Feed mixtures containing different amounts of untreated and NaOH - treated wheat strau were fed to young bulls. The wheat strau was treated with 4.5 kg NaOH on 100 kg straw (dry matter basis). For the feed mixtures containing up to 40% (5, 20, 40%) untreated and NaOH - treated straw coefficients of digestibility were not significantly different. The feed mixtures containing above 40% NaOH - treated straw (50%) showed the improvement of digestibility by 4 to 7 units.
Preliminary tests of organic product dehydration process under negative pressure were carried out. Artificially moistened field bean seeds, dehydrated under 20°C, 25°C, 30°C, and 35°C were used in the pilot study series. The tests were run under 55 kPa pressure, 10 kPa, and at atmospheric pressure. Sample weight loss, temperature, and pressure were recorded during the course of drying - from initial water content of .28 kg/kg d.m. to the final .12 kg/kg d.m. - under the pressure of 55 kPa; running the process at 10 kPa resulted in dehydration time nearly four times shorter than that necessary to obtain the same water content under the atmospheric pressure. It was found that - under the same temperatures - the rate of dehydration is greater for lower dehydration chamber pressures. It was also found that - under the same pressures - the rate of dehydration is greater for higher temperatures in negative pressure chamber.