Obtaining and characterization of vegetable fibers for the nutritional improvement of gummy candies: doctoral thesis progress

Abstract

Considering that being overweight is a consequence of malnutrition, that affects all the countries in this region and has also a global reach, it is important to maintain a good diet by eating healthy and low-calorie foods.
Consequently, researchs in the food area are aimed to obtain ingredients with functional characteristics from natural sources, to incorporate them into foods that promote a balanced and nutritious diet, and therefore, prevent chronic diseases. One of these functional components is dietary fiber, which is found in a wide variety of vegetables such as cassava, sweet potatoes, and gingers, grown in the Northeast of Argentina. Consequently, this doctoral thesis plan propouses the reformulation of gummies type candies to improve them nutritionally with the addition of fiber extracted from regional vegetables. It will also act as a structural agent due to the replace the sugars present in the formulation with non-caloric sweeteners to reduce the caloric intake.
In this work, the progress made from the plan will be presented, which began in mid-2019 and continues until today. Firstly, the sweet potato dietary fiber extraction test was performed by using a traditional chemical method with ethanol at 85% (v / v) as solvent, and the yield was determined. Process parameters such as pre-treatment conditions, extraction and drying temperatures, ratio, drying time, and sieve size were defined, resulting in yields of 10% approximately. In addition, determinations of the bioactive components were carried out: total carotenoids and antioxidant capacity of the raw material’s sweet potato, ginger, and cassava, to characterize them. In both cases, spectrophotometric methods were used, and total carotenoid content values of 14.27 ± 0.55 µgβ-carotene/gsample were obtained for ginger, and of 12.66 ± 1.43 and 1.35 ± 0.06 µgβ-carotene/gsample, for sweet potato and cassava. A similar behavior occurred in the case of antioxidant capacity where ginger was 90% and 50% higher compared to cassava and sweet potato, respectively.
In this way, the performance of the chemical extraction of fiber from sweet potatoes was determined, and it was observed that ginger was the plant material with the highest content of bioactive compounds, which makes it a potentially usable ingredient to achieve the nutritional improvement of foods.