The document discusses various thermal processing techniques used in food processing, including ultrasound, ohmic heating, and their applications. It begins by explaining that food processing transforms raw agriculture into shelf-stable, edible products through various unit operations. It then discusses techniques like drying, frying, smoking and pickling. The document goes on to explain concepts like ultrasound frequency, generation of ultrasound using transducers, and applications of ultrasound in areas like microbial inactivation, enzyme inactivation, and food processing operations. It also provides details on ohmic heating, its principles and generation of heat through electrical resistance.
The document discusses the use of oscillating magnetic fields (OMF) to inactivate microorganisms for food preservation. OMF involves applying magnetic fields of intensities between 5-50 tesla and frequencies of 5-500 kHz. This process reduces microbial populations by at least 2 log cycles. The mechanisms of OMF inactivation involve loosening ion bonds in cell membranes and disrupting calcium/magnesium ions. While OMF shows potential for food preservation, further research is still needed to fully understand its effects on microbial destruction kinetics and food quality.
Pulsed electric field (PEF) technology uses short, high voltage electric pulses to induce pores in cell membranes, causing microbial inactivation and cell disintegration without significantly heating the food. This allows for longer shelf life and fresh quality retention compared to thermal pasteurization. PEF works by exceeding the critical transmembrane potential of cells, typically around 10 kV/cm for E. coli. It is effective against vegetative microbes and can reduce microbial loads by 4-6 logs but has limited effectiveness against spores, viruses or enzymes. PEF is suitable for liquid, semi-liquid and some solid foods but requires expensive equipment and refrigeration to extend shelf life.
This document provides an overview of ultrasound technology and its various applications in food processing. It discusses ultrasound frequency and power, the mechanisms of action including acoustic cavitation and bubble formation, different methods of ultrasound generation using transducers, and various applications in meat, dairy, fruit and vegetable processing, emulsification, oil processing, and honey. Key areas that ultrasound is used include tenderizing meat, removing fat from dairy, maintaining quality of fresh produce, forming emulsions, and increasing reaction rates for processes like biodiesel production.
Ultrasonic processing is a non-thermal food preservation technique that uses high-frequency sound waves. It can inactivate microorganisms and enzymes through cavitation effects. When combined with heat or pressure, ultrasonication is more effective at preservation. It has advantages over thermal processing like minimizing flavor and nutrient loss. Further research is needed to optimize ultrasonication for commercial-scale food preservation applications.
Pulsed electric field (PEF) processing is an emerging non-thermal food preservation technology. PEF technology is established on the utilization of electric fields to remove food-borne pathogens and to subjugate the spoilage microorganisms in foods. This technology is notably acknowledged for its capability to amplify the mean life of food products without the utilization of heat also preserving the quality aspects such as sensory and nutritional attributes, together with enabling the safety of food products
This document provides an overview of high pressure processing (HPP) of foods. HPP uses high pressure, around 400-600 MPa, to inactivate pathogens and microorganisms while minimally affecting the food's qualities. HPP retains food quality by preserving nutrients, texture, taste and appearance. It has applications for foods like meats, seafood, juices, sauces, dairy products and more. The advantages of HPP are that it achieves uniform microbial reduction without heat, maintains sensory qualities and is more environmentally friendly than thermal processing. The document discusses the basic principles, history, equipment, generation of pressure, applications and advantages and disadvantages of HPP.
The document discusses the use of oscillating magnetic fields (OMF) to inactivate microorganisms for food preservation. OMF involves applying magnetic fields of intensities between 5-50 tesla and frequencies of 5-500 kHz. This process reduces microbial populations by at least 2 log cycles. The mechanisms of OMF inactivation involve loosening ion bonds in cell membranes and disrupting calcium/magnesium ions. While OMF shows potential for food preservation, further research is still needed to fully understand its effects on microbial destruction kinetics and food quality.
Pulsed electric field (PEF) technology uses short, high voltage electric pulses to induce pores in cell membranes, causing microbial inactivation and cell disintegration without significantly heating the food. This allows for longer shelf life and fresh quality retention compared to thermal pasteurization. PEF works by exceeding the critical transmembrane potential of cells, typically around 10 kV/cm for E. coli. It is effective against vegetative microbes and can reduce microbial loads by 4-6 logs but has limited effectiveness against spores, viruses or enzymes. PEF is suitable for liquid, semi-liquid and some solid foods but requires expensive equipment and refrigeration to extend shelf life.
This document provides an overview of ultrasound technology and its various applications in food processing. It discusses ultrasound frequency and power, the mechanisms of action including acoustic cavitation and bubble formation, different methods of ultrasound generation using transducers, and various applications in meat, dairy, fruit and vegetable processing, emulsification, oil processing, and honey. Key areas that ultrasound is used include tenderizing meat, removing fat from dairy, maintaining quality of fresh produce, forming emulsions, and increasing reaction rates for processes like biodiesel production.
