Investigating carotenoid loss after drying and storage of

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6. Effect of pre-treatment
after 1 month (31 days); 2 months (62 days); 4 months (125 days) and 6 months (187
days). Temperature and humidity were recorded every four hour using Tinytalk
temperature/humidity sensors (RS Components Ltd, UK) during storage.
6.2.5 Carotenoid analysis
Carotenoid analysis was undertaken both in the UK (for dried samples only) and in
Uganda (for dried samples that have been stored). In all cases, collected samples were
stored in the freezer in Uganda (-20°C). Dried sweet potato chips were transported in
cooler bag to the UK and stored in the freezer upon arrival. These were milled before
analysis using a Laboratory mill 3600 (position 3) (at NRI, UK). Dried and stored sweet
potato chips were milled using a Glen Mills, Clifton, model C/11/1 (position 17) (at
NARL, Uganda) (Chapter 2 section 2.3.1). In Uganda or in the UK, total carotenoid
extraction and analysis were carried out following method by Rodriguez-Amaya and
Kimura (2004) (Chapter 2 section 2.3.4). For quicker partitioning 10% NaCl solution
(50ml) replaced deionised water. Total carotenoid content was determined using a
Genesys 10UV /UV-visible spectrophotometer (Uganda) or a Diode Array detector
spectrophotometer (Hewlett Packard HP8452A) (UK) at 450 nm.
6.2.6 Statistical analysis
Normality was assessed for all the samples (p