IMPACT OF ULTRASOUND ON PROCESS EFFICIENCY IN FOOD INDUSTRY

Transcription

1 IMPACT OF ULTRASOUND ON PROCESS EFFICIENCY IN FOOD INDUSTRY Mladen Brnčić Faculty of Food Technology and Biotechnology Zagreb Croatia

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4 Sound waves at frequencies higher than the audible range (16 khz)

5 Power ultrasound ( khz) can be used for IMPROVING PROCESSING EFFICIENCY Enhancing drying Enhancing extraction Enhancing homogenisation Defoaming Enhancing emulsification Viscosity modification Enhancing oxidation processes

6 ULTRASOUND PROCESSING OF FOODS PHENOMENON OF CAVITATION The basis of ultrasound benefits LIQUIDS - Consequence of L-wave creation leads to alternate cycles of expansion and rarefaction Areas of pressure changes causes cavitation occurence during which bubbles are formed with higher surface area under expansion cycle Cavitational bubble is growing and shrinking during dynamical phases equilibrium during phase within bubble and liquid outside EXAMPLE - 24 khz; Critical size of cavitational bubble is 170 µm and in that moment bubble is not able to absorb energy and IMPLODE

7 ULTRASOUND PROCESSING OF FOODS Ability of ultrasound to form cavitation depends on its properties: frequency, intensity, amplitude Device properties and geometry: Maximal nominal output power, cycle adjustment, diameter of sonotrodes (probes) Treated material properties: Viscosity, particle size and particle size distribution, surface tension, texture and composition Surrounding conditions: Temperature, moisture, pressure With very high frequencies ( >1 MHz) it is difficult to achieve cavitation effect and above 2,5 MHz IMPOSSIBLE

8 PHENOMENON OF CAVITATION STABLE CAVITATIONS TRANSIENT CAVITATIONS - WATER COLD BOILING

9 ULTRASOUND PROCESSING OF FOODS PHENOMENON OF CAVITATION TRANSIENT CAVITATIONS - BOILING (WITH IMPLOSION delivering of bubble energy within surrounding microenvironment )

10 ULTRASOUND PROCESSING OF FOODS Frequency vs. Intensity Cavitational paradox LESS FREQUENCY WITHIN ULTRASONIC RANGE MORE AGRESSIVE EFFECT

11 ULTRASOUND PROCESSING OF FOODS Hi intensity ultrasound (HIU) Applications in Food Technology: EMULSIFYING DRYING EXTRACTION HOMOGENIZATION CRYSTALLIZATION SPRAYING/COATING FREEZING CLEANING INACTIVATION OF MICRORGANISMS ENZYME ACTIVATION AND INHIBITION DEFOAMING AIR BORN DEBLINDING AIR BORN CUTTING AIR BORN

12 ULTRASOUND PROCESSING OF FOODS: Drying, homogenization and extraction in foods assisted by ultrasound RESULTS 3 DOCTORAL THESIS DEFENDED SVEN KARLOVIĆ US ASSISTED DRYING TOMISLAV BOSILJKOV US ASSISTED HOMOGENIZATION MAJA DENT US ASSISTED EXTRACTION

13 ULTRASONICALLY AIDED DRYING Food drying is one of the oldest, very simple, and very meaningful ways of preserving foods

14 ULTRASONICALLY AIDED DRYING Experimental research Doctoral thesis SVEN KARLOVIĆ - defended Apple slices 3 x 2 x 0.5 cm respectively Hypotesis Improved mass transfer Enhanced textural properties Shortening of drying procedure Decreased costs Lower energy consumption Microvawe dryer Tunnel dryer (hand made)

15 ULTRASONICALLY AIDED DRYING Ultrasonic propagation could cause numerous series of alternative compressions and expansions, like pressing and releasing of a sponge (sponge effect). The mechanical forces created are higher than surface tension which withold the moisture inside the capillaries of the fruit creating microscopic channels which may ease moisture removal.