Ultrasonic processing is a non-thermal food preservation technique that uses high-frequency sound waves. It can inactivate microorganisms and enzymes through cavitation effects. When combined with heat or pressure, ultrasonication is more effective at preservation. It has advantages over thermal processing like minimizing flavor and nutrient loss. Further research is needed to optimize ultrasonication for commercial-scale food preservation applications.
Pulsed electric field (PEF) processing is an emerging non-thermal food preservation technology. PEF technology is established on the utilization of electric fields to remove food-borne pathogens and to subjugate the spoilage microorganisms in foods. This technology is notably acknowledged for its capability to amplify the mean life of food products without the utilization of heat also preserving the quality aspects such as sensory and nutritional attributes, together with enabling the safety of food products
This document provides an overview of high pressure processing (HPP) of foods. HPP uses high pressure, around 400-600 MPa, to inactivate pathogens and microorganisms while minimally affecting the food's qualities. HPP retains food quality by preserving nutrients, texture, taste and appearance. It has applications for foods like meats, seafood, juices, sauces, dairy products and more. The advantages of HPP are that it achieves uniform microbial reduction without heat, maintains sensory qualities and is more environmentally friendly than thermal processing. The document discusses the basic principles, history, equipment, generation of pressure, applications and advantages and disadvantages of HPP.
Ultrasonication processing of fruits and vegetables Gundewadi
1) Sonication is an alternative non-thermal technology to traditional heat processing of fruit juices that provides benefits such as less processing time, higher nutrient retention, and being more energy efficient.
2) Studies have shown that sonication of fruit juices for durations of 30-60 minutes can increase levels of antioxidants like polyphenols and carotenoids while reducing microbial loads.
3) The mechanism of action involves cavitation bubbles forming during sonication that cause cell membrane disruption in microorganisms leading to inactivation without heat.
Microwaves are electromagnetic waves with wavelengths between 1 mm and 1 m that are used for heating. Microwave ovens generate microwaves at a frequency of 2.45 GHz to heat food through rotation and ionic conduction, causing more efficient heating than conventional methods. The key components of a microwave oven are the magnetron which generates microwaves, the waveguide which directs the waves, and the cooking cavity where food is placed. Microwaves are also used for industrial applications like pasteurization, sterilization, drying and heating materials.
Pulsed Electric Field Processing of FoodStella Mariem
The document discusses various process factors that affect microbial inactivation using pulsed electric fields, including electric field intensity, temperature, pressure, and time of exposure. It explains that increasing any of these factors leads to greater inactivation. It also notes different pulse wave shapes that can be used, and describes how the high voltage electric field pulses cause electroporation, making cell membranes permeable and leading to cell death.
This document discusses pulsed electric field (PEF) processing as a non-thermal food preservation technique. PEF uses short, high-voltage electric pulses to induce pores in microbial cell membranes, leading to cell disintegration and microbial inactivation while minimizing negative impacts on sensory and nutritional properties. The document outlines various PEF applications, factors that influence microbial inactivation, commercially available PEF systems, ongoing research needs, and the potential future of PEF processing.
This document discusses several applications of pulsed electric fields (PEF) in food processing, including juice processing, extraction of plant oils and sugars, meat and fish treatment, and microbial decontamination. PEF works by permeabilizing cell membranes through electropermeabilization, allowing for increased mass transfer and extraction of intracellular components. Its applications provide potential to enhance conventional techniques and increase yields while reducing processing times and temperatures.
Radio frequency processing and Microwave heating in food processing prakashsp13
radio frequency and microwave heating ; these slides are explain about its principle and working mechanism ,application in food processing and its advantages .
1) Ultrasonication uses sound waves above the range of human hearing to process foods. It can be used for non-destructive analysis, emulsification, cleaning, and promoting chemical reactions.
2) Piezoelectric transducers are commonly used to generate ultrasound from electrical signals. Cavitation occurs when ultrasound induces the formation and collapse of bubbles in liquids, generating high pressures and temperatures.
3) Ultrasonication is used alone or combined with heat, pressure, or both for pasteurization and sterilization of foods. It inactivates enzymes and microorganisms more quickly than heat alone. Common applications include dairy, fruit and vegetable processing, and meat tenderization.
High pressure processing (HPP) is a non-thermal food preservation technique that uses high water pressure to kill microorganisms and inactivate enzymes in food. This preserves foods without degrading quality attributes like taste, texture and nutrition. HPP was first researched in the 1890s and commercialized in Japan in the 1990s. It is now widely used for products like meat, fish, cheese, juices and ready meals. HPP systems apply pressures of 200-800 MPa for short periods to inactivate pathogens while maintaining food quality. This processing method is gaining popularity with consumers as a safe, natural alternative to thermal pasteurization and canning.
A non thermal processing, which primarily used for homogenisation of fat particles in liquid foods. Now emerged as a promising techniques having applications in food processing. This document will deliver the basics and applications of ultrasound in food
Non thermal processing of food- Pulsed electric field and visible lightT. Tamilselvan
This document provides information on pulsed electric field (PEF) and pulsed visible light processing of foods. PEF uses short electric pulses to preserve foods through electroporation of microbial cell membranes, while minimizing heat production. PEF has been shown to effectively inactivate various microbes in foods like milk, eggs and juices. Pulsed visible light also uses intense, brief pulses of light to inactivate microbes in foods photochemically and through localized heating. Both techniques are non-thermal alternatives to traditional food processing that reduce degradation of nutritional and sensory qualities compared to heat treatments.
