Understanding consumer liking of beef with particular reference to flavour
Chong, F. S.
University College Cork
This thesis reports the consumer perception for beef eating quality with particular reference to flavour. A study was conducted to investigate if there are regional differences in consumer perception of beef between consumers from different regions. Consumers were recruited from Cork, Belfast and Reading to represent consumers from the Republic of Ireland (ROI), Northern Ireland (NI) and Great Britain (GB). Consumers from Reading scored significantly higher in palatability traits (aroma liking, tenderness, juiciness, flavour liking, overall liking) compared to the other regions although all consumers received portions of same samples. However, consumers from these three regions showed similar preferences towards beef, which indicated that consumer studies conducted in ROI and NI are representative of those in GB. Consumers from Reading were less concerned about the origin of beef and healthiness of beef product. Higher consumption frequency of low-quality cuts was reported by consumers in Reading and thus they gave higher scores for palatability traits when they consumed striploin steak. Four cluster groups were observed using hierarchical cluster analysis and these cluster groups were described as “fastidious”, “tender beef liker”, “bull beef liker” and “easily pleased” consumers. These cluster groups exhibited different scoring patterns and/or preference for beef. Research was commissioned to evaluate the effects of enhancement (kiwi, fig and phosphate solutions) and tenderisation on meat quality with instrumental and chemical analyses. Sugar concentrations were significantly increased and sugar phosphate concentrations were significantly decreased for enhanced beef samples compared to untreated beef samples. A clear muscle effect was observed on volatile composition but the enhancement effects were generally small, probably due to the variation of the extraction method. Automatic solid phase microextraction (SPME) methods were developed to improve the labour intensive manual SPME method. Three general criteria were considered, including flexibility of the method, amount of sample required and ease of use. Specific criteria such as detection range of volatile compounds, quantity of compounds detected, reproducibility and the ability of the method to differentiate beef samples processed under different conditions. Two methods were selected, automatic SPME-cored beef (CAR/PDMS fibre) and automatic SPME- liquid nitrogen homogenised beef (DVB/CAR/PDMS fibre), each had their own advantages and disadvantages. A study conducted in this thesis showed that post-mortem ageing (14, 21 or 49 days), muscles (rump, striploin) and packaging methods (vacuum skin packaging, overwrapped, modified atmosphere packaging) had significant impact on the quantities of volatile compounds. Beef aged for longer period had higher quantities of Strecker aldehydes, n-ketones and pyrazines. Differences in lipid content may explain the differences in the quantity of volatile compounds, which was clearly indicated using principal component analysis. These data indicated that modified atmosphere packaging induced generation of lipid degradation compounds may have reduced the consumer liking for these beef samples.
Beef , Consumer , Sensory , Volatile analysis , Flavour Chemistry , Solid phase microextraction
Chong, F. S. 2020. Understanding consumer liking of beef with particular reference to flavour. PhD Thesis, University College Cork.