Revista Raízes e Amidos Tropicais

8

Authors: Vitor José Miranda das Neves, Fernando Broetto, Jesé Abramo Marchese

The sub-products of the industrialization of the cassava are parts of the proper plant, generated in function of the industrial process used for its improvement. The crueira is constituted by pieces of roots and peel, separate for sieves before the oven, in the processing of the manioc flour. In this work, some experiments were conduced aiming to induce a hydrolysis of a crueira suspension for release sugars in a 100 L reactor under agitation and controlled temperature. After hydrolyses, the ºBrix values were evaluated and the qualitative analysis of sugars was performed by HPLC. The fermentation process was conduced in a stainless steel reactor during 48 h under temperature control by 35ºC. The wine was distilled in a 2,20 m of length glass column (Bo-silicate), with feeder installed in the middle of the column and a condenser in the superior extremity. The work temperature of the column head was maintained among 80-82ºC, being the produced ethanol analyzed as the ethanol percentage in HPLC, alcoholic content (ºGL) and its isotopic discrimination. The obtained results showed a concentration of 19ºBrix in the hydrolyzed with 98,35% of glucose, 1,20% of maltotriose and 0,45% of dextrin. The obtained ethanol presented 88ºGL and after distillation 96ºGL and 82,2% of ethanol. The isotopic discrimination confirmed to be the obtained ethanol originated from a typical C3 plant. The income of the process was of 65,8%, what confirms the crueira as potential material for the ethanol production through enzymatic hydrolyses.

11

Authors: Ana Carolina da Costa Lara, Silvio José Bicudo, Elizeu Luiz Brachtvogel, Magno Luiz de Abreu, Felipe Curcelli

The cassava (Manihot esculenta Crantz) is an important tropical culture, and constitutes the alimentary base of about 500 million people of Africa, Asia and Latin America. The domesticação of the cassava plant occurred together with the old peoples, through practical of election carried through for the man, in its itinerante culture and for the proper natural election. The existing cassava genotypes in the collections and banks of germoplasma of the world present sufficient variability degree, and supply to the melhoristas most of the characters of economic interest. The programs of genetic improvement of the cassava aim at to get materials with resistance the main illnesses caused for fungos as Fusarium spp. e Phytophthora sp., with bigger texts of protein, cianogênico potential minor, beyond better culinárias qualities. Advances come being reached in the programs of conventional improvement, and more recent research shows the potential of the genetic improvement through the biotechnology in cassava genotypes.

15

Authors: Karina Fernandes de Camargo, Magali Leonel, Martha Maria Mischan

In this work it was analyzed influence of the barrel extrusion temperature (39,5 to 90,5 ºC), humidity (12,5 to 19.5 %) and fiber content (0 to 8 %) on the viscoamylography properties of mixtures of sour starch and cassava bagasse. The processing was carried through in a single screw extruder (IMBRA RX). It was used the central composite design to evaluate the effect of the independent variables on viscosity characteristics. The results showed that the extrusion temperature followed for the humidity of the mixes and fibre percentage had significant influence on the mistures viscosity properties, occurring to increase of initial viscosity and reduction of the peak, final viscosity and the retrogradation. In the intermediate conditions of the extrusion parameters it was possible to obtain mistures with desirable characteristics for use in instantaneous products with considerable fiber content.

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.

8

Authors: Fábio Iachel da Silva, Cláudio Cabello, Aura Cristina Bruder Pereira

The objective of his study was to adapt a methodology for molecule separation chain size, and to determine the molecular chain sizes of cassava starches. Results showed that gel permeation under low pressure was a suitable methodology for separating samples according to molecular chain size.

10

Authors: Magali Leonel, Silene B. S. Sarmento, Tainara B. Ferrari

Part of Brazil’s ginger crop is below export quality. The aim of this study was to increase the value of these remaining rhizomes by evaluating it as a raw material for the starch industry. Ginger rhizomes were chemically characterized and the starch obtained was evaluated for chemical composition, amylase content, granule shape and size, and pasting properties. Process yield was calculated from the mass balance. The ginger rhizomes had high moisture content (84.37%) and considerable starch content (11.42g/100g). The starch contained 20.38% amylase. The post starch extraction residue had high fiber content (3.8g/100g), which could be used as a fiber rich product. The mass balance showed that 69.7% of initial starch content was extracted during the process with a 7.2% yield. Starch granules were oval and circular in shape and diameters varied from 9.6 to 26.42m. Pasting temperature was 91.1ºC with high heat stability under mechanical agitation and low retrogradation tendency.

10

Authors: Walison Fábio Rogério, Magali Leonel, Marcelo Alvares de Oliveira

During agricultural production part of the roots and tubers are discarded because they are not of commercial quality. A possible way of adding value would be producing fried chips. The aim of this work was to evaluate quality characteristics of chips made from tropical tubers. Roots and rhizomes were characterized for chemical composition and chips for moisture content, lipids, calories, and texture. Results showed that taro (Colocasia esculenta) chips absorbed more fat (42.92g/100g), followed by sweet potato (Ipomoea batatas) (33.56g/100g), peruvian carrot (Arracacia xanthorrhiza) (33.95g/100g), and cassava (Manihot esculenta) chips (33.10g/100g). Yam (Dioscorea alata) chips had the least fat absorption (26.38g/100g). In relation to crisp texture, sweet potato chips had the least crunchy (240.2 g.f), and cassava chips the most crunchy texture (391.4 g.f). Sweet potato chips browned while frying. Taro chips were the highest in calories (611.26Kcal/100g); sweet potatoes had 581.76Kcal/100g, peruvian carrots 558.17Kcal/100g and cassava 556.35Kcal/100g, with the lowest in yam products (524.41Kcal/100g), showing a relationship with the fat absorption after frying. Results were interesting for yam chips due to low fat absorption, less calories, and texture.

20

Authors: Magali Leonel, Marcelo Alvares de Oliveira, Jaime Duarte Filho

The search for new starches to meet the demands of the consumer market means increased research into natural starches. The food industries are the largest starch consumers; however, it is also used in many industrial processes such as chemical and textile industries. This study aims to show the importance of tropical plants as potential sources of starch raw materials. Cultivation aspects were studied for different starch sources from Brazil and around the world, performing tuber and rhizome chemical composition analysis, agronomic evaluations, and yield assesments.