The effect of sweeteners and inhibitors on the quality of fresh-cut pear slices after freezing

D. Seglina, I. Krasnova, J. Kviesis, K. Kviesis, I. Gailite
Fresh-pack and frozen pear slices are in demand for various applications, one of them a component in minimally processed products for catering. A number of different techniques are used to maintain the sensory properties and nutritive value of the product. The aim of the study was to investigate the most effective combinations of sweeteners and inhibitors to prevent fruit browning and to maintain quality of frozen pear slices. Pear cultivar LSQUOBelorusskaya PozdnayaRSQUO was used for testing the effectiveness of different inhibitors and their compositions to preserve the quality of the pear slices. Ascorbic acid (1.5%), citric acid (0.5%) and natural cranberry juice (20%) were added to fresh-cut slices for colour stabilization. Calcium chloride (0.5%) and calcium lactate (0.5%) were applied for structure stabilization of the product. 15% sugar and 15% fructose syrups were used as sweeteners to improve the taste of the pear pieces. Samples were frozen and stored at -18±2°C for 3 months. The best combination of the inhibitors was: ascorbic acid 1.5%, citric acid 0.5% and calcium chloride 0.5%. The samples treated with these inhibitors, after defrosting, were found to have the best quality. The vitamin C content of the control pear slices decreased 50-55%, while in slices treated with calcium, citric and ascorbic acid it decreased 37-40%. Total phenol content after refrigeration decreased 56-59% in the control samples and 9.7-14.2% in samples treated with inhibitor compositions. However, the natural inhibitor, cranberry juice, delayed fresh cut fruit browning less than the calcium chloride inhibitor composition. The colour of pear slices treated with cranberry juice after freezing was brighter as well as the content of vitamin C and the total phenols was higher comparing to pieces without treatment.
Seglina, D. , Krasnova, I. , Kviesis, J., Kviesis, K. and Gailite, I. (2018). The effect of sweeteners and inhibitors on the quality of fresh-cut pear slices after freezing. Acta Hortic. 1209, 209-216
DOI: 10.17660/ActaHortic.2018.1209.30
freezing, browning, total phenol, vitamin C, firmness

Acta Horticulturae