Sensory and Physicochemical Assessment of Wild And Aquacultured Green and Black Lip Abalone (Haliotis laevigataandHaliotis rubra)

Abstract

Abalone is a highly valued food product in many countries, in large part a result of its unique sensory properties. Wild and cultured abalone both attract premium prices, but generally this is not based on sensory characteristics. Yet, abalone aquaculture is developing to provide an alternative to a dwindling supply of wild abalone, and this provides an opportunity to optimize the sensory properties if they are better understood. In most natural food products, farming practices and growing environment are responsible for the sensory properties of the final product; therefore, the comparison of both wild and aquacultured abaloneÕs sensory characteristics could contribute to a better understanding of the impact of the growing and farming practices on the sensory properties. Our study focused on the development of a descriptive sensory analysis methodology to measure abalone sensory properties, and the observation of differences among the abalone sampled. Wild and aquacultured abalone were prepared according to a standardized cooking protocol. A sensory panel of trained assessors developed and defined a descriptive vocabulary and a method of assessment, and then quantified the sensory properties of abalone. A vocabulary of 16 terms describing aroma, texture, flavor, and aftertaste of the abalone was developed. Very significant differences were found between abalone sourced from the wild and aquacultured abalone from different sources. The wild-caught blacklip abalone, which were larger in size, were perceived as more firm, springy, and chewy, but also rated significantly higher in aroma, flavor, and aftertaste impact as well as earthy and metallic flavors. Significant differences in sensory properties were also found between cultured abalone fed different diets. Compositional analysis showed significant differences between abalone in their content of glycogen (range, 4.8%-23.2% of dry weight (DW)), moisture (69.4%-73.7% live weight), and taste-active free amino acids, especially glycine (3.4-18.2 mg/g DW) and glutamate (1.0-3.6 mg/g DW). Correlations were found between sensory attributes and some chemical compounds. This study indicates that growing conditions as well as growing techniques may have a large influence on abalone sensory characteristics. However, because the design of the study was not balanced for key growth or production variables, additional studies are required to identify and quantify which factors were most influential. The descriptive sensory method developed was successful in measuring the sensory properties of abalone and can now be applied more broadly.

Growth performance and feed utilisation of Australian hybrid abalone (Haliotis rubra × Haliotis laevigata) fed increasing dietary protein levels at three water temperatures

“…Clearly, modifications to dietary strategies must take into account more than growth performance in order to properly assess the practical feasibility of the proposed alteration (35) . For example, excess levels of dietary protein may elicit a series of negative consequences, including a deterioration of the nutritional quality of abalone tissue (36,37) , a dietary nutrient imbalance •66…”

“…Clearly, modifications to dietary strategies must take into account more than growth performance in order to properly assess the practical feasibility of the proposed alteration ( 35 ) . For example, excess levels of dietary protein may elicit a series of negative consequences, including a deterioration of the nutritional quality of abalone tissue ( 36 , 37 ) , a dietary nutrient imbalance and resultant displacement of other dietary nutrients leading to the catabolism of comparatively expensive dietary protein to meet energy requirements and also negative environmental consequences such as water quality deterioration ( 17 , 21 , 38 , 39 ) . Further, higher dietary protein inclusion levels may increase the cost of formulated feeds and relatedly the cost of production ( 24 ) , and this is almost certainly the case for aquafeed formulated for most shellfish species where an increase in dietary protein is typically at the expense of a cheaper raw material (e.g.…”

Therapeutic potential of abalone and status of bioactive molecules: A comprehensive review

“…However, significant differences have been found between farmed and wild-caught H.rubra (blacklip) abalone. In a study by Cochet et al (2013) wild-caught blacklip abalone were firm, chewy, higher in aroma, flavour and aftertaste and larger in size when compared to farmed abalone. Furthermore, wildcaught and farmed abalone also varied with respect to chemical composition; it might be due to change in growing conditions as well as growing techniques (Cochet et al, 2013).…”