature (275 or 300-degrees-C) creates in creasing quantities of volatiles. This was well correlated with the se nsory analysis made on the organic extracts of the sheets and also dir ectly on molded cups. (C) 1993 John Wiley & Sons, Inc.