Abstract Common off-flavor compounds including geosmin (GSM) bioaccumulate in fish cultured in recirculating aquaculture systems (RAS) resulting in unpalatable fillets that are objectional to consumers. Most RAS facilities relocate fish from grow-out tanks to separate depuration systems with increased water flushing to remediate pre-harvest off-flavors, but certain aspects of this procedure have not been optimized including characterization of water exchange rates that effectively diminish off-flavor. To this end, a study was carried out to evaluate the effects of flushing rate and associated depuration system hydraulic retention time (HRT) on GSM removal from Atlantic salmon Salmo salar originally produced in a semi-commercial scale freshwater RAS. Twenty-six fish (5−7 kg each) were stocked into twelve replicate depuration systems operated with system HRTs of 2.4, 4.6, and 11.3-h, respectively (N = 4). Geosmin was assessed at intervals in system water and fish flesh over a 10-day feed withholding period. Waterborne GSM concentration was affected by flushing rate and associated system HRT (P

中文翻译：

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净化系统冲洗速度影响从市场规模的大西洋鲑鱼 Salmo salar 中去除土臭素

摘要 包括土臭素 (GSM) 在内的常见异味化合物会在循环水产养殖系统 (RAS) 中养殖的鱼类中生物蓄积，导致消费者不喜欢的鱼片难吃。大多数 RAS 设施将鱼从养成池转移到单独的净化系统，增加水冲洗以修复收获前的异味，但该程序的某些方面尚未优化，包括有效减少异味的水交换率的表征。为此，开展了一项研究，以评估冲洗速率和相关净化系统水力停留时间 (HRT) 对从最初在半商业规模淡水 RAS 中生产的大西洋鲑鱼中去除 GSM 的影响。将 26 条鱼（每条 5-7 公斤）放入十二个重复净化系统，系统 HRT 分别为 2.4、4.6 和 11.3 小时（N = 4）。在 10 天的饲料暂停期内，每隔一段时间对系统水和鱼肉中的土臭素进行评估。水性 GSM 浓度受冲洗速度和相关系统 HRT (P