Mass transfer during the vacuum frying of Malanga slices (Colocasiaesculenta)

Abstract

Abstract-The objective of this research was to study the mass transfer during vacuum frying of Malanga slices (Colocasiaesculenta).Anexperimental design under 3 × 3factorial structure including two factors and four central points was employed. The factors were: Frying time (X 1 ) at 60, 80 and 300 s and Frying temperature(X 2 ) at 110, 130 and 150 °C for a total of 13 experimental units. The optimization process was made using the response surface methodology (RSM) and a second-order regression model was fitted. Finally, the moisture content and oil content was determined to be evaluated in a sensory analysis under a five-point hedonic scale. Malanga slices reached to loss 88.5 % moisture and to increase the oil absorption to 37.02% as the temperature and frying time increased. It can be due to during this process the matrix structure is modified and water flows with high ease of heating media, leaving empty spaces where the oil enters.Keyword-Diffusion coefficient, moisture, oil, sensory analysis I. INTRODUCTION Malanga (Colocasiaesculenta), also known as Taro, is a herbaceous plant of the family of Araceae, an edible root that represents an important source of calories in the regions of the world (4.2 to 4.4) Kcal g -1 dry matter and is favorably compared with other similar products such cassava (1.3 to 1.5) Kcalg -1 dry matter, eating in tropical areas of the world. Besides, it is starch-rich (21.1 to 26.2) % wet basis and has high contents of potassium and magnesium (2251 to 4143) mg*100 g -1 dry and (118 to 219) mg 100g -1 dry matter, respectively.Because of the small sizes of its starch granules, Malanga is highly digestible, used in food preparation. In fact, it has been estimated there is a 30 % of losses during storage of this tuber, and this fraction could resolve hunger problems [1]. To minimize the losses of this tuber, it must be applied a food processing operation to carry from perishable to non-perishable foods. This food matrix has not received attention to improve its potential, which allows its widespread use; most existing studies on Malanga have focused on the characterization of the physicochemical, thermal and microstructural properties of flours, starches and pastes [2].In Colombia is getting started to expand the Malanga consumption, but it is not presented a great demand still by consumers compared with other similar products. However, in other countries, it makes part of the daily diet of people due that is a good source of nutrients and minerals [3]. Like other starchy foods such as potatoes, cassava, plantains, yams; a viable and easy way to increase the Malanga consumption is through of development of fried products. Deep-fat frying is the most old and used to make delicious and crispy foods [4]. This unit operation consists in the immersion of food materials in heated edible oils above the boiling point of the water, producing the quality attributes desired such as color, taste, texture and mouthfeel. Nevertheless, this process is incompatible with recent trends of consumption (e.g ...

Evaluation of the Thermophysical, Sensory, and Microstructural Properties of Colombian Coastal Carimañola Obtained by Atmospheric and Vacuum Frying

“…Oyedeji et al [ 33 ] reported a similar initial moisture content for cassava slices, which was 64%; the authors explained that the moisture content in the product decreased with increasing temperatures, justifying this trend to the fact that as the frying process progressed, the rate of moisture removal was reduced by the elimination of a greater amount of free moisture in the samples. The results observed in this research are similar to those of [ 34 ] in their study on mass transfer during vacuum frying of Malanga discs, who reported that it was evident that moisture decreased as temperature increased. This is evidenced in the study of the properties of sweet potatoes fried under atmospheric conditions, carried out by [ 30 ], where the moisture content of samples fried at 150°C presented higher moisture content than those subjected to temperatures of 170°C and these in turn than those at 190°C.…”