UHT Aseptic Filling Line

UHT Sterilizer and Aseptic Filling Lines for UHT Milk, Dairy and Liquid Food Processing Plants

A UHT sterilizer holds liquid food at sterilization temperature for a few seconds, and the aseptic filler behind it seals the product into packs sterilized inside the machine, so the pack ships and sells without refrigeration. Shengtu designs, integrates and commissions the complete line, from milk reception through to the filled and coded pack. Tell us the product, the capacity you need and the pack it goes into, and our engineering team builds the process route around them.

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Four inputs decide the shape of a UHT line: what you run, how acidic it is, how many liters per hour you need, and the pack it goes into. Those four fix the heating route, the holding time, the aseptic tank volume and the class of filler. Everything else on this page follows from them.
  • Written proposal within one business day
  • Complete line in 4–8 months from drawing approval
  • Aseptic tank and filler quoted inside the line scope
  • Witnessed acceptance test before shipment
Proposal turnaround Written proposal within one business day of your enquiry
Complete line delivery 4–8 months, counted from drawing approval
Order size We accept a minimum order of one set
Payment 40% deposit, balance before shipment
Before shipment Factory acceptance test to your checklist, on site or by live video
Company track record 2,000+ machines running in 52 countries, across all our food and beverage equipment
Layout of a complete UHT sterilization and aseptic filling line, from milk reception through to the filled pack.

UHT Sterilization Process: Indirect Heating and Direct Steam Injection

UHT processing involves two jobs, and shelf life depends on both. The sterilizer destroys the microorganism load in the product; the aseptic filler protects that sterilized product from the filling environment until the pack is sealed. Both halves have to hold, so we build and commission them together with the aseptic tank between them.

Indirect UHT heating: tubular and plate heat exchangers

Steam or hot water heats the product through a wall, so the heating medium never touches what you sell. A tubular heat exchanger runs longer between cleaning cycles on milk than a plate design, because there is no gasketed contact line for deposits to grow along.

  • Product-to-product regeneration recovers most of the heat, at a ratio set with your utility cost at design stage
  • Regeneration stays below 75 °C, sterilized side always at the higher pressure
  • Default route for white milk, cream-standardized products and lightly pulped juices
  • Holding tube dimensioned for about 4 seconds on standard white milk

Direct steam injection and steam infusion

Culinary steam is mixed into preheated product, which reaches 140–150 °C in a fraction of a second and is then flash-cooled in a vacuum vessel so the condensed water leaves again. That very short heat load protects color and nutritional value on sensitive products.

  • Product is lifted to about 80 °C in preheat, then to temperature by injection or infusion
  • Vacuum flash cooling removes the added water and drops the product toward filling
  • Injection runs longer between cleans; infusion gives tighter temperature control at higher cost
  • Aroma-sensitive recipes need the aroma added back aseptically after the vacuum vessel

Aseptic tank, filler interface and controls

Sterilizer and filler rarely run at matching speeds. An aseptic tank sits between them and absorbs the difference, sized against your filler’s changeover and stoppage pattern rather than the sterilizer alone.

  • Aseptic tank blanketed with sterile air, sized against your run pattern
  • Aseptic valve cluster, line sterilization, water run and pressure hold on a single control system
  • PLC and HMI with recipe management, batch records, alarm history and remote support
  • Interface to your chosen filler agreed at design stage, with signal list and interlocks

The seven stages of a UHT processing line

  1. Milk reception and chilled storage — raw milk is received, tested and held cold until the line calls for it.
  2. Preheating and deaeration — held at 90–95 °C, which is where heat-resistant enzymes are dealt with.
  3. Homogenization — fat globules are broken so cream does not separate over the shelf life; on direct lines this sits after sterilization and runs aseptically.
  4. Final heating — indirect heat exchangers or direct steam carry the product to 135–150 °C, by acidity and product.
  5. Holding tube — the product holds at temperature for the designed seconds in an unheated tube sloping upward at least 2.1 cm per meter, the geometry 21 C.F.R. 113.40(g) requires.
  6. Cooling — vacuum flash on direct lines, regenerative and chilled-water cooling on indirect lines.
  7. Aseptic tank and filling — sterilized product is buffered, then filled into packs sterilized inside the filler and sealed under sterile air.
Chilled raw milk storage
01

Chilled raw milk storage, where the enzyme load is largely decided.

