The effect of storing Cheddar cheeses at elevated temperatures on proteolysis and flavour development was examined. Cheeses were stored under the following ripening conditions: (1) 8 °C for 32 weeks (control); (2) 15 °C for 8 weeks then 8 °C for 24 weeks; (3) 17-5 °C for 8 weeks then 8 °C for 24 weeks; (4) 20 °C for 8 weeks then 8 °C for 24 weeks; (5) 15 °C for 32 weeks; (6) 17-5 °C for 32 weeks; and (7) 20 °C for 32 weeks. The rates of build up of products of proteolysis and flavour increased in the order of the above treatments and substantial acceleration of ripening was achieved. However, after 32 weeks at 17-5 °C and 16 weeks at 20 °C, cheeses received significantly lower preference scores than the control cheeses (P < 0-05) mainly owing to the development of off flavours. The maximum temperature at which cheeses could be stored for 32 weeks without reduction in quality was 15 °C. Cheeses stored at this temperature for the entire period had levels of products of proteolysis at 12 weeks of age which were similar to those of controls at 32 weeks, and estimations of age at 20 weeks which were similar to those of controls at 32 weeks.

No abstract

No abstract

No abstract

‘Dwarf Parfitt’, an extra-dwarf Cavendish cultivar with resistance to subtropical race 4 Fusarium oxysporum f. sp. cubense (Foc), was gamma irradiated at a dose of 20 Gy and putative mutants were recovered with improved agronomic characteristics. Further screening of putative mutants for improved yield and fruit size, as well as a degree of resistance to fusarium wilt, led to the selection of a line (DPM25) with improved productivity when grown on soils infested with subtropical race 4 Foc. DPM25 was equal to the industry standard, ‘Williams’, in every agronomic trait measured and it consistently showed a lower incidence of fusarium wilt. Further improvement of field resistance to race 4 Foc is needed in DPM25 and further cycles of mutation induction and selection is an option discussed.