Abstract:

Starch is a glucose homoglycan that constitutes the main source of energy storage in plants. It is made up of two components: amylose and amylopectin, which are also differentiated by the bonds they present. Amylose contains α-(1,4) bonds forming a linear structure that acquires a helical conformation within the starch granule. On the other hand, amylopectin has α-(1,4) and α-(1,6) bonds and is the branched constituent. In addition to its nutritional importance, providing between 40 and 80% of the calories ingested in the human diet (Wang et al., 2022), it also has technological importance in the food industry as it is an additive used in a large number of processed foods due to their thickening and gelling properties as well as their ability to stabilize and improve texture. Starch, in its native form or subjected to modifications, is used in products as diverse as creams, yogurts, sausages, and bakery products.

University students studying Food Chemistry must be able to identify and quantify the main components within food matrices, using different analytical techniques. The experimental courses or "Food Laboratories" of the curriculum focus on the development of these capabilities, as they allow students to consolidate and apply theoretical concepts while developing basic competencies and skills for their training, such as the use of equipment and instruments and the ability to solve problems. However, given the occurrence of situations that limit the access to laboratory practices, it is important to develop alternatives based in home-learning activities. This work presents the implementation of a distance experimental didactic sequence that was applied to students of Food Chemistry coursing the Food Laboratory I, in which, based on iodometric techniques, they could quantify the starch content in food, using a self-designed and self-applied calibration curve, with a mobile phone application as a spectrophotometer. When implementing the sequence, a significant improvement was observed in the acquisition of knowledge of the students when comparing the notes of partial evaluations with those who only have theoretical activities during the distance course.

Keywords:

Food analysis, starch quantification, iodometry, distance learning/home laboratory.