Effect of Physical and Biological Processing Methods on Chemical Composition, Gas Production Parameters and in vitro Digestibility of Barley Grain

This research was conducted in order to investigate the effect of different physical and biological processing methods on the chemical composition, gas production parameters and in vitro digestibility of barley grain in a completely randomized design (6 treatment and 3 replicates). Treatment were: un processing barley grain (control), Steam-flaked (for 3-5 minutes), yeast treated (Saccharomyces cerevisiae) and steam-flaked, microwaved (850 W for 3 minutes), yeast treated and then microwaved and yeast treated, steam-flaked and then microwaved. The chemical composition of the samples was determined using the standard methods. Gas production test was used to estimate the parameters of gas production of samples. In vitro digestibility of the samples was determined by the batch culture method. Processing methods were effective on chemical composition of treatment. Crude protein was increased by different treatments. The highest amount was observed in yeast treated, steam-flaked and then microwaved (14 percent). Treatments have no effect on neutral detergent fiber of barley grain. Processing decreased gas production of barley grain and lowest amount of these trait was observed in yeast treated, steam-flaked and then microwaved (91.36 ml/200 DM). Treatment has no effect on dry matter and organic matter digestibility. Microbial mass production and its efficiency were increased by all treatments except the microwave treatment and the highest increase was seen in steam-flaked + yeast treatment (183.11 mg/g DM and 0.42 respectively). In general, the results showed that different processing methods can significantly affect the nutritional value of barley grain.