CASSAVA LANDRACES: MOLECULAR CHARACTERIZATION, CULINARY QUALITY AND POSTHARVEST CONSERVATION OF MINIMALLY PROCESSED ROOTS
Culinary characterization, genetic diversity, Manihot esculenta.
Cassava (Manihot esculenta Crantz) is cultivated in several brazilian regions, it is one of the crops of greatest socioeconomic importance for the country. It has a wide possibility of use, such as in the manufacture of food products for human and animal consumption. This study aimed to carry out the molecular, phenotypic and culinary characterization of roots of 15 of cassava landraces cultivated in the north of Mato Grosso state, Brazil. For the molecular characterization, young leaves were used for DNA extraction and 15 molecular markers of the ISSR type. The phenotypic characterization of the roots was performed by evaluating the texture of the epidermis, skin color, cortex color and pulp color. Culinary quality was determined by analyzing the facility of peeling the roots, the cooking time, the pre and post cooking weight variation and the cooked mass pattern of roots in natura and stored in the freezer in packages with and without vacuum for 30, 60 and 90 days. Using the ISSR markers, it was possible to confirm the existing genetic diversity among the 15 evaluated cassava landraces. This diversity was revealed by the percentage of polymorphism (72.94%) and by the formation of groups with 15 landraces in the UPGMA, Tocher and Structure cluster analyses. The landraces did not form groups by sample location, which may be associated with the exchange of cassava stems among farmers in the municipalities of MT, an important activity for the maintenance of cassava genetic resources. 73.3% of the evaluated landraces have rough root epidermis texture, 53.3% have dark brown skin color and 73.3% have white or cream cortex color and 60% have white in natura pulp color. The cooking time in a conventional pan ranged from 17 to 35 minutes and the pattern of cooked pasta varied between 5 and 10, while in the pressure cooker all landraces were cooked after 10 minutes, with a pattern of cooked pasta ranging from 4 to 9 minutes. Regarding the evaluation of frozen roots, a better pattern of cooked pasta was observed in roots stored in vacuum packaging. Considering the cooking time and the pattern of cooked pasta, four landraces stood out as promising for fresh consumption (Cascatinha, Folha Roxa, Branca and Amarelinha), and after freezing the landraces: Capelari, Amarelinha, Folha Roxa and Cascatinha stand out.