Efeito da adição de farinha de linhaça dourada na recristalização do gelo em sherberts diet de uvaia (Eugenia pyriformes Cambess) fortificado com ferro

Abstract

The acceptance and marketing success of a new frozen dessert is due to several factors such as taste, quality, nutritional appeal and texture. In this work, the effect of addition of golden flaxseed flour (Linum usitatissimum) (GFF) in proportions of 0 (T0), 1 (T1), 2 (T2) and 3% (T3), in sherbet diet of uvaia (Eugenia pyriformis Cambess) fortified with iron, has been studied. To simulate the effects of transportation and product display, temperature variation experiments were performed. Treatments were transferred from storage (-25 °C) to a freezer programmed to perform temperature cycles ranging from -20 °C/12h to -10 °C/12h, totaling a temperature variation cycle of 48h in 14 times. Before the start of temperature cycles and every 7 days during 4 weeks the sensory attributes were evaluated by Profile Description Optimized (PDO) and physical parameters characterized such as air entrainment (overrun), instrumental firmness, thermal, microstructural crystallization and ice-recrystallisation by optical microscopy/image analysis, rheological parameters of flow and oscillatory by frequency sweep at -10 °C, with a shear stress of 10 Pascal and a temperature of -10 °C to 5 °C. It was also determined the chemical composition, pH and titratable acidity before the temperature cycles, acceptance and purchase intent of consumers to 14 days of cycling and resistance to melting which was evaluated before and at the end of temperature cycles. The results of ash contents, pH and citric acid were significant and had their values increased with increasing the addition of GFF. Statistically, T3 was the only treatment which was found to be different in relation to the ash content, while T0 and T1 were equal. In relation to citric acid content, T2 and T3 were found to be statistically equivalent. The sensory evaluation by PDO showed decreasing values of grittiness and rising, such as the flavor with the addition levels of GFF. The acceptance and purchase intention was higher for treatments with 0 and 1% GFF. The overrun decreased with the addition of GFF. There was no significant difference in the temperature of nucleation and T3 treatment was statistically different in relation to the melting temperature. Positive and/or negative results were significant for instrumental firmness, initial melt strength, rheological behavior, frequency sweep and temperature, size of ice crystals and recrystallisation. The results of sensory analysis especially regarding the acceptance and purchase intent of sherbets were correspondent and justified by the results of the characterization analyzes of the size and distribution of the ice crystals and the parameters obtained in the rheological analysis. Treatment with 1% GFF obtained the best results according to the analyzes.