Effects of micro-perforated film on the quality and shelf life improvements of pork loins during chilled storage.

The effects of micro-perforated film (MPF) packaging method on the quality and shelf life of pork loin during chilled storage were investigated, compared with non-packaging (control) and non-perforated film (PPF) packaging. Loins were removed from five hogs after slaughter and chilling, and each loin was portioned into four parts. These samples (40 sections) were allocated to each of five intervals (0, 1, 4, 7 and 14 days) to minimize variation among treatments and stored for 14 days under 55±10% relative humidity and 0±1 °C. Total aerobic counts of control sample were significantly lower than those from MPF or PPF loins after 14 days of storage. At 14 days, the counts of Pseudomonas and Enterobacteriaceae in the samples from MPF were significantly lower than those from PPF. At 7 days, 'L' value for the control and 'a' value for PPF were significantly lower, and ΔE values for the control were significantly higher than other samples. During storage time, percentage weight loss was the most in the control samples with MPF following and PPF the least. Accordingly, water contents decreased highest in the control samples followed by those from MPF and PPF. TBA values increased with storage time, however no significant differences were observed among treatments. Sensory evaluation analyses showed that MPF samples were generally better evaluated in all parameters over the storage time. Therefore, it has been concluded that MPF could be used as an effective packaging technology since it extends the shelf life of fresh meat by controlling the microbial growth and evaporation at a moderate level.