Evaluation of Odor-Reducing Commercial Products for Animal Waste

Six odor-reducing commercial products were tested for their efficacy in reducing odors from dairy and swine wastes. A sensory panel method was utilized for odor evaluations, in which the panel played an important part. Comparisons between products were made for agitated and unagitated conditions and effect of storage time (three weeks in which experiments were performed). Cotton pieces tied to the mouth of the sample jars were useful in absorbing the odors. Odor-treated jars were observed and evaluated by panel members. The odors were rated on a discrete scale of 0-5, with '0' being no odor and '5' the highest odor level of dairy or swine waste.

The products were analyzed for their effectiveness on dairy and swine wastes separately. The "General Linear Model" was used for data analyses, and all the products were compared for their effectiveness under each waste storage condition and elapsed storage time.

Each product was able to reduce odors. For both dairy and swine wastes, one product stood out and was very effective, whereas another product was less successful. Unagitated storage conditions of swine waste favored the product performance. Unagitated storage conditions were also found to be better for most of the products; only two products were slightly better in effectiveness under agitated storage conditions. The effect of storage time on product-effectiveness for each product for both dairy and swine waste varied. Odor levels from unagitated swine waste was very low in the beginning, but became worse with increasing storage time. Dairy waste in unagitated conditions had slightly higher levels of odors in the beginning, but became a little less with increasing storage time.

Under the conditions of this study, it can be recommended that: 1) P2 has a better chance in reducing odors, 2) in general, unagitated conditions favor the reduction in odor levels, and 3) dairy waste should be treated in the first few days following collection, whereas swine waste should be treated when it is old. Testing of these products in actual field conditions would provide stronger support for these findings.