# Consumer Characterization of Wet- and Dry-Aged Mutton Flavor Profile Using Check-All-That-Apply
## 1 Introduction  
The Australian wool and sheep meat industry is seeking ways to add value to mutton (mutton in the context of this study refers to sheep meat from female or castrated male sheep older than 2 years). The Australian market only consumes approximately 10% of the mutton it produces, with the majority exported as a commodity product [1; 2]. The eating quality of mutton is a challenge for processors/producers seeking to market mutton products, as it is less tender than lamb and has a stronger flavor, which can be objectionable to some consumers [3; 4; 5; 6]. Holding sheep meat for a period post mortem in an anaerobic environment (weteraging) can improve its eating quality [7]. Wet-ageing is the most common commercial ageing method employed in Australia, which involves packaging whole primal cuts, such as loin or forequarter, under vacuum into plastic [8; 9; 10]. Once packaged, the meat is left in chillers and allowed to age for 5 to 10 days and during this time proteolysis commences, the meat begins to tenderize and favorable flavor changes occur due to the production of free amino acids and other meat flavor compounds and their precursors [11; 12; 13]. Under the anaerobic and acidic conditions characteristic of wet-ageing, most bacteria cannot grow, and LAB (lactobacillus sp.) proliferate, outcompeting potential pathogenic bacteria and making the wet-aged product safe to consume; however, LAB can cause a sour flavor in wet-aged meat [14; 15]. Dry-ageing, on the other hand, is typically used for the production of premium niche beef products and is a potential novel application for sheep meat [16; 17]. Dry-ageing involves hanging unpackaged primals or cuts in temperature and humidity controlled cabinets, usually with auxiliary fans to provide air movement within the cabinet. Ageing periods are often longer for dry-aged products (>21 days) [18; 19]. Proteolysis also occurs during dry-ageing, but tenderization rates and flavor development can differ when compared to the wet-aged equivalent [20; 21; 22]. Dry-ageing is associated with increasedpositive flavor notes such as roasted, beefy, buttery flavors [19; 20; 22]. Several processes may be contributing to these favorable flavor changes; for example, moisture is lost from the meat during dry-ageing and, therefore, flavor compounds are more concentrated at the end of ageing [12], pH differences between wet- and dry-aged meat may affect flavor profiles [21; 23] and the microflora associated with dry-aged meat (yeasts and molds) may contribute to flavor compounds and increase the rate of proteolysis [24; 25]. Dry-ageing has been proposed as an intervention that may add value to mutton by increasing consumer liking for mutton. Recent investigations into the consumer response to wet- and dry-aged mutton have found that dry-ageing can indeed increase mutton liking for some consumers, but it can also reduce mutton liking for other consumers [26]. [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [26] also found that flavor is the most important driver of consumer liking for mutton followed by tenderness and juiciness; however, the consumer perceived flavor profile of wet- and dry-aged mutton has not been described. The development of a consumer-centric lexicon describing mutton flavor would support future investigation into the flavor component driving liking (or disliking) for mutton. Recently, check-all-that-apply (CATA) methodologies have successfully been used with consumers to characterize red meat product flavor profiles [27; 28]. It is proposed that this methodology may also capture the differences between dry- and wet-aged mutton flavor. Characterization of wet- and dry-aged mutton flavor profiles will enable articulation of the flavor benefits of dry-ageing mutton for branding and marketing purposes, and the future linking of flavor components to consumer liking or disliking of mutton products. The aim of this study was to assess if consumers could characterize wet- and dry-aged mutton flavor profiles using CATA.