###### Abstract
However, even if finished compost is properly maintained, it can become recontaminated from environmental sources, such as wild terrestrial animals and birds, so pathogens such as _Salmonella_ spp. and _E. coli_ can regrow in finished compost or inadequately composted manure [14, 15, 16]. Therefore, detecting the fecal presence in soil or compost would improve efforts to ensure adequate maturation of composts at all stages of the composting process as well as to avoid harvesting in contaminated field areas. Microbial standards for the biological amendments of animal origin such as manure compost provide the biological criteria for applying biological amendments to the field to ensure the safety of produce [17]. These analytical methods for microbial standards, being mostly conventional detection methods relying on cultivation, are time-consuming and material- and labor-intensive [18]. In general, microbial contamination tends to occur in a limited and randomized manner. Thus, before conducting a regulated traditional method, a more effective and rapid on-site method for screening contaminated samples has been requested over the past years [19]. Optical sensing techniques including hyperspectral imaging (HSI), as research tools, have gained increasing attention as tools for the rapid detection of anomalies in food products in recent years [20, 21, 22, 23, 24]. Hyperspectral imaging, which combines imaging and spectroscopic technology, can rapidly acquire spectral information at each pixel in an image in a non-invasive and non-destructive manner, and thus has the potential for use in screening products for contaminants based on unique spectral features across the sample image [25]. Originally, hyperspectral imaging was developed for remote sensing applications, but it has now been applied in a number of fields including food safety and quality, pharmaceuticals and material science [26]. In particular, regarding the detection of animal feces, the investigation of optimal fluorescence excitation and emission bands found that fluorescence emissions with excitation at 410 to 420 nm from naturally occurring chlorophyll \(a\) and its metabolites were good markers for fecal contamination [27]. Moreover, hyperspectral fluorescence imaging has been applied to detect bovine fecal contamination on produce for biological safety, and various methods of image processing, spectral pretreatment, and modeling have been developed and refined to improve resolution and lower detection limits. For example, hyperspectral fluorescence imaging showed great potential for detecting cow fecal contamination spots on apples [28, 29, 30], cantaloupes [31] and tomatoes [32] and was found to be more sensitive than reflectance imaging. Moreover, recent studies include hyperspectral fluorescence imaging on green leaves with high concentrations of chlorophyll \(a\), such as romaine lettuce and baby spinach, and a two-band ratio method was determined for distinguishing fecal contamination spots on leafy greens because the emission peaks from bovine fecal matter (near 670 nm) and green plant leaves (near 685 nm) occur in close proximity to the same visible spectral region [33; 34; 35]. This rapid screening method using fluorescence imaging can potentially be used in situ to detect fecal matter in soils and manure compost samples and to enhance the efficacies of soil and compost sampling operations. In this research, hyperspectral fluorescence imaging techniques were investigated (1) to characterize feces samples from bovine, swine, poultry, and sheep species; and (2) to determine feasibilities for detecting and identifying the presence of animal feces and the species origin of the feces, respectively, on or in soil-feces mixtures. In addition, the imaging technique was evaluated for the potential determination of manure compost maturity. The aim of this investigation was to develop field portable imaging devices for in situ screening of soil and compost samples for animal fecal matter.