Blog
Sep. 04, 2026
When a beverage contains boba, nata de coco, aloe vera, fruit pulp, or diced fruit, a standard liquid filler may produce uneven portions, blocked nozzles, or poorly sealed cups. A correctly selected beverage cup filling and sealing machine solves these problems by separating particle dosing from liquid filling and controlling each portion with repeatable settings. This guide explains how to use a bubble tea filling machine, fruit piece beverage filling machine, or dessert cup sealing machine for accurate production. The key technical factors are dosing accuracy, particle suspension, and volumetric filling, supported by a suitable pump, agitator, and sealing system.
Many beverage businesses begin with a liquid-only filler and add inclusions later. That approach often creates inconsistent cups because pearls settle quickly, fruit pieces bridge inside the hopper, and high-viscosity syrup flows differently from water. A cup may contain 18 g of boba in one cycle and 28 g in the next, even when the machine display shows the same setting.
The main production problems are:
For this reason, a reliable packaging machine for desserts and beverage products should be configured around the recipe rather than selected only by advertised speed. A machine that fills 1,200 liquid cups per hour may not achieve the same output with 10 mm tapioca pearls or 15 mm fruit cubes.
Record the recipe before adjusting the machine. The following information is essential:
| Parameter | What to Record | Why It Matters |
|---|---|---|
| Liquid volume | For example, 350 mL per cup | Determines pump stroke or filling time |
| Inclusion weight | For example, 25 g of pearls | Determines particle dosing settings |
| Particle size | For example, 6–10 mm diameter | Determines hopper outlet and nozzle clearance |
| Viscosity | Measure at the actual filling temperature | Influences pump pressure and flow rate |
| Temperature | For example, 4–8°C for chilled drinks | Changes viscosity and product safety |
| Target tolerance | For example, ±2 g per cup | Defines the acceptance standard |
Do not calibrate a machine with water and assume that the result will remain accurate with syrup, milk tea, or fruit pulp. Water has a viscosity close to 1 mPa·s at room temperature, while many milk tea and fruit preparations are substantially thicker. The actual product must be used during the final calibration.
Ingredient preparation has a direct effect on filling accuracy. Cooked tapioca pearls should be drained consistently and held in syrup according to the product specification. Excess cooking water can dilute the syrup and change particle buoyancy. Fruit pieces should be cut within a controlled size range, such as 8–12 mm, rather than mixed with large irregular pieces.
Before loading the machine:
Prepare the following equipment:
Inspect the product-contact surfaces for residue, cracks, loose fittings, or sharp edges. A clean-in-place, or CIP, routine should be defined for the liquid path. Particle hoppers often require manual removal of larger pieces because a liquid-only CIP cycle may not flush them completely.
Check that the cup diameter, height, flange width, and material match the machine mold. A cup that is too short may not sit securely under the filling nozzle. A narrow flange can reduce the sealing area and increase leak risk.
Use sealing film designed for the cup material. For example, PP cups generally require a compatible heat-seal film with an appropriate sealing temperature and dwell time. Do not increase temperature simply to compensate for a dirty rim. Excessive heat can deform the cup or weaken the film.
Start with a low-speed trial and set the target inclusion weight. If the target is 25 g, collect at least 10 individual particle doses and weigh each one. Calculate the average and range:
Average dose = total sample weight ÷ number of samples
Weight range = maximum dose − minimum dose
For a 25 g target, a practical initial acceptance range may be 23–27 g, depending on the product specification. If the sample weights are 24.1, 24.8, 25.0, 25.4, and 26.2 g, the average is 25.1 g and the range is 2.1 g. Adjust the gate opening, cup volume, or servo stroke if the average is consistently high or low.
Do not fill the hopper to its maximum capacity during the first calibration. A very deep product column increases pressure on the outlet and may change the particle flow. Begin with approximately 30–50% hopper capacity, then test again at the normal operating level.
For pulp or small fruit particles suspended in liquid, use a slow agitator or recirculation system. The goal is to prevent settling without introducing excessive air. Excessive agitation may break fruit pieces, increase foam, and cause unstable filling.
