Sensory properties and consumer acceptance of a stirred-type yoghurt Produced from Baobab (Adansonia digitata) pulp during refrigerated storage

Abstract

The baobab (Adansonia digitata L.) tree is widespread throughout the hot and drier regions of tropical Africa. The baobab pulp from the tree is an important source of nutrients in Africa as it is a rich source of amino acids, iron, vitamins C, A and E. In some African countries including Zimbabwe, the pulp is used traditionally to cure various ailments such as dysentery, inflamed gums and as an antidote to poison. Baobab pulp has many food uses and consequently the aim of the current study was to determine the sensory properties of the baobab flavoured yoghurt during storage and consumer acceptance of the yoghurt. A trained panelist evaluated the appearance, consistency on spoon, consistency in mouth, odour, flavour and overall acceptability of the yoghurt on days 1, 7, 14, 21 and 28 of storage. In all the sensory evaluations, plain yoghurt was used as a control. The consumer panelists (n = 150) evaluated taste, texture, colour, smell and aftertaste of the yoghurt. In general, the sensory scores of the baobab flavoured yoghurt and plain yoghurt decreased with storage time. The plain yoghurt had higher appearance scores from day 1 up to day 28 as compared to the baobab flavoured yoghurt and there was a significant difference (p = 0.01) in the scores of the yoghurts. On day 1 the consistency on spoon scores for both the baobab flavoured yoghurt and the plain yoghurt had the same value and from day 2 up to day 28, the plain yoghurt had the highest consistency on spoon scores as compared to the baobab flavoured yoghurt and the difference was significant (p = 0.01). The baobab flavoured yoghurt consistency in mouth scores were lower as compared to the plain yoghurt and the difference in the scores of the products was significant (p = 0.01). The odour and flavour scores of both the baobab flavoured yoghurt and plain yoghurt decreased throughout the storage period and the difference in the scores of the yoghurts was significant (p = 0.05). There was a significant difference (p = 0.05) in the overall acceptability scores of the baobab flavoured yoghurt and the plain yoghurt. Although the baobab flavoured yoghurt scores decreased with time of storage and the yoghurt had an astringent aftertaste, the consumer scores indicated that the baobab flavoured yoghurt was acceptable in terms of taste, texture, colour and smell.

Key words: Baobab, flavoured, yoghurt, sensory properties