16 ULTRASONICALLY AIDED DRYING Environmental aspects Clean technology No moving parts Shortening drying time 40% of saved energy Improved food Quality Low noise No waste material No waste water

17 ULTRASONICALLY AIDED DRYING Apple sample before and after ultrasonic treatment

18 ULTRASONICALLY AIDED DRYING Texture results Hardness Elasticity Work

19 ULTRASONICALLY AIDED DRYING Conclusions SO FAR!!! Ultrasonic pre-treatment of apple pieces before drying enables shorter time of drying Increase of ultrasonic intensity additionally lead to more time shortening of drying Removal of higher amounts of water from ultrasonically treated samples is enabled for the shorter duration of drying Amplitude of 50% indicates as adequate with achieved results for ultrasonic pre-treatment of apple pieces HARDNESS + Under maximum of ultrasonic amplitude treatment and after drying of such pre-treated samples to large hardness of the samples occurred whereby those parameters of pre-treatment were not suitable Improved elasticity ELASTICITY - More time for chewing WORK +

20 ULTRASONICALLY AIDED HOMOGENISATION

21 ULTRASONICALLY AIDED HOMOGENISATION Hypothesis Size reduce of fat globules Improvesd homogenisation Improved stability Prolonged shelf life Energy savings Milk homogenisation Material Cow, goat and soy milk PhD thesis Tomislav Bosiljkov (Cow milk)

22 ULTRASONICALLY AIDED HOMOGENISATION METHOD 1 A 30, 60, 90 t (5; 7.5; 10) Cycle 1 d 10 mm V 400 ml Im.depth 3 cm METHOD 2 A 30, 60, 90 t (5; 7.5; 10) Cycle 1 d 7 mm V 400 ml Im.depth 3 cm

23 ULTRASONICALLY AIDED HOMOGENISATION Inhomogenised milk Descript ive statistic s Mode Median Mean value Variance Maximu m

24 ULTRASONICALLY AIDED HOMOGENISATION A = 90 %; t = 10 min; d (probe) = 7 mm A = 90 %; t = 10 min; d (probe) = 10 mm

25 ULTRASONICALLY AIDED HOMOGENISATION A = 90 %; t = 10 min; d (probe) = 7 mm A = 90 %; t = 10 min; d (probe) = 10 mm

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27 ULTRASONICALLY AIDED HOMOGENISATION

28 ULTRASONICALLY AIDED HOMOGENISATION Milk homogenisation CONCLUSIONS Results were analyzed and compared The best results were obtained with treatment time of 10 min for both US devices Sonotrode diameter had significant influence due to dispersion of cavitaional cloud i.e. intesities Decreased time of treatment with increase of US amplitude increased intensities Less energy consumption compared with conventional homog. No moving parts cheaper amortization More uniform particle size distribution of fat globules prolonged shelf life Milk, Ketchup, Dressing, Juices, Sauces, Mayonaise

29 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS Material Sage PhD thesis Maja Dent Mechanical effect of US: Disruption of cell walls of the plant Enable easier release of cell compounds Better solvent admission to cell compounds Improved mass transfer Energy savings

30 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS PROCESS OPTIMIZATION Ultrasound Frequency Acoustic power Cycle Amplitude EXTRACTION Treatment time Temperature SOLVENT Particle size ph SOLVENT Selelective for targeted compounds Severe extraction capacity not be reactive with other plant compounds Inoffensive for the people and equipment Completely volatile Economical (low price)

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32 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS

33 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS Total phenols - SAGE Conventional extraction - 60 C Extraction time 30 min Solvent 30% Ethanol 30% Acethone Water TP (mg GAE/ g dry sage)

34 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS Total phenols Sage ULTRASONIC EXTRACTION A-100% C-1 SOLVENT 30% Ethanol Sonotrode 7 mm 22 mm Extraction time (min) TP (mg GAE/ g dry sage)

35 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS Conventional extraction - 60 C Extraction time 30 min Solvent 30% Ethanol 30% Acethone Water TP (mg GAE/ g dry sage) SONOTRODE ULTRASONIC EXTRACTION A-100% C-1 22 mm EXTRACTION T. 11 (min) SOLVENT 30% ETHANOL 30% ACETHONE WATER TP (mg GAE/ g dry sage)

