Machine Vision Requires Fewer Repeat Measurements than Colorimeters for Precise Seafood Colour Measurement.

The colour of seafood flesh is often not homogenous, hence measurement of colour requires repeat measurements to obtain a representative average. The aim of this study was to determine the optimal number of repeat colour measurements required for three different devices [machine vision (digital image using camera, and computer processing); Nix Pro; Minolta CR400 colorimeter] when measuring three species of seafood (Atlantic salmon, Salmo salar, n = 8; rockling, Genypterus tigerinus, n = 8; banana prawns, Penaeus merguiensis, n = 105) for raw and cooked samples. Two methods of analysis for number of repeat measurements required were compared. Method 1 was based on minimising the standard error of the mean and Method 2 was based on minimising the difference in colour over repeat measurements. Across species, using Method 1, machine vision required an average of four repeat measurements, whereas Nix Pro and Minolta required 13 and 12, respectively. For Method 2, machine vision required an average of one repeat measurement compared to nine for Nix Pro and Minolta. Machine vision required fewer repeat measurements due to its lower residual variance: 0.51 compared to 3.2 and 2.5 for Nix Pro and Minolta, respectively. In conclusion, machine vision requires fewer repeat measurements than colorimeters to precisely measure the colour of salmon, prawns, and rockling.

Muscle fibre type composition influences the formation of odour-active volatiles in beef.

Flavour is a key driver of consumer liking, and odour-active volatiles formed in cooking are important contributors to the flavour of cooked beef. We hypothesised that the formation of odour-active volatiles in beef are influenced by the contents of type I oxidative and type II glycolytic muscle fibres. To test our hypothesis, we combined ground masseter (type I) and cutaneous trunci (type II) into beef patties, cooked them, then their volatile profiles were analysed using gas chromatography-mass spectrometry. Antioxidant capacity, pH, total heme protein, free iron, and fatty acid composition of these patties were also measured to investigate their relationship to volatile formation. Our study showed that beef composed of more type I fibres had higher 3-methylbutanal and 3-hydroxy-2-butanone, but less lipid-derived volatiles, and this could be partially attributed to the higher antioxidant capacity, pH, and total heme protein content in type I fibres. The results of our study indicate that fibre-type composition plays an important role in volatile formation and hence flavour of beef.

Bushfire exposure is associated with increased pH and dark-cutting in beef longissimus thoracis at grading.

To investigate if bushfire exposure is associated with increased loin pH, this study analysed temporal and geospatial data on fire incidence in South-Eastern Australia together with beef carcase quality and production records for fire affected animals (n = 451,299). Two outcomes were modelled: 1) loin pH at time of grading, and 2) the incidence of "high pH" defects (pH > 5.70). For both models, decreasing "time since closest fire" and "distance of property from closest fire" were associated with increasing loin pH and increased incidence of high pH carcases(p < 0.05 for all); interactions for "distance from the closest fire" with feed type (grain vs grass) and "days of fire exposure" with HGP (hormonal growth promotant) treatment (yes vs no) (p < 0.05 for both) indicate high pH outcomes were exacerbated in grass-fed and HGP treated cattle. It is concluded that exposure to bushfire is associated with increasing pH but the extent and magnitude of these increases are modulated by production factors.

Combining hierarchical clustering and preference mapping differentiates consumer preference for dry aged mutton.

Dry ageing of mutton may enhance mutton's consumer appeal; however, consumer acceptance of mutton is heterogeneous. To identify which consumers prefer dry aged mutton, dry (DA) and wet aged mutton (WA) loin and topside were rated by consumers (n = 540) for tenderness, juiciness, liking of flavour and overall liking on a 0-100 scale. Two predictive liking models were developed, utilising either consumer clusters (identified by agglomerative hierarchical clustering) which related to mutton liking and ageing method preference, or demographic factors. The cluster based model had the highest explanatory power. Cluster 1 (n = 219) preferred DA (p < 0.001), rating it 5.9 points higher than WA, cluster 2 (n = 235) had no ageing method preference (p > 0.05), and cluster 3 (n = 79) preferred WA (p < 0.001), rating WA liking 8.3 points higher than DA. Cluster characterisation identified some differences between clusters that may relate to consumer ethnicity and familiarity with mutton.

High consumer acceptance of mutton and the influence of ageing method on eating quality.

