Influence of pine and miscanthus biochar on the water activity and moisture sorption isotherms of used broiler litter

John Emerson Linhoss; Maryam Kate Mohammadi-Aragh; Jeffrey Dwayne Evans

doi:10.1016/j.heliyon.2023.e22618

Influence of pine and miscanthus biochar on the water activity and moisture sorption isotherms of used broiler litter

Heliyon. 2023 Nov 20;9(12):e22618. doi: 10.1016/j.heliyon.2023.e22618. eCollection 2023 Dec.

Authors

John Emerson Linhoss¹, Maryam Kate Mohammadi-Aragh², Jeffrey Dwayne Evans³

Affiliations

¹ *Biosystems Engineering, Auburn University, 350 Mell Street, Auburn, AL, 36849, USA.
² Agricultural and Biological Engineering, Mississippi State University, 130 Creelman St., Mississippi State, MS, 39762, USA.
³ USDA-ARS Poultry Research Unit, 606 Spring St., Starkville, MS, 39759, USA.

Abstract

The effect of various inclusion rates of pine biochar (PBC), miscanthus biochar (MCB) and starting moisture contents on the water activity (A_w) of broiler litter/biochar mixtures was examined. Suitable models for the resulting moisture sorption isotherms were also evaluated. For poultry mixed with PBC and MBC, higher starting moisture contents led to increased A_w. A_w generally increased at high inclusion rates of PBC and MBC, which may be explained by the porous nature and general hydrophobicity of BC. Of the five models examined, the exponential rise to maximum was considered to be the most useful due to its accuracy at moisture contents similar to those commonly found in commercial poultry houses (10-30 % wet basis). Accuracy of models was determined using R², mean squared prediction error (MSPE), and mean absolute percent error (MAPE). In general, higher inclusion rates of biochar resulted in less overall prediction accuracy. Results from this paper indicate that several moisture isotherm models can be used to effectively model the relationship between moisture content and A_w in broiler litter and biochar mixtures.

Keywords: Biochar; Isotherm; Litter management; Poultry; Water activity.