CHIZU — the atlas of coffee research
Coffee research in Portugal
Two limits come with this count. Only 100,474 of the 190,643 searchable papers (52.7%) carry an author affiliation country. The other 90,169 (47.3%) carry none. So these 1,244 papers are 1,244 out of the 100,474 whose affiliation is known. And a co-authored paper is counted once for every country its authors sit in. Per-country counts therefore do not add up to the whole.
Portugal does not grow coffee, but coffee is researched there.
Check it yourself
This is not our word for it. You can run the same query against the same index.
When they were written
1830–2026
Years before 1600 are treated as unknown. The upstream data (OpenAlex) sometimes writes 1400 when the year is missing, and that is a placeholder, not a measurement.
Where they appeared
Top 8 sources (journals and repositories)
Most cited
10 papers, most cited first
- Natural Deep Eutectic Solvents – Solvents for the 21st Century2014cited 2,398
- Production, Composition, and Application of Coffee and Its Industrial Residues2011cited 1,001open access
- Chemical, Functional, and Structural Properties of Spent Coffee Grounds and Coffee Silverskin2014cited 860open access
- Impacts of drought and temperature stress on coffee physiology and production: a review2006cited 669open access
- Adenosine receptors in the nervous system: pathophysiological implications2002cited 514
- Electrolyte leakage and lipid degradation account for cold sensitivity in leaves ofCoffea sp. plants2003cited 510
- Encapsulation of antioxidant phenolic compounds extracted from spent coffee grounds by freeze-drying and spray-drying using different coating materials2017cited 451open access
- A study on chemical constituents and sugars extraction from spent coffee grounds2010cited 440open access
- Extraction of antioxidant phenolic compounds from spent coffee grounds2011cited 433open access
- Conventional and microwave induced pyrolysis of coffee hulls for the production of a hydrogen rich fuel gas2006cited 357open access
Which stage of coffee
Only 30.2% of the whole index carries a stage label. Of this country's 1,244 papers, 479 carry one. The breakdown below is about those 479 papers only — the rest were never candidates for it.
One paper can carry several labels, so the breakdown adds up to more than that number.
Which field
Only 75.9% of the whole index carries a field label. Of this country's 1,244 papers, 1,028 carry one. The breakdown below is about those 1,028 papers only — the rest were never candidates for it.
One paper can carry several labels, so the breakdown adds up to more than that number.
What language
"undetermined" means the upstream record carried no language. We did not guess one.
Knowledge is not evenly spread
Counting only papers whose author affiliation is known, the largest is Indonesia with 22,248. Portugal has 1,244 — a factor of 18.
That gap does not follow where coffee is grown. Research gathers where the means to do research are, not where the coffee is. Making that visible is why CHIZU exists.
Other countries
Indonesia 22,248United States 17,988Brazil 10,857United Kingdom 5,569China 4,887India 3,542Germany 3,185Italy 3,111France 3,072Japan 2,822Colombia 2,489Spain 2,363