To compare the eating quality (EQ) of wet (WA) and dry aged (DA) mutton longissimus thoracis et lumborum (LTL) and semimembranosus (SM), bone-in leg and loin primals from 81 merino cull ewes were WA or DA for 14, 28, 42 or 56 days. Untrained consumers (n = 540) assessed the excised LTL and SM for EQ (tenderness, juiciness, liking of flavour and overall liking, 0-100), quality grade and respective willingness to pay (WTP). LTL scored higher than SM for EQ, P < 0.001 for all consumer sores. Mean LTL EQ scores were > 70 and mean SM EQ scores >54. Ageing method had no significant effect on LTL or SM EQ (P > 0.05 for all consumer scores). Ageing beyond 14 days improved SM and LTL tenderness. Consumers most often graded LTL and SM quality grades as "better than everyday" and "good everyday" respectively; corresponding WTP was 26.90 $AUD/kg and 18.80 $AUD/kg. Extended ageing periods improved mutton tenderness.

Consumer Characterization of Wet- and Dry-Aged Mutton Flavor Profile Using Check-All-That-Apply.

The aim of this study was to assess if consumers could characterize wet- and dry-aged mutton flavor profiles using CATA (check-all-that-apply). A flavor lexicon was developed for mutton, and consumers assessed wet- and dry-aged mutton patties against this lexicon using CATA methodology. Results indicate that consumers most often associated caramel and roasted flavors with dry-aged patties, and "sheepy" and metallic flavors with wet-aged patties. Volatile analysis supported the consumer characterization as there were more Maillard reaction products, including pyrazines, which are associated with roasted and cooked flavors, found in the dry-aged patty volatile profile. More 1-octen-3-one, which is associated with metallic flavors, was found in the wet-aged patty volatile profile. These results provide validation that the lexicon utilized in this study (i) is suitable for the characterization of mutton flavor and (ii) will have applications for future investigations into the flavor components driving consumer liking for mutton.

Product Design to Enhance Consumer Liking of Cull Ewe Meat.

The global sheepmeat industry aspires to increase consumer liking for cull ewe meat and thereby increase its value; dry ageing application can increase the consumer appeal of this meat. In order to develop novel consumer-liked dry aged sheepmeat products, an innovation process aligned with design thinking principles was initiated. The objective was to understand optimal dry aged sheepmeat product formats from chef, butcher, producer and consumer perspectives, and use these findings to develop "highly liked" and "premium" dry aged cull ewe meat dishes. The methodology used and the results of stakeholder engagement, perceptual mapping, and quantitative consumer assessments are reported. Stakeholder engagement showed the importance of how novel products are introduced to the consumer and to the chef. Perceptual mapping highlighted that chef-perceived product "premiumness" was driven by eating quality and complexity of the dish. Consumer assessment validated these findings with increases in dish liking associated with increased premiumness and complexity in dish presentation. Overall, the described approach was successful; eight highly liked dry aged cull ewe meat dishes were developed (all scored > 7.69 on a 9-point hedonic scale for liking), and four of the eight dishes were rated "at the level of a very premium food".

A Mixed Method Approach for the Investigation of Consumer Responses to Sheepmeat and Beef.

Coupling qualitative and quantitative consumer research methodologies enables the development of more holistic and comprehensive perspectives of consumer responses. In this study, consumer responses to beef and sheepmeat were investigated using a mixed method approach combining perceptual mapping (qualitative), and sensory (quantitative) methodologies. Qualitative insights indicated Australian and Asian consumers differ in perception of familiarity and 'premiumness' of meat products. Specific findings included: Australians consume grilled or roasted meat as a centre of the plate 'hero' ingredient, while Asians prefer stovetop cooking methods where meat is one ingredient in a complex dish. Labelling meat as 'Australian' was important for Australian consumers but not for Asian consumers. Quantitative data demonstrated that older consumers (31-70 years) scored sheepmeat higher than younger consumers (18-30 years) for healthiness (p = 0.004), juiciness (p = 0.029), odour liking (p = 0.005) and tenderness (p = 0.042). Older consumers also had a lower willingness to pay than younger consumers for "premium" quality meat; 30-40 vs. 40-50 AUD (Australian dollar) per kg respectively for sheepmeat, and 40-50 vs. 50-60 AUD per kg respectively for beef. In conclusion, the approach used effectively integrated consumer attitudes, usage information and sensory assessments with socio-demographic factors to generate insights for the refinement of market strategies and product offerings.