| dc.description.abstract | The study herein was carried out to assess the effect of lactic fermentation and solar
drying in the preservation of kale (Brassica oleraceae var. acephala), which is
commonly known as "sukuma wiki". This is a vegetable conventionally consumed by
all income bracket earners in the country. The approach was to make the vegetable
available all-year-round using a cheap technology, to take advantage of the abundance
of the vegetable during the wet season and compensate for its scarcity in the dry
season.
The study used the conventional method for preservation, namely, blanching
followed by drying as the control. The experimental method was adapted from the
sauerkraut fermentation in cabbages, followed by solar drying. The fermentation
process was monitored In terms of titratable acidity and pH. Other qualitative
determinations of the final products from both the experiment and control were:
moisture content and nutrient content using beta-carotene and ascorbic acid, plus
calcium and iron as indicators. The eating quality was evaluated by sensory tests
using trained panelists. The finished products were also studied for their keeping
quality under different temperatures and humidity combinations in terms of changes
of nutritional indicators, and sensory attributes.
The results showed that the fermentation pattern of cabbage and that of kale were
similar. Final titratable acidity attained in cabbage, however, was 1.58% lactic acid
equivalent compared to 1.2% in kales, which was significantly higher. The final pH of
cabbage stabilized at 3.4, from an initial pH of 6.5, while that of kale stabilized at 4.0,
from an initial pH of 5.6. Crude protein composition of the kale decreased
significantly (p-; 0.05) after fermentation. Total ash also increased significantly after
fermentation, mainly due to addition of sodium chloride.
During the storage period of six months, the fermented samples were able to retain
significantly higher amounts of beta-carotene and ascorbic acid as compared to the
blanched samples at 5% significance level. The chlorophyll levels were, however,
significantly higher in the blanched samples as compared to the fermented samples at
all storage conditions.
On performing sensory evaluation, there were detectable differences in flavour and
general acceptability, with the fermented sample scoring higher.
The results, therefore, showed the possibility of adopting a combination of lactic
fermentation and solar drying as a means of preserving kale and coming up with a
product of superior quality in terms of taste and better nutrient retention capacities. | en |