A useful starting point is a low agitator speed with a short mixing interval, followed by a 5–10 minute observation period. If particles settle visibly during that time, increase agitation gradually. If the drink becomes foamy or fruit pieces fracture, reduce the speed or change the impeller design.
For boba and larger inclusions, avoid relying on liquid recirculation alone. Tapioca pearls can damage soft tubing and may not travel reliably through a narrow liquid pump. A separate particle dosing mechanism is usually more stable.
Fill the liquid after the inclusion dose if the product design allows it. This sequence can reduce splashback and help move small particles into the cup. For a 350 mL cup with a 25 g pearl dose, the liquid volume may need to be reduced so that the total fill level remains below the sealing flange.
Use the actual beverage to calibrate the liquid filler:
For a 300 mL liquid target with a ±1.5% tolerance, the acceptable range is 295.5–304.5 mL. The correct tolerance depends on the product label, local regulations, and the company’s quality standard.
The nozzle should be close enough to reduce splashing but high enough to avoid contact with particles in the cup. A useful starting clearance is approximately 10–20 mm above the product surface, followed by testing.
The nozzle opening must exceed the largest particle dimension with sufficient clearance. If the largest fruit cube is 12 mm, a 12 mm internal passage is not necessarily adequate because irregular edges can create a bridge. A larger, smooth-bore nozzle may be required.
For products containing soft pulp, use a nozzle and valve design that reduces dead zones. Dead zones allow pulp to accumulate and later fall into the cup as an uncontrolled lump.
The cup must stop completely before dosing begins. If the indexing motion continues during filling, the stream may strike the sidewall and contaminate the sealing rim. Check the following timing sequence:
Use the shortest stable filling time rather than the fastest possible setting. A cycle that is 0.2 seconds faster but produces 5% more splash may reduce total output because operators must reject or clean cups.
Accurate filling is not complete until the cup is sealed without leaks. Set the sealing temperature, pressure, and dwell time according to the cup and film supplier’s recommendations. Then verify the settings with a practical test.
Inspect at least 20 consecutive cups for:
If pulp contaminates the flange, adjust the fill height, nozzle position, or anti-drip function before increasing sealing pressure. Pressure cannot reliably correct a contaminated sealing surface.
At startup, collect 10–30 cups at regular intervals. Record particle weight, liquid weight, total net weight, seal appearance, and product temperature. A simple control chart can show whether the process is drifting.
For example, if the target net weight is 325 g and the first samples are 324.8, 325.6, 326.1, 324.9, and 325.2 g, the process is close to target. If later samples rise to 329–331 g, inspect hopper level, pump calibration, and product temperature rather than changing settings randomly.
During a commissioning run for a small milk-tea operator, the first five test cups were intended to contain 25 g of tapioca pearls and 300 mL of milk tea. The recorded pearl weights ranged from 19.6 to 31.4 g. The operator initially suspected the scale, but the actual issue was that the pearls were settling against one side of the hopper outlet.
The adjustment included three changes:
After adjustment, a 20-cup test produced pearl doses between 23.8 and 26.1 g, with an average of 25.0 g. The milk tea volume also became more stable after calibration at the actual chilled temperature rather than with room-temperature water. The operator reported fewer rim-cleaning stops during the next production session, although the final acceptance still depended on the company’s own quality records.
This case demonstrates why a boba cup filling machine must be tested with the real particle size, syrup condition, temperature, and hopper level. The machine setting alone cannot overcome inconsistent ingredient preparation.
A narrow liquid pump may crush fruit, create blockages, or deliver an intermittent dose. Use a separate particle dosing system or a wide-passage sanitary pump designed for solids. Confirm the maximum particle size specified by the equipment manufacturer.
Foam, pulp, and syrup can spread onto the sealing flange when the cup is overfilled. Reduce the liquid volume, lower the nozzle splash, or increase the headspace. The required headspace depends on cup geometry and transport conditions, but the product should remain below the sealing area after normal handling.
Milk tea, syrup, and fruit preparations often become more viscous as they cool. If calibration is performed at 25°C but production runs at 6°C, the pump may require a longer stroke time or different pressure. Measure and record temperature during calibration and production.
High agitation can introduce air, increase foam, and damage delicate fruit. Reduce agitator speed, use a gentler impeller, or apply intermittent mixing. The product should remain evenly distributed without visible foam growth.
