Liquid Sucked into the Sealer Machine Causing Malfunctions? 5 Practical Tips to Prevent "Liquid Invasion" from the Source

Liquid Sucked into the Sealer Machine Causing Malfunctions? 5 Practical Tips to Prevent "Liquid Invasion" from the Source

Many people encounter situations where "liquid is sucked into the vacuum pump of a sealer vacuum packaging machine, causing the sealer vacuum packaging machine to make abnormal noises, shut down, or even be damaged" when sealing soup-containing cooked food, sauces, or fresh fruits and vegetables. This not only emulsifies the vacuum pump oil and shorts the motor but also may lead to subsequent sealing failure—a major issue for both home users and commercial operators relying on food vacuum packaging for freshness. In fact, as long as you take proper precautions in the three links of "pre-treatment, operation, and vacuum sealer accessory adaptation", you can completely avoid the problem of liquid invasion.

I. Pre-treatment: First "Shape" the Liquid to Cut Off the Suction Path

The core reason why liquid is sucked into the heat sealer machine is its strong fluidity—it easily flows toward the suction port along with the air flow during vacuuming. Making the liquid "lose its fluidity" through pre-treatment is the most fundamental way to avoid this, especially critical for sealing high-moisture foods that rely on vacuum packaging for food preservation.

1. Freezing and Shaping: Turn Liquid into "Solid" to Fear No Suction

When sealing food with soup (such as braised pork, spiced meat, homemade sauces), first put the food together with the soup into the refrigerator for freezing. Wait until the soup is completely solidified (usually frozen at -18°C for 2-4 hours, depending on the amount of soup) before taking it out for sealing with a household vacuum sealer or commercial vacuum packaging machine. The solidified soup will not flow and will only stick to the food during vacuuming, without being sucked into the vacuum pump at all.

Practical Details:

When freezing, use shallow containers for separate packaging, and control the thickness of the soup layer to 1-2 cm to speed up solidification—ideal for matching small-sized vacuum sealer bags;

There is no need to fully thaw after taking it out—sealing when there is slight frost is optimal to prevent the soup from flowing again after thawing, which is key to maintaining vacuum tightness;

When sealing pure liquids such as sauces and fruit juices, they can be frozen into ice cubes first before being put into food-grade vacuum bags, completely eliminating the risk of suction and ensuring compliance with food safety standards for packaging.

2. Draining/Absorbing: Reduce Free Liquid on the Surface of Ingredients

When sealing fresh fruits and vegetables (such as washed strawberries, blueberries) or fresh meat with blood—foods where excess moisture can ruin vacuum sealing results—first remove the excess liquid on the surface:

Gently press the fruits and vegetables with kitchen paper to absorb the surface moisture and prevent water droplets from hanging on the skin, which could otherwise seep into the vacuum sealer’s mechanism;

Wrap the fresh meat with kitchen paper for 10-15 minutes to absorb the blood, especially paying attention to the accumulated liquid in joints and gaps—this avoids contaminating the sealing strip of the vacuum sealer;

For cooked food with soup, you can first drain the soup (store the soup separately in a vacuum container) or spread oil-absorbing paper on the surface of the food to absorb excess oil and soup before sealing with heavy-duty vacuum bags (suitable for oily foods).

II. Operation Skills: Adjust the Sealing Method to "Set a Defense Line" for Liquid

Even if there is a small amount of liquid on the surface of the ingredients, you can avoid the liquid being sucked into the heat sealer machine by adjusting the operation method. The core is to "change the flow direction of the liquid" and "shorten the distance from the liquid to the suction port", which applies to both external thermal sealer machine and internal thermal sealer machine—the two main types of vacuum packaging equipment.

1. Tilted Placement: Keep Liquid "Away" from the Suction Port

Whether using an internal vacuum sealer (common for home use) or an external vacuum sealer (preferred for large or irregularly shaped items), you can guide the liquid away from the suction area by adjusting the tilt angle during sealing:

Internal vacuum sealer: Place the vacuum bag containing the liquid ingredients at a 45° tilt, so that the liquid concentrates at the bottom of the bag (away from the suction port near the sealing strip). When vacuuming starts, the air flow is sucked out from the top, and the liquid stays at the bottom due to gravity without being sucked in;

External vacuum sealer: When inserting the vacuum nozzle into the vacuum sealed bag, place the nozzle in the upper half of the bag, and let the liquid settle at the bottom. The air flow is sucked from the upper part during vacuuming, avoiding direct contact between the nozzle and the liquid—critical for preventing clogs in external vacuum sealer hoses.

Key Reminder: The total amount of ingredients and liquid in the vacuum sealer bag should not exceed 2/3 of the bag's capacity. Reserve enough space for the liquid to "settle" to prevent overflow, which could damage the vacuum sealer’s heating element (used for sealing).

2. Step-by-Step Vacuuming: Reduce Air Flow "Suction" to Avoid Liquid Splashing

Many modern bag sealer machines (both home and commercial models) support the "step-by-step vacuuming" or "manual speed control" function—features designed to handle delicate or high-moisture foods without ruining vacuum packaging. When sealing liquid, use the low-speed and step-by-step mode to prevent the strong air flow from "sucking up" the liquid:

For the first vacuuming cycle, stop when the bag is half-tight (about 50% vacuum degree) and pause for 10 seconds to allow the liquid to settle due to inertia—this prevents the formation of a "liquid vortex" near the suction port;

For the second cycle, continue vacuuming until full vacuum tightness is achieved. The slow air flow will not disturb the liquid, ensuring it stays away from the vacuum pump;

For older household vacuum sealers without the step-by-step function, manually control the vacuum button—press and release it repeatedly to replace continuous strong suction with "intermittent vacuuming", a simple workaround to protect the bag sealer machine.

