Banca de DEFESA: JHONY WILLIAN VARGAS SOLÓRZANO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : JHONY WILLIAN VARGAS SOLÓRZANO
DATA : 18/12/2019
HORA: 09:00
LOCAL: Planta IV, Embrapa Agroindúsria de Alimentos
TÍTULO:

Development of whole grain expanded extrudates

PALAVRAS-CHAVES:

whole grain, fiber-rich product, grain drying, grain milling, thermomechanical cooking.

PÁGINAS: 105
GRANDE ÁREA: Ciências Agrárias
ÁREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Tecnologia de Alimentos
ESPECIALIDADE: Tecnologia de Produtos de Origem Vegetal
RESUMO:

The consumption of whole grains is associated with healthy eating and encourages to reduce the environmental impact by saving energy from the grain refining industry. People increasingly opt for processed products based on whole grains and preserved by physical methods. In this sense, extrusion cooking is a useful technique to produce preservative-free foods and to increase the range of whole-grain based products. Ready-to-eat extruded snacks produced from whole-grains have hard textures and are darker, which affects consumer sensory acceptance. The main component that affects these attributes is the insoluble fibre deposited in the bran layers. Bran particles are hard to melt and cause physical rupture of the melt at the die exit. A reduction in the size of the bran particles improves the elastic expansion of the extrudates. In this work, the effect of natural fibres on the expansion and textural properties of whole-grain extruded snacks was addressed by size reducing of the bran particles. This was performed using two types of mill (disc and roller), operated in a one-step and without a screening plate, to prevent clogging of the mill sieve. During grinding, the bran and germ tissues are disintegrated and become part of particle surfaces. To improve the fractionation of particles and the particle-size heterogeneity in the feeding material, the grains were dried prior to the grinding process. This step favored the spread of bran and germ tissues in the feeding material. The drying process affected the starch fraction of the grains. The drying and grinding processes influenced on interparticle porosity of feeding material. More porous wholemeal flours were obtained with the roller mill and during its extrusion, generated lower resistance to the work performed by the screw, which was monitored by changes in the motor torque. Considering the lubricating effect of the lipids and fibres present in the whole-grain based feed materials, the water content in the feed was set to levels below 14% (wet basis) in order to produce extruded snacks with good expansion and texture characteristics.

MEMBROS DA BANCA:
Presidente - 105.290.788-13 - JOSÉ LUIS RAMIREZ ASCHERI - UNICAMP
Interno - 2455049 - JOSE LUCENA BARBOSA JUNIOR
Externo à Instituição - SIDNEY PACHECO - EMBRAPA
Externa à Instituição - RENATA TORREZAN - EMBRAPA
Externo à Instituição - JUAREZ VICENTE - UFRRJ