Cashew juice was investigated for its ability to support the growth of Saccharomyces cerevisiae. A characteristic of the juice showed that it contained a mixture of fermentable sugars of which glucose, fructose and sucrose have been identified. Also the concentration of reducing sugars was as high as 15% w/v. Growth studies were carried out in a 7-L batch fermentor at a pH of 5.0 and 30°C with and without nutrient supplementation. The corresponding yields were 0.50 and 0.39 gram cells/gram reducing sugar consumed, respectively. While about 10% of the reducing sugar was consumed in the unsupplemented medium 43% was consumed in the medium with supplementation.

Analysis of the growth of Trichosporon cutaneum on glucose was carried out using the concepts of material and energy regularities. Carbon and available electron balances were used to check the consistency of the measured data and to detect outlying data points. Combined point and interval estimates of the true biomass energetic yield and maintenance coefficient for T. cutaneum were obtained using a multivariate statistical procedure. The analysis shows that T. cutaneum has a higher true biomass energetic yield and a lower maintenance coefficient than Candida utilis, which has been found suitable for SCP production.

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The effect of yeast cell volumetric concentration on the rheological properties of the suspensions was measured in a pipe-flow viscometer at 30°C: at low microbial concentrations the suspensions were Newtonian; however, non-Newtonian behaviour, which could be described by the power-law equation, was observed with suspensions at high microbial volumetric concentrations. At conditions of constant microbial morphology and growth rate, the results also indicated that a relationship could be developed between the power-law constants and the microbial volumetric concentration.