Injector needle glossary: terms used across brands and machines
An injector needle glossary is a reference list of the terms used to describe brine injection needles across machine brands. Bore, wall thickness, hole pattern, forged tip, quadro, pickle and yield mean the same thing on every production line, even where each machine builder writes them differently.
An order that says only “4 mm needle” describes the outside of the tube. The bore inside it sets the yield and can differ between two 4 mm needles, so we ask about both.
A to B
Aftermarket needle
An aftermarket needle is a needle made by a specialist needle maker rather than by the company that built the injector. We make aftermarket needles to our own designs.
Bore (internal diameter)
The bore, also called the internal diameter, is the open channel inside the needle tube. Bore size governs how much brine passes per stroke, so yield follows bore, not outer diameter.
Brine
Brine is the liquid injected into meat, poultry or fish, typically water with salt, spices and additives such as phosphates or nitrites. How thick the brine is tells us which outlet to recommend: side holes for liquid brine, one large opening for dense marinades.
Burr
A burr is a raised edge of metal left around a drilled hole or machined surface. Burrs tear muscle fiber and collect residue, which is why we grind and polish our needles so that burrs do not form.
C to H
CIP (clean-in-place)
CIP, short for clean-in-place, is an automated cycle that pumps water and cleaning solution through the injector circuit and the needle head without manual disassembly, so the needles are cleaned from the inside.
Electropolishing
Electropolishing is an electrochemical process that dissolves the microscopic peaks left by drawing and machining. We electropolish our needles inside and out, which lowers bacterial adhesion and helps keep the bore clear.
Forged tip
A forged tip is a point formed by rolling the tube until it closes, so tip and tube stay one piece. Every round tip we make is forged.
Hole pattern
A hole pattern is the number, diameter and placement of the outlets through which brine leaves the needle. Holes close to the tip fill the meat instead of leaking.
I to N
Injection pressure
Injection pressure is the pressure at which brine is forced through the needles into muscle tissue. Pressure, bore and hole pattern work together, so when a plant switches to a different needle, the pressure setting is worth checking again.
Needle fitting
A needle fitting is the connection by which a needle attaches to the needle head. Each injector manufacturer uses its own type of fitting, so the fitting is one of the first things we ask about in an order.
Needle head
A needle head is the block that holds the needles and feeds brine to each of them. One head may carry a handful of needles or as many as several hundred, and the layout differs from one machine series to the next.
Needle plate
A needle plate is the drilled plate inside a needle head that holds each needle in position and sets the spacing. We call the whole assembly a needle head.
O to Q
OEM needle
An OEM needle is a needle supplied under the brand of the company that built the injector, OEM meaning original equipment manufacturer. The term describes the sales channel through which the needle reaches the plant.
O-ring
An o-ring is a rubber sealing ring that closes the joint between needle and needle head so brine cannot escape. We fit a food grade rubber o-ring, NBR 70 or similar, as standard wherever the design requires it.
Outer diameter
Outer diameter is the external width of the needle tube and the figure most catalogs quote first. Our range starts at 1.6 mm and goes up to 6 mm, with the most common sizes spaced half a millimeter apart from 2 mm upward.
Perforated needle
A perforated needle is a needle with several holes in the tube wall, made to distribute liquid brine evenly. Perforated needles suit brines free of solid particles.
Pickle
Pickle is the word many English-speaking meat plants use for curing brine itself, the liquid injected into the product. In our own documents we use brine and curing solution.
Quadro needle
A quadro needle is an assembly in which four tubes share one head, so a single position in the needle head injects through four tubes at once.
R to Y
Replacement needle
A replacement needle is any needle fitted in place of a worn or damaged one, whatever its origin. Replacement needles must match the fitting, length, diameter and hole pattern.
Silver soldering
Silver soldering is a joining method that draws a silver-bearing filler into a joint below the melting point of the parent metal. We use it underneath the head, where it seals the joint against brine in a spot that no cleaning cycle can reach.
Single needle
A single needle is an assembly with one tube on one head, the configuration used for most general-purpose injection work. With one bore per position, a single needle is simpler to inspect.
Tenderizing knife (tenderizing blade)
A tenderizing knife, also called a tenderizing blade, is a bladed tool fitted in a meat injector. It cuts the tissue as the brine goes in, and that cut helps the product hold the liquid, which shows in flavor and tenderness.
Thick brine tip
A thick brine tip is a needle point with one large opening instead of small side holes. Thick brine tips are meant for dense marinades and for brines containing particles that would block small outlets.
Wall thickness
Wall thickness is half the difference between the outer diameter and the bore, because the wall runs on both sides of the tube. For a given outer diameter, a thicker wall means a smaller bore and less brine per stroke.
Yield
Yield is the weight of finished product obtained from a given weight of raw material, expressed as a percentage. Yield depends on brine, settings and bore, which is why we treat internal diameter as a yield parameter.
Terms most often confused
| Term | Confused with | Difference |
| Bore | Outer diameter | Catalogs list outer diameter; brine passes through bore |
| Perforated needle | Thick brine tip | Side holes for liquid brine; one opening for marinade |
| Single needle | Quadro needle | One tube per position against four |
| Brine | Pickle | The same liquid; pickle is more common in English-speaking plants |
Using these terms when ordering
Each brand page on our site lists the codes we supply per series: FOM Needles suitable for Fomaco injectors, SCH Needles suitable for Schroder injectors, INJS Needles suitable for Inject Star injectors and METQ Needles suitable for Metalquimia injectors. We design and manufacture every needle ourselves and are not an agent of any of these companies. In our codes D is the diameter, L the overall length.
A request written in this vocabulary answers most of our questions: brand and series, fitting, length, outer diameter, bore, hole pattern, tip type, single or quadro, and the brine. See also needle head and injector needles.
Key takeaways
- Outer diameter identifies a needle in a catalog; bore and wall thickness determine flow and yield, so state all three.
- Hole pattern and tip type follow from the brine: perforated for liquid brine, a thick brine tip for dense marinades.
- Configuration is either single or quadro, one tube or four on one head, which changes the number of injection points while the flow through each bore stays the same.
- OEM and aftermarket describe where a needle is bought.
Frequently asked questions
What is the difference between bore and outer diameter on an injector needle?
Outer diameter is the external width of the tube and the figure catalogs list first. Bore, or internal diameter, is the channel inside it. Two needles of the same 4 mm outer diameter can have different bores, because wall thickness differs, and the one with the larger bore passes more brine per stroke.
Is a quadro needle the same as four single needles?
A quadro needle is one assembly in which four tubes share a single head, so it occupies one position in the needle head and is fitted, cleaned and replaced as one part. Four single needles occupy four separate positions. Quadro raises the number of injection points without changing the head layout.
Does pickle mean something different from brine?
Pickle and brine describe the same thing in day-to-day plant language: the liquid injected into the product. Pickle is heard more in English-speaking plants and in older technical literature. In our own documentation we write brine and curing solution, and we treat an order written with either word the same way.
What do the letters in a needle code such as FOM L305 D4 mean?
In our ZUST Needles codes, the letters at the front identify the machine family a needle is made for, L gives the overall length and D the diameter. FOM L305 D4 quadro is therefore a quadro needle 305 mm long with a 4 mm outer diameter, made for Fomaco injectors, to our own design.
How ZUST can help
We manufacture injection needles for meat, poultry and fish processing to our own designs, in the configurations and hole patterns described above, for OEM customers, spare parts suppliers and processing plants buying directly. Codes per machine brand are listed on our products page, and if the term you need is missing from this injector needle glossary, send us the machine and the product you run through our contact page.