Methods for reducing soluble metal ions in diatomaceous earth filter aids
US9005687B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 15, 2010 |
| Grant date | Apr 14, 2015 |
| Priority date | — |
| Expiry date | Aug 6, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC12H1/0408
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method for reducing the amount of beverage soluble metal ions in a diatomaceous earth filter aid is disclosed. The beverage soluble metal ions can be copper and/or iron. In the method, the diatomaceous earth filter aid is contacted with a hop compound selected from iso-alpha-acids, dihydroiso-alpha-acids, tetrahydroiso-alpha-acids, hexahydroiso-alpha-acids, alpha-acids, and beta-acids. The diatomaceous earth filter aid can also be contacted with and an acid other than the hop compound such as phosphoric acid. The iso-alpha-acids, dihydroiso-alpha-acids, tetrahydroiso-alpha-acids, hexahydroiso-alpha-acids, alpha-acids, or beta-acids bind the copper and iron metal ions and/or change the form of copper and iron in diatomaceous earth so the copper and iron are rendered substantially insoluble in a beverage such as beer. A method for filtering a beverage using the treated diatomaceous earth filter aid is also disclosed. A method for increasing the flavor stability of a malt beverage filtered with a diatomaceous earth filter aid is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.