Ultrasonic Freezing and Ice Crystallization of Food Products
- Sonication increases the nucleation of ice crystals and provides thereby a faster freezing and control over the ice crystal size.
- Power ultrasound is beneficial to many food-freezing processes as shorter freezing times and leads to higher product quality.
- Ultrasonically assisted freezing finds manifold applications in the food and pharmaceutical industry.
Ultrasonic Food Freezing
- promotes the nucleation of ice
- retains better microstructure
- more uniform sized crystals
- small intracellular ice crystals
- shortens the process time
- enhances the extent of ice nucleation
- reduces crystal induction time
- causes a more uniform crystal growth
- breaks down any ice dendrites
- enhances the heat and mass transfer
- chemically non-invasive
- accelerates freezing rate
- improves quality
- smaller ice crystals and uniform crystal size distributions
- induces crystal fragmentation
- prevents incrustation on the freezing surface
- decreases freezing time
- improves sensory flavor, texture and mouth feel
- easy and safe to operate, modify and control
- cost-effective
Ultrasonics Ice Cream Production
The positive influence of power ultrasound on freezing processes was successfully proven by sonicating ice cream. The ultrasonic treatment causes a faster freezing process and a smoother ice cream texture since the ultrasonic cavitation breaks the ice crystals.
The freezing time can be reduced about 35% in ice cream processing, which saves time and energy for the freezing treatment and results in a better food product as the ice crystals are reduced significantly resulting in a smoother, finer texture.
Besides the enhances freezing, high intensity, low frequency ultrasound is a very effective technique to homogenize and blend the ingredients to an even, uniform formulation.
Hielscher’s ultrasonic food processors are available for any process scale.
Ultrasonic Food Processing Equipment
Ultrasonic homogenizers are widely used for manifold applications in the food processing industry. Hielscher supplies ultrasonicators for the treatment of food products such as convenience food, dairy, food ingredients, and nutraceuticals & supplements. The sonication provides improved mixing, preservation, product stability & shelf-life, digestion, and taste. Hielscher’s ultrasonic processors are equipped with CIP (clean-in-place) and SIP (sterilize-in-place) technology, thus they can be safely installed at all sanitary process stages.
Since ultrasound improves the extraction of flavours and assists stabilization & preservation, the amount of required additives can be significantly reduced, too.
Hielscher’s ultrasonic devices and systems cover the full range from small and mid-sized bench-top food processors to fully industrial plant equipment. Our ultrasonicators can be installed for batch processing or can be integrated inline in continuous production streams.
Literature/References
- Awad, T.S.; Moharram, H.A.; Shaltout, O.E.; Asker, D.; Youssef, M.M. (2012): Applications of ultrasound in analysis, processing and quality control of food: A review. Food Research International 48,2012. 410-427.
- Dairy Processing Handbook. Published by Tetra Pak Processing Systems AB, S-221 86 Lund, Sweden. p. 387.
- Mortazavi, A.; Tabatabaie, F. (2008): Study of Ice Cream Freezing Process after Treatment with Ultrasound. World Appl. Sci. J 4, p. 188-190.
- Petzold, G; Aguilera, J. M. (2009): Ice Morphology: Fundamentals and Technological Applications in Foods. In: Food Biophysics Vol.4, No. 4, p. 378-396.
- Zheng, L.; Sun, D-W. (2006): Innovative applications of power ultrasound during food freezing processes — A review. Trends in Food Science & Technology 01/2006.
Ultrasonic Food Processing – Almost Unlimited Applications
Ultrasonic homogenization is applied to reduce the particle size of liquid and pasteous products such as milk, fruit juice and sauces. The desired mixing, blending and milling effects are achieved by the intense ultrasound, which creates extreme pressure, shear, micro-turbulences, acceleration, liquid jets and interparticular collision. Power ultrasound applied to food products results in homogeneous, fine-sized textures and intense flavours.
Besides the mixing application, ultrasound can contribute to the direct or indirect heating of the product. If the product is heat sensitive, a sophisticated cooling of the process can be easily ensured.
- Extraction
- Stabilization & Preservation
- Spray Drying
- Deaeration & Defoaming
Ultrasonic food processing includes the following produces amongst others: baby foods, butter, margarine & butter oil (maillard), casein, whey & milk proteins, chocolate, confectionary & sweets, milk, cream, cheese & yogurt, ice cream, egg & egg yolk, fish oil, chitosan & chinin, flavors & condiments, fruit and vegetable juices, smoothies & purees, fruit pulps & concentrates, gelatine, guar gum, xanthan & gum arabic, honey, ketchup & tomate sauce/paste, meat, meat paste & sausages, frozen convenient products, vitamins & active substances, soy products, yeast (fermentation products), syrups & sugar solutions, spreads, jam, marmalade & confiture, tomato juice & clamato, tomato concentrate, beverages, wine, spirits & liquors etc.