Dataset

The Three Counties perry pear survey

A modern survey of single-variety perry pear juices from Gloucestershire, Herefordshire and Worcestershire — the first dataset to separate the astringent phenolics from the ones that only brown, and the first to measure the nitrogen.

Why do perry ferments stick when cider ferments do not?

Because the nitrogen is not there, and a total amino acid figure hides it. This survey measured free amino nitrogen running from 70 mg/L down to 1 mg/L in perry pear juice, against typical cider apple figures several times higher — and beside it measured proline, an amino acid yeast cannot use without oxygen, which is frequently the largest single amino acid in the juice.

Tumper is the case that makes the point. Its proline is 337 mg/L against an assimilable pool of 7.8. A total amino acid figure would have called that juice well nourished. It is not, and a ferment given it will struggle.

The programme

Transcribed from the source as published. Nothing in this panel is CiderHQ’s wording.

Site: Gloucestershire, Herefordshire, Worcestershire and neighbouring counties — the perry country itself, rather than a research station elsewhere
Period: 2022–2024
Cultivars transcribed: 38
Measurements: 308
Values withheld: None
Classifies under: No classification scheme

Climate. The lower Severn and Wye vales: mild, wet, and the only ground in Britain where perry pears have ever been grown at scale. Fruit was collected across three autumns, and the survey reports each collection separately rather than pooling the seasons.

Method. Juice from single varieties, frozen before analysis. Specific gravity; titratable acidity by titration as malic acid; “true tannin” and phenolic acids measured as separate fractions; individual amino acids by HPLC, with free amino nitrogen calculated from them and proline reported apart because yeast cannot assimilate it anaerobically. Where samples differed by location, tree age or year, they are reported separately.

What the source says about itself

Ongoing survey work published openly and updated annually, by a technologist who has taught cider and perry production for decades. Not peer-reviewed; the author describes the fermentation trials in particular as initial surveys requiring statistical treatment before differences are called significant, and CiderHQ repeats that where the figures are used.

What it adds

It separates the phenolics. Historic perry tannin is a permanganate number responding to everything phenolic at once. This survey reports the polymerised fraction — the part that is actually astringent — apart from the phenolic acids, which brown readily and taste of very little. Butt at 3,000 mg/L true tannin against Wasserbine at 260 is a difference a drinker can feel; the phenolic acid column beside it is not.
It measures the nitrogen, and the individual amino acids, at a scale nobody else has attempted on perry fruit.
It shows the same variety twice, and publishes the repeats separately rather than averaging them. Oldfield’s true tannin is 690 mg/L in 2022 and 3,000 mg/L in 2024 — a bigger gap than most of the gaps between varieties.

What it cannot be asked

Stated as limits rather than as apology. A dataset with known bounds is more useful than one presented as complete.

Juices were collected, frozen and analysed rather than measured fresh at the press, and freezing is not nothing.
Sampling followed what was available across three seasons rather than a designed plan, so the varieties are the ones that fruited and could be reached.
Tree age, rootstock and site vary between samples and are not always recorded, which is part of why the repeats diverge so widely.

Why these figures are not universal

The survey’s own repeats are the argument. A perry pear’s composition is a statement about a tree, a season and a site, and this dataset measures the size of that statement rather than averaging it away: a fourfold range in true tannin within one variety across two seasons, and nearly threefold in acid between standard and bush trees of one variety in one month. Reading any single figure here as the value for the variety would be to discard the survey’s main finding.

What was measured

Every property in the transcription, with how many cultivars carry it. A property measured on some cultivars and not others is a gap in the source, not in the transcription.

Properties recorded across 38 cultivars in The Three Counties perry pear survey
Property	Cultivars	Reported in
Specific gravity	42	Specific gravity
Total tannin	38	Milligrams per litre
Phenolic acids	38	Milligrams per litre
Total phenolics	38	Milligrams per litre
Titratable acidity	37	Grams per litre
Total amino acids	37	Milligrams per litre
Free amino nitrogen	37	Milligrams per litre
Proline	37	Milligrams per litre
pH	4	pH

Total tannin across every cultivar in this dataset that carries it — 38 of them, from 3000 down to 260 mg/L. Every figure here comes from this one programme, measured by one method in one place, which is the only arrangement under which a comparison like this is sound. Nothing on this chart may be read against another dataset’s column.
Cultivar	Total tannin (mg/L)	Where it sits in this study’s range
Butt	3000
Oldfield	3000
Green Horse	2120
Blakeney Red	1170
Coppy	980
Tumper	920
Green Longdon	760
Moorcroft	760
Hendre Huffcap	750
Brandy	730
Betty Prosser	700
Bunch	700
Oldfield	690
Snake Pole	690
Ducksbarn	680
Felix	680
Green Roller	670
High Pear	640
Red Pear	640
Lumber	630
Hartpury Green	570
Newbridge	570
Barland	550
Green Horse	550
Old Home	530
Taynton Squash	500
Lullam	490
Blakeney Red	480
Thorn	470
Red Longdon	460
Butter Pear	440
White Longdon	440
Winnal’s Longdon	420
Barnet	410
Gregg’s Pit	410
Bartestree Squash	360
Hendre Huffcap	360
Wasserbine	260

Ordering only. Where a figure was published as a range the midpoint is used to place the row, and the range itself — not the midpoint — is what appears on the cultivar’s own page.

What it can be read beside

The commonest way to misuse this corpus is not to misread one figure but to put two side by side that were never measuring the same thing. This is the judgement, stated.

Whether The Three Counties perry pear survey may be read in one column with the site’s other datasets
Dataset	Verdict	Why
The Long Ashton perry pear analyses	Partly comparable	The same varieties in the same region sixty years earlier, and the pairing is the most interesting one on the site — but the tannin columns measure different things, so read them as two accounts rather than as a change over time.
The Klosterneuburg Mostbirnen trial	Not comparable	Austrian Mostbirnen, reported as tartaric acid rather than malic, on a different fruit repertoire in a continental climate. Both are perry pear datasets and neither can be read in the other’s column.

Where a dataset is not listed, no judgement has been recorded and the safe reading is that the two have not been checked against each other. CiderHQ never averages across studies: how evidence is handled sets out why.

Cultivars in this dataset

Each carries this programme’s figures on its own page, alongside whatever else has measured it.

Sources

What this page rests on. Where a source is marked as registered rather than read, CiderHQ is recording that the body is authoritative on the subject without claiming to have worked through the document itself. See our evidence policy for what each state means.

Perry Pears and Perry — Research and Survey Work
Cider and Perry Academy (Peter Mitchell) · specialist publication · passage verified 2026-08-25 · covers 2022–2024
Ongoing survey work by a cider and perry technologist who has taught production for decades, published openly and updated annually; retrieved and read in full on 2026-08-25. Thirty-eight single-variety perry pear juices analysed for gravity, titratable acidity, the tannin and phenolic acid fractions separately, and the individual amino acids by HPLC — the last of which nobody else has done at this scale for perry. Not peer-reviewed, and the author is explicit that the accompanying fermentation trials are initial surveys needing statistical treatment before differences are called significant; CiderHQ repeats that wherever the fermentation results are used.