Cold plasma is a novel non-thermal food processing technology that uses ionized gas at low temperatures. It generates reactive species like oxygen and nitrogen compounds that can kill microbes and extend food shelf life without negatively impacting quality. Recent advances allow cold plasma to effectively treat a variety of foods like fruits, vegetables, meat and dairy. While it provides advantages over thermal treatments, challenges remain in processing large or irregularly shaped foods and preventing effects on sensory attributes.
Ohmic heating is an advanced thermal processing method that uses direct resistance heating to heat food products. It works by passing an electric current through the food, with the food itself serving as the resistor to generate heat. Ohmic heating allows for rapid and uniform heating throughout the product at rates of 1-100°C/s. It has advantages over conventional heating like reduced nutrient loss, uniform heating, and faster processing times. Some potential applications of ohmic heating in food processing include meat processing, milk pasteurization, fruit and vegetable blanching, and waste water treatment. However, further research is still needed to fully understand and control the process and address issues like preventing electrolysis during heating.
This case study evaluated the effectiveness of pulsed light (PL) treatment with different spectral compositions on inactivation of Escherichia coli and Listeria innocua on fresh-cut mushrooms. Results showed that treatments with full spectrum PL (180-1100 nm) achieved greater than 3 log and 2 log reduction of E. coli and L. innocua, respectively. Treatments without the UV component showed little to no reduction. Electron microscopy revealed cell damage increased with higher fluence treatments containing UV wavelengths. Thus, the study demonstrated the importance of UV wavelengths, particularly UV-C, for microbial inactivation using PL technology.
Ultrasound processing in dairy industryParth Hirpara
Ultrasound processing has various applications in the dairy industry. Ultrasound uses sound waves with frequencies above the human hearing range to induce cavitation. This can be used for microbial inactivation, homogenization, creaming of milk, and emulsification. The main mechanisms are shear forces and shockwaves generated by cavitation bubbles collapsing near cell walls or interfaces between phases. Process parameters like power, frequency, amplitude, and temperature affect effectiveness. Ultrasound assists filtration by reducing fouling through cavitation effects and has potential to enhance permeate flux.
Ultrasonication processing of fruits and vegetables Gundewadi
1) Sonication is an alternative non-thermal technology to traditional heat processing of fruit juices that provides benefits such as less processing time, higher nutrient retention, and being more energy efficient.
2) Studies have shown that sonication of fruit juices for durations of 30-60 minutes can increase levels of antioxidants like polyphenols and carotenoids while reducing microbial loads.
3) The mechanism of action involves cavitation bubbles forming during sonication that cause cell membrane disruption in microorganisms leading to inactivation without heat.
Microwaves are electromagnetic waves with wavelengths between 1 mm and 1 m that are used for heating. Microwave ovens generate microwaves at a frequency of 2.45 GHz to heat food through rotation and ionic conduction, causing more efficient heating than conventional methods. The key components of a microwave oven are the magnetron which generates microwaves, the waveguide which directs the waves, and the cooking cavity where food is placed. Microwaves are also used for industrial applications like pasteurization, sterilization, drying and heating materials.
Pulsed Electric Field Processing of FoodStella Mariem
The document discusses various process factors that affect microbial inactivation using pulsed electric fields, including electric field intensity, temperature, pressure, and time of exposure. It explains that increasing any of these factors leads to greater inactivation. It also notes different pulse wave shapes that can be used, and describes how the high voltage electric field pulses cause electroporation, making cell membranes permeable and leading to cell death.
This document discusses pulsed electric field (PEF) processing as a non-thermal food preservation technique. PEF uses short, high-voltage electric pulses to induce pores in microbial cell membranes, leading to cell disintegration and microbial inactivation while minimizing negative impacts on sensory and nutritional properties. The document outlines various PEF applications, factors that influence microbial inactivation, commercially available PEF systems, ongoing research needs, and the potential future of PEF processing.
This document discusses several applications of pulsed electric fields (PEF) in food processing, including juice processing, extraction of plant oils and sugars, meat and fish treatment, and microbial decontamination. PEF works by permeabilizing cell membranes through electropermeabilization, allowing for increased mass transfer and extraction of intracellular components. Its applications provide potential to enhance conventional techniques and increase yields while reducing processing times and temperatures.
Radio frequency processing and Microwave heating in food processing prakashsp13
radio frequency and microwave heating ; these slides are explain about its principle and working mechanism ,application in food processing and its advantages .
1) Ultrasonication uses sound waves above the range of human hearing to process foods. It can be used for non-destructive analysis, emulsification, cleaning, and promoting chemical reactions.
2) Piezoelectric transducers are commonly used to generate ultrasound from electrical signals. Cavitation occurs when ultrasound induces the formation and collapse of bubbles in liquids, generating high pressures and temperatures.