Preheating section feeding the sterilizer
02

Preheating section feeding the sterilizer, held at 90–95 °C.

Homogenizer
03

Homogenizer sized against fat content and target shelf life.

Tubular UHT sterilizer
04

Tubular UHT sterilizer with holding tube, regeneration and cooling on one frame.

Reading a UHT process as B* and C*

B* measures the sterilizing effect a process delivers; C* measures the chemical damage it does on the way. A line is set to keep B* above 1 and C* below 1, which is where the product is safe and still tastes like the product.

  • B* = 1 is equivalent to 135 °C for 10.1 seconds, the same as F0 = 3
  • C* = 1 is equivalent to 135 °C for 30.5 seconds, or 140 °C for 21 seconds
  • Flow regime counts: below Reynolds 2,100 the delivered effect is halved against nominal holding time
  • Direct heating reaches the same B* at a lower C*, because heat-up and cool-down are nearly instantaneous

Where the sterilizing effect is actually accumulated

Plants set the holding tube and stop there, but the product keeps gaining sterilizing effect while it climbs to temperature and while it cools. A survey of 22 Australian UHT plants found the heat-up and cool-down sections carry 53% of the total sterilizing effect on indirect lines, against 17% on direct lines. Two lines with the same holding tube can therefore perform very differently in the incubation test.

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Products We Run: UHT Milk and Milk Products, Juices and Plant-Based Drinks

Dairy is the main line

White milk, flavored milk, cream, recombined milk and other dairy products are what most of these lines run, and the process grew up inside the dairy industry. The same product is written flavoured milk across most of our export markets, and it takes a slightly heavier heat load than white milk because of the added sugar and cocoa. Cream and high-fat drinks shift the homogenizer setting rather than the sterilizer setting, and when the raw milk supply is seasonal we size UHT milk production against the peak month rather than the yearly average.

Acidity decides the heating route before anything else does. Low-acid products above pH 4.6 need full sterilization at 135 °C and above, medium-acid products between pH 4.2 and 4.6 sit at 123–125 °C, and high-acid products below pH 4.2 are held at 90–95 °C because their own acidity finishes the job. Rows in the table below are ordered by that rule first, then by viscosity and by what the product carries.

Product family pH band Heating route What it changes on the line
White milk for ambient sale6.5–6.8Indirect tubular, 137–142 °C for about 4 sThe baseline every other product is measured against
Flavored milk and cocoa drinks6.3–6.8Indirect tubular, heavier heat loadSugar and cocoa raise fouling, so run length shortens
Cream and high-fat drinks6.4–6.7Indirect, two-stage homogenizationHomogenizer pressure and position, not temperature
Recombined and reconstituted milk6.5–6.8Indirect tubularHydration time upstream of the sterilizer
High-protein dairy drinks6.5–6.9Direct steam injection, 143–150 °C for 2–4 sShort heat load protects texture and color
Plant-based drinks: soy, oat, almond6.5–7.2Indirect or direct, by protein sensitivityStabilizer system and homogenization pressure
Coconut milk and coconut drinks6.1–6.9Indirect, wider tubesFat separation risk; tight homogenization needed
Clear fruit juices3.0–4.090–95 °C for 15–30 sLighter equipment and the lowest energy demand
Fruit juices with pulp3.2–4.290–95 °C for 15–30 s, wide tubesPulp pieces set the tube diameter and the pump
Nectars and juice blends3.5–4.290–95 °C for 15–30 sSugar dosing ahead of the sterilizer
Tomato products and sauces4.1–4.6123–125 °C for about 15 sViscosity sets the pump; verify each batch against pH 4.6
Fruit purees and pastes3.4–4.4123–125 °C for about 15 sWide tubes and low shear to protect the pieces
Ready-to-drink tea and coffee4.9–6.5Indirect, 135–140 °CColor and aroma retention drive the route
Soups and liquid meals with solidsAbove 4.6123–125 °C up to 135 °C, by piece sizeThe largest piece decides the hold, not the liquid
Liquid egg and egg-based drinksAbove 4.6Indirect, gentle temperature profileProtein denaturation caps the working temperature

Where viscosity and pieces change the route

In a holding tube the fastest layer of product decides the process, not the average. Viscous products and products carrying pieces flow unevenly, so tube diameter, pump type and hold are set so the fastest particle still receives the full treatment. Pieces also have to be heated through to their center, which is why a soup with vegetable cubes is a different machine class from a clear juice of equal throughput.

