11
International Journal of Food Research 2(1): 11-16, 2012
ISSN: 1213-0128
© IJOFR Publications, 2012
Original article
Sensory Evaluation of a Vegetable Yoghurt-like Product from the African
Breadfruit (Treculia africana) Seeds
*Oyeyipo, OO
1
, Iwuji CA
2
and Nworgu UG
3
1, 2
Department of Microbiology, University of Port Harcourt, P.M.B. 5323, Port Harcourt, Nigeria
3
Department of Microbiology, University of Maiduguri, Maiduguri, Nigeria
ABSTRACT: A vegetable yoghurt-like product (ukwa yoghurt) was produced by lactic fermentation of filtered slurry of freshly
dehulled African breadfruit (Treculia africana) seeds. The pH of sample decreased from 5.72±0.06 to 4.47±0.04 during
fermentation time while titratable acidity (expressed as g lactic acid/100g sample) increased from 0.18±0.03 to 0.69±0.02.
Proximate analysis shows that the freshly produced ukwa yoghurt was composed of 89.74±0.4% moisture, 0.93±0.5% ash,
3.95±0.3% protein, 1.76±0.5% fat and 3.62±0.1% carbohydrate. Ukwa yoghurt, Soy yoghurt and a brand of commercially
produced cow’s milk yoghurt (Fan yoghurt) were subjected to sensory evaluation. Overall, ukwa yoghurt compared favourably
(p=0.05) with the soy and cow’s milk yoghurts, 7.5±0.02, 7.3±0.03 and 7.8±0.02, respectively. The shelf life of the product was
72 hours under refrigeration condition (4±2
o
C). The African breadfruit seed could therefore, adequately serve as an alternative
vegetable yoghurt substrate, thus enhancing its utilization.
Key words: Treculia africana, Vegetable yoghurt, Sensory, Utilization
INTRODUCTION
Yoghurt is a semi-solid diary product produced by
lactic fermentation. In the United States, to be named
yoghurt, the product must be made with the following
bacterial species, Streptococcus thermophilus and
Lactobacillus bulgaricus. Usually, these two bacteria
are co-cultured with other lactic acid bacteria such as
Lactobacillus acidophilus and Lactobacillus casei for
their probiotic effect and taste (Okafor, 2007;
Wikipedia, 2008). In most countries, a product may
be called yoghurt if the final product contains live
bacteria. In the United States, non-pasteurized
yoghurt can be sold as “live” or containing “live
active cultures”. A small amount of live yoghurt can
be used to inoculate a new batch of yoghurt. It has
been reported that the quality of commercial yoghurt
is determined by its potential to serve as a starter
culture for home-made yoghurt (Campion, 1995).
Yoghurt is usually produced from cow’s milk but
yoghurt substitute has been produced from soybean
and is commercially available. Among the sources of
vegetable yoghurt, soybean has received very high
research attentions. Soy yoghurt compares favourably
with cow’s milk yoghurt in nutritional composition
(Enwere, 1998) and more research is being designed
to improve the quality of soy products. However,
relatively little attention has been given to bambara
groundnut (Obizoba and Egbuna, 1992), peanut
(Odo, 2001), melon seed (Akubor, 1998) and African
breadfruit (Treculia africana) seed (Oyeyipo, 2011).
African breadfruit (Treculia africana) is a member of
the family moracea; it is indigenous, popularly called
‘Ukwa’ and widely grown in the southern states of
Nigeria for its seeds but under-utilized. The seeds
have been found to contain high quality protein
(17.5%), fat (2.3%), Carbohydrate (73%) (Osabor
and Okafor, 2009). It is thought that the seeds could
be processed into new products, in the same way that
soybeans are used in oriental diets. This study
therefore reports the production and evaluation of a
vegetable yoghurt-like product (ukwa yoghurt) from
the African breadfruit (Treculia africana) seed, and is
the second in the series of steps aimed at enhancing
its utilization.
*Corresponding author: Oyeyipo,OO, Department of
Microbiology, University of Port Harcourt, P.M.B. 5323, Choba,
Port Harcourt, Nigeria. Email: mails4tim1@yahoo.com , Tel:
+2347033395577, +2347065955666