Traditional sour cassava starch obtained with alterations in the solar drying stage

Daniele Iensen De Oliveira,Luiz Américo Alves Pereira,Ariangelo Hauer Dias,Ivo Mottin Demiate,Paulo Ricardo Los,Aline Alberti,Letícia Demogalski

doi:10.1590/fst.16120

Daniele Iensen De Oliveira, Luiz Américo Alves Pereira + Show 5 more

Open Access

https://doi.org/10.1590/fst.16120

Copy DOI

Abstract

After natural fermentation and solar drying, sour cassava starch acquires expansion property. Traditionally, solar drying occurs without protection, and consequently physical contamination can arise. Thus, the aim of this study was to produce sour cassava starch using a low-cost solar dryer to prevent contamination, whilst retaining the expansion property. The samples were characterized in relation to chemical composition, microscopy and physical contaminants, as well as expansion, thermal, pasting, structural and technological properties. In addition, biscuits were prepared and compared with commercial samples. The solar dryer provided faster drying and lower moisture levels than the control. The specific volumes of the sun-dried products were similar to the control, with minimized contamination. The granules of the starches showed slight erosion on their surface, which was probably due to amylolytic enzymes. X-ray diffraction showed a typical A-type pattern. DSC analysis resulted in higher gelatinization temperatures and enthalpy changes for the sour cassava starch. The pasting properties showed a reduction in the viscosity peak at neutral pH. Although the cassava starch biscuits made with sour cassava starch dried in the solar dryer presented lower expansion levels in relation to the other biscuits produced with commercial sour cassava starch, they had desirable sensory characteristics.

Highlights

Sour cassava starch is an indigenous Brazilian food ingredient that is produced by natural fermentation and sun-drying of cassava starch (Aquino et al, 2015)
The temperature and relative humidity profile from inside the solar dryer is shown in the Figure 2
The solar drying adopted in the present study resulted in reduced time for complete drying without blocking desirable UV-radiation, whilst minimizing contamination by insect fragments and soil/sand particles

Summary

Introduction

Sour cassava starch (polvilho azedo) is an indigenous Brazilian food ingredient that is produced by natural fermentation and sun-drying of cassava starch (Aquino et al, 2015). It is a traditional and valued ingredient for its high sensory quality (expansion at baking, taste/odor), but the artisanal production without quality control is prompting to market change, which prefer cheaper chemically modified substitutes (Aquino et al, 2016). Sun-drying fermented cassava starch is performed without any protection against physical contamination, which compromises its quality. Standardization is urgently required in order to increase the market for sour cassava starch (Aquino et al, 2016)

Objectives

Methods

Results

Conclusion