In this study, to develop a crystallisation technique that enables the control of polymorphism under constant temperature, we studied the antisolvent crystallisation of glycine using the gas-liquid interfaces around N2 minute-bubbles as new crystallisation fields where nucleation progresses predominantly. At the minute gas-liquid interfaces, local supersaturation increases due to the accumulation of glycine and antisolvent caused by the negative surface potential of the minute-bubbles. Thus, the nucleation rate is faster and the production of metastable/unstable polymorph is accelerated. At a solution temperature of 303 K, the saturated glycine solution and methanol as an antisolvent were mixed by the two different addition orders as follows: Gly solution/MeOH system, methanol was added into a saturated glycine solution; MeOH/Gly solution system, a saturated glycine solution was added into methanol. While mixing methanol with the saturated glycine solution, N-2 minute-bubbles with an average diameter of 10 mu m were continuously supplied to the mixed solution using a self-supporting bubble generator and a glycine polymorph was produced. In both systems, the generation rate of supersaturation in the bulk solution (rC/CS) was varied in the range of 1.2-71.3 min (1) by controlling the addition rate of methanol or the saturated glycine solution. For comparison, antisolvent crystallisation free of minute-bubbles was performed. Consequently, N-2 minute-bubble injection enabled the selective crystallisation of the metastable alpha-form or unstable beta-form at lower r(C/CS) and decreased the r(C/CS) necessary for alpha-form or beta-form production by approximately 1/2 during antisolvent crystallisation. (C) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.