Honey Warming Equipment

A honey warming tank is a vessel, usually stainless steel, that brings crystallised (set) honey back to a consistency that can be filled into jars by warming it slowly and to a limited temperature, not over a direct flame but with a warm water jacket, a warming cabinet or a thermostatic heater. Used wrongly, it is the riskiest piece of post-harvest equipment, damaging the honey's enzymes and raising its HMF value. This page covers warming methods, safe temperature principles and how to choose a tank.

Why is honey warmed? Crystallisation is not spoilage

Honey is a solution carrying far more sugar than can stay dissolved in its water. Over time some of the glucose separates out as crystals and the honey sets. This is called crystallisation; in everyday speech it is also called “granulation” or “setting”. Crystallisation is a natural property of honey, not a sign of adulteration or spoilage. Honeys high in glucose (e.g. sunflower, oilseed rape) set within weeks, while honeys high in fructose (e.g. acacia, chestnut) set much later.

Warming is needed in these cases:

• Filling: Transferring honey that has set in a bucket or drum into jars.
• Preparing creamed honey: Making the honey completely liquid before controlled crystallisation.
• Straining: Getting honey that has started to set in a tank or bucket through a strainer.

Selling crystallised honey to consumers is also entirely legitimate. Warming is not compulsory; it is a choice.

What does warming do to honey? HMF and enzymes

Honey is sensitive to heat. As temperature and time increase, two important changes occur:

• HMF rises: Hydroxymethylfurfural (HMF) is a compound formed from sugars with heat and time. It is low in fresh honey and rises with warming and with long, warm storage. In the Turkish Food Codex (in Türkiye) and in international standards the general limit is 40 milligrams per kilogram.
• Enzymes break down: Diastase and invertase, which the bees add to honey, lose their activity with heat. The diastase number is also a legal quality criterion; overheated honey may fail to meet it.

The effect depends on time as much as on temperature. Both brief high heat and prolonged gentle heat cause damage. The colour darkens and the aroma flattens. So the rule is: the lowest possible temperature, for the shortest time needed.

Types of honey warming tank

Double-walled (water-jacketed) tank

It consists of two tanks, one inside the other. The space between them holds water; the heater warms the water, and the water warms the honey. The heat is gentle and evenly distributed, and a thermostat limits the water temperature. Because there is no direct contact between the honey and the heating surface, no hot spots form.

Warming cabinet (hot box)

An insulated, thermostatic cabinet or room. Buckets and jars are placed inside and warmed slowly by warm air. Because it liquefies honey without changing containers, it is the most practical method for small and medium operations. There should be air circulation inside the cabinet, and the temperature should be measured at the level of the honey.

Bucket and drum heating belts

Thermostatic heating jackets wrapped around a bucket or drum, or heating plates placed underneath. They are practical, but the heat comes from one surface; unless the thermostat is kept low, the honey close to the heater overheats.

Bain-marie (water bath)

For small quantities: jars are placed in a container of warm water. The water level must stay below the lid, the water must not boil, and it should be monitored with a thermometer.

What should you look for when choosing a honey warming tank?

1. Material: The surface in contact with honey must be stainless steel. Aluminium can corrode with prolonged contact with acidic honey; galvanised or painted surfaces are not acceptable.
2. Indirect heating: The heater should not be in direct contact with the honey; a water jacket or warm air is preferred.
3. Precise thermostat: A thermostat that works accurately at low temperatures, with a readable setting. If possible, a separate temperature probe that goes into the honey.
4. Overheat protection: A safety thermostat that cuts the circuit if the main thermostat fails.
5. Stirring: In large tanks a slowly rotating stirrer evens out the heat; fast stirring adds air to the honey.
6. Honey gate and cleaning: A wide honey gate, removable parts, a smooth interior.
7. Electrical safety: Electrical parts protected against splashes of water and honey, and an earthed socket.

How do you liquefy crystallised honey step by step?

1. Check the moisture: If there is a watery layer, foam or a sour smell on the surface of the set honey, fermentation may have started. Warming does not fix fermented honey.
2. Prepare the container: Loosen the lid of the bucket or jar slightly and clean the outside.
3. Start at a low temperature: Set the cabinet or jacket to a value close to hive temperature.
4. Be patient: A large bucket can take hours, even several days. Do not try to shorten the time by raising the temperature.
5. Stir gently: Once it starts to liquefy, stirring the honey gently evens out the heat. Take care not to add air.
6. Liquefy completely, fill immediately: If crystal residues remain, the honey soon sets again. Take the fully liquid honey off the heat and fill it; do not leave it standing on the heat.

Warming and cooling for creamed honey

Creamed honey is honey crystallised in a controlled way with fine, smooth crystals, to a spreadable consistency. To prepare it, the honey is first slowly and completely liquefied, then mixed with a finely crystallised “seed honey” and left in a cool place. Here the warming tank is only the first step; the real quality comes from crystallisation at a cool, stable temperature.

Common mistakes

• Warming honey on the stove, over a direct flame or in a microwave.
• Setting the thermostat high to try to shorten the time.
• Leaving liquefied honey on the heater for hours.
• Putting a heating plate under a bucket and leaving it unattended.
• Trying to “rescue” fermented honey by warming it.
• Using an aluminium or galvanised tank.