Deterioration rates were determined for 15-19% moisture content wheat (Dropia cultivar) stored at constant temperatures. Deterioration rates were determined by measuring germination capacity of the grain and respiration rates of grain. Safe storage time was defined as the time for germination to decrease to 90%. Safe storage times of 19%
...m.c. wheat stored at constant temperatures ranged from 2.5 d at 30 and 35°C to 37 d at 10°C. Deterioration rates of 19% m.c. wheat stored with a step decrease in storage temperatures (35-25, 30-20, 25-20, and 20-15°C) were determined and safe storage times were satisfactorily predicted. Safe storage times of 17% m.c. wheat were 5, 7, and 15 d at 35, 30, and 25°C, respectively. Respiration rates and germination percentages of 15 and 16% m.c. wheat stored at 25°C remained constant for 70 d. The respiration rates of 17-19% m.c. wheat at 25°C increased while the germination percentages decreased with storage time. Germination dropped from 98 to 92-89% when the dry matter losses were about 0.05% and visible mould occurred when the dry matter losses were about 0.1% in 17-19% m.c. wheat.
A laboratory scale no-time frozen dough procedure that approximates Romanian commercial practice has been developed and used to study the effects of ingredients and processing conditions on the bread quality of a straight grade wheat flour during prolonged storage (2 days to 26 weeks). All treatments (baking absorption level, mixing en
...ergy input, mixer type, fermentation and intermediate proof times, removal of oxidant and/or dough strengthening conditioners and partial freeze-thaw cycles) had significant effects (P<0.05) upon bread quality (loaf volume and/or bread score). In general, these effects were more pronounced with extended frozen storage time. High baking absorption, undermixing, bulk fermentation (> 1 h) and removal of oxidant and/or surfactants had the most dramatic effects. Addition of a very strong flour at 30% to strengthen the wheat flour had no significant effect (P>0.05) upon bread quality under optimum conditions.