Vitamin Gummy Mold Solutions for Piece-Weight Control

If you're tooling a vitamin gummy line, the mold is a cavity-volume tool on a hygienic deposit-dump belt.

You own the formula, the label, and any nutrient claim. We own a fillable cavity with a repeatable volume, an array that matches the depositor, a dump that doesn't tear, and a food-contact RTV tray under 21 CFR 177.2600 extractives and LFGB/BfR XV. Starch moguls still make candy bears; a lot of vitamin rooms won't take starch dust. Don't ask us how many IU belong in a bear — that's formulation, not tooling.

Piece-weight is geometry plus slurry, not a magic compound

QC will weigh pieces. Mass is slurry density times filled volume, plus skin loss that isn't our business. What actually moves the scale: freeze milliliters before the mascot outline; design a fill-to-brim cup or a visible fill line, not a porous charm that traps air; radius paths into thin features so the shot doesn't starve ears while the belly floods; match cavity-to-cavity volume across the array (same master, same shrink, same flash rule); prove one cavity with water and with plant slurry before you cut 40 cavities into the master.

Inclusions (beads, grit, oil droplets) change fill and dump. Send them as a process note, not as a request that we formulate a vitamin premix.

If piece-weight drifts later, split it: depositor shot, slurry density batch-to-batch, and cavity volume (flash, dirt, ovaling after hot wash). The mold is only the third term. Ovaling after a stacked wash is a jacket-stiffness and ASTM D395 conversation.

Why vitamin halls drop starch on some SKUs

Starch moguls are excellent candy tools. Vitamin plants often reject them because of dust in a room that also weighs actives, starch on the piece, logos the print can't hold, or short branded runs where mogul changeover is the expensive step. Then you're usually on a platinum RTV tray (often jacketed) or a rigid plastic tray for simple cups. RTV wins when dump needs flex or the shape undercuts. PC wins when the cup is simple and the line already knocks. Hybrids exist when the depositor wants a stiff envelope and the cavity still needs rubber.

Don't reject starch as a moral position. Reject it when the room or the shape says so. Some co-packers still run starch for confection and RTV for vitamin SKUs on separate halls.

Throughput is nozzles times cycles. Size the array to the head you own. Extra cavities the head can't hit are ornaments. Family solutions: one jacket, several RTV faces at the same volume. Spare trays so the washer doesn't idle the depositor. Pigments stay in the food-contact package; a color change is a requalify.

Common mix-up: milligrams of vitamin C as a steel dimension

A lot of RFQs treat "500 mg per gummy" as a cavity spec. In the shop that usually means you've asked us to assay a nutrient. We can hold milliliters. Your formulator puts the nutrient into the slurry at a concentration that hits the label when mass is in range. ISO 10993 and USP Class VI are the wrong file unless someone is actually making a medical device, which this mold isn't. Don't buy "FDA approved" or "medical-grade" as a substitute for named extractives.

The gummy may be food or dietary supplement depending on market and claims. The mold is still repeated-use rubber: 21 CFR 177.2600 extractives on the post-cured tray, LFGB/BfR XV when that's the bar. Wash chemistry and temperature should match what the lab washed. We can keep a dedicated master and a clean pack-out; we can't write your 21 CFR 111 program. Platinum chemistry, post-cure, no tin-cure repair beads.

What to ask when you're buying a vitamin tray

• Target milliliters (or mass + measured density), fill-to-brim or fill-to-line?
• Is starch forbidden in that hall?
• Depositor pitch, pin pattern, dump motion?
• Shore of the RTV face, and is there a jacket so cavities don't oval in the washer?
• 177.2600 extractives and/or LFGB on *this* article, not a spatula and not ISO 10993?
• One-up or 2-cavity dump in plant slurry before the full array?
• Who owns the master, and is recast a line item?

Sampling path we'd push even if you're in a hurry: one-up or 2-cavity platinum RTV for volume and dump, adjust the master, production tray at real pitch with jacket, first-article volume/pitch/wash/identity, then spares.

