Comparing the function of perforated and non-perforated film in MAP: impact on the quality of broccoli
Randolph M. Beaudry and Fernando Vallejo
Program and Abstract. 9th Controlled Atmosphere Research Conference (CA2005). Michigan State University, East Lansing, Michigan, USA. July 5-10, 2005. page3
2005
บทคัดย่อ
Comparing the function of perforated and non-perforated film in MAP: impact on the quality of broccoli
The atmospheres obtained in perforated and non-perforated packages differ. Based on gas diffusion characteristics, CO2 levels are elevated in the perforated packages relative to non-perforated packages for a given level of O2. A higher level of CO2 may be expected to improve quality retention by virtue of the inhibitory effect of CO2 on ethylene action and chlorophyll degradation. Perforated (EPL Perforate films, Oswego, IL) and non-perforated packages composed of low density polyethylene (LDPE) film were used to create modified atmospheres for the storage of broccoli. Haft of the broccoli was treated for 24 h at 10°C with 1 ppm 1-MCP. The patterns of O2 and CO2 differed markedly between perforated and on-perforated packages. When the package O2 was regressed against package CO2, distinctly different trends were apparent for the two package types. The curve fitting the data for non-perforated packages was linear with a negative slope such that for every 4 kPa decrease in O2, there was 1 kPa increase in CO2, the curve fitting the data for perforated packages was also linear and negative, but steeper, such that for every 4kPa decrease in O2, there was a 4 kPa increase in CO2. At O2 partial pressures greater than 3 kPa, broccoli quality was significantly better in the perforated packages than in the non-perforated packages. 1-MCP improved the color retention of broccoli so that the impact of perforations was more obvious for florets not previously treated with 1-MCP.