A dairy plant is a sequence. Raw milk arrives, is stored, cleaned, separated, standardized, homogenized, pasteurized, and either packaged or turned into cultured products, cheese, or ice cream mix. At each step, a specific dairy tank or processing machine does the work.
Understanding that sequence helps buyers see which equipment they need, how each machine connects to the next, and where used dairy processing machinery can fill a gap in the plant. Used Packaging Equipment has sold used processing, bottling, and packaging machinery since 1988, serving dairy, beverage, food, and nutritional producers. This guide follows milk through a typical dairy plant and answers the most common questions about the tanks and processing machines along the way.
A dairy tank processing machine is any tank, vessel, or processing system used to store, treat, or prepare milk and dairy products. The category includes raw milk silos, balance tanks, separators, homogenizers, pasteurization systems, processing vats, mixing tanks, and the clean-in-place systems that keep them sanitary. Most are built from stainless steel with sanitary fittings and smooth interior surfaces designed for daily cleaning.
Raw milk arrives by tanker truck and is unloaded at a receiving bay. Receiving systems typically include a sanitary pump, a flow meter to measure the volume received, a filter or strainer, and sometimes an air eliminator to remove air before metering.
From receiving, milk is pumped into raw milk silos or storage tanks. Silos are large vertical tanks, often installed outdoors with only the outlet and controls inside the plant. Smaller plants may use horizontal or vertical storage tanks indoors. Storage tanks are insulated and include agitators to keep milk uniform.
Raw milk must be kept cold until it is processed. Many plants cool milk on receiving with a plate heat exchanger before it enters storage. Storage tanks are insulated to hold that temperature. Always follow the cooling and holding requirements set by your regulatory authority.
A centrifugal separator spins milk at high speed to divide it into skim milk and cream. Separators may also be used to clarify milk by removing sediment and other solids.
After separation, cream and skim are blended back together at the ratio needed for the product, such as whole milk, reduced-fat milk, or skim. Some plants standardize in-line with automated systems, while others blend in batch tanks.
A balance tank holds a small volume of product ahead of processing equipment so the flow into a pasteurizer or homogenizer stays steady. It acts as a buffer between batch storage and continuous processing.
A homogenizer forces milk through a narrow valve under high pressure, breaking fat globules into smaller particles. This keeps cream from separating and rising to the top. Homogenizers are used for fluid milk, cream products, ice cream mix, and many plant-based beverages. They are piston pumps at heart, so buyers should ask about piston and valve components and verify pressure ratings against the specific machine.
High-temperature, short-time (HTST) systems pasteurize milk continuously as it flows through a plate heat exchanger, a holding tube, and a flow diversion valve. HTST systems are the standard for most fluid milk plants.
Smaller operations, specialty dairies, and some cheese and cultured product makers use batch pasteurization. Milk is heated and held in a jacketed vat, then cooled. Batch pasteurizers are common in farmstead and small-scale dairies.
Ultra-high-temperature systems are used for shelf-stable and extended shelf life products. They are more complex and are typically paired with aseptic or extended shelf life filling.
Pasteurization equipment is regulated. Used systems typically need to be reviewed, sealed, and approved by the appropriate regulatory authority before use. Ask for documentation, controls information, and any history available for the system, and involve your inspector early.
Yogurt, sour cream, kefir, and buttermilk are made in jacketed processing vats where milk is heated, cultured, held, and cooled. These vats usually include agitation and temperature control.
Cheese vats hold milk while it is cultured, coagulated, cut, and cooked. Open vats, enclosed vats, and double-O style vats are all used depending on the cheese. The vat style affects how curd is cut, stirred, and drained.
Ice cream mix is blended, pasteurized, homogenized, and then aged in jacketed tanks before freezing. Mix tanks need good agitation for thick, high-solids products.
Multi-use processors and jacketed kettles heat, mix, and cool products in batches. Many dairies use them for specialty products, sauces, and small runs.
Clean-in-place, or CIP, systems clean tanks, lines, and processing equipment without taking them apart. A CIP system typically includes tanks for rinse water, cleaning solution, and sanitizer, along with pumps, heating, and controls that circulate each solution through the equipment.
Tanks are fitted with spray balls or rotating spray devices that distribute cleaning solution across the interior surfaces. Confirm that a used tank’s spray devices suit your CIP system.
A used tank needs to fit into your cleaning program. Ask whether the tank was designed for CIP, what spray devices it has, and whether its fittings match your CIP supply and return lines.
After processing, milk and dairy products are stored in finished product tanks, sometimes called surge or filler supply tanks, until they are packaged. These tanks let processing and filling run on separate schedules, so a short stop at the filler does not force processing to stop as well. From there, product flows to fillers for gallons, half-gallons, bottles, cups, or cartons, followed by capping, coding, and case packing.
Verify capacities, pressures, and temperatures against the specific machine’s specifications and your regulatory requirements.
Used Packaging Equipment has specialized in used processing, bottling, and packaging machinery since 1988. Our inventory includes dairy tanks, processing vats, jacketed kettles, mixers, sanitary pumps, and filling equipment for dairy, beverage, food, and nutritional producers. Financing is available to help you add processing capacity without straining your budget.
Contact our team with the products you make and the step in your process you are building out, and we will help you find used dairy processing equipment that fits.
© 2024 Used Packaging Equipment, LLC. All Rights Reserved.
Website Design & Development by Gibson Design, Fate, Texas