3) Ultrasonication is used alone or combined with heat, pressure, or both for pasteurization and sterilization of foods. It inactivates enzymes and microorganisms more quickly than heat alone. Common applications include dairy, fruit and vegetable processing, and meat tenderization.
High pressure processing (HPP) is a non-thermal food preservation technique that uses high water pressure to kill microorganisms and inactivate enzymes in food. This preserves foods without degrading quality attributes like taste, texture and nutrition. HPP was first researched in the 1890s and commercialized in Japan in the 1990s. It is now widely used for products like meat, fish, cheese, juices and ready meals. HPP systems apply pressures of 200-800 MPa for short periods to inactivate pathogens while maintaining food quality. This processing method is gaining popularity with consumers as a safe, natural alternative to thermal pasteurization and canning.
A non thermal processing, which primarily used for homogenisation of fat particles in liquid foods. Now emerged as a promising techniques having applications in food processing. This document will deliver the basics and applications of ultrasound in food
Non thermal processing of food- Pulsed electric field and visible lightT. Tamilselvan
This document provides information on pulsed electric field (PEF) and pulsed visible light processing of foods. PEF uses short electric pulses to preserve foods through electroporation of microbial cell membranes, while minimizing heat production. PEF has been shown to effectively inactivate various microbes in foods like milk, eggs and juices. Pulsed visible light also uses intense, brief pulses of light to inactivate microbes in foods photochemically and through localized heating. Both techniques are non-thermal alternatives to traditional food processing that reduce degradation of nutritional and sensory qualities compared to heat treatments.
Cold plasma is a novel non-thermal food processing technology that uses ionized gas at low temperatures. It generates reactive species like oxygen and nitrogen compounds that can kill microbes and extend food shelf life without negatively impacting quality. Recent advances allow cold plasma to effectively treat a variety of foods like fruits, vegetables, meat and dairy. While it provides advantages over thermal treatments, challenges remain in processing large or irregularly shaped foods and preventing effects on sensory attributes.
Ohmic heating is an advanced thermal processing method that uses direct resistance heating to heat food products. It works by passing an electric current through the food, with the food itself serving as the resistor to generate heat. Ohmic heating allows for rapid and uniform heating throughout the product at rates of 1-100°C/s. It has advantages over conventional heating like reduced nutrient loss, uniform heating, and faster processing times. Some potential applications of ohmic heating in food processing include meat processing, milk pasteurization, fruit and vegetable blanching, and waste water treatment. However, further research is still needed to fully understand and control the process and address issues like preventing electrolysis during heating.
This case study evaluated the effectiveness of pulsed light (PL) treatment with different spectral compositions on inactivation of Escherichia coli and Listeria innocua on fresh-cut mushrooms. Results showed that treatments with full spectrum PL (180-1100 nm) achieved greater than 3 log and 2 log reduction of E. coli and L. innocua, respectively. Treatments without the UV component showed little to no reduction. Electron microscopy revealed cell damage increased with higher fluence treatments containing UV wavelengths. Thus, the study demonstrated the importance of UV wavelengths, particularly UV-C, for microbial inactivation using PL technology.
Ultrasound processing in dairy industryParth Hirpara
Ultrasound processing has various applications in the dairy industry. Ultrasound uses sound waves with frequencies above the human hearing range to induce cavitation. This can be used for microbial inactivation, homogenization, creaming of milk, and emulsification. The main mechanisms are shear forces and shockwaves generated by cavitation bubbles collapsing near cell walls or interfaces between phases. Process parameters like power, frequency, amplitude, and temperature affect effectiveness. Ultrasound assists filtration by reducing fouling through cavitation effects and has potential to enhance permeate flux.
IRJET- Effect of Intensity - Temperature on Ultrasonic Dextran DegradationIRJET Journal
This document discusses an experiment investigating the effect of ultrasound intensity and temperature on the degradation of dextran solutions. Dextran, a polysaccharide produced by bacteria, was sonicated at various intensities (19.2-34.6 W/cm2) and temperatures (10-25°C) for up to 150 minutes. The specific viscosity of the dextran solutions was measured over time using a capillary viscometer to analyze degradation kinetics. Theoretical models were used to determine degradation constants and limit viscosities. The results showed that degradation constants and limit viscosities decreased with increasing intensity and temperature, as higher intensities and temperatures enhanced degradation through cavitation and vapor pressure effects.
Application of ultrasound in pharmaceuticals and food industryRunjhunDutta
Detailed Description of Application of ultrasound in pharmaceuticals and food industry (with examples).
Reference:
Chen, D., Sharma, S.K. and Mudhoo, A. eds., 2011. Handbook on applications of ultrasound: sonochemistry for sustainability. CRC press.
This document provides an overview of ultrasonic therapy. It defines ultrasound as mechanical vibrations beyond the range of human hearing. Ultrasound is used for diagnosis, tissue destruction, and therapy in medicine. Key points covered include the production of ultrasonic waves via piezoelectric crystals, properties of the waves, coupling media, application techniques, parameters like intensity and duration, instrumentation, physiological effects like heating and cavitation, and clinical applications for pain control, soft tissue injuries, and fractures. Precautions for safe and effective use are also discussed.
