Food Contact Is a Materials Decision Before It Is a Design Decision

A kitchen product looks like an easy first project. It is small, it has no firmware, and everyone understands what it does. The complication is that the moment a surface touches food, the material list shrinks dramatically and the cost per pound goes up. Choose the shape first and you will discover halfway through that the resin you drew around is not cleared for food contact at the temperature your product sees.

In the United States, food-contact materials are governed by FDA regulations under 21 CFR, and the practical requirement is a letter of compliance from the resin supplier stating that the specific grade is suitable for the food type and temperature you intend. "Food safe" on a marketing page is not the same thing. Ask for the grade number and the compliance statement, and get it before tooling. The food-grade plastics guide covers which families qualify and where the exclusions sit. If you are exporting, the EU food-contact plastics regulation has its own positive list and its own overall and specific migration limits, and the two frameworks do not fully overlap.

The Real Duty Cycle: Heat, Detergent, and Abrasion

Kitchen products fail in dishwashers, not in use. A residential dishwasher runs a wash cycle around 120 to 150 F (49 to 66 C) with a high-alkalinity detergent and a heated dry that can push local surfaces past 160 F (71 C). That combination hydrolyzes some polyesters, crazes polycarbonate over repeated cycles, and lifts printed graphics. Write the duty cycle into the requirements document as a number: 300 dishwasher cycles, 60 days of contact with acidic food, 2,000 open-close cycles on any lid.

Common material choices and what they buy you:

  • Polypropylene. Cheap, food-contact friendly, tolerates dishwashers well, up to roughly 250 F (121 C) short term. Poor clarity, scratches easily.
  • Tritan copolyester and similar. Glass-like clarity without bisphenol-A, good impact strength, more expensive than PP and softer than glass.
  • Silicone (LSR). The right answer for seals, spatulas, and anything that must survive an oven. Liquid silicone rubber tooling is expensive but cycle times are fast.
  • Stainless 304 and 18/8. Perceived quality, no leaching questions, but a different supply chain and a much higher tooling cost for deep-drawn shapes.

Polycarbonate deserves a separate note. It is tough and clear, but consumers actively look for BPA-free labeling, and even BPA-free PC grades carry a market perception problem in food contact. The acrylic versus polycarbonate comparison is a useful sanity check when clarity is a requirement.

The Product Is Judged in the Hand

Kitchen tools are bought after a two-second grip test in a store aisle or after reading a hundred reviews written by people describing how the handle felt. Grip diameter, the angle between handle and working end, and where the weight sits decide the review. Design against real hand data rather than your own hand, using the percentile ranges discussed in ergonomics in product design, and check the extremes: arthritic hands, wet hands, and left-handed users.

Wet-hand grip usually means a TPE overmold on a rigid core. That is a two-shot or insert-molded part, which roughly doubles tooling cost and adds a material-compatibility question, since not every TPE bonds to not every substrate. Confirm the bond pair with the molder before the design is frozen; overmolding and two-shot molding explains where the money goes.

Designing for the Shelf

Retail buyers think in facings and pegs. Your product has to hang or stand within a defined width, show its function without a demo, and survive being handled by shoppers. Nesting matters too: a set that stacks compactly lowers freight cost per unit and takes less shelf space, which is a genuine argument in a buyer meeting. Work the packaging in parallel with the product rather than after it, along the lines set out in product packaging design.

Color and finish carry more weight in this category than in most. A kitchen product sits on a counter, so it competes with the customer's existing appliances. A neutral core color with a small accent range is usually the safer opening lineup, and adding colors later is a resin change rather than a tooling change.

Tooling, Volumes, and Unit Cost

A single-cavity aluminum mold for a hand-sized kitchen part typically runs $6,000 to $18,000 domestically or less overseas, with steel multi-cavity tooling for volume production landing between $20,000 and $60,000 per part. Per-part molded cost at a few thousand units is often $0.60 to $3.00 depending on shot weight and cycle time. Those numbers move fast with wall thickness and part complexity, which is why the geometry decisions in injection molding cost deserve attention before the CAD is finished.

Retail math sets the ceiling. A product that sells for $24.99 at retail generally needs a landed cost near $4 to $6 to support distributor and retailer margins. Calculate backward from that number and let it constrain the design, rather than designing first and discovering the margin is not there.

Testing and Claims

Plan for third-party testing on migration or extraction if you make specific food-safety claims, dishwasher cycling to your stated count, and drop testing onto tile. If the product heats food, add thermal cycling and a surface-temperature check on anything a user touches. Where a claim like "BPA-free" or "dishwasher safe" appears on packaging, keep the supporting test report on file; the broader landscape is mapped in product safety testing requirements.

Get Your Kitchen Product Made

Projects House takes kitchen and housewares products from concept through food-contact material selection, ergonomic prototyping, tooling release, and first production run with a vetted molder. Send a sketch or a description through our contact form and we will outline the material path, the tooling budget, and the schedule.