Investigating the ice crystal morphology in frozen cooked rice based on size, fractal dimension and ANN modeling

• Published in: International journal of refrigeration Vol. 84; pp. 210 - 219
• Main Authors: Kono, Shinji, Tobari, Yuta, Araki, Tetsuya, Sagara, Yasuyuki
• Format: Journal Article
• Language: English
• Published: Paris Elsevier Ltd 01.12.2017; Elsevier Science Ltd
• Subjects: Artificial neural network; Artificial neural networks; Crystal morphology; Crystals; Dimension fractale; Fluorescence; Fractal dimension; Fractal models; Freezing; Frozen cooked rice; Frozen foods; Ice crystal size; Ice crystals; Morphology; Network analysis; Neural networks; Response surface methodology; Rice; Riz cuit congelé; Réseau neuronal artificiel; Size; Storage temperature; Taille des cristaux de glace; Réseau neuronal artificiel; Fractal dimension; Taille des cristaux de glace; Ice crystal size; Artificial neural network; Riz cuit congelé; Frozen cooked rice; Dimension fractale
• ISSN: 0140-7007; 1879-2081
• DOI: 10.1016/j.ijrefrig.2017.08.018

•Characteristic ice crystal morphology was investigated for frozen cooked rice.•Crystal size and fractal dimension were related with freezing and storage conditions.•Both freezing and storage temperatures affected the recrystallization behavior of ice.•ANN modeling provided the method for searching the optimum operating condition. Cooked rice was frozen in an air blast freezer at freezing temperatures of −5, −10, −15, −30 and −45 °C and stored at −5, −10, −15, −30 and −45 °C for up to 90 days. Cross-sectional images were captured using a fluorescence staining method, and then the equivalent diameters and perimeters of ice crystals were determined. The size and fractal dimensions were affected by the relationship between the freezing and storage temperatures. Artificial neural network analysis revealed that the behavior of response surface curves of both sizes and fractal dimensions were similar. The models demonstrated that the storage temperature of −25 °C for 90 days was required for maintaining the size and morphology of ice crystal immediately after freezing at −25 °C. These models would be effective tools for identifying the optimum operating conditions of frozen cooked rice based on the relationship between the ice crystal size and morphology.