Processing and Preservation by Non-thermal Methods.pdfshahin211118
This document discusses various non-thermal food processing methods including ohmic heating, pulsed electric fields, high pressure processing, pulsed light, ultrasound, oscillating magnetic fields, and irradiation. It describes the objectives and mechanisms of each method, providing details on how each technique works to reduce microbes while maintaining quality attributes like color, flavor and texture. The conclusion states that non-thermal methods are useful for liquid foods and large-scale production but have high equipment costs, and that reducing costs could enable broader application in small industries.
Ultrasound technology has various applications in food processing as it is a sustainable, non-destructive technology. It can be used to enhance processes like filtration, freezing, thawing, drying, degassing, depolymerization, sterilization, and extraction. In the food industry, ultrasound improves the quality of meat, fruits and vegetables, cereal products, and dairy. It accelerates rates of processes while improving efficiency and product quality over conventional methods.
Aplicación de ultrasonido en tecnologia de alimentosAlba Juárez
This document discusses applications of ultrasound in food technology. It begins by defining ultrasound and classifying its applications into low-energy diagnostic ultrasound and high-energy power ultrasound. Low-energy ultrasound is used for non-destructive analysis of food properties, while high-energy ultrasound can physically or chemically alter foods. The document then reviews several potential applications of high-energy ultrasound in food processing, such as crystallization, degassing, drying, and meat tenderization. It concludes that ultrasound shows promise for developing novel food processing methods.
Ultrasound involves using high frequency sound waves above 20 kHz. It has various applications in industry including food processing. In food processing, ultrasound can be used for tasks like extracting components from foods, homogenizing mixtures, and inactivating microorganisms. It works by generating cavitation bubbles that impart shear forces, breaking up cell walls and improving mass transfer. Key benefits of ultrasound in food processing are that it provides a non-thermal alternative processing method that can help preserve nutritional and sensory qualities of foods.
Radio frequency heating is an emerging technology for food processing that uses electromagnetic energy between 1-300 MHz to induce volumetric heating. It has advantages over conventional and microwave heating such as faster and more uniform heating. The seminar discussed the principles, mechanisms, factors affecting, and applications of RF heating in food industries like thawing, pasteurization, drying, and baking. Research shows RF heating effectively inactivates pathogens in fruit juices, milk, meat and spices without negatively impacting quality.
The document discusses various non-thermal food preservation techniques that can extend shelf life while maintaining quality. It describes techniques like high pressure processing, irradiation, ozonation, ultrasound, pulsed electric fields, and natural antimicrobials. These methods inactivate pathogens and microorganisms using high pressure, radiation, electric fields or natural compounds rather than heat to preserve foods while retaining nutrients and sensory properties. The document also discusses advantages and applications of each technique.
Microwave and radio frequency processing are methods of food processing that use electromagnetic waves. Microwaves range from 300MHz to 300GHz and heat food through dielectric heating and dipole rotation of molecules. Radio frequencies range from 20kHz to 3000GHz and heat food through dipole relaxation and ionic conduction. Both methods allow for uniform and rapid heating of foods. Microwave ovens use magnetrons to generate microwaves for heating while radio frequency equipment uses generators and electrodes. Applications include thawing, baking, pasteurization and drying. Advantages are high efficiency and uniform heating while disadvantages include high costs and difficulty controlling different food types and sizes.
This document summarizes microwave heating and its applications. It begins with an introduction to microwaves and their properties such as their ability to reflect off conducting surfaces and attenuate over short distances. It then discusses advantages like increased bandwidth and improved directive properties. Applications mentioned include telecommunications, radar, microwave ovens for cooking, and industrial uses like drying in textiles. The document provides details on how microwave ovens work and their limitations such as not being able to pass through metal. It concludes with examples of microwave technology used in textile finishing processes for desizing, scouring, bleaching, and drying fabrics uniformly.
This document provides an overview of food irradiation, including its history, uses, principles, units of measurement, types of irradiation sources, safety, and applications. Food irradiation involves exposing food to ionizing radiation like gamma rays or electron beams to destroy microorganisms and insects. It has been used since the early 1900s and allows for extended shelf life and reduced risk of foodborne illness by killing pathogens without raising the food's temperature. Common irradiated foods include spices, wheat, potatoes, and various fruits and vegetables. Doses are typically below 10 kiloGrays. While it reduces spoilage and pathogens, irradiation can also decrease some vitamins and potentially oxidize fats. Overall, international organizations have deemed food irradiation to be
Dr. Shahnawaz Alam discusses applications of high-intensity focused ultrasound (HIFU) and magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) in neurosurgery. HIFU uses focused ultrasound waves to ablate tissue noninvasively and can be used to treat brain tumors, essential tremor, and neuropathic pain. MRgLITT employs laser energy delivered via optical fibers under MRI guidance to thermally ablate lesions while monitoring temperature changes. Both techniques allow precise targeting of intracranial areas for thermal ablation monitored with real-time MRI. Complications include hemorrhage and edema, but HIFU and MRgLITT provide minimally invasive alternatives for selected
Ultrasounds In Food Processing | FoodResearchLabfoodresearch
Ultrasound is considered to be an emerging technology in the food industry. It has advantages of minimizing flavor loss, increasing homogeneity, saving energy, high productivity, enhanced quality, reduced chemical and physical hazards, and is environmentally friendly. Ultrasound is a good alternative method for the food preservation and processing and also no adverse effect on human health.
