INVESTIGADORES
VERDINI Roxana Andrea
congresos y reuniones científicas
Título:
Effect of whey protein based coating on weight loss, texture and structure of frozen strawberries as affected by freezing rate
Autor/es:
SOAZO, M.; RUBIOLO, A. C.; VERDINI, R. A.
Lugar:
Foz de Iguazú
Reunión:
Congreso; 16th World Congress of Food Science and Technology; 2012
Institución organizadora:
International Union of Food Science and Technology (IUFoST)
Resumen:
Freezing is one of the most effective treatments for extending shelf life and ensure high-quality food
products. However, in the case of frozen fruits some of the potential problems are the high drip loss
after thawing and the significant loss of textural quality. Among its many applications, edible
coatings have been proposed as barriers to minimize moisture loss in frozen foods thus retarding
the rate of package ice formation and dehydration of the product surface. The objective of this
investigation was to study the effect of whey protein based coating on weight loss, firmness and
microstructure of frozen strawberries. For that purpose, aqueous solutions of whey protein
concentrate were prepared with Glycerol, potassium sorbate, beeswax (0, 20 and 40% w/w dry
solid basis) and Tween 80. Emulsions were applied to strawberries using vacuum. A group nondipped
and a group dipped in distilled water were used as controls. After drying at 5 ºC,
strawberries were submitted either to slow or rapid freezing. Both groups of strawberries were
stored at -20 ºC during 30 days and thawed at 5 ºC. Weight loss, textural parameters and
microstructure were analyzed. Results indicated that whey protein based coating were not effective
to decrease weight loss and texture degradation of strawberries regardless of freezing rate.
Microstructural damage decreased with the increase in freezing rate, but coated strawberries were
similar to controls. In conclusion, textural and structural deterioration due to loss of turgor by
dehydration of strawberries could not be attenuated using whey protein based edible coatings.