Glass
| ABNSABNS — Acid-Based No-Rinse Sanitiser The class of acid-based sanitisers used in homebrewing, combining phosphoric acid with an anionic alkylbenzenesulfonate surfactant. The acid creates a low-pH environment hostile to microorganisms; the surfactant disrupts cell membranes. Examples: Star San, Sanipro Rinse, StellarSan, Chemsan. Approved for use on food-contact surfaces without rinsing when used at the manufacturer's specified dilution. | DESDES — Disinfectant Ethanol Sanitiser ChemiPro DES. An ethanol-based (70–80%) sanitiser with no non-volatile residue. Evaporates completely, leaving no WDC risk. A-rated for all common homebrewing materials. | Cleaning | Beer/wortWort Liquid extracted from malted grain during mashing and boiling, before fermentation. The starting point for beer. | |
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| Rating | A | A | A | A |
Glass (borosilicate and soda-lime) is chemically inert to all homebrewing chemicals at ambient temperature and normal concentrations. It is the reference material against which food contact safety testing is calibrated — EU food contact simulant A is distilled water; simulant B is acetic acid solution — both chosen to simulate conditions that glass vessels already handle without concern.
Glass appears in homebrewing as airlocksAirlock A one-way valve fitted to the fermenter lid that allows CO₂ produced during fermentation to escape while preventing air and contamination from entering. Filled with sanitiser solution or cooled boiled water. The rate of bubbling gives a rough indication of fermentation activity, but the absence of bubbling does not confirm fermentation is complete — gravity measurement is the reliable indicator. 3-piece and S-type designs are both common and functionally equivalent for homebrew use., test jars, hydrometer cylinders, fermenters (carboys), and bottles.
Food contact status
Glass is listed under EU Regulation 1935/2004 as a permitted food contact material. No migration limits apply under normal use conditions — the basis of glass food contact compliance is its chemical inertness rather than a specific migration limit framework.
Compatibility — ABNS / DES / Cleaning / beer/wort: A
No compatibility concern in any homebrewing chemical environment. Glass is the one material in this register that carries no caveats.
A note on microplastics
One counterintuitive finding from recent research: glass bottles have measured higher microplastic content than PETPET — Polyethylene terephthalate The plastic used in the FermZilla All Rounder, Oxebar mini keg, and PET bottles. Recycling code ♻️1. Extensively tested for food contact with carbonated beverages. Do not exceed 40 °C when cleaning. bottles in some studies, including ANSES 2025 data. The source is environmental contamination during manufacturing and filling, not migration from the glass itself. This does not affect the food contact or chemical compatibility rating of glass, but it is relevant context for the microplastics discussion — see Microplastics.