More info: https://www.foodresearchlab.com/insights/high-power-ultrasound/
Quality control techniques for food safety Jithin Mj
This document discusses various quality control techniques used for food safety, including ultrasound, irradiation, and cold plasma technology. Ultrasound uses sound waves to improve microbial inactivation, food preservation, and food analysis. It can be used at low or high powers for non-invasive analysis or disruptive effects. Food irradiation uses ionizing radiation to eliminate pathogens while maintaining nutritional value. Cold plasma technology uses energized gas to inactivate microbes on food surfaces without heating, providing a potential alternative to thermal processing. The document explores the mechanisms and applications of these techniques to maintain food quality and safety for consumers.
High Power Ultrasounds In Food Processing - FoodResearchLabfoodresearch
Ultrasound is considered to be an emerging technology in the food industry. It has advantages of minimizing flavor loss, increasing homogeneity, saving energy, high productivity, enhanced quality, reduced chemical and physical hazards, and is environmentally friendly. Ultrasound is a good alternative method for the food preservation and processing and also no adverse effect on human health.
More info: https://www.foodresearchlab.com/insights/high-power-ultrasound/
FDA - kinetics of microbial inactivation for alternative food processing tech...Wouter de Heij
This document discusses pulsed electric fields (PEF) technology for non-thermal food preservation. PEF involves applying high-voltage electric pulses to foods placed between electrodes. Studies show PEF can effectively inactivate microbes in foods like apple juice, orange juice, milk, eggs, and pea soup. PEF preserves quality attributes better than thermal processing. However, challenges remain in scaling up equipment and handling issues like air bubbles. Future research is still needed on chemical effects and expanding applications.
FDA - kinetics of microbial inactivation for alternative food processing tech...
Ultrasound.pptx
1. DEPARTMENT OF AGRICULTURAL PROCESSING AND
FOOD ENGINEERING,
SWAMI VIVEKANAND COLLEGE OF AGRICULTURAL
ENGINEERING AND TECHNOLOGY & RESEARCH STATION,
IGKV, RAIPUR
Submitted by
Yogesh Kumar
PhD. I Year
Heat Energy, Ultrasound And Ohmic Heating,
Their Heat Generation , Application And Heating Models
2. Food processing refers to the deliberate transformation of
agriculture produce, through numerous unit operations into more
palatable, shelf-stable, portable and useful, value-added products,
safe for human consumption.
Various traditional processing and preservation methods are still
abundantly and effectively used to process raw food products.
Drying.
Frying.
Smoking.
Salting.
Pickling.
Soaking. etc.
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2
Introduction
3. 3
Foods are complex materials containing proteins, vitamins,
carbohydrates, enzymes, fats, minerals, water and other organic
ingredients with differing compositions.
Processing and preservation of these foods require variety of
different applications/methods and cautions.
Use of ultrasound in food processing includes
•Extraction ,
•Drying ,
•Crystallizatio ,
•Filtration ,
•Defoaming ,
•Homogenization ,
•Meat tenderization ,
Introduction
4. Ultrasound also use of as preservation technique.
Microbial and enzyme inactivation by use of ultrasound makes it
possible to use in food preservation.
Preservation techniques are applied to preserve foods for a long
time and heat treatment is the most widely used method due to its
high efficiency on microbial and enzyme inactivation.
There are a lot of food products that present a threat of bacterial or
viral intoxication for which processing by heat may not be
desirable.
Such thermally sensitive food products on exposure to heat
treatment may undergo physical, chemical, and microbial changes
such as modification of flavor, color, and texture.
4
Introduction
5. Ultrasound is known as a green novel technology due to its role
in environmental sustainability. Sound waves exceeding the
audible frequency range i.e. greater than 20 kHz are termed as
‘Ultrasound’. The lowest ultrasonic limit is 20 kHz (1 Hz = 1 cycle
per second) and the upper limit of ultrasound frequencies for
gases is 5 and 500 MHz for liquids and solids
When the acoustic waves propagate through a medium, they
generate compressions and rarefaction (decompressions) in the
medium particles. This, in turn, produces a high amount of
energy, due to turbulence, and increase in mass transfer.
Ultrasound
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Ultrasonic waves are characterized by their frequency and
wavelength. The product of these parameters is the speed of the wave
through the medium:
c = λf
where c is speed of sound, f is frequency, and λ is wavelength.