36 ULTRASOUND ASSISTED EXTRACTION OF BIOACTIVE COMPOUNDS Advantages of ultrasonic extraction v.s. classic extraction: INCREASED YIELD Enhanced extraction rate Extraction conducted under lower temperatures - enhance extraction of heat sensitive components. Enhancement of extraction processes where solvents cannot be used (juice concentrate processing) Potential opportunity for aqueous extraction or use of alternative solvents by improving their performance Less creation and release of heat Ecologically more acceptable method sustainable food innovation Commercially viable and scaleable

37 ULTRASOUND PROCESSING OF FOODS: Drying, homogenization and extraction in foods assisted by ultrasound - Comparision and advantages over traditional food processing Shorter processing of foods - Low increase of temperature - Energy savings - Improved food quality - Decresed amount of emulsifiers - Increased yield - Improved texture and structure - Ecologically more acceptable method sustainable food innovation - No toxic waste

38 DEFOAMING ultrasound technology for use in the food and beverage industry the foam issues present in the majority of beverage filling lines easy to install, safe and cost-effective method of removing foam by removing the need for chilling or slower line speeds there are productivity improvements for carbonated soft drinks, non-carbonated juices, teas, dairy drinks, sparkling wine, carbonated alcoholic pre-mixes or beer the solution can be applied all sizes of can, bottle and pouch containers on aseptic or hot fill lines. it is not expensive to operate and it doesn t affect the quality or taste of the product

39 SPRAY DRYING OF PROTEINS- reduction of viscosity Ultrasound technology can modify the fluid dynamics of the protein concentrate stream feeding the spray dryer, allowing for higher concentration and percentage dry solids into the dryer. It uses efficient, high-energy sound waves to deliver one or more of the following mechanisms: Remove entrained air and oxygen bubbles Open up the compaction layers of the proteins Temporarily reduce viscosity Create a temporary change in the protein molecule alignment What are the benefits? In addition to reducing energy consumption, the ultrasound technology: increases output by 10% reduces overall fixed and variable cost reduces filling losses and waste treatment costs reduces chilling requirements reduces capital costs and increases profits provides payback in under one year

40 THE ULTRASOUNDS CLEANING PROCESS designed specifically for each application to optimize performance and total cleanness. different temperature, frequency and chemical combinations are used. Determination of the best process parameters for each problem (dirt, grease or coal dust adhered to the surface of the object) Temperature: Temperature increases (80-90ºC) in liquids augment steam pressure and facilitate the presence of bubbles (Cavitation). This results in increased cleaning power. Frequency: It determines the size of the bubbles generated during Cavitation. High dirt levels require lower frequency levels, with higher power. High frequency levels are used for finishing operations or to clean delicate components (Optics). Chemicals: Each application requires a certain chemical and concentration level based on factors such a working temperature, type of dirt, cleaning time and material. Ultrasound waves optimize the effects of the cleaning agents, thus reducing the level of chemicals needed. A suitable combination of the above named parameters significantly reduces cleaning time, which is the fourth parameter of the Ultrasounds Cleaning Process.

41 Ultrasounds cleaning systems are based on high-frequency sound waves transmitted through a cleaning liquid. The component to be cleaned is submerged into the cleaning liquid. The treatment lasts between 10 and 45 minutes and does not require the presence of any laborer. The result is a micro-brushing effect on the objects. Since the air bubbles are smaller than 1µm, they get into any openings, regardless of their size. Therefore, ultrasound cleaning is the most suitable cleaning system for highly complex components of any material (alloys, steel, alluminium, copper, bronze, titanium, certain plastic types etc

42 LAB SCALE RESEARCH SCALE UP SEMI INDUSTRY (SMES) INDUSTRIAL LABORATORY FOR UNIT OPERATIONS R & D CENTRE FOR ULTRASOUND APPLICATIONS IN FOOD TECHNOLOGY & BIOTECHNOLOGY

43 IMPACT OF ULTRASOUND ON PROCESS EFFICIENCY IN FOOD INDUSTRY ACKNOWLEDGMENT Dr. Nada Knežević Dr. Davorka Gajari Society of Chemists and Technologists of Koprivnica Podravka Food Company

44 IMPACT OF ULTRASOUND ON PROCESS EFFICIENCY IN FOOD INDUSTRY THANK YOU FOR YOUR ATTENTION Mladen Brnčić Faculty of Food Technology and Biotechnology Zagreb Croatia