The Effect of Packaging Materials and Storage Temperatures on Shelf Stability of RDB Palm Olein

Abstract

The oxidative stability is a considerable factor which affect the quality and shelf stability of edible oil. There had been reported issues of quality degradation of RBD palm olein before the expiry date due to this. The packaging material and storage temperature play an important role in shelf stability thus the objective of the current study was to investigate this effect on shelf stability of RBD palm olein. Plain PET bottles, shrink wrapped PET bottles, PET pouches (PET+ PE + Nylon) and glass bottles were tested as packaging materials in this study. Physicochemical parameters were evaluated to measure the shelf stability for 60 days at 37 ◦C, 27 ◦C and 19 ◦C. The consumer preference, awareness and requirements of alternative packaging material were assessed via a Google questionnaire. The results showed that Free Fatty Acid (FFA) value increased with higher storage temperatures and the sample in glass bottle showed the lowest FFA values (0.083±0.002% at 37 ◦C). Secondary oxidation occurred in most of samples at higher temperatures. The oxidation was also lower in glass bottle than the others while initial peroxide value showed as 1.43±0.02 meq/kg. Initial iodine value showed as 60.963±0.542 which did not significantly vary among the packaging materials and storage temperatures. Color was affected of the samples in pouch at all temperatures while it was affected at the highest temperature tested for other packaging materials. The initial cloud point indicator was 8 ◦C which showed no considerable change with the time. The shelf life reduced at 37 ◦C temperature than 19 ◦C in all samples and the highest shelf life is rejected as 1.2 years in glass bottles, in rapid testing for 2 months. It was revealed that the glass bottle showed the highest shelf stability according to the measured parameters while it was the most preferred (60%) packaging material based on the survey results. The manufacturers indicated the concerns about the cost, size and shape in selecting a packaging material. Nevertheless, the manufacturer expressed the willingness of modifying the existing packaging to enhance the shelf stability.