Your product is not on this list

This table covers what these lines run most often, not the limit of what they can run. Send us the product, its pH, its viscosity and the largest piece it carries, and we will tell you which heating route fits and where the risk sits.

  • Anything above pH 4.6 takes the full sterilization route, whatever the product is called — that route is what 21 C.F.R. 113 governs, thermally processed low-acid foods in hermetically sealed containers
  • Products carrying pieces are quoted against the largest piece, never against an average
  • Feeds needing washing, cutting or blanching first sit with our fruit and vegetable processing equipment
  • If the target product is dried rather than filled, the route is a fruit and vegetable dehydration line instead
Check your product in the UHT Line Selector
UHT Aseptic Filling Line Equipment

Aseptic Packaging Formats:
Cartons, Bottles, Pouches and Bag-in-Box

Inside the filler the pack is sterilized first, then filled and sealed in a chamber held under sterile air at positive pressure. How that sterilization is done depends on what the pack is made of, and the choice moves output and running cost more than the sterilizer does. Decide the format early: the aseptic filler is the largest single item in the line after the UHT system itself.

Format How the pack is sterilized Output band, published machine data What it suits
Aseptic carton, brick and gable Hydrogen peroxide at around 35%, then hot sterile air at about 210 °C Up to 12,000 packs per hour White milk, flavored milk and juice at volume
Aseptic carton, multi-size machine Same peroxide and hot air cycle, 500 ml to 1,000 ml on one machine Changeover under 15 minutes Plants running several pack sizes
Aseptic PET bottle Peroxide mist and hot air, or a peracetic acid rinse Up to 12,000 bottles per hour, 250 ml to 2 L Ready-to-drink dairy, tea and juice
Aseptic HDPE bottle Peroxide and hot sterile air Mid output band Regional dairy plants and school milk
Aseptic pouch and sachet Peroxide bath with film sterilization on the reel Up to 16,000 pouches per hour Lowest pack cost, 90 to 180 day shelf life
Bag-in-box and aseptic bag Radiation-sterilized bag with aseptic spout welding 5 L to 1,000 L Purees, concentrates, plant-to-plant supply
Aseptic drum and tote Radiation-sterilized liner in a rigid outer 200 L and above Fruit purees held for onward processing
Cup and bottle with foil lid Peroxide and hot air applied to the web Format dependent Dairy desserts and drinking products
Output figures in that column are the published ratings of machines in each class, taken from the filler suppliers concerned. Your line's output is set by the filler brand and model chosen in the proposal.

The buffer between the sterilizer and the packer

A filler stops for reel changes, seal checks and downstream jams, and the sterilizer cannot simply stop with it. An accumulator holding around 600 cartons absorbs roughly 7 to 8 minutes of downstream stoppage, and the aseptic tank holds the sterilized milk waiting behind it. Size those two together and the line stops re-sterilizing every time the packer coughs.

UHT Aseptic Filling Line System
  • Packaging material is qualified with the filler; the same board or film from a different supplier is validated again.
  • Container integrity is checked as a shift routine with seal and drop tests, not once at commissioning.
  • Three settings decide pack sterilization: hydrogen peroxide concentration, contact time and drying air temperature.
  • The sequence has a regulatory definition: 21 C.F.R. 113.3(a) sets aseptic processing and packaging as commercially sterilized product filled into presterilized containers, sealed with a presterilized closure, in an atmosphere free of microorganisms.

Carton systems from the major suppliers, Tetra Pak among them, work on the same peroxide and hot air principle, so a line designed around one format is not locked out of the others on the process side. If your pack decision is still open, we fix the process side first and hold the filler choice until your packaging supplier is settled.

UHT Sterilizer Specifications, Capacity Range and Process Parameters

Everything below is what the UHT production process itself requires. What differs between lines is the tube diameter, heating surface, pump class and control philosophy that deliver them. Your per-model specification sheet — capacity, heating surface, installed power, steam, water and air demand — is issued with the proposal, calculated against your product.

