| dc.description.abstract | Parinari curatellifolia fruit is consumed in its raw state or processed into food products in
rural areas during periods of food shortage. The purpose of the study was to determine the
physico-chemical properties of Parinari curatellifolia fruit, develop food products using pulp
of the fruit as one of the raw materials, and determine the physico-chemical, nutritional and
sensory properties of the products. Fruit used in the research was collected from Harare and
Mahusekwa in Zimbabwe. The mean pulp content of the fruit was 56±5% and makes the fruit
a potential raw material for food processing. Available carbohydrates, whose concentrations
ranged from 73.6±0.5 to 75±1% were the major nutrients in the pulp. Metals in the pulp were
determined by flame atomic absorption spectrophotometry. The major metals obtained were
potassium and calcium whose levels were 1.5±0.1 and 0.5±0.1%, respectively. Viscosity of
Parinari curatellifolia fruit syrup was measured using a Brookfield rotational viscometer.
Viscosity of the syrup decreased with increase in spindle speed and temperature, but
increased with increase in concentration of total solids, Na+
and Ca2+ ions. Cereal-based
products called zvambwa were prepared by heating the syrup and meal of fingermillet.
Zvambwa are traditionally prepared in Mrewa and Mutoko in Zimbabwe. Similar products
were developed from the syrup and meals of pearlmillet, white sorghum, maize and wheat.
The products were developed by cooking the syrup with meals of each of the cereals.
Parinari curatellifolia fruit syrup moulded very well with all meals of the different cereals to
form zvambwa. The major nutrients in the products were available carbohydrates whose
concentrations ranged from 86.94±0.36 to 88.42±0.24%. Products made from maize meal had
the highest content of available carbohydrates. Metals in zvambwa and Parinari curatellifolia
fruit syrup and zvambwa controls were quantified by inductively coupled plasma atomic
emission spectrophotometry. Concentrations of the most abundant metal, K in the different
products ranged from 10843.6±766.9 to 14792.7±439.7 mg/kg while the concentration of the
least abundant metal, Co ranged from 0.13±0.02 to 0.27±0.03mg/kg. Drying experiments for
zvambwa and syrup were conducted in a convective tray dryer. Thin layer drying process of
the syrup and zvambwa were best described by the Modified Page model. The activation
energy obtained for thin layer drying of the syrup (21.0±2.0 kJ/mol) was higher than that for
drying of zvambwa (19.0±2.0 kJ/mol). Sensory evaluation of zvambwa was conducted on the
basis of a 5 point hedonic scale. Zvambwa made from the meal of fingermillet and syrup had
the highest sensory score of 3.333. The high score implies that the fingermillet-based product
was the most preferred form of zvambwa. Reducing sugars in zvambwa and Parinari
curatellifolia fruit syrup were determined by the Dinitro Salicylic acid method. The
concentration of reducing sugars in zvambwa, Parinari curatellifolia fruit syrup and zvambwa
control samples increased with increase in drying temperature. Parinari curatellifolia fruit’s
major nutrients are carbohydrates. By varying conditions influencing viscosity, the flow
behaviour of the syrup may be modified to facilitate preparation of different food products.
Food products can be developed from the fruit syrup and meals of cereals other than meal of
fingermillet. Activation energies of drying of foods are important in the design of food dryers
used in large scale processing of the products. The fruit was successfully used as a raw
material for the development of new products that are sources of energy and essential
minerals. High content of carbohydrates makes zvambwa good sources of energy for
consumers. Potassium plays an osmoregulatory role in the body while cobalt is essential for
synthesis of cobalamin or vitamin B12. The products are potential sources of nutrients
required for normal function of the body. The research provides a guide for sustainable
utilisation of Parinari curatellifolia fruit and small grains in providing food for communities
especially during periods of food shortage | en_ZW |
