Investigating carotenoid loss after drying and storage of

in Chapter 2 section 2.3.3.
5.2.7. Dry matter determination and colour measurement
120
5. Mozambican field study
Dry matter determination and colour measurement are described in Chapter 2 section
2.2.4 and 2.3.2 respectively.
5.2.8. SPME/GC/MS analysis
The SPME system is described in Chapter 2 section 2.3.5. Operating conditions used
were as follows: splitless injection (4 min); injection temperature, 220°C; initial oven
temperature 40°C (held for 5 min), increased by 3°C.min -1 to 250°C and held at this
temperature for 15 min. Volatile compounds were identified using the Wiley Mass
Spectral Library and a standard curve using β-ionone (purity "97%; predominantly
trans, Sigma-Aldrich, France) as internal standard (see details in Chapter 8). In this
chapter, which is a preliminary trial with the measurement of volatile compounds, only
peak areas for total volatiles are reported.
5.2.9. Statistical analyses and calculation of carotenoid degradation rates
Statistical analyses (ANOVA and Pearson test) were described in Chapter 2 section
2.3.6.
Carotenoid degradation rate (k) was calculated by linear regression following the
formula C = C0
− kt (zero order kinetics) or ln C ln C − kt (first order kinetics)
= 0
where C0 is the total carotenoid content after drying (!g.g -1 ); C the total carotenoid
content at storage time t (!g.g -1 ); k the rate constant (days -1 ) and t the storage time (days)
(see Chapter 1 section 1.4.2).
5.3. RESULTS AND DISCUSSION
5.3.1. Effect of dryer type on carotenoid retention in OFSP chips
Total carotenoid contents for Resisto and MGCL01 varieties after drying that varied by
dryer type and chipping treatment are illustrated in Table 5-1.