Effect of Packaging Materials and Storage Condition on Keeping Quality of Bleached Lac

Abstract

A study on the effect of different packaging materials and storage conditions was carried out on keeping quality of freshly prepared bleached lac packaged in five different types of packaging materials: Low Density Poly Ethylene (LDPE ), High Density Poly Ethylene (HDPE), Poly Propylene (PP), Metalized Polypropylene film (METPP) and  five layer craft Paper Bag (PG). The samples were stored in both ambient and refrigerated conditions (14-16⁰C) and quality parameters were evaluated at quarterly interval after 3, 6, 9 and 12 month of storage followed by comparison with samples stored in open condition. For storage under ambient condition in room, the flow value (fluidity), life (heat polymerization time) and acid value (AV) of the packaging material were highest for metalized film bag i.e.10mm, 5 min. and 70.69 respectively and impurity content was least (2%) after 3 months of storage due to high amount of moisture (4.12% db) retained in the sample. These parameters were lower in other packaging materials due to lower moisture content (1.38-2.40% db) with the lowest value (1.01% db) in open storage condition. Although there was no difference in flow value and life of samples after six months of storage in different packaging materials, impurity content was lower and acid value was higher in metalized film compared with others. For storage under refrigerated condition, these parameters were higher compared to ambient storage for all packaging material. Flow value, life and acid value of samples in metalized bag were highest; 35mm, 10 min. and 74.36 after 3 months of storage. However, these parameters were lower in others packaging materials due lower moisture content (1.50-2.61% db) with lowest value (1.23% db) in open storage condition. The flow and life of samples packaged in metalized film bag were highest i.e. 25mm and 5 minutes respectively after six months of storage as compared to when packaged in others.  Also, the impurity (insoluble matter) content was lower (0.80%) compared to (1.30-1.41%) for other packaging materials with highest deterioration (3.27%) reported in open storage condition. These parameters were observed for different packaging materials under refrigerated condition up to one year of storage. Least amount of impurity (1.16%) and highest acid value (74.96) were observed in metalized film bag compared to others for up to one year of storage. During this study it was observed that keeping quality of bleached lac samples was better in metalized film bag (82.5µ) compared to other packaging materials for both ambient and refrigerated storage condition.