Key Challenges of High-Viscosity Sauce Filling and Corresponding Solutions
Introduction:
In the modern food processing industry, high-viscosity sauces are difficult to handle. Their filling is very challenging, as these products have resistance to flow due to friction that affects almost every step of the filling process. Consumer demand for high-viscosity sauce is increasing worldwide, so it's important that these sauces are filled accurately, efficiently, and hygienically. The food processing industry is under high pressure to keep the quality of products the same while improving efficiency.
In the food processing industry, if the liquid filling machine used for low-viscosity fluids is used for high-viscosity liquids, the result would not be the same but disappointing. The liquid will flow slowly, trap air pockets, have inconsistent fill levels, and frequently drip from the filling nozzle. To handle these issues, modern industries that supply liquid filling solutions such as SKY MACHINES provide advanced solutions to the beverage industry. These engineered solutions deal with viscosity as an obstacle. They manage this high viscosity with optimized fluid handling, precision motion control, hygienic construction, and robust mechanical design.
In this article, we will learn about the challenges of high-viscosity sauce filling and how to solve these challenges with engineering solutions.
1. Flow Resistance
Liquids like water and other thin liquids flow fast in pipes and nozzles, having turbulent flow and mixing while flowing through the system. But for viscous liquids, internal resistance makes them flow slowly through pipes with little or no mixing, and flow changes from turbulent to laminar as viscosity increases. Laminar flow has greater friction between the pipes and fluid, making it necessary to have a mechanical force to move it efficiently through the pipe.
When handling high-viscosity liquid, torque is more important than speed. It means if you have a motor operating at high speed, you are not going to have better flow, but it will introduce air into the liquid. So to have high torque, you need to have a motor that operates at slow speed and high torque that enables the pump to push the liquid smoothly with no excessive stress on the liquid-filling system.
Another solution is the use of a positive displacement pump that traps a fixed quantity of liquid and pushes it to the filling system. Piston fillers, gear pumps, and lobe pumps. All these can be used to have better results and consistent volumetric output.
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2. Air Entrapment and the "Compressibility" Trap
Air trapped inside the viscous liquid is difficult to handle, as thick liquids do not allow the air to move to the surface easily. This air trapped inside the liquid can cause inaccuracy in the filling process. If 2 containers are filled and one has trapped air inside, both will look completely filled, but the one that has air bubbles shows false levels. It also affects product appearance.
During filling, trapped air creates additional challenges for liquid-filling machine suppliers. Air is compressible, and it will compress during filling, appear to occupy less volume, and decompress after filling is completed. This makes consistent weight filling with accuracy very difficult.
Liquid filling suppliers use vacuum mixing and deaeration systems to resolve this issue, making the liquid more consistent in density.
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3. "Messy" Finish: Stringing, Dripping, and Seal Integrity
Viscous liquids can have a messy finish even when the filling volume is perfect. Thick liquids behave very differently from the thinner liquids. They can drip, string, or remain on the container and look ugly, cheap, and unhygienic.
At the last moment, when filling is going to be completed, the viscous liquids, instead of breaking cleanly, start to stretch in a phenomenon called "stringing." The product will remain on the neck, rim, sealing surface, or cap. This leads to contamination risk and damage to labels, making your product look poor.
This problem is solved by liquid-filling machine suppliers with suck-back technology, where filling nozzles suck back or retract small amounts of product at the end of filling. This will help break the liquid stream and avoid dripping. Positive shutoff nozzles are another method where a mechanical device is used to break the product flow.
Liquid filling suppliers also use bottom-up filling, where nozzles start filling near the bottom and move up as the liquid level rises.
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4. Thermal Management: Stabilizing Viscosity for Consistency
As a user, think of a cold morning and try to pour out a sauce from a bottle. The flow will be slow if you compare it with the flow of sauce at a warmer temperature. It means temperature has a big effect on flow due to changes in viscosity. At low temperatures, many beverages become viscous, adding impact to pumping, transportation, and filling performance.
During the filling process, if a liquid is thinner at the beginning and becomes viscous later due to temperature change, it can lead to inconsistent filling time, inaccurate filling, an increase in pump load, and reduced production efficiency. To deal with this problem and to have a constant-temperature beverage-filling machine, suppliers come up with the application of jacketed temperature control, where they use double-jacketed tanks and heated piping to maintain a stable temperature throughout the production process.
Tanks and pipes in a jacketed system are provided with a heating medium in a space surrounding the contact area of the product to transfer the heat to the liquid. The liquid filling machine manufacturers also provide insulating covers, thermal jackets, and shields to avoid heat loss.
As a buyer, before starting production, ask yourself, can your product maintain a stable viscosity from the tank to the product container?
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6. Particulate Handling:
Sauces are sometimes very difficult to handle in the beverage industry, as most of these have chunks of herbs, seeds, fruit pulp, vegetable pieces, fibers, or other particulates. These are used to increase the flavor, but they pose a threat of blockage to the filling system, causing flow inconsistency, damage to the product, and production interruptions.
The system designed for normal sauces without any solid particles can't be used for a sauce with particles because pipes, nozzles, valves, and all the components are prone to blockage due to insufficient clearances.
A beverage filling solution provider for this issue comes with a unique idea to have wide-bore infrastructure for all pipes, valves, and product passages. Sharp bends are avoided with no sudden change in the diameter of pipes. With this approach, smooth flow is achieved with reduced risk of blockage.
Since sauce is a viscous liquid, a pump has to be used for filling, and for sauce with solid particles, we need to use a pump that suits the particulates' characteristics and their size. Mostly lobe or screw pumps are used for sauce that has solid particles.
Cleaning-In-Place (CIP) systems are also provided to support the further removal of residue product and maintain a sanitation requirement as per food safety standards.
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7. Enhancing Precision with Servo-Driven Control
Many manufacturers provide servomotor control systems that help an operator adjust the speed and volume precisely according to parameters and the behavior of the liquid product. With this type of control, it becomes much easier to avoid overfilling, spills, and product waste.
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8. Maintenance and Longevity:
If you are handling a viscous liquid, especially with solid particles, it is very important to understand that maintaining filling equipment is difficult because some of the sauces are abrasive and possess greater maintenance demands on pumps, valves, seals, bearings, and other moving components. Regular inspection of the filling equipment is necessary to have an early diagnosis of the equipment. This approach will reduce downtime and increase production efficiency.
Cleaning-In-Place (CIP) systems are also provided to further support the removal of residue products and maintain a sanitation requirement as per food safety standards.
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Conclusion:
In this article, we have discussed all the necessary information regarding difficulties in handling viscous liquids like sauces, creams, pastes, syrups, etc. It's now very clear that conventional filling machines cannot handle viscous liquids. We have understood how to handle the problem of trapped air, temperature changes, particulates, dripping, and mechanical stress. In the modern era, most beverage filling machine providers, such as SKY MACHINES (www.sky-machine.com), have designed their equipment for durability, accessibility, effective cleaning, and efficient maintenance.
As an owner in the beverage industry, you have understood the challenges in your production line and selected the perfect machine that matches your requirements. You will have a reliable and efficient operation that provides you with sustainable growth and a long-term return on investment.
