Juan Carlos Lucas Aguirre, German Antonio Giraldo Giraldo and Misael Cortés Rodríguez
In order to understand interactions aw vs equilibrium moisture content (EMC) in fortified coconut powder, moisture sorption isotherms were constructed under different storage…
Abstract
Purpose
In order to understand interactions aw vs equilibrium moisture content (EMC) in fortified coconut powder, moisture sorption isotherms were constructed under different storage conditions in order to predict the changes in their physical, chemical and microbiological properties that occur during storage and processing, which are unique to each food.
Design/methodology/approach
For which the moisture sorption isotherms were determined at three different temperatures (15, 25 and 35 °C), in a range of water activity from 0.1 to 0.90. Nine models, namely, the GAB, BET, Oswin, Smith, Halsey, Henderson, Chung and Pfost, Peleg and Caurie equations, were fitted to the sorption data. Various statistical tests were adopted as criteria to evaluate the fit performance of the models.
Findings
Of the models tested, the Peleg model gave the best fit to experimental data (R2 = 0.997; RMSE = 0.276), across the full range of water activities and at different temperatures. Humidity of the monolayer (mo) was found between 2.54 and 2.34%, a fundamental parameter to define the storage and control conditions, given that it is considered the value at which the product is more stable. The net sorption isosteric heat (Qst) increased to maximum and then diminished with increased moisture content (Xw); maximum values were obtained in the Xw interval between 0.48 and 2.87% (db), being between 35.72 and 99.26 kJ/mol, where the maximum value indicates coverage of the strongest bond sites and higher adsorbate-adsorbent interaction.
Originality/value
These results provide reliable experimental data on water absorption isotherms of the CP + FAC important to determine optimal processing, storing and packaging conditions.
Details
Keywords
Diane Rodriguez, Kenneth J. Luterbach and Rocio Espinosa de Gaitan
Special education in Guatemala started in the 1940s with the establishment of schools for the blind. While there is a relatively large population of persons with disabilities, the…
Abstract
Special education in Guatemala started in the 1940s with the establishment of schools for the blind. While there is a relatively large population of persons with disabilities, the country has an insufficient number of educational and rehabilitation programs because the country is very impoverished. Guatemala has enacted a number of disability laws in the 1990s and early 2000s that enable persons with disabilities to participate in educational services to develop their capabilities and to deter discrimination. The government has three categories of disability, namely, physical, sensory, and intellectual. Most of the special education schools and rehabilitation workshops are in the capital city with few programs in rural areas. Many children with special education needs do not attend school. The government offers public service to families of children with disabilities. In the 1980s, the government formed partnerships with United States universities to help develop service plans for students with disabilities as well as train school personnel in effective instructional methods due to a shortage of licensed teachers. While special education is improving it has a long way to go.