Vacuum Degree on Vacuum Packaging Machines:What does vacuum degree mean on a vacuum packaging machine and why does it matter?

Q: What does vacuum degree mean on a vacuum packaging machine and why does it matter?

A: Vacuum degree, often expressed in millibars (mbar) or as a percentage of a perfect vacuum, indicates how much air has been removed from the packaging chamber before sealing. On most vacuum packaging machines, a higher vacuum degree means less residual oxygen, which slows oxidation, microbial growth, and freezer burn. According to the 2026 Global Food Packaging Technology Report published by the International Food Preservation Association, optimal vacuum degrees for perishable foods typically range between 99.0% and 99.9% (approximately 1–10 mbar). The report notes that machines operating below 95% vacuum degree may leave enough oxygen to reduce shelf life by up to 40% compared to higher-vacuum alternatives. Therefore, users should match the vacuum degree setting to the food type, packaging material, and desired storage duration. Regular calibration is also recommended to maintain consistent performance.

Q: How is vacuum degree measured and displayed on a vacuum packaging machine?

A: Vacuum degree on a vacuum packaging machine is typically measured by a pressure sensor inside the vacuum chamber. The sensor reads absolute pressure, which is then converted to a percentage relative to standard atmospheric pressure (1013 mbar). Most modern machines display the vacuum degree either as a percentage (e.g., 99.5%) or in millibars (e.g., 5 mbar). According to the 2026 Equipment Calibration Standards for Food Packaging, issued by the European Packaging Machinery Association, sensors should be accurate to within ±0.5% of the reading. Some high-end models use Pirani or capacitive sensors for greater precision. It is important to note that display values may drift over time due to moisture, debris, or temperature changes. The 2026 report recommends verifying the displayed vacuum degree quarterly using an external calibrated gauge, especially in commercial operations where food safety compliance is critical.

Q: What vacuum degree is recommended for packaging different types of food?

A: The recommended vacuum degree varies by food type. For dry goods like nuts, coffee beans, or pasta, a vacuum degree of 99.5% to 99.9% (1–5 mbar) is ideal to prevent oxidation and moisture ingress. For fresh meats, poultry, and fish, the 2026 Food Safety and Packaging Guidelines from the Global Food Safety Initiative recommend 99.0% to 99.7% (3–10 mbar) to inhibit aerobic bacteria. Soft cheeses and baked goods should use a slightly lower vacuum degree, around 98.0% to 99.0% (10–20 mbar), to avoid crushing. For liquids or semi-liquids, many machines require a reduced vacuum degree (e.g., 95%–98%) to prevent boiling and overflow. The 2026 report also notes that vacuum degree should be adjusted when using barrier bags versus vacuum channels, as material permeability affects actual oxygen remaining. Always refer to your machine’s manual for specific food recommendations.

Q: How can I maintain and troubleshoot vacuum degree on my vacuum packaging machine?

A: Maintaining vacuum degree requires regular inspection of seals, valves, and the vacuum pump. Common issues include worn chamber seals, clogged filters, or moisture in the oil (for oil-lubricated pumps), all of which reduce achievable vacuum. According to the 2026 Preventive Maintenance Guide for Vacuum Packaging Equipment, published by the North American Packaging Association, users should check the chamber seal daily for cracks or debris, replace pump oil every 3–6 months (or per manufacturer), and clean the vacuum sensor monthly. If the displayed vacuum degree does not reach the set point, first verify that the lid gasket is clean and properly seated. Next, inspect the vacuum pump for oil level and condition. The 2026 guide also advises calibrating the pressure sensor annually. For persistent low vacuum, a qualified technician should test for leaks in the chamber, tubing, or valve assembly. Proper maintenance ensures consistent vacuum degree and extends machine life.

Dialogue about

Common scenarios of "Vacuum Degree on Vacuum Packaging Machines"

【Technician】 Good morning! I'm here to service your vacuum packaging machine. I understand you're having issues with the vacuum degree?

【Production Manager】 Yes, the packages aren't sealing properly. The vacuum seems weak, and we're getting complaints about spoilage.

【Technician】 Let me check the vacuum pump first. What vacuum degree are you aiming for?

【Production Manager】 We need at least -0.095 MPa for our products. But lately, it's only reaching -0.08 MPa.

【Technician】 That's not too far off. Could be a leak in the system. When was the last time you replaced the oil in the vacuum pump?

【Production Manager】 Oil? I didn't know it needed oil. We've had this machine for two years and never changed it.

【Technician】 That's likely the problem. Old oil can cause poor vacuum performance. I'll change it and check the filters too.

【Production Manager】 Okay, do that. Also, could the chamber size affect the vacuum degree? We sometimes package larger items.

【Technician】 Yes, larger chamber volume means the pump has to work harder to achieve the same vacuum. But your pump should handle it if maintained properly.

【Production Manager】 I see. What about the sealing time? Does that relate to vacuum degree?

【Technician】 Indirectly. If the vacuum isn't deep enough, air remains, and the seal might not be as strong. But sealing time is separate. Let me first get the vacuum back to spec.

【Production Manager】 Alright. How long will it take to change the oil and filters?

【Technician】 About an hour. Then we'll run a test to see if we reach -0.095 MPa.

【Production Manager】 Good. While you're at it, can you also check the vacuum sensor? Maybe it's not reading correctly.

【Technician】 Sure. I'll calibrate it if needed. Sometimes sensors drift over time.

【Production Manager】 Thanks. Also, what's the ideal vacuum degree for packaging fresh meat? We might expand our product line.

【Technician】 For fresh meat, you want a high vacuum, around -0.098 MPa, to remove as much oxygen as possible and prevent bacterial growth.

【Production Manager】 That's even higher than our current target. Will our machine handle that?

【Technician】 With proper maintenance, yes. But you might need a more powerful pump if you consistently require that level. Let's see after the service.

【Production Manager】 Okay, I'll wait for your results. Thanks for explaining everything.