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Ultra-High Pressure Pasteurization of Fresh Cut Pineapple
Giovanna Alemán1, Daniel F Farkas1, J Antonio Torres1
1Food Process Engineering Group, Department of Food Science & Technology, Oregon State University, Corvallis, Oregon 97331-6602.
Journal of Food Protection
|May 25, 2019
Summary
Ultra-high pressure processing effectively extends the shelf-life of fresh-cut pineapple. High pressure (340 MPa) significantly reduced microbial loads, preserving pineapple quality for longer storage.
Area of Science:
- Food Science
- Microbiology
- Horticultural Science
Background:
- Fresh-cut pineapple is perishable, limiting its shelf-life.
- Microbial contamination (bacteria, yeast, mold) is a primary cause of spoilage.
- Extending shelf-life requires effective microbial reduction strategies.
Purpose of the Study:
- To evaluate the efficacy of ultra-high pressure processing (UHPP) in extending the shelf-life of fresh-cut pineapple.
- To determine optimal pressure, temperature, and time combinations for microbial inactivation.
- To assess the impact of UHPP on bacterial and yeast/mold populations.
Main Methods:
- Fresh-cut pineapple chunks were subjected to UHPP at pressures of 200, 270, and 340 MPa.
- Treatments were applied at various temperatures (4°C, 21°C, 38°C) and durations (5-60 min).
- Microbial analysis involved quantifying surviving bacteria and total yeast/mold counts using plate count agar (PCA) and acidified potato dextrose agar (PDA).
Main Results:
- The highest pressure (340 MPa) for 15 minutes achieved significant decimal reductions in bacterial counts (>2.5 to 3.1 log CFU/g) across tested temperatures.
- At 270 MPa and 15 minutes, substantial reductions were observed only at 38°C.
- Lower pressure (200 MPa) resulted in approximately one decimal reduction in bacterial counts, with yeast and mold counts showing similar trends.
Conclusions:
- UHPP is a promising technology for reducing microbial load in fresh-cut pineapple.
- Higher pressures and specific temperature/time combinations are more effective for microbial inactivation.
- UHPP treatment can significantly enhance the shelf-life of minimally processed pineapple products.
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