Mejora tecnológica de la fabricación industrial de tentáculos de potón ("Dosidicus gigas") cocinado y congelado

Zusammenfassung

The present doctoral thesis corresponds to an industrial research project whose objective was to improve the technology used to produce a cooked-frozen sliced arms from giant Pacific squid (Dosidicus Gigas). A general restructuring of equipment and processing plant was carried out at the collaborating company. Technological study consisted of eleven tests: Remodelling manufacturing line; Use of marinating by injection to reduce treatment time duration and improve weight yield; Influence of Fishery origin on the composition and yield; Changes in mineral content during maceration and cooking of raw materials from different origin and their possible influence on dietary intakes; Adaptation of marinating media to injection technique; Cooking treatment adjustments to optimize texture; Replacement of cooking broth to avoid colour deviations; Use of culinary preparations based on spices and monosodium glutamate; Freezing by liquid nitrogen to improve texture and colour; Use of glazing agents to improve stability during frozen storage; Use of vacuum packaging to extend the use time duration of thawed product. Depending on the type of test, proximal composition (moisture, total proteins, total lipids and ashes), dehydration (weight losses), colour (CIELab colour), instrumental texture (TPA), sensory (appearance, odour, flavour and texture), nutritional indexes, microbiological counts (Staphylococcus spp., Enterobacteriaceae, E. Coli, mesophilic aerobes, Salmonella spp., and L. monocytogenes), and mineral determinations (using ICP-OES/MS) were performed. Numerous technological improvements were applied. Marinating by injection saved the time necessary for the process, allowing greater production to be achieved. In addition, it reduced water consumption and improves product yield, being sensorially satisfactory and microbiologically safe. Fishery origin of raw material mainly affected yield and composition of final product due to differences in tentacle size and its consequent retention of juices, although barely affected its mineral content. The results indicated that its consumption would not exceed the established dietary intake limits. The use of different maceration media did not produce major differences in terms of performance, but it was possible to decide which of the proposed additives was the most acceptable on a sensory level. The temperature and cooking time did not affect the sensory quality of the product, so it was possible to adjust cooking to minimize juice loss. It was established that it is necessary to replace the cooking broth to ensure that the cooked tentacle has a uniform colour. The use of a spice mixture with a flavour enhancer was positive for the sensory quality of the product. It was not possible to establish whether deep freezing with liquid nitrogen improves texture, elasticity and colour or not, but the reduction in time, workload and energy costs involved in the process must be taken into account. The use of cryoprotectants improved the final presentation of the cooked-frozen squid arms and avoided unwanted effects caused by oxidation. Vacuum packaging of squid arm slice increases the durability of the cooked product once thawed. The experimental activities developed have confirmed that there is a wide margin for improvement in the industrial technology for manufacturing cooked squid arms and probably other similar products.