{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T01:11:28Z","timestamp":1790212288720,"version":"4.1.0"},"reference-count":62,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,4]],"date-time":"2017-12-04T00:00:00Z","timestamp":1512345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>Methylxanthines present psychostimulant effects. These compounds have low toxicity and their consumption at moderate levels presents some beneficial health effects, whereas some significant risk appears at high levels. Samples of common types of methylxanthine-containing beverages and foods consumed in Spain were analyzed to determine their content. Caffeine was the methylxanthine that was most found in the samples investigated. Instant coffees gave the highest caffeine percentage (18\u201344 mg\u00b7g\u22121). Green and scented teas were found to have a caffeine dry-weight content (8\u201326 mg\u00b7g\u22121) equivalent to ground coffees (13\u201323 mg\u00b7g\u22121), but black and pu-erh teas (18\u201330 mg\u00b7g\u22121) had a higher caffeine content. The evaluation of the most conventional methods for preparing espresso coffees showed that an espresso contains between 88\u2013116 mg of caffeine. In the case of tea beverages, the amount of caffeine present was 2\u20133 times smaller than in espresso coffees. Energy drinks showed a similar caffeine content (80\u2013106 mg) as espresso coffees. Chocolates had the lowest caffeine content. It has been found that none of the foods evaluated reach the recommended daily intake limit of 400 mg of caffeine with a single dose. This limit can be reached with 4\u20135 doses in the case of coffees and energy drinks. In the case of chocolates, the methylxanthine compound detected at large levels was theobromine, with amounts ranging from 4 to 10 mg\u00b7g\u22121 for dark chocolates.<\/jats:p>","DOI":"10.3390\/foods6120109","type":"journal-article","created":{"date-parts":[[2017,12,4]],"date-time":"2017-12-04T11:16:38Z","timestamp":1512386198000},"page":"109","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Methylxanthine Content in Commonly Consumed Foods in Spain and Determination of Its Intake during Consumption"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4139-7273","authenticated-orcid":false,"given":"Juan","family":"Sanchez","sequence":"first","affiliation":[{"name":"Chemistry Department, University of Girona, 17003-Girona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/0265203021000007840","article-title":"Effects of caffeine on human health","volume":"20","author":"Nawrot","year":"2003","journal-title":"Food Addit. 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