The speed of sound increases with the density of the media. Some
advantages of the use of ultrasound in the food industry include
minimization of flavor loss, homogenization effects, and significant
energy saving
7. Ultrasound is an emerging sustainable technology that
enhances the rate of several processes in the food processing
industry, and their efficiency. It can also be applied in
combination with temperature (thermosonication) and
pressure (manosonication) to produce a synergistic effect,
which further enhances its efficacy.
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Ultrasound
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METHODS OF ULTRASOUND
Ultrasound can be used for food preservation in combination with
other treatments by improving its inactivation efficacy. There have
been many studies combining ultrasound with either pressure,
temperature, or pressure and temperature.
1. Ultrasonication
2. Thermosonication
3. Manosonication
4. Manothermosonication
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Thermosonication (TS) is a combined method of
ultrasound and heat.
The product is subjected to ultra- sound and moderate
heat simultaneously.
Thermosonication
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Manosonication (MS) is a combined method in which
ultrasound and pressure are applied together.
Ma- nosonication provides to inactivate enzymes and/or
mi- croorganisms by combining ultrasound with
moderate pressures at low temperatures.
Its inactivation efficiency is higher than ultrasound alone
at the same temperature.
Manosonication
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Manothermosonication
Manothermosonication (MTS) is a combined method of heat,
ultrasound and pressure.
MTS treatments inactivate several enzymes at lower temperatures
and/or in a shorter time than thermal treatments at the same
temperatures.
Applied temperature and pressure maximizes the cavitation or bubble
implosion in the me- dia which increase the level of inactivation.
MTS has been demonstrated to be very effective in inactivation of
enzymes associated with food spoilage which otherwise endure the
conventional thermal treatment.
This method can significantly decrease the activity of many enzymes
like pectin esterase (PE) enzyme of various fruit juices at the
moderate pressure (100-300 kPa) and temperature below 100°C.
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Fig. E. coli K12 cells observed with
environmental scanning electron
microscopy (ESEM): (a) control
(50,000 magnification), (b) and (c)
manosonication at 40 °C and 500 kPa
for 2 min (80,000 magnification), (d)
thermosonication at 61 °C and 100 kPa
for 0.5 min (80,000 magnification), and
(e) and (f) manothermosonication at 61
°C and 500 kPa for 0.25/0.5 min
(50,000 and 80,000 magnification for (e)
and (f), respectively).
Ref - Hyoungill Lee, Inactivation of
Escherichia coli cells with sonication,
manosonication, thermosonication, and
manothermosonication: Microbial
responses and kinetics modeling,
Ultrasonics Sonochemistry Volume
37, July 2017, Pages 216-221
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Fig. Rhodosporidium toruloides cells
observed with scanning electron
microscopy (SEM), 50,000
magnification.
Ref-
A. Meullemiestre, Manothermosonication
as a useful tool for lipid extraction from
oleaginous microorganisms , Ultrasonics
Sonochemistry 37 (2017) 216–221
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Ultrasound waves are classified into four different categories based
on the
mode of vibration of the particles in the medium, with respect to the
direction of propagation of the wave, viz.,
longitudinal waves,
transverse waves,
surface waves, and
plate waves .
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Depending upon/Based on the
intensity (frequency of the
sound ) and frequency
ultrasound waves used in food
application can be categorized
into two categories:
Low intensity ultrasoun and
High-intensity ultrasound.
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Low-Intensity Ultrasound
This is also known as ‘‘diagnostic’’ or ‘‘high-frequency’’ ultrasound,
and involves low-amplitude sound waves. Low-power ultrasound uses
very high frequencies of 100 kHz to 10 MHz or more, with low
sound intensities of 100 mW cm−2 to 1 W cm−2. It measures the
velocity and attenuation of the wave.
Some applications of low-power ultrasound in the food industry are in
processing, quality assurance, and nondestructive food inspections.
food quality assessment (ripeness, composition)
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High-Intensity Ultrasound
produces sound intensities of high power which rank from 10 to 1000
W cm−2, Also known as ‘‘power ultrasound,’’ this uses lower
frequencies (20– 100 kHz) and with amplitudes ranging from 5 to 50
mm .
This kind of ultrasound treatment has enough energy to break
intermolecular bonds. Some applications in food processing
operations include emulsification, homogenization, modification of
viscosity, defoaming, extrusion etc.
23. Generation of ultrasound
The most basic component employed in the generation of ultrasound
is a transducer which converts electrical pulses into acoustic energy of
required intensity.
There are two types of transducers are mainly used for the generation
of ultrasound
Magnetostrictive and
Piezoelectric
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24. A magnetostriction transducer is a device
that is used to convert mechanical energy
into magnetic energy and vice versa. Such
a device can be used as a sensor and also
for actuation as the transducer
characteristics is very high due to the bi-
directional coupling between mechanical
and magnetic states of the material.
Magnetostrictive Transducers act as
electroacoustic transducers for the
generation of ultrasonic waves. These
transducers work on the principle of
magnetostriction which is described as
the subsequent alteration in length per
unit length.
Magnetostrictive Transducers
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25. Piezoelectric Transducer deals with the
inter-conversion of acoustic and
electrical energies.