Parameter Value Why it sits there
Low-acid sterilization band 135–150 °C for 2–5 s Above pH 4.6 the spore load must be destroyed by heat alone
Medium-acid band 123–125 °C for about 15 s Acidity does part of the work, so the heat load drops
High-acid band 90–95 °C for 15–30 s Below pH 4.2 the product's own acidity holds the pack
Regulatory floor for ultra high temperature milk in the European Union Not less than 135 °C with a suitable holding time The wording of the EU definition; the holding time is set by your scheduled process
Sterilizing effect target B* above 1 One B* unit equals 135 °C for 10.1 s
Chemical damage ceiling C* below 1 One C* unit equals 140 °C for 21 s
Preheat holding 90–95 °C for 30–120 s Heat-resistant enzymes are inactivated here, not in the holding tube
Preheat holding for long-haul export Set case by case A longer preheat hold is reported to cut residual plasmin further (Machado et al. 2017, citing Stoeckel et al. 2016)
Holding tube design Sloped upward at least 2.1 cm per meter, no heating applied Every portion must receive the same hold
Temperature indication accuracy 0.5 °C against traceable calibration The recorded temperature is the legal record of the process
Regenerator pressure rule Sterilized side held above the unsterilized side Any leak is pushed outward, never inward
Heat regeneration Confirmed on your per-model specification sheet Recovered heat is the largest operating cost lever
Line sterilization before production Hot water at production temperature, at least 30 min once the temperature is reached The line is sterile before product enters it
Cleaning cycle 70–90 min Cleaning time is planned around run length, not the reverse
Commercial sterility confirmation 15 days at 30 °C or 7 days at 55 °C Incubation confirms the process; it does not control it
Lactulose index Measured against the limit your buyer sets A heat-damage marker used to compare lines
UHT Aseptic Filling Line Industrial Solution

What we need from you to fix these numbers

  • The product, its pH and the largest piece it carries
  • Target capacity in liters per hour, and hours per day
  • Packaging format, pack sizes and the filler you intend to run
  • Required shelf life and storage temperature in the destination market
  • Steam, electrical power, chilled water, cooling water and compressed air on site
  • A water quality report, which sets both the cleaning design and the cooling circuit
  • Floor area, ceiling height, and whether this is new construction or an existing hall
  • Destination country and the product registration route you have to follow there
SYS_REQ // WORKSHEET

Capacity and utilities worksheet

If you would rather gather the inputs before you talk to anyone, the worksheet walks through them in the order our engineers use. It produces exactly the list we would otherwise ask for on the first call.

Steam, power, water and air demand scale with capacity and heating route, not pack format

Bring the completed worksheet to the first call and the proposal comes back faster.

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Line Investment: UHT Milk Processing Plant Cost, Lead Time And Delivery Scope

A UHT line is priced as a scope, not as a machine. What moves the figure is how much of the line you buy from us, how automated it is, which heating route the product needs and what the filler has to do. So we fix the configuration first, and only then quote it.

Driver What changes Effect on the figure
Heating route Indirect tubular against direct steam injection or infusion Direct systems add a vacuum vessel, an aseptic homogenizer and more steam
Capacity Liters per hour, and hours per day Sets heating surface, pump class, tank volume and every utility connection
Scope of supply Single machine, process block, or complete line from milk reception to pack The largest single variable in any UHT quotation
Filler class and format Carton, PET bottle, pouch or bag-in-box The aseptic filler is the biggest item in the line after the sterilizer
Automation level Manual valve clusters against an automated valve matrix with batch records Changes both the plant equipment supplied and the commissioning time
Heat recovery Product-to-product regeneration against a simple cooling circuit; the recovery ratio is set on your per-model specification sheet Higher capital, lower running cost across the life of the line
What you order Lead time Counted from
Complete UHT sterilization and aseptic filling line 4–8 months Drawing approval
Single machine or single process module 30–45 days Drawing approval
Acceptance testing window at our workshop Scheduled Scheduled with you once the build plan is fixed

Payment runs on a 40% deposit with the balance before shipment, and a complete line is delivered in 4–8 months from drawing approval. Prices are quoted against one specific configuration, and the delivery basis is set in the proposal. Send us the configuration and you have a written proposal within one business day.

