Mercurial Balm is the second ECM album by Food, the group built around Norwegian drummer and electronics player Thomas Strønen and British saxophonist Iain Ballamy. It follows Quiet Inlet from 2010 and keeps the duo's habit of inviting guests. The result is improvised music that sounds composed, slow-building and layered, where acoustic instruments and electronics are hard to pull apart.

Food began as a quartet in 1998 and was reshaped in 2006 around its two core members, who record almost all their concerts. The material here comes from 2010 and 2011, drawn from the Cheltenham Jazz Festival, the Victoria National Jazz Scene club in Oslo and Rainbow Studio. Austrian guitarist Christian Fennesz plays guitar and electronics on most of the album, and Nils Petter Molvær adds trumpet to one piece. On three studio tracks the Indian slide guitarist and singer Prakash Sontakke, here on ECM for the first time, meets Eivind Aarset's guitar and electronics. Food and Manfred Eicher share the production credit.

The opening Nebular sets the tone with shimmering electronic percussion and slow, brooding tenor saxophone against Fennesz's washes. Astral, at nine minutes the longest track, grows from a carefully built intro of drums and electronics until Ballamy's saxophone rises clear of the textures. The last stretch changes ground. On the title track Sontakke's slide guitar carries the expressive range of Hindustani music into free improvisation, while Aarset, whose own drones often have an Eastern colour, supplies texture rather than lines. "We seek clear and solid ideas," Strønen has said, describing a band that pares things down to what is necessary.

Reviews were mixed. The Ear wrote in 2013 that "it's definitely a whole album rather than a series of pieces", hearing a calm opening that builds to intense drumming and blazing brass. Stef Gijssels of The Free Jazz Collective was cooler, finding that "most tracks have this high level of predictability and lack of dynamics or tension." Ian Mann in The Jazzmann singled out Molvær's fragile trumpet on the ballad Moonpie, paired with Ballamy's soprano.

This is the CD edition, ECM 2269, first released in November 2012.