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Osmotic dehydration (OD) is a nonthermal technology for preserving and processing fruit (Junqueira et al., 2021; Dermesonlouoglou & Giannakourou, 2018; Kowalska et al., 2017). This method can extend the shelf life of blueberries and produce intermediate-moisture products with better stability (GrajalesLagunes et al., 2019; Yu et al., 2016). The further development of OD in blueberries is hindered by osmotic agents and efficiency (Yu et al., 2016; Ciurzyńska et al., 2016; Kucner et al., 2013; Ketata et al., 2013). Sucrose is one of the most commonly used osmotic agents in the OD of blueberries (Yadav & Singh, 2014; Vega-Gálvez et al., 2012). However, the use of sucrose to dehydrate fruits will increase the sugar content and the calorific value of the final products, which are important because glycemic index and calorific intake are dietary concerns among consumers, particularly those who are diabetics (Shi et al., 2017). In recent studies, many researchers have tried a variety of low sugar solutions, including polyols and low-sugar fruit juice, to reduce the calorie content and glycemic index of dehydrated products (Cichowska et al., 2018; Akharume et al., 2016). The high viscosities of sucrose, polyols and low-sugar fruit juice solution limits their applications in the OD of blueberries at low temperature (<25 °C), and many physicals methods, such as vibration and stirring, cannot improve the efficiency (Dimakopoulou-Papazoglou & Katsanidis, 2019; Telis et al., 2004; Tonon et al., 2007). Higher temperature can improve the OD efficiency, but high temperature is harmful to the anthocyanins and phenols in blueberries (Allan-Wojtas et al., 2001; Yu Y et al., 2017). Anthocyanins are antioxidants and important solutes in a healthier product (Grajales-Lagunes et al., 2019). To improve the efficiency of OD for blueberries, the use of a ternary solution can increase the osmotic pressure gradient of the solution without reaching the saturation limit of the OD solute (Dimakopoulou-Papazoglou & Katsanidis, 2019; Telis et al., 2004; Derossi et al., 2015). Sodium chloride (NaCl) is a common OD solute in ternary solutions (Telis et al., 2004; Tonon et al., 2007; Derossi et al., 2015). However, excessive intake of sodium in the human-body can cause high blood pressure and cardiovascular disease (Rodrigues et al., 2016; Silva et al., 2014). In studies of the OD of fruits and vegetables, calcium chloride (CaCl2) is a new salt substitute (Silva et al., 2014; Jesus Junqueira et al., 2017). Compared with NaCl, CaCl2 has lower effects on the physio-chemical and sensory properties of dehydrated products and can also avoid the negative effects of NaCl (Jesus Junqueira et al., 2017). In addition, the skin of blueberries is a determinant factor that hinders mass transfer during the OD process (Kucner et al., 2013; Ketata et al., 2013). Freezing treatment is a low-cost and ordinary processing technology Osmotic dehydration kinetics of fresh and frozen blueberries considering volume shrinkage in a novel ternary solution