03

Aseptic Filling Against Hot Filling Over The Life Of The Line

Hot filling holds the product at 80–92 °C for around two minutes inside the pack, so the heat you just paid for is thrown away and the pack has to survive it. An aseptic line cools through regeneration instead and puts a large share of that heat back into the incoming product.

  • Hot-fill bottles carry vacuum panels and more material: published life cycle work puts a hot-fill PET bottle at 24 g against 16 g for the aseptic equivalent (Manfredi and Vignali, 2014, as cited in Food Engineering, 2023)
  • That is the real trade-off: the pack cost difference repeats on every pack, while the capital difference is paid once
  • Where the two curves cross depends on your volume, pack and energy price, so we model the crossover with your numbers rather than publishing one figure for everyone
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Commercial Sterility Assurance, Food Safety Validation and Factory Acceptance Testing

A UHT line is accepted on evidence, not on appearance. A process must be shown to deliver the sterilizing effect, a line must hold sterility for the whole run, and records must prove both afterwards. That chain is what we build, test and hand over.

How the line is checked before it leaves our floor

  • >
    Water run and pressure hold every circuit is run on water, pressure tested and leak checked, and the valve matrix is proven step by step.
  • >
    Line sterilization and hot run the line is sterilized with hot water at production temperature and held at your product's setting.
  • >
    Product trial to your parameters we run your product or the closest match we can source, at your holding time, and record the full profile.
  • >
    Acceptance testing to your checklist the factory acceptance test is witnessed on site or by live video against acceptance criteria for capacity, sterility and product quality agreed in advance, every point signed off.
  • >
    Document pack and packing records, drawings and certificates are signed off and packed with the line.
Pre-dispatch checks for UHT Aseptic Filling Line
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From Enquiry to Commissioning: The Six-Step UHT Processing Line Project Route

Most delay on a UHT project happens between the enquiry and the approved drawing, not in the workshop. The route below is deliberately front-loaded, so the slow decisions get made while nothing is being built yet. Delivery time is counted from drawing approval, not from the order date.

01

Enquiry and technical review

You send product, capacity, packaging format and site conditions, and we come back with a written proposal within one business day.

02

Process design and layout

Heating route, holding time, tank sizing, utility demand and a floor layout drawn against your actual hall.

03

Contract and drawing approval

Scope and schedule agreed with the 40% deposit, and the delivery clock starts when you approve the drawings.

04

Manufacturing

Fabrication, control panel build, assembly and internal inspection at one of our manufacturing bases.

05

Acceptance testing and trial run

Water run, line sterilization, product trial and sign-off against your checklist, on site or by live video.

06

Installation, commissioning and training

Our engineers commission the line and run it with your operators until your team runs it without us.

UHT Aseptic Filling Line Technical Route

UHT Line Selector Matrix

Route selection turns on acidity, protein sensitivity, what the product carries, and how long it must survive outside the cold chain. The matrix below is the shortcut our engineers use on the first call.

If you run Heating route Setting Why that route
White milk for ambient distribution Indirect tubular 137–142 °C for about 4 s Lowest cost per liter at volume, longest run length
High-protein or premium dairy drinks Direct steam injection 143–150 °C for 2–4 s Short heat load protects texture, color and extended shelf life
Fruit purees, sauces and tomato products Indirect, wide tube 123–125 °C for about 15 s Acidity lowers heat demand; viscosity sets the tube diameter
Clear and pulpy juices Indirect tubular or plate 90–95 °C for 15–30 s Below pH 4.2 the product largely holds itself
Anything sold inside 45 days with a cold chain in place Pasteurization or extended shelf life route 72–75 °C for 15 s, or 125–130 °C for 2–4 s with clean filling An aseptic line is over-specified for that shelf life

Where the regulatory clock sits in the schedule

In several markets the paperwork takes longer than the machine. Product registration, packaging material approval and process filing run on their own calendars, and none of them start faster because the line arrived early. We hand over the process data package at design stage so those applications run in parallel with manufacturing.

Who builds the line

We manufacture across four owned or self-built manufacturing bases, which keeps 80% of our main equipment categories inside our own workshops rather than behind a trading desk. What we do not build ourselves — a specific filler brand, an instrument your plant has standardized on — we buy, integrate and warrant inside the same scope. Either way the factory acceptance test is run on the assembled line at our floor.

