ORIGINAL PAPER M. Isabel Cambero ? Carlos J. Jaramillo Juan A. Ordon Äez ? Angel Cobos Claudia I. Pereira-Lima Gonzalo D. Garcõ Âa de Fernando Effect of cooking conditions on the flavour compounds and composition of shrimp (Parapenaeus longirostris) broth Received: 22 September 1997 / Revised version: 13 November 1997 AbstractmTo achieve a shrimp broth with the best flavour, the whole shrimp must be cooked at 85°C for 30 min in a 0.5% NaCl solution in proportions 1 : 2 (w : v). Quantita- tively, the main components of the broth were nitrogen substances, the most abundant of these being peptides of molecular weight less than 600 Da. Levels of ATP meta- bolites were also determined [the more abundant com- pounds were inosine, guanosine 59-monophosphate (GMP) and inosine 59-monophosphate (IMP)], as were free sugars (glucose, fructose and ribose) and fat content. The free amino acid composition was also determined. A significant correlation (P 50.0001) between cooking tem- perature and different nitrogen fractions was observed. Key wordsmShrimp broth ? Flavour ? Cooking conditions Introduction Since ancient times, people have eaten seafood products because of their undoubtable nutritive value and their delicious and very diverse flavours. The shrimp processing industry has a turnover of several hundred million dollars a year. Between 1982 and 1990, the per capita consumption of shrimps in the European Union increased from 0.51 to 0.82 kg/year and in Spain from 0.67 to 1.87 kg/year [1]. Determination of the active components of shrimp broth flavour will be of great help in the development and production of diverse shrimp flavours. In the near future more and better flavours will be required to meet the predicted increase in demand, not only for formulated foods, such as surimi-based products, but also for natural ones; for example, cultured fish and shellfish have been shown to have less flavour than wild ones [2]. Research in this line has focused on extracting the active flavour compounds in shrimp waste. These substances could be used as feeding stimulants for fish or as seafood flavourings and could be incorporated into soups and/or surimi-based products [3 ± 5]. Free amino acids (glycine, alanine, proline, glutamic acid, methionine and histidine), dipeptides (anserine and balenine), nucleotides and related compounds [inosine 59- monophosphate (IMP), guanosine 59-monophosphate (GMP) and hypoxanthine], quaternary ammonium bases (glycine betaine and trimethylamine oxide) and organic acids (succinic acid) have so far been reported to be responsible for seafood flavours. Konosu et al.[6] reported that eight nitrogen compounds [glycine, alanine, glutamic acid, arginine, adenosine 59-monophosphate (AMP), GMP, cytidine 59-monophosphate (CMP) and glycine betaine] and four inorganic ions (Na + ,K + , Cl ± and PO4 3± ) are essential for the characteristic taste of crab meat. This study suggests that the flavour of a particular type of seafood may be caused by specific components rather than by different concentrations of the same substances. Different studies of the flavour of cooked crustaceans have used a wide variety of heat treatments. For example, Konosu et al. [6] and Hayashi et al. [7] studied the flavour components of several boiled crabs and snow crabs, re- spectively, by boiling them in a saline solution (3% NaCl) for 15 ± 25 min, while Shenderyuk et al. [8] boiled shrimps in an 8% NaCl solution for 15 min in order to investigate its volatile nitrogenous bases and their role in the aroma of boiled shrimps. As far as we know, only the Hayashi M.I. Cambero ( ) ? J.A. Ordon Äez ? G.D. Garcõ Âa de Fernando Departamento de Nutricio Ân y Bromatologõ Âa III (Higiene y Tecnologõ Âa de los Alimentos), Facultad de Veterinaria, Universidad Complutense, E-28040 Madrid, Spain e-mail: icambero@eucmax.sim.ucm.es C.J. Jaramillo Departamento de Medicina Preventiva y Salud Pu Âblica, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Auto Ânoma de Me Âxico, Mexico A. Cobos Departamento de Quõ Âmica Analõ Âtica, Nutricio Ân y Bromatologõ Âa, Facultad de Ciencias de Lugo, Universidad de Santiago de Compostela, Spain C.I. Pereira-Lima Servic Ëo de Inspec Ëao de Produto Animal, Ministe Ârio da Agricultura, Belo Horizonte, MG, Brazil Z Lebensm Unters Forsch A (1998) 206: 311 ± 322 Ó Springer-Verlag 1998