What is the difference between Lycopene versus Fresh Tomato Color Index (FTCI)
Lycopene Index and Fresh Tomato Color Index are very different and have specific uses.
Fresh Tomato Color Index is fixed for all users.
Fresh Tomato Color Index FTCI = (100((21.6/L) - (7.5*b/(L*a))) using the Hunter L, a, b color scale for C/2 conditions.
There is no universal "Lycopene Index". While there are correlations cited in literature, they are all dependent on the method of sample preparation and measurement which varies from publication to publication. Effectively each user establishes their own "Lycopene Index".
CMR3098 offers the following equation for the calculation of Lycopene Index.
Lycopene (mg/kg) = (gain*a/b ratio) + offset
gain is user-editable = 0.0039 as default
offset is user-editable = 0.3319 as default
a/b ratio is determined from Hunter a and b color values, fixed for C/2 conditions.
The user is expected to determine their own gain and offset if they want to more closely HLPC or spectrophotometric transmission measurements.