Sticky pearls may adhere to stainless steel surfaces when exposed to air. Keep the holding syrup at the specified concentration, maintain a controlled product level, and clean the hopper before residue hardens.
Detergent residue, rinse water, or loosened gasket material can affect the sealing surface after sanitation. Dry and inspect all components before restarting. Run several empty cup cycles or test cups before releasing the first commercial batch.
Rated speed is usually measured under ideal conditions with a simple liquid and standard cup. For drinks with inclusions, use the actual tested rate. If a machine produces 900 acceptable cups per hour with 25 g of pearls and a 300 mL liquid fill, that figure is more useful than a higher liquid-only rating.
Products containing milk, fruit, sugar, and starch can support microbial growth if residues remain in the liquid path. Follow the food safety plan, validated chemical concentration, contact time, rinse procedure, and local regulations.
A practical cleaning sequence includes:
Do not assume that a machine is clean because the exterior looks clean. The most difficult areas are usually valve seats, gasket grooves, hopper outlets, and tubing connections.
When comparing Yijianuo or another equipment supplier, ask for a product-specific test rather than relying only on catalog speed. Provide the supplier with your actual cup, film, beverage, inclusion size, target weight, and production temperature.
Important questions include:
Request a written acceptance test. It should define the cup format, product temperature, target liquid volume, inclusion weight, acceptable variation, sealing performance, and tested output. This prevents disagreement between the advertised specification and the real production result.
Accurate filling of pulp, pearls, and fruit pieces depends on controlling the entire process: ingredient size, drainage, temperature, hopper level, dosing mechanism, nozzle clearance, liquid volume, cup indexing, and seal cleanliness. The most reliable workflow is to dose large inclusions separately, use a calibrated volumetric filler for the liquid, maintain gentle suspension for pulp, and validate the result with repeated weight checks.
For a production-ready packaging machine for desserts and beverage products, select equipment based on the real recipe and run a documented trial before purchase. In practical terms, record the results of the bubble tea filling machine, fruit piece beverage filling machine, or dessert cup sealing machine at the actual temperature and speed. Monitor dosing accuracy, particle suspension, and volumetric filling, then verify the CIP routine, anti-drip valve, and heat-sealing parameters. These measurements provide a more dependable basis for choosing Yijianuo equipment than a general speed claim.
Yes, some systems combine a particle dosing unit with a liquid filling unit and cup sealer. However, the particle hopper, outlet, valve, and nozzle must be compatible with the size, stickiness, and softness of the boba. A liquid-only filler is not automatically suitable for pearls.
Both sequences are possible. Adding pearls first can reduce splash and help place them at the bottom of the cup. Adding liquid first may be useful for certain layered products. Test both methods and select the sequence that provides the most consistent weight and cleanest sealing rim.
Accuracy depends on the product, cup, pump, inclusion size, and operating speed. A supplier should provide measured results from your actual product. For many controlled liquid applications, a target around ±1–2% may be achievable, while particle portions often require a separate tolerance because irregular shape and density create additional variation.
Pulp settles when the particle density, viscosity, and agitation level are not balanced. Increase gentle agitation gradually, shorten the time between mixing and filling, or adjust the formulation if permitted. Avoid aggressive mixing that creates foam or damages the pulp.
There is no universal size. The nozzle passage must be larger than the largest particle and should provide clearance for irregular edges. Measure the largest piece in the batch and confirm the recommended passage with the machine supplier. Oversized fruit pieces should be screened or cut before filling.
Check the fill height, nozzle position, valve shutoff, anti-drip delay, and cup indexing. Also inspect for foam and excessive agitation. Cleaning the sealing flange before every cup is not a production solution; the filling process should be adjusted to keep the rim clean.
Usually not. Temperature changes viscosity, flow rate, foam behavior, and sealing conditions. Create separate recipes for hot and chilled products, and calibrate each recipe using the actual beverage temperature.
Recalibrate at startup, after changing the cup or recipe, after maintenance on the pump or valve, and whenever sample weights drift outside the control limit. High-volume operations may also schedule calibration at fixed intervals, such as once per shift or once per production day.
