Strategies for agricultural odor control

Amelioration of poultry manure odor intensity and unpleasantness by diet supplementation with copper chlorophyllin complex (0.1% and 0.01%, wt/wt) and two different types of chitosan (3%, wt/wt; 400 cp and 2,000 cp) were evaluated with a sensory panel. Copper chlorophyllin complex (0.1%, wt/wt) and chitosan 2,000 cp (3%, wt/wt) were most effective compounds at decreasing both odor intensity and unpleasantness. Raising pH resulted in greater amounts of ammonia in sample headspace, while lowering pH resulted in greater amounts of short-chained fatty acids in sample headspace.; The odor absorption capacities of novel and commercial substances were evaluated with static and dynamic headspace extraction techniques. Analytical measurement was conducted with gas chromatography and gas chromatography-mass spectrometry. Cedar bedding, chitosan, kenaf, zeolite, and chlorophyll bedding were most effective at absorbing odor compounds as measured with the static headspace method, while silica gel crystals and activated carbon were most effective at absorbing odor compounds as measured with the dynamic headspace method. In the static headspace method, silica gel crystals were the least effective at absorbing volatile odor compounds due to saturation with water from the sample mixture.; Different masking agents including commercial materials and extracts prepared in the flavor laboratory from Loblolly pine and Eastern red cedar were tested for amelioration of a model poultry manure odor solution that was evaluated for odor intensity and pleasantness by a sensory panel. The commercial pine extract was the most effective at increasing pleasantness (pleasantness was increased 232%). It followed by the commercial odor neutralizer (increase of 202%), pine extract (increase of 86%), red cedar extract (increase of 82%), a mixture of red cedar and ethyl butyrate (increase of 63%), and ethyl butyrate (increase of 39%). Results of odor intensity showed similar trends as pleasantness.; The odor active compound (α-terpineol) isolated from Loblolly pine extract was identified by gas chromatography-mass selective detector and by gas chromatography-olfactometry as the most odor active compound. The amount of α-terpineol in the extract was 1,573.8 μg/g. This amount was 4,769 times higher than the odor threshold of α-terpineol in water.