Abstract
Fish crackers are a traditional Malaysian snack food and are known as Keropok. It has a short shelf life and is easily rancid due to oxidation. This study was conducted to determine the effect of covering package material using paper-sticker on the physicochemical and sensory properties of fish crackers during storage. A storage study of deep-fat-fried keropok was carried out for three months at ambient temperature (27ºC) using Polypropylene (PP) packaging material covered with 0% paper sticker (as control), 40% paper-sticker, and 80% paper-sticker. Oxygen transmission rate (OTR), moisture content, peroxide value (PV), thiobarbituric acid (TBA), and sensory attributes of the fish crackers were analyzed after 0, 1, 2, and 3 months. All parameters increased significantly with time (P<0.05) in all the samples under different percentages of paper-sticker covering the packing material. Polypropylene plastic bags covered with 0% paper sticker (as a control) recorded the highest oxygen transmission rates (OTR). However, covering of PP plastic bag with 80%paper-sticker reduced more than 60% oxygen transmission rate (OTR). After three months of storage time, the PV and TBA values were significantly lower (P<0.05) for samples packaged with PP covered with 80%paper sticker compared to samples packaged with polypropylene (PP) covered with 0% and 40% paper-sticker. Sensory attribute scores had decreased during storage time. The scores of crispiness, overall acceptability and off- flavour were significantly higher (P<0.05) for samples packaged with 80% paper-sticker compared to PP film with 0% paper-sticker after one and two months of storage time. The best percentages of the paper-sticker covering packaging material is PP with 80% paper-sticker. Therefore, using paper-sticker with 80% was able to reduce OTR and showed a delay rancidity by decrease of PV and TBA values.