Development of controlled ethanol vapor release sachet for shelf life extension of fresh-cut Baby Cos lettuce

Abstract

Baby Cos lettuce is a salad that was popularly consumed due to its sweet taste and crispy texture. However, ready-to-eat Baby Cos lettuce has a short shelf life, typically only lasting 3 days at 4±1˚C. Baby Cos lettuce is easily spoiled because there is a large amount of water content within the cells, and the wounds from trimming are easy for bacteria to grow. If it was a disease-causing bacterium, it could be dangerous to consumers. Therefore, the objective of this research were to develop an ethanol vapor release sachet to be applied with packaging of pre-trimmed and ready-to-eat Baby Cos lettuce, as well as to study the effects of using the ethanol vapor release sachet on the shelf life of ready-to-eat Baby Cos lettuce. The ethanol sachet, size 3×3 cm, consisted of 1 gram of silica gel saturated with ethanol liquid. Three types of laminated film were used with the ethanol sachet, namely low density polyethylene (LDPE), fresh&fresh and perforated aluminium/PE sealed with aluminium/PE on the other side. The study demonstrated that using aluminum/PE vapor release envelopes with small holes, combined with ethanol evaporation sachet, effectively slows down the growth of microorganisms in fresh cut baby cos lettuce. This method was significantly more effective compared to the control samples that did not use ethanol released sachet, as indicated by a statistical significance (p≤0.05). In terms of sensory quality, the study found that consumers preferred the salad packaged with these ethanol vapor release envelopes. These vegetables were rated higher for freshness, color, aroma, and less browning of the cut areas, This suggests that the ethanol vapor release sachet are effective not only in extending the shelf life by preventing microbial growth but also in maintaining the sensory quality of the vegetables. Using the ethanol vapor release sachet,