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High-Pressure Pasteurization of Oat Okara.
Amanda Helstad1, Ali Marefati1, Cecilia Ahlström1
1Department of Food Technology Engineering and Nutrition, Lund University, Naturvetarvägen 12, 223 62 Lund, Sweden.
Foods (Basel, Switzerland)
|November 25, 2023
Summary
High-pressure pasteurization at 600 MPa significantly reduced microbes in oat okara, extending its shelf life to 2-4 weeks. Further research is needed to ensure its safety for food applications.
Area of Science:
- Food Science
- Microbiology
- Food Engineering
Background:
- Plant-based beverage residues, like oat okara, present a significant food waste challenge due to short microbiological shelf life.
- Current uses for oat okara include energy conversion or animal feed, limiting its potential as a food ingredient.
Purpose of the Study:
- To investigate the impact of high-pressure pasteurization on the microbiological shelf life of oat okara.
- To analyze the effects of high-pressure treatment on the thermal properties, viscosity, and water/oil holding capacities of oat okara.
Main Methods:
- Oat okara was subjected to high-pressure pasteurization at 200 MPa, 400 MPa, and 600 MPa.
- A 4-week microbiological storage study was conducted at 4 °C.
- Analysis included total aerobic count, yeast and mold, lactic acid bacteria, thermal properties, viscosity, and water/oil holding capacities.
Main Results:
- 600 MPa treatment significantly reduced total aerobic counts, yeast, and mold (p < 0.05) after four weeks.
- Lactic acid bacteria content was reduced to the detection limit (2.3 log CFU/g) with 600 MPa treatment.
- 200 MPa and 400 MPa treatments unexpectedly increased microbial counts after two weeks (p < 0.05).
- Higher pressures (400-600 MPa) increased protein denaturation of avenalin (12S globulin).
- Water holding capacity was unaffected except for a reduction at 200 MPa; oil holding capacity remained constant.
Conclusions:
- High-pressure pasteurization at 600 MPa can extend the shelf life of oat okara to 2-4 weeks by reducing microbial load.
- Further research is necessary to identify specific microorganisms and ensure the microbiological safety of oat okara for food applications.
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