Project Number: 6645-41000-005-12
Project Type: Reimbursable

Start Date: Apr 28, 2008
End Date: Dec 31, 2008

Objective:
The project aims to: 1) investigate the biochemical changes in sweetpotato roots during long-term storage, 2) determine the factors causing the inferior quality of fried products processed from stored sweetpotatoes, and 3) develop the processing techniques that will need to be implemented to maintain consistent product quality.

Approach:
Cured sweetpotatoes of commercial cultivars and selected breeding lines will be stored with controlled temperature and relative humidity. Samples will be taken at monthly intervals, up to 12 months, for biochemical analyses including starch, sugars, amylase activities, pectic substances and content of phenolic compounds. The roots will be processed into French fries with varying processing conditions such as washing to reduce the sugar levels and blanching with anti-browning agents to reduce discoloration. Treatments such as calcium addition, pH adjustment and partial dehydration of the strips before frying to improve textural properties of the products will also be evaluated. The results are expected to provide an understanding on the factors that result in inferior quality of the product, and therefore the guidelines to overcome the quality problems associated with the processing of long-term stored sweetpotatoes will be developed.