Ultrasonic freezing

Emerging Food Technologies Presentation Series - 2016

University Of Sri Jayewardabepura

Ultrasonic technologyIn

Food Science & Technology

M.D.S.Ruwanthika



Sanduni Ruwanthika

Devi Balika VidyalayaColombo 08

I want to be a good Sri Lankan with good carrier related Food Science & Technology

I always believe thatMoney is not everything but it is something, however my family is my everything.



Over view

Introduction with background Fundamental theories Applications Advantages & Disadvantages Examples References



Introduction with Background

ThermalNon thermal High Hydrostatic Pressure Pulsed electric fields Ultraviolet Ultrasound Irradiation Chemicals Cold Plasma

• Microwave• Ohmic Heating• Radiofrequency• Induction Heating

Emerging food

Technology



Introduction Contd…

Ultrasound for Food??? Emerging technology Minimize processing Maximize the quality & safety of foods Improvement in

Mass transfer Food preservation Assistance of thermal treatments Manipulation of texture Food analysis



Fundamental Theory

o Simply It means a sound waves of frequencies which can not be identified by the human ear (above 20kHz).

o Called as ultrasound.o Form of energy. o Can propagate in gases, liquids & solids.o resulting in a series of compression and

rarefaction.



Theory contd….During the process• Create longitudinal waves• Results compressions & expansions• Pressure change cause to form cavitation & air

bubbles• Larger surface area increases the diffusion of gas

into bubble• Expand the bubble, Condensation occur



Theory contd….

• Condensed molecules collide each other • Create high shock waves

• Results high temperature & pressure

• cavitation creates shear forces that break cell walls mechanically and improve material transfer.



UltrasoundLaw Energy Ultrasound

High Energy Ultrasound

Theory contd….



Ultrasound in Food Science & Technology

Inactivation of microorganisms & enzymes

Modifications• Anti oxidant modification• Bioactive modification• Color modification• Polysaccharide modification



Increasing the efficiency of Unit OperationsUltrasound assisted

• Freezing• Extraction• Filtration• Osmatic dehydration• Drying• Emulsification in Lipid Containing Foods

Ultrasound in Food Science & Tech. contd..



Increasing the efficiency of Unit Operations Contd…

Ultrasound assisted• Cutting in Lipid Containing

Foods• Homogenization in Lipid

Containing Foods• Fermentation• Defoaming



FreezingInfluence the initiation of crystal nucleation, control the rate of crystal growth, ensure the formation of small and even-sized crystals, and prevent fouling of surfaces by the newly formed crystals.

Ultrasonic Freezing Technology can be applied to foods where it can be used to control the size and rate of development of ice crystals in frozen foods Ex:- meats, fruits and vegetables, Ice cream



Extractionorganic compounds from plants or seeds has classically been based upon the judicious combination of solvent, heat and/or agitation.

Due to ultrasonic cavitation creates shear forces that breaking cell walls mechanically and improving the material transfer.



Applications

Plant Foods

Fruit Juices Orange Juice Tomato Juice Blackberry Juices Apple juices

Fruits & vegetables Quality control of fresh vegetables

and fruits Detecting of defective potatoes



Dairy Foods

Disruption of fat globules of milkApplications Contd…



Oily Foods

Applications Contd…

Phenolic compounds in nuts

Lipids of nuts

Microbiological quality of nuts



Applications Contd…

• To make long term stabilized emulsions Ex:- Mayonnaise• Reduce the production timeEx:- yoghurt• Inhibition of enzymesEx:- Pure pepsin• More novel applications



Advantages

With less additives With high nutritional value High quality Less thermal damage Good sensory properties Safe products Rapid, non-destructive,

precise, fully automated



Disadvantages

Off-flavors Structural modifications free radicals Sometimes metallic taste Need highly technological instruments Very limited range of foods as it is an

expensive technology



Ultrasonic can be a specialized and versatile technology with numerous applications in food processing.

Ultrasonic processing is still in its infancyand requires a great deal of future research in order to develop the technology on an industrial scale.

Conclusion



References

http://www.slideshare.net/mjrulzz/quality-control-techniques-for-food-safety/19-Food_Irradiation

www.scirp.org/journal/PaperDownload.aspx?paperID=35845




http://www.scirp.org/journal/PaperDownload.aspx?paperID=35845

http://www.scirp.org/journal/PaperDownload.aspx?paperID=35845



Thank You

Education

Ultrasonic freezing