Handling of Two Tropical Australian Sharks to Improve Quality and to Identify the Cause of Tough Texture

Sharks caught in tropical Australian waters occasionally exhibit tough texture. Two species of Carcharinid shark, originally known as the sorrah shark (Carcharinus sorrah) and the black spot shark (Carcharinus tilstoni), compose the majority of the catch. Experiments were conducted to identify the cause of tough texture and to improve the overall quality of the catch. The possibility that a cold shock reaction may occur was investigated by observing the contraction of fillets under a range of temperature conditions before freezing. The effect of on-board handling practices were evaluated using frozen shark fillets, which had been stored prior to freezing in refrigerated seawater at different rigor stages, temperatures and times as trunks. Fillets were analyzed for nucleotides, lactate, thaw pH, sarcomere length and raw and cooked shear force values. The existence of thaw rigor was also investigated. There was little difference in the texture between the individual strips of a fillet exposed to different temperatures but there were significant differences between individual sharks. A cold shock reaction could not be demonstrated in these species. The main influences on texture were of biological origin. The species, sex and size were found to have significant links with texture of fillets. The quality of the fillets deteriorated quicker during the warmer season and were at their worst if the trunks were kept on deck till post-rigor or held in 15 degree C refrigerated seawater before freezing

Effect of the puroindoline locus and environment on Chinese fresh noodle texture

Grain produced from doubled-haploid (DH) wheat lines, developed from a hard- and a soft-grained wheat cultivar, were bulked according to Pinb (puroindoline b) genotypes for an assessment of Chinese fresh noodle texture by a trained taste panel. Each DH line was designated as 'soft' or 'hard' grained, based on a PCR amplification of the wildtype, soft allele, or the mutant, hard allele. Theoretically, the soft and hard grain bulks represented respective Pinb alleles and an independent assortment of unlinked alleles from the parents, Sunco and Chuanyu 12. Grains from the parents and DH lines were grown at 2 locations in Queensland, Australia, and one in Sichuan, China. The grains were milled and processed for a taste panel evaluation in Chengdu, Sichuan. Results suggest the Pinb alleles had a significant effect on noodle softness and explained 30% of the variation; the 'soft' Pinb allele conferred a softer noodle texture. Location had a significant effect on noodle smoothness; wheat grain grown at Biloela, Queensland, produced a smoother noodle texture than grain grown in Sichuan. The effect of location confirms the importance of environment as a variable for this quality character. This investigation exemplifies the utility of Pinb markers for specifically altering Chinese Fresh Noodle texture.