Example

A typical first vitamin tray is 24 cavities, 2.0 ml ovals, 8 mm fill height, Shore 25A platinum RTV in an aluminum jacket, built for a few thousand dumps a month after a two-cavity pectin trial. Recasts use the same master unless QC changes milliliters.

When this vitamin-tray memo is the wrong program

If QA allows starch in that hall and the shape prints, a mogul can still be the right vitamin *candy* cousin — don't buy RTV as a moral upgrade. If you're asking us to guarantee milligrams of a nutrient or to write 21 CFR 111, that's formulation and plant GMP, not a mold PO. ISO 10993 / USP Class VI belong on devices, not on a gummy tray. Simple knock-dump cups on a line that already runs PC can stay plastic.

Related reading: designing vitamin cavities, supplement tray production, food-contact RTV.

What to send for a vitamin cavity quote

• Target grams (or ml + measured density) and allowed range
• Starch forbidden in that hall? Yes/no
• Nozzle pitch, pins, tray envelope, dump motion
• Gelatin vs pectin vs blend as a dump note; inclusions as fill notes
• Shore / jacket so cavities don't oval in the washer
• 177.2600 extractives and/or LFGB on the tray — not medical-grade as a slogan
• One-up dump in plant slurry before the full array?

Send grams, formula family, nozzle pitch, and tray size. We won't confirm IU per piece. We'll hold milliliters and dump geometry.

We would not recommend milligrams of a nutrient as a cavity spec

We would not recommend treating "500 mg per gummy" as a steel or RTV dimension. We hold milliliters; your formulator hits the label when mass is in range. We would not buy ISO 10993 / USP Class VI as a substitute for 177.2600 extractives. We would not skip the one-up dump in plant slurry to "save a week" on a vitamin array.

flowchart TD
  A[Target grams + density → milliliters] --> S{Starch forbidden in that hall?}
  S -->|no and shape prints| M[Mogul can still be the cousin]
  S -->|yes| G{Knock cup or flex/undercut?}
  G -->|knock cup| P[PC plate]
  G -->|flex / logo / undercut| R[Jacketed platinum RTV]
  R --> T[One-up in plant slurry → array]
  P --> T

Typical shop values: first vitamin jacketed tray

| Item | Typical shop value | | --- | --- | | Piece-weight target | 4.0 g (cavity volume × measured slurry density; fill-to-brim or fill-to-line stated) | | Outer-row vs center | 3–6% heavy if the loaded tray sags under the nozzles | | Loaded-tray edge sag | 0.5–1.5 mm without a flat jacket | | Cavity Shore | 10A–20A platinum RTV skin + rigid jacket | | Platinum linear shrink | 0.1–0.3% (cut the master so poured pitch lands) | | Mix | Platinum 1:1 or 10:1; pigment in the food-contact package | | Out of scope | IU / milligrams of a nutrient; 21 CFR 111 writing |

Caption these as typical shop values, not a measurement on your PO.

FAQ

Can a mold shop guarantee milligrams of vitamin C per gummy? No. We can hold cavity volume and fillability. Mass follows slurry density and depositor shot. Nutrient milligrams are formulation. Put mass range on the RFQ; keep assay out of the mold PO.

Why not use the same starch mogul as our candy line? You can if QA accepts starch in that hall and on that piece. Many vitamin programs don't. RTV or plastic trays are the usual split. Geometry can force RTV even when starch is allowed.

Do vitamin gummy molds need medical-grade silicone? Not by default. They need food-contact platinum RTV as an article under 21 CFR 177.2600 extractives and/or LFGB/BfR XV. ISO 10993 is a device question. Don't buy medical-grade as a slogan to skip food-contact flasks.

How many cavities should a first vitamin tray have? As many as the depositor will hit, after a one-up or two-cavity dump trial. Cavitation is a throughput buy, not a way to hide a bad cavity.

Will a hot washer change piece-weight over a month? It can, if cavities oval or pick up film. Design jacket stiffness and stacking, wash as specified, and spot-check volume. That's tray maintenance, not a vitamin reaction.