Abstract A three-compartment non-equilibrium gas transport model of ‘Conference’ pear fruit under controlled atmosphere (CA) storage was developed. The model fruit tissue consists of cells, in which the concentrations of respiratory gasses can show gradients, and intercellular space, in which gasses are uniformly distributed. Non-equilibrium of gas concentrations in the cell compartment and intercellular space is assumed. A respiration model based on Michaelis-Menten respiration kinetics without inhibition of respiration by CO2 and incorporating down-regulation of the maximal O2 consumption rate in response to O2 was developed. Conversion of CO2 dissolved in the cell compartment to hydrogen carbonate at a constant pH of 5.0 was included. The model was validated based on experimental data of ‘Conference’ pear fruit during a complete depletion experiment starting from 3.58 mol m−3 O2 and 0.00 mol m−3 CO2. Model predictions match experimental observations well. Gas concentrations in the cell compartment were found to be in equilibrium with the gas concentrations in the intercellular space. The model was used to calculate apparent respiration rates and RQ as if measured in the storage headspace. Apparent values were compared to actual values in the fruit cells and it was found that apparent respiration rates and RQ, calculated based on headspace measurements, underestimated the actual respiration rate and respiratory quotient in the fruit cells. Relative differences of 4 %, 41 % and 41 % were found for the apparent O2 consumption rate, CO2 production rate and RQ, respectively. This affects the design of commercial RQ based DCA systems.

中文翻译：

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在静态呼吸计顶部空间观察到的表观呼吸商低估了梨果实的细胞呼吸商

摘要 建立了气调（CA）贮藏条件下'会议'梨果实的三室非平衡气体输运模型。模型果实组织由呼吸气体浓度呈梯度变化的细胞和气体均匀分布的细胞间隙组成。假设细胞隔室和细胞间隙中的气体浓度不平衡。开发了一种基于 Michaelis-Menten 呼吸动力学的呼吸模型，没有通过 CO2 抑制呼吸，并结合对 O2 响应的最大 O2 消耗率的下调。包括在 5.0 的恒定 pH 值下将溶解在细胞室中的 CO2 转化为碳酸氢盐。在从 3.58 mol m-3 O2 和 0.00 mol m-3 CO2 开始的完全消耗实验期间，基于“会议”梨果实的实验数据验证了该模型。模型预测与实验观察结果很好地匹配。发现细胞隔室中的气体浓度与细胞间隙中的气体浓度平衡。该模型用于计算表观呼吸率和 RQ，就像在存储顶空测量一样。将表观值与果实细胞中的实际值进行比较，发现基于顶空测量计算的表观呼吸率和 RQ 低估了果实细胞中的实际呼吸率和呼吸商。发现表观 O2 消耗率、CO2 生成率和 RQ 的相对差异分别为 4%、41% 和 41%。