Abstract
M.Tech
In South Africa, the gross margins currently achieved on normal pan breads
are minimal. For a number of years manufacturers have been trying to
improve this situation with added ingredients. Probably one of the simplest of
ways to do this is to increase the water absorption, without adversely affecting
the quality of the bread such as loaf volume and shelf life. Another means to
possibly increase profits is to extend the shelf life on bread. The ultimate
would be to supplement the standard formulation with one extra ingredient in
order to enhance all aspects.
White pan bread was supplemented with three different concentration levels
of each lipase, pentosanase, guar gum, к-carrageenan, calcium caseinate
and whey. The effects of the different additives were measured against a
control.
In terms of the water absorption the gums prove to be the best additives,
which is mainly due to their ability to function as water binders. К-carrageenan
was most excellent at both the medium and high concentration levels,
whereas guar gum only performed best at the high concentration level.
Both lipase and pentosanase gave good loaf volumes compared to the rest of
the additives and the control. The positive effect due to pentosanase could
probably be explained by way of two main pathways – oxidative gelation or
spiralling effect of the hydrolysis of water in the dough. Lipase is believed to
strengthen the gluten and therefore ultimately increases loaf volume.
Calcium caseinate was a good anti-staling agent. The mode of action is
probably through its water holding ability, though more work is needed since
the water absorption results did not correlate.
Although к-carrageenan showed increased water absorptions, it also slowed
down mould growth tremendously, possibly since the water is in a “bound”
form and not available for microbial activity.
In the search for one additive to obtain best results for water absorption, loaf
volume and shelf life, it seems that к-carrageenan would be the additive of
choice.