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The traditional non-alcoholic beverage in East Africa, togwa, produced from the flour of maize and germinated finger millet (finger millet malt), was investigated. The preparation techniques of togwa observed in the rural villages of East Africa are described, and the temperature and pH profile of togwa during its manufacture are also shown. Maize and finger millet malt should be the source of starch and amylase, respectively. Maize flour slurry was heated once with stirring up to around 80[degrees]C and cooled to about 50[degrees]C, and then finger millet malt flour was added to the warm porridge paste and kept at about 50[degrees]C for 20 min. The consistency of the paste was suddenly reduced by addition of finger millet malt flour and the gel paste changed to viscous liquid, which was kept in a container and incubated at ambient temperature for 15 h. After incubation it became sweet and was ready to drink without removal of any insoluble materials. Changes in the concentration of glucose and lactic acid of togwa during its maturation period were measured using portable devices until 70 h incubation at the rural village of Tanzania in a dry season. Glucose level increased with incubation and reached the threshold value of sweetness; 24 h incubation later, the lactate level increased and pH decreased. The preparation techniques of a traditional alcoholic beverage, pombe, were also investigated in the same rural locality, and the differences and characteristics of both traditional beverages are discussed.

Changes in [alpha]- and [beta]-amylase activities in African finger millet (Eleusine coracana (L) Gaertener) were followed during germination. Germination on a small scale was performed at 15[degrees]C for 1-10 days and at 20, 25 and 30[degrees]C for 1-8 days. [alpha]- and [beta]-Amylase activities in malt crude extracts of germinated finger millet were evaluated spectrophotometrically using chromogenic methods. The highest [alpha]-amylase activity was exhibited in malt flour of finger millet germinated at 15[degrees]C for 9 days and at 20[degrees]C for 6 days, while the highest [beta]-amylase activity was displayed in the malt flour germinated for 5 days at 30[degrees]C. Thermo-stability of these enzymes in malt extracts was also evaluated. Malt extracts incubated at 40 and 50[degrees]C for up to 4 h retained about 84 and 64% of [alpha]-amylase activities, respectively. There was a substantial decrease in [alpha]-amylase activity to more than 90% when malt extracts were incubated at 70 and 90[degrees]C for 40 and 10min, respectively. [beta]-Amylase was completely inactivated when the crude extract was incubated at 70[degrees]C for only 10 min. At pH 5.4, [alpha]-amylase displayed maximum catalytic activity at around 45[degrees]C. Optimum temperature for [beta]-amylase activity at pH 6.0 was between 50 and 55[degrees]C. Activity staining for [alpha]-amylase was also performed and three bands of activity were found in malt extract, each possibly representing an isozyme of [alpha]-amylase from finger millet.

The viscosity of process whey protein (PWP) increases and gelation occurs on adding sodium chloride (NaCl) and incubating PWP at room temperature or temperatures < 25 degrees celsius (C). The gelation is caused by the NaCl-induced aggregation of PWP molecules below 25 degrees C. Heating accelerates gelation but is not absolutely necessary. Viscosity is independent of shear rate. The viscosity increases rapidly with an increase in NaCl concentration.

A simple and fast method involving a microreader system and a 96-well microplate helps determine the turbidity of protein constituents from cheese and acid whey concentrates and analyze the effect of ionic strength and pH on whey protein properties. The method is time-effective and enables rapid measurement of numerous samples simultaneously. Protein samples turn transparent following heat treatment at neutral to alkaline pH values and at reduced ionic strengths, enabling the development of transparent gels under these conditions, using sodium chloride.

Changes in the decomposition of citrinin under watery conditions due to combinations of heating time and temperature were investigated. Citrinin was subjected to heating, thin layer chromatography, high pressure liquid chromatography, ultraviolet spectroscopy and cytotoxicity.The toxicity of citrinin and the products of its decomposition from moist heat cooking were established.

Structural regions of heat-denatured ovalbumin, the globular protein of egg white, were identified using heat-denatured ovalbumin specific monoclonal antibodies as probes. Data analysis revealed five regions within the thermally denatured ovalbumin molecule that showed conformational changes and produced new epitopes that may be hydrophilic and may be found on the molecule's surface.