Nitrate Reduction in Canned Apples and Pears Using Calcium Hydrogen Phosphate (CaHPO4)

Background: The aim of this study was to introduce a new and economical method for reduction of nitrate content in canned apples and pears. Methods: The nitrate content was determined before and after treatment with CaHPO4 ranging from 0.01% to 0.1% using spectroscopic method in 2015 in Pharmaceutical Sciences Research Center, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran- Iran. The effect of treatment time at three different time points (30, 60, 90&nbsp;min) was determined. Sensory evaluation was performed using five-point hedonic scales. Results: Nitrate content in fresh fruit is significantly (P<0.05) lower than canned products; this may be explained by the effect of water for washing fruits during processing. The mean value of nitrate in canned apples were significantly (P<0.05) higher compared to the canned pears; this may be related to the type of fruits and its texture and composition. Nitrate content of canned apples and pears were decreased from 233.24&plusmn;24.90 to 128.80&plusmn;0.423 and 195.11&plusmn;20.32 to 118.804&plusmn;0.634 mg/kg, respectively. Different concentration of CaHPO4 did not influence&nbsp;sensory attributes of canned apples while overall acceptance of canned pears decreased only in 0.1% CaHPO4 (P<0.05). The most efficient time for treating by CaHPO4 was 90 min, but the most practical one is recommended 30 min. Addition of CaHPO4 did not change pH of canned samples. Conclusion: Application of CaHPO4 is suggested as a novel, safe and economical method for removal of nitrate in canned products.