Compare UHT, extended shelf life and hot filling

Installed Base Across Dairy and Beverage Plants, and Our Manufacturing Capability

The Shengtu engineering team has more than 10 years of experience in food and beverage processing equipment, and the company has 2,000+ machines running in 52 countries across its food and beverage equipment range. Customer names, plant photographs and reference visits are shared with written permission from the plant concerned, so ask and we will arrange whatever that plant allows.

Why dairy processors and beverage plants work with us

  • 4 owned and self-built manufacturing bases covering approx. 80% of our core equipment
  • Configuration adjustable to your raw material, capacity, process and budget
  • Upstream and downstream equipment available for complete lines
  • PLC, HMI, automation and IoT upgrades available on request
  • Export documents, packing, container loading and after-sales support
  • 10+ years of export and project experience
  • Exported to 52 countries with 2,000+ machines running
  • Video meetings and remote factory audits welcome

Manufacturing and engineering capability

  • Headquartered in Zhucheng, Shandong, with branches in Qingdao, Changzhou and Weifang
  • More than 20,000 m² of facilities across the four locations, including a 5,000 m² food machinery showroom
  • 7 patents and 100+ software copyrights
  • 100+ R&D projects
  • Management system certified to ISO 9001 and ISO 27001
UHT Aseptic Filling Line inside the food production facility
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UHT, ESL and Pasteurization: When a UHT Aseptic Line Is Not the Right Fit

Ambient distribution is what an aseptic line buys you. When the product never leaves the cold chain that capability costs you money the plant could have spent on capacity, so the rows below are the cases where we would point you somewhere else.

Raw milk carrying heat-resistant enzymes
The bacteria die at 72–75 °C, but the enzymes they left behind survive 135–145 °C for a few seconds and gel or embitter the milk months later
Fix it at milk reception and chilled storage; no sterilizer undoes an enzyme load already in the tank
Product sold inside 45 days with a cold chain already in place
You pay for ambient capability and then refrigerate the product anyway
An extended shelf life or pasteurization line at a fraction of the capital
High-acid product below pH 4.2 sold chilled
Full aseptic sterilization is heavier than the product needs
Hot filling at 80–92 °C, or in-line pasteurization with clean filling
Product sterilized after the pack is sealed
An aseptic filler cannot sterilize a rigid container that is already closed
A retort and autoclave sterilizer line
Recipe not adjusted for the heating route
Vacuum flash cooling on a direct line strips volatile aroma out of the product
Add aroma aseptically after the vacuum vessel, adjust viscosity, or dose above target
Preheat held at an intermediate 80 °C for 30 s
Proteolysis can rise rather than fall, because the enzyme is activated without being inactivated
Either hold at 90–95 °C long enough, or stop counting on the preheat section
Bacillus sporothermodurans present in the supply
Its spores survive 140 °C for 3.4–7.9 s, so a line rated to 140 °C cannot heat its way out
Treat it as market access, not food safety: control raw milk and workshop hygiene
Capital is fixed and a refurbished tier-one line is on the market
Nothing, on the day it lands. Cost moves to parts, and to finding people who still know that model years later
Buy refurbished where the model is common enough that parts stay easy to reach; buy new where you want one party answering for the whole line

Where you land on that list is decided mostly by the cold chain you can rely on, not by the product itself. In markets with thin cold-chain infrastructure a shelf-stable pack is the only way to reach the buyer at all, and an extended shelf life line is not a substitute. Moving up from extended shelf life to fully aseptic is a records step as much as a machinery step: for a low-acid product it means a scheduled process filed under 21 C.F.R. 113, on Form FDA 2541g, before production starts.

The most expensive mistake we see is a plant buying aseptic capability for a product that never leaves the cold chain. The second most expensive is buying it for milk whose enzyme load was already decided before the tanker reached the gate.

UHT Aseptic Filling Line

Engineering Tools: UHT Aseptic Filling Line

  • uht line selector

    Configure baseline technical parameters to determine the optimal thermal processing architecture for your specific liquid production requirements.

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  • capacity and utilities worksheet

    Calculate required facility utility allocations, including steam consumption, cooling water, and compressed air against target throughput.

