加工・条件 / process-dry-hopping

ドライホッピング

dry hopping

Addition of hops to beer after or during cold fermentation rather than to the boiling wort, without α-acid isomerization.

加工・調理でどう変わる（2）

ドライホッピングは苦味単位（BU/IBU）を増加させる支持あり

範囲: Pilot-scale dry hopping of an unhopped ale at 0-16 g/L for 0-72 h, plus a survey of 15 commercial Pacific Northwest beers sampled pre- and post-dry-hop

注記: The two halves move in opposite directions: the conventional IBU proxy goes up while the compound class it is meant to proxy goes down. This is the central falsification material for treating IBU as an iso-α-acid readout.

A trained sensory panel quantified increases in bitterness from dry hopping an unhopped ale at 0-16 g/L for 0-72 h, alongside IBU and hop acid and polyphenol measurement. The increase in beer bitterness (IBU) resulting from dry hopping was attributed to humulinone extraction and, in some cases, polyphenol extraction. A parallel survey of 15 commercial beers sampled pre- and post-dry-hop noted a decrease in total iso-α-acid concentrations in a majority of the samples tested, indicating that the dry-hopping process may remove iso-α-acids from beer.

限界: Abstract-level extraction. Panel size, IBU magnitudes and iso-α-acid concentrations are not given in the abstract, and the paired sensory result for the commercial survey is not stated. The abstract still names iso-α-acids the main contributor to beer bitterness overall, so this is a qualification of the IBU proxy rather than a displacement of iso-α-acids.

出典: Toward Understanding the Bitterness of Dry-Hopped Beer（Parkin E; Shellhammer TH, 2017）・抄録確認

データを表示

process-dry-hopping —increases→ concept-bitterness-units

claim: clm-dry-hopping-raises-ibu-lowers-iaa / type: processing / 更新: 2026-08-30

フムリノン類はドライホッピングによってビールへ抽出される支持あり

範囲: Dry-hopped beers in a pilot-scale study, a 15-beer commercial survey, and a three-variety hop-freshness trial

注記: Refines existing clm-beer-contains-humulinones and clm-humulinones-beer by naming the process route. The '66% as bitter as iso-α-acids' figure appears in the reviewed literature as a citation of earlier work and is recorded in the evidence limitations rather than in this claim.

Although iso-α-acids were the main contributor to beer bitterness overall, humulinones (oxidized α-acids) and polyphenols were also potentially significant contributors to bitterness, particularly in heavily dry-hopped beer, and the IBU increase from dry hopping was attributed to humulinone extraction.

限界: Abstract-level extraction; the wording 'potentially significant' is the authors' own hedge and is retained here. No isolated-compound omission or addition test is reported in the abstract.

出典: Toward Understanding the Bitterness of Dry-Hopped Beer（Parkin E; Shellhammer TH, 2017）・抄録確認

The introduction notes that 'For a long time, dry hopping was not considered to contribute to bitterness, since no isomerisation of alpha acids occurs', and that humulinones are oxygenated products of alpha acids whose levels increase during hop storage and which are approximately 66% as bitter as iso-alpha acids. The conclusions state that 'In dry hopped beers, the main source of bitterness is humulinones, which are increasing and, at a certain HSI, started to drop; this is due to the further oxidation of humulinones to oxidation products'.

限界: The '66% as bitter as iso-α-acids' figure and the historical framing are cited from earlier literature inside this paper's introduction, not measured here, so they are recorded as context and not promoted to a claim. The 'main source of bitterness' statement is the authors' conclusion about their dry-hop-only beers and does not generalize to kettle-hopped beer.

出典: Impact of Hop Freshness on Dry Hopped Beer Quality（Rutnik K; Ocvirk M; Košir IJ, 2022）・全文確認

データを表示

compound-humulinones —is_extracted_into_beer_by→ process-dry-hopping

claim: clm-humulinones-dry-hop-extraction / type: processing / 更新: 2026-08-30

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