Do you know Ultrasonic Honey Crystallization?

Ultrasonic Honey Crystallization: A "Gentle Deconstruction" Technology to Preserve Natural Flavor

Honey crystallization is a natural physical phenomenon in which glucose precipitates in the form of crystals. While this does not alter the intrinsic quality of the honey, it can cause the honey to become hard, making it difficult to package, and potentially reducing consumer acceptance due to the altered appearance. Traditional heating methods often sacrifice the active nutrients of honey due to high temperatures. Ultrasonic crystallization, with its core advantage of being a "non-thermal process," has become a new solution for the deep processing of honey, providing a "quality shield" for natural honey.

I. The Nature of Honey Crystallization and the Need for Crystallization
Honey's crystallization properties stem from its composition—glucose accounts for over 40% of the total sugar content and has a low solubility in water. When stored at a temperature within the "critical crystallization zone" of 13-14°C, glucose gradually forms needle-shaped or clustered crystals around the crystal nuclei. For honeys with a high glucose content, such as gallnut honey, crystallization can lead to hardening, making it difficult to dissolve during consumption and hindering industrial processing steps such as filtration and bottling. The core requirement for crystallization is to maximize the preservation of heat-sensitive nutrients in honey, such as amylase, vitamins, and flavonoids, while simultaneously destroying the crystal structure. Traditional methods like water bath heating and hot air heating have fatal flaws: low temperature control precision and frequent high temperatures exceeding 60°C. This leads to rapid inactivation of amylase activity and increased hydroxymethylfurfural (5-HMF) content, directly affecting honey quality. This "quality for form" approach is no longer able to meet modern consumers' demand for natural foods.

II. Technical Principles and Core Advantages of Ultrasonic Crystallization
Ultrasonic crystallization technology utilizes mechanical waves with a frequency of 16kHz to 10MHz to act on crystallized honey. The synergistic effects of cavitation and thermal effects decompose the crystals. Its core advantage lies in its balance of "high-efficiency crystallization and low-temperature quality protection."

Technically, ultrasound converts electrical energy into mechanical vibrations through a transducer, generating a large number of tiny cavitation bubbles in the liquid honey. These bubbles expand rapidly and burst instantly during the vibration cycle, generating intense shear forces and turbulence that directly break up the tightly packed glucose crystals, breaking them into fine particles and redissolving them. Simultaneously, ultrasonic vibrations generate a gentle thermal effect, slowly raising the honey temperature (typically to no more than 60°C), further promoting crystal dissolution. However, unlike traditional heating, the heat is evenly distributed and the temperature rise is controlled, avoiding localized overheating. Research from the Chinese Academy of Agricultural Sciences shows that after 80 minutes of treatment at a frequency of 40kHz and a power of 400W, the crystal dissolution rate of loquat honey can reach 98.2%. The crystal structure transforms from clusters to small blocks, ultimately dissolving completely into a liquid state.

Compared to traditional methods, ultrasonic crystal disruption offers significant advantages:

More complete quality preservation: Under gentle treatment, the loss of heat-sensitive components is significantly reduced. Experiments have shown that after 80 minutes of ultrasonic treatment, the amylase activity in loquat honey decreased by only 8.94%, while traditional heating methods often lose over 30% of enzyme activity over the same period of time. Improved crystal breaking efficiency and stability: Not only does it accelerate crystal breaking, it also changes the rheological properties of honey, transforming it from a non-Newtonian fluid to a uniform Newtonian fluid, significantly reducing viscosity and facilitating subsequent processing.

Additional benefits: The mechanical effect generated during crystal breaking also acts as a low-temperature sterilizer, effectively killing osmophilic yeasts in honey and extending its shelf life.

Delayed recrystallization: By disrupting the crystal nucleus structure, it can lower the crystallization point of honey from the natural 13-14°C to below 0°C, preventing crystallization for over five years at room temperature.