Revista Raízes e Amidos Tropicais

10

Authors: Bruna Menegassi, Magali Leonel

Peruvian carrot is a tuber of high production in Brazil with good nutritional value. This work has the purpose to evaluate the technological and nutritional qualities of Peruvian carrot mixed food pasta compared with commercial pastas. The results showed considerable protein level in mixed pasta overcoming the levels obtained in commercial pasta (fresh wheat pasta and cassava pasta) and high level of lipids. The pasta behavior in cooking showed that mixed pasta had high solid loss, low volume increase and yield.

11

Authors: Marcelo Alvares de Oliveira, Viviane Scarmínio Busarca

Yacon is a tropical root used in special markets, mainly in treatments of high cholesterol and diabetes. The roots are eaten “in natura” and taste similar to melon or pear. This plant was introduced in Brazil by the Japanese colony in 1989. This work had the purpose to set up the micropropagation of yacon, through rizophore buds and microstakes, observing the efficacy of asepsis processes and cultivation medium in micropropagation. The mediums utilized were MS with and without the addition of plant growth regulators BAP (6-benzylaminopurine) and NAA (1-naphthaleneacetic acid) and combinations of them. The best kind of asepsis protocol for micropropagation starting from rhizomes was: wash of the rhizomes in water; removal of buds with spatula; disinfection of the buds with benomyl (1,5g.L-1) for 30 minutes; immersion of the buds in alcohol (70%) for 15 seconds; immersion in sodium hypochlorite at 60% v/v during 30 minutes and 3 washes with sterile distilled water. As for micropropagation starting from microstakes, the best protocol was: wash of the microstakes in water; immersion in sodium hypochlorite at 20% v/v during 30 minutes and 3 washes with sterile distilled water. The best medium for micropropagation through rhizome buds was MS added with 2 mg.L-1 of the hormone BAP, which provided 53.33% rate of success. As for microstakes, the best medium for micropropagation was MS added with 0.5 mg.L-1 of BAP, with 40% rate of success. With the utilization of microstakes of the plants developed “in vitro”, the rate of success increase to 76.67%.

14

Authors: Cristiane Fátima Gibertoni, Andressa Milene Parente Nogueira, Waldemar Gastoni Venturini Filho

This work aimed the production of rich fructan syrup from yacon juice cleared in ceramic membranes of ultra and microfiltration. An initial assay with yacon juice whose roots haven’t undergone whitening process has shown that although there had been clarification of the permeate due to tangential filtration, there had been enzymatic dark of root resulting in darker products than the ones from whitened roots. The following assays evaluated the ultra and microfiltration processes using temperatures of 20, 40, 60 and 80°C where it was observed the increase of the permeate flow because of the temperature boost. The 40°C temperature was chosen to continue the work. Transmembrane pressures of 2 and 4 bar were combined with tangential speeds of 2 and 4 m/s showing that the combination of 2 bar pressure and 4 m/s tangential speed resulted in higher permeate flow. The best combinations of temperature, transmembrane pressure and tangential speed were used in tests of retentate concentration (up to 6) with decrease of 31% and 33% in the permeate flow, respectively, in micro and ultrafiltration. Physical-chemical analysis showed total solid accumulation and higher values of total acidity in the retentates of ultra and microfiltration as well as the tendency of lower values of soluble solids, ashes and gross protein of permeate compared with the retentates. On the other hand, ultra and microfiltration did not alter the carbohydrate composition. Permeates from tests of retentate concentration were concentrated up to 74.5-81.0°Brix to obtain syrup with no carbohydrate hydrolysis in this process. Ultra and microfiltration processes were efficient for clarifying the yacon juice and the root whitening process assured the production of rich fructan syrups.