Ultrasonic Honey Processing

Honey enjoys great demand as food and medicine. Ultrasonic processing is an effective means to destroy undesirable components, such as crystals and microbial cells in honey. As a non-thermal processing technology, ultrasonic honey decrystallization prevents undesired increase in HFM as well as better retention of diastase, aroma and flavor.

Advantages of Ultrasonic Honey Decrystallization

Ultrasonic decrystallization is an efficient alternative to traditional heating methods for honey decrystallization. Ultrasonic honey decrystallization offers numerous advantages over the conventional heating method, which makes ultrasonic honey processing the superior treatment for honey liquefaction, decrystallization and stabilization:

Ultrasonic decrystallization offers several advantages and can be adapted to all honey types and production scales. Hielscher ultrasonicators are precisely controllable and can be tuned to factors such as honey viscosity, crystal size, and quality standards. Thereby, Hielscher ultrasonicators provide high effectiveness and simple, safe operation.

Ultrasonic Honey Processing

Ultrasonication is a non-thermal processing alternative for many liquid food products. Its mechanical power is being used for a gentle yet effective microbial inactivation and particle size reduction. When honey is exposed to ultrasonication, most of the yeast cells are destroyed. Yeast cells that survive sonication generally lose their ability to grow. This reduces the rate of honey fermentation substantially.
Ultrasonication also liquefies honey eliminating existing crystals and inhibiting further crystallization in honey. In this aspect, it is comparable to heating the honey. Ultrasonically aided liquefaction can work at substantially lower process temperatures of approx. 35°C and can reduce liquefaction time to less than 30 seconds. Kai (2000) studied the ultrasonic liquefaction of Australian honeys (Brush box, Stringy bark, Yapunyah and Yellow box). The studies showed, that sonication at a frequency of 20kHz liquefied the crystals in the honey, completely. Ultrasonically treated samples remained in liquefied state for approx. 350 days (+20% when compared to heat treatment). Due to the minimal heat exposure, ultrasonic liquefaction results in a greater retention of aroma and flavour. Sonicated samples show only a very low HMF increase and small decrease in diastase activity. As less thermal energy is needed, the application of ultrasound helps to save processing costs when compared to conventional heating and cooling.

The studies of Kai (2000) also revealed, that different types of honey require different intensities and times of sonication. For this reason, we recommend the conduct of trials using a bench-top size sonication system. Preliminary tests should be conducted in batch mode, while further processing trials require a flow cell for pressurized recirculation or in-line testing.

What Research says about Ultrasonic Honey De-Crystallization

Honey is a supersaturated solution of glucose and it has a tendency to crystallize spontaneously at room temperature in the form of glucose monohydrate. Heat treatment has been employed traditionally to dissolve D-glucose monohydrate crystals in honey and delay crystallisation. However, this approach negatively affects the fine-spun flavour of honey. The beneficial application of power ultrasound in honey has been reported by many researchers. The application of ultrasound has been shown to eliminate existing crystals and also retard the crystallisation process resulting in a cost-effective technology. Analysis of the crystallisation process suggests that sonicated honey samples remained in liquid state for longer periods than heat-treated honey. In addition, no significant effects on honey quality parameters, such as moisture content, electrical conductivity or pH, were observed. Studies have shown that, in general, ultrasound treatment (e.g. with a 24 kHz ultrasonic probe of the model UP400St, in batch treatment) leads to faster dissolution of crystals than thermal treatment.
(cf. Deora et al., 2013)
Basmacı (2010) compared ultrasonication and high-hydrostatic pressure as treatment options for honey liquefaction. Whilst the high-hydrostatic pressure treatment was shown as too expensive and ineffective, ultrasound gave very good results. Therefore, sonication was recommended as alternative for traditional thermal processing of honey.
Önur et al. (2018) came to the same conclusion when comparing conventional heat treatment at 50ºC, ultrasonic liquefaction and They recommend ultrasonic honey processing over thermal processing and pressure treatment owing to the convenience, shorter processing times, and less quality loss.
Sidor et al. (2021) compared ultrasonic liquefaction with microwave heating in order to dissolve sugar crystals in lime, acacia and multifloral honeys. A major disadvantage of the microwave heating were the significantly increased HMF values, changes in enzymatic activity and large diastase number losses. In contrast ultrasonic liquefaction resulted in only smallest changes in honey properties, so that the research team clearly recommended the ultrasonic honey processing in order to delay the crystallization process.
accelerate the liquefaction time of solid honeys without compromising its quality.

High-Performance Ultrasonicators for Honey Decrystallization and Stabilization

Hielscher Ultrasonics manufactures and supplies high-performance ultrasonicators for liquid food processing such as honey liquefaction, crystal reduction (sugar dissolving, decrystallization) and microbial stabilization. Specially developed ultrasonic equipment for honey treatment allows for uniform and reliable processing. This assures the production of superior honey at maintained quality standards. For the treatment of honey, Hielscher Ultrasonics offers special sonotrodes (ultrasonic probes), which are ideal for the very uniform treatment of viscous liquids such as honey.

Design, Manufacturing and Consulting – Quality Made in Germany

Hielscher ultrasonicators are well-known for their highest quality and design standards. Robustness and easy operation allow the smooth integration of our ultrasonicators into industrial facilities. Rough conditions and demanding environments are easily handled by Hielscher ultrasonicators.

Hielscher Ultrasonics is an ISO certified company and put special emphasis on high-performance ultrasonicators featuring state-of-the-art technology and user-friendliness. Of course, Hielscher ultrasonicators are CE compliant and meet the requirements of UL, CSA and RoHs.

The table below gives you an indication of the approximate processing capacity of our ultrasonicators: