I start my notes with the latest project before I went to German to continue my study. The project held by collaboration between Assessment Institutes for Agricultural Technology of Papua and Local Government. The project idea is to improve add value of sweet potato in Papua. Papua has many accession of sweet potato, and sweet potato usually eat as raw material. Sweet potato processing to flour and then transform to cookies are expected improve the utilities. Cookies and snack usually made from wheat flour base, and we can reduce it with substitute by sweet potato flour. Figure below shown how to make sweet potato flour.
You can use dryer i.e. oven or sun drying to make sweet potato flour. The differences dryer method that you choose will impact to the flour quality. Oven dryer will last for a few hours, depend on temperature and layer thickness. You do not use high temperature, or the flour will get burn taste and dark color. I do not have the exactly data for dryer in this project, but temperature set up 60-70 °C will be enough, it will last for approximately 12 hours. You can increase the temperature set up until 95 °C but it depend how fast you want to make flour and how thick is your batch. Sun dryer will last about 3-4 days if the sun shine is good, and for extreme hot weather in summer time, 2 days sun drying will be enough. Sweet potato flour yield I count about 30% for both sun drying and oven drying. Sweet potato flour dried by sun drying resulted more slight brown than oven drying.
Location: Sentani, Papua, Indonesia
Time: November-December 2011