Dissertation
Colourants are non-nutritional value applied as food additive such as dye, pigments or
substance that impart colour at permissible level on specific product for improving
sensory properties. Nevertheless, colourants should be used in a manner that does not
compromise the quality and safety of food. During this study, forty samples of unbranded
snacks (10 baobab pulp, 12 ice-lollies, 18 potato-balls) from Dar-es Salaam region were
analysed for artificial colourants. Snacks’ vendors were interviewed using semi-structured
questionnaire (open ended and close ended questions) statistical analysis performed.
Findings showed that various colourants were detected in the products at varying levels
also some of product contain more than one food colourant. Types of the colourants and
corresponding proportion of detected samples were; Tartrazine (95%), Carmoisine (55%),
Sunset yellow (40%), Brilliant blue (27.5%), Ponceau (5%), Acid red (2.5%) and
Quinoline yellow (2.5%). Only Sunset yellow and Brilliant blue are permissible for use in
all the three products and Ponceau in only one product. Samples of baobab pulp (20%)
and ice-lollies (28%) were detected with sunset yellow at levels exceeding maximum
allowable limits. Mean concentration of sunset yellow was significantly higher in baobab
pulp (27.2 ± 6.9 mg/kg) than in ice-lollies (15.4 ± 3.7 mg/kg) and potato-balls (8.3 ± 2.1
mg/kg) (p < 0.05). Mean cconcentration of brilliant blue in baobab pulp (48.6 ±7.5
mg/kg) was significantly higher than 5.75 ± 5.8 mg/kg in ice-lollies (p < 0.01).
Carmoisine, Tartrazine, Quinoline yellow and Acid red have no provision for use in any
of the snacks hence their use was against standards. Majority (87.5%) of the snacks’
processors lacked basic training on food processing and were unaware of appropriate use
of colourants in food and risks associated with abuse. These findings justify for need to
strengthen awareness on appropriate use of artificial colourants in unbranded snacks.
Tanzania Medicines and Medical Devices
Authority