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  • uht esl hot fill route check

    Systematically evaluate product routing feasibility and cross-contamination risks across UHT, ESL, and Hot Fill processing layouts.

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Frequently Asked Questions About UHT Sterilizers and Aseptic Filling Lines

Pasteurized milk is heated to 72–75 °C for 15 seconds, which kills the disease-causing organisms and most spoilage organisms, but the pasteurized product still needs a cold chain. Ultra-high temperature treatment works at a much higher temperature, 135 °C and above for a few seconds, and destroys the spores as well, so the sealed pack can be stored at room temperature.

Indirect tubular heating is the volume workhorse: lower utility demand, long runs between cleaning cycles, lowest cost per liter on white milk. Direct heating reaches temperature in a fraction of a second and cools under vacuum, which protects texture and color on high-protein products. Infusion controls temperature most precisely of the three, at the highest cost.

The holding tube is sized so the fastest-moving portion of product still receives the designed hold, which is why flow regime matters more than average velocity. Sterilizing effect also accumulates during heat-up and cool-down: a survey of 22 Australian UHT plants found that to be 53% of the total on indirect lines, against 17% on direct lines. That is why a process is specified as B* and C*.

Yes, with a wider tube, a gentler pump and a longer hold. The limit is not viscosity but the largest piece, because its center has to reach temperature while the liquid around it does not overcook. Products carrying pieces are quoted as their own machine class.

Your sterilizer decides whether the product is commercially sterile; the pack decides how long it stays that way. A carton with a full aluminium barrier holds ambient shelf life for months, a pouch 90 to 180 days, and clear PET without a barrier is shorter again because light and oxygen get through.

They are linked through an aseptic tank blanketed with sterile air, which absorbs the difference between a sterilizer that runs steadily and a filler that stops for reel changes. An accumulator of around 600 cartons covers roughly 7 to 8 minutes of stoppage before the tank takes over. Undersize that buffer and the line re-sterilizes far too often.

Deposits change character with temperature: below about 110 °C mainly protein with some mineral, above it hard mineral scale dominated by calcium phosphate. Preheat design, water quality, product hydration and flow regime move run length far more than the sterilizer does. Published figures put cleaning at 30 to 80% of operating costs in dairy plants.

A UHT heat treatment changes flavor slightly and reduces some heat-sensitive vitamins, so nutritional value is one of the things the process window protects. Heat-resistant enzymes from poor raw milk survive the treatment and can gel or embitter the product months later. And the capital only pays when the product truly travels without a cold chain, not when you refrigerate it anyway.

It is calculated from a configuration, not from a capacity figure: heating route, capacity, scope of supply, filler class, automation level and heat recovery. Two lines rated for identical throughput can differ widely once the scope changes. We price one defined configuration and list what is excluded, so competing offers compare line by line.

A complete line runs 4–8 months from drawing approval, and a single machine or process module runs 30–45 days. The clock starts at drawing approval because that is what releases material purchasing and panel build. Registration and packaging approval in your market run in parallel and are often the longer path.

Yes, our turnkey scope covers the value chain from milk reception through preheating, homogenization, sterilization and the aseptic tank, to the filler, the coder and the end-of-line packer. Most of that scope we build ourselves; the rest we buy in, integrate and warrant inside the same contract. You can also buy any single block of that scope on its own.

Every circuit is run on water and pressure tested, the line is sterilized with hot water at production temperature, and your product or the closest match is run at your parameters. You witness the test on site or by live video against a checklist agreed in advance. Nothing is packed until every point is signed.

Operating and maintenance manuals, process description, valve and instrument lists, electrical drawings, calibration records, and material certificates for the parts that carry them. Certification scope such as CE, SGS, ISO 9001 and ISO 27001 is confirmed case by case against your model, configuration, manufacturing base and destination country.

Steam, electrical power, chilled water, cooling water and clean compressed air, all sized from your capacity and heating route. Direct steam injection needs culinary steam and more of it, while indirect lines with high regeneration need less steam and more heat exchanger surface. The utility schedule is issued with the proposal.

We accept a minimum order of one set, so a single machine or a small process block is a normal order rather than an exception. Pilot-scale lines are quoted the same way as production lines: against product, capacity and pack format.

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