The working principle of a Piezoelectric
Transducer is based on the fact that
when a mechanical force is applied on a
piezoelectric crystal, a voltage is
produced across its faces. Thus,
mechanical phenomena is converted
into electrical signal. No external
supply is required for this transducer to
work.
Piezoelectric Transducer
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The most commonly produced piezoelectric ceramics are lead
zirconate titanate (PZT), barium titanate, and lead titanate
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Microbial Inactivation
Thermal treatment (i.e. pasteurization, ultra high tem-
perature) is generally considered to be main method for
the inactivation of bacteria but often result in some un-
desirable results such as formation of unwanted flavors
and loss of nutrients.
Nowadays, ultrasound is used for inactivation of
microorganisms to overcome the undesirable results of
thermal processing.
Microbial inactivation mechanisms of ultrasound is
simply explained by cavitation phenomena that caused by
the changes in pressure.
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That the ex- tremely rapid creation and collapse of
bubbles formed by ultrasonic waves in a medium creates
the antimicrobial effect of ultrasound.
During the cavitation process, localized changes in
pressure and temperature cause break- down of cell walls,
disruption and thinning of cell mem- branes, and DNA
damage via free radical production.
In fact, type of bacteria is an important criteria that
changes the effectiveness of an ultrasound treatment.
Different kinds of microorganisms have different
membrane structure.
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Such as, Gram-positive and Gram-negative bacteria do
not show same behaviour against ultrasonic waves due to
their different cell and membrane structures.
Effect of ultrasound on microbial inactivation also de-
pends on intensity and frequency of ultrasound applied.
Generally, frequency range of 200 - 600 kHz enhanced
the effects of ultrasound on microorganisms.
Wordon, et al. suggested that high frequency of
ultrasound was more effective in irradiation of
microorganisms.
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Enzyme Inactivation
Enzymatic reactions produce undesirable changes in
many foods during processing and storage periods.
Heat treatment to eliminate enzymes is the commonly
used method but it also destroys nutrients and may cause
loss of food quality.
For this reason, nonthermal technologies are being tested
as an option for reducing the enzymatic activities in
foods.
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its inactivation mechanism was explained by cavitation.
Since then, it has been proven that ultrasound is an
effective method in the inactivation of enzymes when it is
used alone or with temperature and pressure.
There are many enzymes inactivated with ultrasound
such as
•glucose oxidase ,
•peroxidase ,
•pectin methyl esterase
•protease and lipase
•watercress peroxidase and
• poly- phenoloxidase
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Transmission electron microscopy
FIG 5 TEM photographs of E. coli cells. (a) Untreated
bacteria. (b, c, and d) Bacteria treated with ultrasound for
20 min.
FIG 6 TEM photographs of S. aureus cells. (a) Untreated
bacteria. (b, c, and d) Bacteria treated with ultrasound for
20 min.
33. Application of Ultrasound
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Applications Principle Products
Filtration Vibrations Liquid food products eg.
Juices
Freezing / Crystallization Uniform Heat Transfer Milk products
Fruits & Vegetables
Meat
Thawing Uniform heat Transfer Frozen products
Brining/Pickling Cheese, meat, fish etc
Drying Uniform Heat Transfer Dehydrated Food Products
Foaming Dispersion of gas bubbles Protein
Degassing / Deaeration Agitation Carbonic beverages, aqueous
solutions.
Cooking Uniform Heat Transfer Meat Products
Vegetables
Emulsification Cavitation Phenomenon Emulsions eg. Mayonnaise
Cutting Cavitation Phenomenon Soft Products eg. Cheese,
Bread
Sterilization / Pasteurization Uniform Heat Transfer Milk, Juice
Extraction Diffusion Food and plant material
Rehydration Absorption Dried vegetables, grains etc.
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Heat generation : electrical resistance heating
The need to conduct heat is the limiting factor in the
sterilization of particles. Volumetric techniques, in which
heat is generated with In the material , offer ways of
circumventing the problem.
It is possible to generate heat using microwave heating
[4],in which a high-frequency electric field excites the
water molecules within the material, or by electrical
resistance heating ('ohm cheating').
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The principle of electrical resistance heating is shown in
Figure10.1. In this process, an electric current is passed
through the material, which then heats throughout its
volume, as a result of its electrical resistance.
The process is more energy efficient than microwave
heating, because nearly all of the electrical energy goes in
to the food as heat.
Whereas microwave heating requires no physical
contact, however, resistance heating requires electrodes
in good contact with the food.
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Advanced Thermal Processing Technique :
Ohmic Heating
Ohmic heating is an advanced thermal processing
method where in the food material, which serves as an
electrical resistor, is heated by passing electricity through
it.
Electrical energy is dissipated into heat, which results in
rapid and uniform heating.
Ohmic heating is also called electrical resistance heating,
Joule heating, or electro-heating.
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Principles of Ohmic Heating
Ohmic heating is based on the passage of
alternating electrical current (AC) through a
body such as a liquid-particulate food system
which serves as an electrical resistance in which
heat is generated.
The rate of heating is directly proportional to
the electrical conductivity.