Microbial Assessment and Sensory Acceptance of Extended Shelf Life Commercial Inflight Nasi Lemak Stored at Chill Temperature Using Acidity Regulator

In this study, the effects of acidity regulators on the shelf life, quality, and organoleptic characteristics of inflight nasi lemak were investigated. High nutritional, moisture and fat content in rice have led to some limitations to the shelf life of ready-to-eat meals when kept at a chill temperature during commercial retail. The short shelf life of fresh Nasi Lemak (non-frozen ready to eat meal) is around five to seven days. Complaints on Nasi Lemak have been received about the poor quality of broken rice in the frozen Nasi Lemak. Hence, two types of permitted acidity regulators known as Soluex 220301 and Soluex 220302 were added to the chilled Nasi Lemak at 0.5% and 1% concentrations respectively. It is hypothesized that the use of the acidity regulators give a substantial effect on the growth of microbes during the chill storage of Nasi Lemak for 24 days as it retard microbial growth in the meals. Determination of the shelf life was conducted by microbial counts of Total Plate Count (TPC) and the enumeration of Escherichia coli, Staphylococcus aureus and Salmonella. E.coli was seen absent throughout the study in all samples whereas lesser bacterial growth was seen in Nasi Lemak added with Soluex 22302 with a concentration of 1% during the 24 days in chill storage. Organoleptic attributes were conducted by nine trained panelists on five attributes: color, texture, odor, taste, and overall preference by using a ranking method. Data collected from Day 1 until Day 24 were analyzed using the Least Significant Difference test (LSD) showed that Nasi Lemak added with Soluex 22302 with a concentration of 1% received a high rating by the panelist even until the last day of the experiment. The results of the study clearly show that bacteria of TPC, Salmonella, E.Coli and Staphylococcus aureus were significantly affected by the concentration of acidity regulator Soluex 22302 1%.