Author: JUAN CARLOS ARTEAGA ARCOS
To increase the concentration of gelatin in a formulation for pound cake reduced in margarine and partially replaced by canola oil, there is a proportional increase in specific gravity, apparent viscosity and viscoelastic modules, decreasing the size and number of bubbles formed in the batter. In pound cake, there is a proportional decrease in volume and uniformity of the crumb and increase in the firmness, however, the addition of 1.25% of gelatin was the most accepted sensory formulation due to perceived a crumb more consistent and wet, so, the functionality of the gelatin as hydrocolloid, is limited to the final texture of the pound cake, concluding that it may be an alternative to improve the acceptability of a pound cake reduced in margarine, which is also of lower cost.
The use of different hydrocolloids in the partial substitution of margarine by vegetable oils, are evaluated to achieve products with characteristics similar to the traditional product. The objective of this study was to evaluate the effect of the addition of different concentrations of gelatin (0%, 0.75%, 1.25%, and 2.0%) in pound cake formulation reduced in margarine and partially replaced with canola oil. It was determined specific gravity (SG), apparent viscosity, modules of viscoelasticity (G' and G") and number and size of air bubbles in the batter. In the pound cake was determined texture (TPA and sensory evaluation), crumb structure and moisture. By increasing the concentration of gelatin, it was observed a proportional increase of SG, apparent viscosity and elastic and viscous modules, predominating the viscous module with respect to elastic module, and a decrease in the number and size of air bubbles in the batter. In the pound cake, there was a proportional decrease in the volume and uniformity of the crumb, with respect to the size and number of cavities formed, however, sensorially, the most accepted formulation was the addition of 1.25% of gelatin because it perceives a more consistent and moist crumb, therefore, adding gelatin can be an alternative to improve the acceptability of a reduced pancake in margarine, which It's also less expensive.
The static modulus of elasticity (Es) is an important parameter in the analysis of hydraulic concrete structures, changes have been made to the regulation of construction; these changes require minimum values for the Es, so now, in addition to concrete compressive strength (f´c) also Es values should be ensured. A methodology to predict Es is proposed, specifically, the Es were modeled by testing: ultrasonic pulse velocity (UPV), electrical resistivity test (ERT), resonance frequency test (RFT), the Hammer Test Rebound (HTR) and f´c. In order to generate models multiple linear regression technique was used. Cylindrical specimens were prepared in two stages, in the first stage was simulated laboratory conditions in the second stage was simulated conditions of concrete made in situ. All cylinders were subjected to non-destructive and destructive tests at different ages. The research objective is to predict Es from the results of destructive tests (traditionally employed to obtain Es) and nondestructive testing. It was possible to obtain a model whose correlation coefficient indicates the good approximation in the generated predictions.