Presentation on high pressure processing.pptx

hpp in food

1. EMERGING NON THERMAL METHODS OF FOOD PRESERVATION

2. High pressure processing ANSU SARA MATHEWS IV th YEAR UNDER GRADUATE 1101010005

3. Contents Definition Different names of HPP Description Principle Operations of HPP Safety of food References

4. Definition A method in which food is subjected towards elevated pressure, with or without addition of heat

5. Introduction HPP is also known as high hydrostatic pressure processing and ultra high pressure processing Pressures between 50-1000MPa- subjects to liquid and solid foods Used-microbial inactivation, extends microbiological shelf life, retains food quality, maintains natural freshness, color and flavor Eliminates thermal degradation This method-beneficial for heat sensitive products

6. Description Food product – placed in pressure vessel-contains liq.(pressure transmitting medium) Pressure transmitting medium(castor oil, water, sodium benzoate etc)- prevents from corrosion(inside vessel) Factors for selecting medium process tempt range Viscosity of the fluid under pressure

7. Operations of HPP Batch or continuous -depends on the type of product Solid foods- batch Liquids, slurries, pumpable – semi continuous

8. Batch process Product placed in high pressure chamber-filled with medium and pressurized(pumping pressure into or reducing the volume of pressure chamber Solid products used

9. For eg : water is used as pressure transmitting medium- first factor taken into account is compressibility Water is compressed upto 15% of vol. at pressure above 600 MPa Once the desired pressure is reached, piston is stopped, vessel closed and maintained without further energy input After required holding time is elapsed , system is depressurized, vessel opened – pdt unloaded.

10. Continuous process Pumpable products are used. Use a pressure vessel with a free piston to compress the liquid food. A low pressure food pump is used to fill the pressure vessel, and as the vessel is filled the free piston is displaced Once filled, the inlet port is closed and high pressure water is passed behind the free piston to compress the liquid foods

11. After appropriate holding time, releasing the pressure on the high pressure process water decompresses the system. The treated liquid is discharged from the pressure vessel to a sterile holding tank through a discharge port. A low pressure water pump is used to move the free piston towards the discharge port- then liquid can be transferred into sterile container tanks

12. Process principles Le Chatelier’s - when a system at equilibrium is distributed the system responds in a way that tends to minimize the disturbance. Isostatic rule- the pressure is instantaneously and uniformly transmitted throughout a sample under pressure whether the sample is in direct contact with the pressure medium or hermetically sealed in a flexible package that transmits pressure

13. Use of high pressure to improve food safety and stability To eradicate pathogenic microorganisms-food safety Inactivation of spoilage microorganisms-to improve the shelf life HP treatment causes sub lethal injury to microbes It retains the nutritional and sensory value of the pdt .

14. Disadvantages of using high pressure It can cause greater levels of protein denaturation and other changes in food quality Capital cost is high

15. Advantages Increased safety, shelf life, nutritional quality and sensory quality HPP also improves the gelation properties of meat, improves the coagulating properties of milk

16. References Emerging technologies of food processing. pdf - high pressure processing of food High pressure processing fact sheet for food processors.

17. THANK YOU