3. Sealing First: Seal the Edge First Then Vacuum to "Mark a Forbidden Zone" for Liquid

For external vacuum sealers or commercial vacuum packaging machines with customizable programs (such as those used in delis or meal prep businesses), you can adjust the sequence to "seal first, then vacuum" (the default setting is usually "vacuum first, then seal")—a professional technique to secure liquid-containing foods:

First, use the machine’s heat-sealing function to seal a 1-2 cm area at the opening of the vacuum bag, forming a "sealed edge" that confines the liquid below the edge—this acts as a physical barrier against liquid flow;

Then insert the external vacuum nozzle from a small "temporary opening" above the sealed edge for vacuuming; once the desired vacuum degree is reached, use the heat sealer again to close the temporary opening;

This method is widely used in commercial food vacuum packaging (e.g., for ready-to-eat soups or sauces) because it eliminates the risk of liquid entering the bag heat sealer machine entirely, even with high-moisture products.

III. Tool Adaptation: Choose the Right Auxiliary Tools to Improve Protection Level

For users who frequently seal liquid-containing foods (such as home bakers making sauces or restaurants packaging takeout meals), matching the vacuum sealer with specialized tools can further reduce risks and enhance vacuum packaging efficiency. These tools are designed to complement vacuum sealers and ensure long-term machine durability.

1. Use Leak-Proof Vacuum Bags: Equipped with a "Liquid Barrier Layer"

Not all vacuum sealer bags are the same—choose leak-proof vacuum bags (labeled as such by manufacturers) for liquid-containing foods. These bags have additional anti-slip patterns or PE coatings at the sealing edge, which enhance the barrier property against liquids and improve vacuum retention:

The anti-slip patterns on the inner side of the bag mouth slow down the flow of liquid toward the suction port; when combined with tilted placement, the protection effect is doubled, making them ideal for soup vacuum packaging;

Some leak-proof vacuum bags have a "self-standing design" at the bottom—they can be placed upright during sealing, so liquid concentrates at the bottom and never touches the sealing area or the vacuum sealer itself;

Avoid using thin, generic vacuum bags (thickness < 12 filaments) for liquids—these bags are prone to deformation under the weight of liquid, leading to overflow and potential damage to the vacuum sealer’s internal components. Instead, opt for 18-20 filament vacuum bags (heavy-duty) for liquid applications.

2. Install Liquid-Proof Accessories: "Install a Filter" for the food sealer machines

Many food sealer machines brands offer optional liquid-proof accessories that can be retrofitted to existing machines, adding a "secondary defense" against liquid invasion. These accessories are affordable and easy to install, making them a smart investment for frequent users:

Liquid filter cup: Installed on the vacuum pipeline between the suction port and the vacuum pump, this cup catches any liquid that is accidentally sucked in. The liquid collects in the cup (instead of entering the pump) and can be poured out regularly—essential for oil-type vacuum pumps that are sensitive to liquid contamination;

Anti-suck-back valve: A one-way valve that attaches to the suction port of household vacuum sealers. It allows air to flow from the vacuum bag into the pump but blocks liquid from being sucked back into the machine when it shuts down—a common issue that causes vacuum pump oil emulsification;

For temporary solutions (e.g., when accessories are unavailable), cover the suction port with a clean medical gauze bag. While less effective than dedicated filters, it can trap small amounts of liquid and prevent them from reaching the vacuum pump—a quick fix for emergency use.

IV. Emergency Treatment: If Liquid Has Been Sucked In, Reduce Damage in This Way

Even with precautions, accidents can happen—if liquid is accidentally sucked into the vacuum sealer, immediately follow these steps to minimize damage and avoid costly repairs (especially for commercial vacuum packaging machines that are critical to business operations):

1. Power Off and Stop the Food Sealer Machines: Unplug the power cord immediately to prevent the liquid from contacting the motor or electrical components, which could cause a short circuit and permanent damage to the vacuum sealer;

2. Pour Out the Liquid: For internal vacuum sealers, open the vacuum chamber and tilt the machine to pour out residual liquid; for external vacuum sealers, disconnect the vacuum hose and nozzle, then drain any liquid trapped in the tubing—use a dry cloth to wipe the chamber and hose thoroughly;

3. Drying Treatment: Wipe the sealing strip, suction port, and internal surfaces with a dry cloth, then place silica gel desiccants inside the vacuum chamber (or hose) and let the machine stand for 24 hours. This ensures all moisture is absorbed, which is crucial for preventing sealing strip degradation and vacuum pump corrosion;

4. Check the Vacuum Pump: If liquid is sucked into an oil-type vacuum pump (common in commercial models), drain all the old vacuum pump oil—it will be emulsified and milky in appearance, losing its lubricating and sealing properties. Refill with fresh, manufacturer-recommended vacuum pump oil; for dry vacuum pumps (used in some household models), contact after-sales service for inspection, as liquid can damage their rotor systems.

Liquid being sucked into the vacuum sealer during vacuuming seems to be an "operation error", but in fact, it is often due to a mismatch between the machine’s settings, the vacuum packaging materials used, and the type of food being sealed. By understanding the unique needs of liquid-containing foods and leveraging vacuum sealer best practices—such as using leak-proof vacuum bags, adjusting vacuuming speed, and installing liquid-proof accessories—you can protect your machine, ensure consistent vacuum tightness, and extend the shelf life of your food. Whether you’re a home user sealing homemade soups or a business owner relying on commercial food vacuum packaging, these tips will help you achieve reliable, trouble-free results.