Introduction: Electric and steam heating move heat into jelly candy syrup in different ways, and their published installed power ranges show why factory utilities matter more than the number alone.
Anyone planning a jelly candy line eventually meets the same question: should the melting and holding stage run on electricity or on steam? The two options are not different flavours of the same decision. One builds the heat source into the machine, the other pipes heat in from a boiler house, and that single difference ripples through power supply, piping, control logic and daily operation. Published specifications for jelly candy production lines show electric heating variants carrying 60 KW to 280 KW of installed power, while steam heating variants sit between 35 KW and 180 KW. The gap between those two ranges is not a statement about which method performs better. It reflects where the heat is actually generated, and what the factory has to provide to make it flow.
In a jelly candy line, the melting stage takes sugar, glucose syrup, water and gelling agents and turns them into a uniform, pourable syrup. The holding stage keeps that syrup at a stable temperature and viscosity until the depositing machine is ready for it. Electric heating places the entire heat source inside this flow of work. Power arrives at the melting pot and the holding tank, and the equipment converts it into heat at the vessel itself. Temperature sensors feed back to the controller, which adjusts how much energy the vessel receives. Nothing upstream of the machine has to produce heat, and nothing outside the workshop has to deliver it.
Electric heating works because a defined electrical load produces a defined amount of heat, and that heat moves through the vessel wall into the syrup. The melting pot carries the heaviest load because it has to raise cold ingredients to melting temperature and dissolve solids. The holding tank carries a lighter load, mostly compensating for heat lost through the tank surface, which is why insulation pays off in the holding stage. Because the heat source sits directly on the vessel, the control loop is short: the sensor reads syrup temperature, the controller adjusts power, and the response is quick. Batch control thinking helps here, since melting, holding and transfer are separate stages with their own temperature targets and end conditions, and each stage can be managed as its own module.
Electric heating turns the whole thermal load into an electrical load. That is why the published installed power for electric variants reaches 280 KW on the largest jelly candy models, and starts around 60 KW on the smallest ones. This figure covers melting and holding, along with pumps, drives and the control cabinet. It shapes the electrical work in the plant: a 380V or 220V three-phase supply at 50Hz or 60Hz, enough transformer headroom, correctly sized incoming feeders and distribution boards, and cable routes that can carry the current without excessive voltage drop. A factory with spare transformer capacity can often plan this route early, while a factory near its limit has to decide whether an upgrade fits the project timeline.
Steam heating moves the heat source out of the machine and into a boiler house. Steam travels through an insulated pipe network, enters a jacket around the melting pot or holding tank, and condenses against the vessel wall. That condensation releases a large amount of heat, which passes into the syrup. The jacket temperature follows the steam pressure, so a pressure setting on a reducing valve becomes a temperature setting on the vessel. This is why the published installed power for steam variants sits lower, between 35 KW and 180 KW: that electrical figure mainly covers pumps, motors, controls and auxiliary equipment, while the thermal energy itself arrives through the steam main. Steam consumption depends on the heat load the process demands, not on the installed electrical figure, and the melting stage needs far more steam than the holding stage because it has to raise material from cold. For the factory, steam heating adds a second utility system to maintain. A boiler, water treatment, pressure control, steam traps and condensate return all become part of the daily routine, and the steam main has to be insulated and kept free of leaks. In return, heat arrives at the vessel through a jacket that can be built into the melting pot and the holding tank without changing the electrical infrastructure of the workshop. Holding becomes a matter of keeping the jacket supplied at the right pressure, which suits plants where syrup stays in the tank for extended periods between depositing runs.
The practical choice usually follows the utilities a factory already has and can keep running reliably. A candy plant with an existing boiler and spare steam capacity can connect steam heating to the pipe network it already operates, provided steam pressure stays steady. Pressure swings translate directly into jacket temperature swings, and that shows up in syrup viscosity and depositing behaviour. A plant with no boiler, but with spare transformer capacity and a manageable electricity supply, can take the electric route and keep the heating system inside the production hall. Control logic differs in step with the heat source. Electric heating responds quickly because the controller acts on power delivered right at the vessel, which suits line configurations where melting and holding shift between stages several times per shift. Steam control acts through valves and pressure, so heat input changes more gradually and the system carries more thermal inertia. In both cases, modular batch control concepts such as those described in ISA88 help engineers define melting, holding and transfer as separate stages with their own setpoints, interlocks and completion conditions, whether the energy comes from a cable or a pipe. Maintenance skills also shape the outcome. Steam systems need boiler operation, water treatment, trap inspection and pipe insulation care, while electric systems need attention on heating elements, contactors, terminals and cabinet cooling. Whichever way a plant goes, the melting and holding stage only performs as well as the utility behind it, and the installed power figure published for each variant should be read together with the utility it assumes.
Electric heating and steam heating differ first in where heat is produced: inside the machine or in a boiler house. That difference explains the published installed power ranges of 60 KW to 280 KW for electric variants and 35 KW to 180 KW for steam variants, and it explains why the two numbers are not directly comparable. Neither method wins in every factory. The useful questions are about transformer headroom, steam supply stability, control requirements, and who on site can maintain the system day after day. A published specification for a jelly candy production line is a starting point for that conversation, not the answer by itself.
A：The main difference is where the heat comes from. Electric heating converts electrical power into heat at the melting pot and holding tank, so the machine owns the heat source and responds quickly to temperature changes. Steam heating takes heat from a boiler, sends it through pipes into jackets around the vessels, and adjusts jacket temperature by controlling steam pressure. Both approaches melt and hold syrup, but they depend on different factory infrastructure and different control hardware.
A：The published ranges reflect what the electrical supply has to cover. Electric heating variants carry the full thermal load, which is why they start around 60 KW and reach 280 KW across the model range. Steam heating variants list 35 KW to 180 KW because their electricity mainly drives pumps, motors, controls and auxiliary equipment, while the thermal energy comes from the steam main. Steam consumption follows the heat load instead, so the installed electrical figure is not a running-load comparison.
A：A plant with a boiler and dependable steam pressure can usually connect steam heating to its existing network, keeping in mind that pressure stability directly affects jacket temperature. A plant without steam but with spare transformer capacity and a manageable electricity supply can plan around electric heating and keep heat generation inside the production hall. Boiler operation, water treatment and steam trap care on one side, and electrical maintenance on the other, often decide which route a factory can run comfortably.
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