Browsing by Author "Nannyonga, Stella"

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    Mathematical modelling of color, texture kinetics and sensory attributes characterisation of ripening bananas for waste critical point determination
    (Elsevier: Journal of Food Engineering., 2016-12) Nannyonga, Stella; Bakalis, Serafim; Andrews, James; Mugampoza, Ediriisa; Gkatzionis, Kostas
    It is vital to correlate the instrumental and non-instrumental analyses of food products so as to determine the product waste critical point. Texture and color (instrumental) were determined by a universal testing machine (UTM) and colorimetry respectively to ascertain the kinetics of bananas during ripening. While deterministic, descriptive and ranking sensory tests were employed for sensory attributes characterisation. Seven banana color ripening stages were used for color variation and three temperatures (16, 23 and 30 °C) were used to study the kinetics, L, a, b and ΔE were calculated and axial puncture force, PF determined. Logistic model and first order reaction models were used. The sensory attributes results indicated banana waste critical point from stage 6 while instrumental analyses still indicated a model trend up to stage 7.
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    Organochlorine pesticide residues in skin, flesh and whole carrots (Daucus carota) from markets around Lake Victoria basin, Uganda
    (Taylor & Francis online: International Journal of Environmental Studies., 2013) Nannyonga, Stella; Kiremire, Bernard T.; Ogwok, Patrick; Nyanzi, Steven A.; Sserunjogi, Mohammed L.; Wasswa, John
    Residual concentrations of organochlorine pesticides in vegetables cause concern because of their adverse health effects. Pesticides have been applied in agricultural production and vector control in Uganda. Vegetables may absorb high residual levels of cyclodienes necessitating regular monitoring. Carrots are commonly consumed in Uganda as raw salads or components of different dishes. A gas chromatograph with electron capture detector was used to quantify organochlorine pesticides. Pesticide residues were confirmed by gas chromatography with a mass spectrometer. Trace amounts of 4,4′-dichlorodiphenyltrichloroethane (DDT), 2,4′-DDT, 2,4′-dichlorodiphenylchloroethane (DDE), α- endosulphan, β-endosulphan, α-lindane, γ-lindane and dieldrin were detected in carrots. Levels of organochlorine residues in carrots were below the maximum residue limits considered safe for human consumption by Codex Alimentarius and the European Union Commission.