Compostable vs. plastic: what California kitchens need to know.

California's packaging rules are changing fast, and "compostable" doesn't mean what most people think it means. Here's a practical walkthrough of the materials, the regulations, and what it actually costs to switch.

First: what does "compostable" actually mean?

The word gets stretched a lot in marketing, but it has a specific technical meaning. A package is genuinely compostable only if it breaks down into water, CO₂, and biomass in a commercial composting facility within a defined time window — typically certified by BPI (Biodegradable Products Institute) in the US.

Things that are not compostable, even if the label sounds green:

• "Biodegradable" plastics — these break into smaller plastic pieces, often microplastics, but don't return to nature.
• Most "bioplastic" or "plant-based" containers without a BPI certification.
• Paper or kraft items with a plastic lining (unless that lining is also certified compostable, like PLA on bagasse).

The materials that actually work

Bagasse

Made from sugarcane fiber left over after juicing. Sturdy, microwave-safe, freezer-safe, holds heat, holds liquid for short periods, BPI-certified compostable. The workhorse of compostable food trays and plates. The downside: less leak-resistance over hours than plastic, so it's not ideal for very saucy items left sitting.

Kraft paper (with compostable lining)

Great for take-out boxes, food pails, bags, and cup sleeves. The kraft itself is fine; what matters is the lining and adhesive used. Look for PFAS-free certifications specifically — some older kraft items used PFAS coatings for grease resistance.

PLA (polylactic acid)

Made from corn or sugarcane. Looks and feels like clear plastic, used most often for cold cups and clear lids. BPI-compostable but only in commercial facilities — it will not break down in a backyard compost. Doesn't tolerate hot drinks.

CPLA

Crystallized PLA — the heat-tolerant version used for hot cup lids and cutlery. Higher temperature rating than plain PLA.

What California law actually requires

The regulatory landscape changes regularly, but the headline items are:

• SB-1383 (organic waste). California requires businesses to divert organic waste, including compostable packaging, from landfills if a composting facility is accessible. Many cities have local enforcement schedules tied to this.
• PFAS bans on food packaging. California has restricted the use of intentionally-added PFAS ("forever chemicals") in food packaging. If your supplier can't provide PFAS-free documentation for any paper or fiber product, that's a problem.
• Local ordinances. Many Bay Area cities (San Francisco, Berkeley, Alameda, and others) have ordinances that go further than state law — for example, banning specific plastic items in food service.

The practical takeaway: if your packaging supplier can't tell you the material composition and certifications of every fiber-based product they sell you, switch suppliers. Documentation matters more than marketing.

"The customers who get this right don't switch everything at once. They start with the items most visible to the customer — the takeaway box, the cup — and work backwards from there."

The cost difference, honestly

Compostable typically costs 15–60% more per unit than equivalent plastic, depending on the item:

• Hinged clamshells: Bagasse runs ~25–40% more than mineral-filled plastic.
• Hot cups: PLA-lined kraft is ~20–30% more than poly-lined paper.
• Cold cups: PLA clear cups are ~30–50% more than PET clear cups.
• Cutlery: CPLA is roughly 2× the cost of standard PP plastic.
• Plates and trays: Bagasse is generally only 10–20% more than foam — and the foam ban makes the comparison moot in many cities anyway.

For a typical fast-casual operation, a full switch to compostable raises packaging cost-of-goods by roughly 0.5–1.5 percentage points. Often that's recoverable through a small menu price increase, especially if you communicate the switch on the menu or packaging itself.

The smart way to phase the change

If you're moving toward compostable but not in one jump, here's the order most kitchens find easiest:

1. Cutlery and straws first. Cheapest items, lowest cost impact, most visible to the customer.
2. Cold cups next. PLA is a clean swap for PET in most cases.
3. Plates and trays. Bagasse is a mature, reliable category.
4. Hinged clamshells and take-out boxes last. These are the bigger cost lines, so do them once your menu and volume are stable.

One last thing: compost is only compost if it goes in the right bin

Compostable packaging only works if it actually reaches a commercial composting facility. If it ends up in landfill, it behaves much like regular trash. Talk to your waste hauler about a green bin pickup; in most Bay Area cities, that's already part of standard commercial waste service.