The Annals of the University Dunarea de Jos of Galati Fascicle VI – Food Technology, 2003 38 RESEARCHES CONCERNING BIOCHEMICAL STABILITY OF MECHANICAL DEBONED POULTRY MEAT DURING FREEZING Aurelia IONESCU*, Iuliana APRODU*, Margareta Lăcrămioara ZARA*, Gabriela GURĂU** * Galati Dunarea de Jos University, 111, Domneasca St., 800201-Galati, Aurelia.Ionescu@ugal.ro ** Emergency Hospital of Children Sf. Ioan of Galati Abstract The stability under mechanically deboned chicken meat unfreezing conditions was studied. By the storing at –12°C temperature in the presence of the air, the chicken meat is mainly physico- chemically modified; its modifications are especially connected with the lipids oxidative degradation, reactions catalysed by heminic pigments of oxidation shape (Fe 3+ ) formed by the very long action of the packing present air. The TBA index as a measure of the oxidation degree continuously increased during the wholly keeping period. The values more than 4.0 mg malon- aldehide/kg of mechanically deboned chicken meat battery correspond to the development of the rancid smell. Key words: mechanically deboned chicken meat, TBA index, myoglobin, oxidation degradation, lipids, aminic nitrogen, neproteic nitrogen, ammoniacal nitrogen, volatile nitrogen basis Résumé La stabilité dans le régime de la congélation de la viande des vollailles sans os (mécanique) a été investiguée. Par l’emmagasinage à la température –12°C en présence d’air, la viande des vollailles souffre des modifications physiques et chimiques, importantes, liées, partiqulièrement par: la dégradation oxydative des lipids, des réactions catalytiques de pigments héminiques de la forme oxydée (Fe 3+ ), formés par l’action longue d’air présent dans des emballages. L’indice TBA, comme une mesure de la degrée d’oxydation a augmenté continuellement dans la toute période de garde. Les valeurs plus grandes que 4,0 mg malonaldéhyde/kg pâte de la viande des vollailles (méchanique) sont corrélatives bien avec le développement d’odeur rance. Rezumat A fost investigată stabilitatea în regim de congelare a cărnii de pasăre dezosată mecanic. Prin depozitarea la –12°C în prezenţa aerului, carnea de pasăre suferă modificări fizico-chimice importante, legate, în special, de degradarea oxidativă a lipidelor, reacţii catalizate de pigmenţii heminici forma oxidată (Fe 3+ ), formaţi prin acţiunea îndelungată a aerului prezent în ambalaje. Indicele TBA, ca măsură a gradului de oxidare, a crescut continuu pe toată durata de păstrare. Valorile mai mari de 4,0 mg malonaldehidă/kg pastă de carne de pasăre dezosată mecanic se corelează bine cu dezvoltarea mirosului de rânced. 1. Introduction Nutrition has a main role in determining the health estate of a population. This is the reason why nutritive has to be rational and able to activate the metabolism regulating systems. The care for public health is manifested when the quality of food products of any provenience is regarded as a lot of nutritional, sensorial, hygiene and technological characteristics. Nowadays, at world level, has increased the interest for the processed products made on poultry meat. During poultry industrial processing result some anatomic parts (wings, necks, backs), containing meat which is very hard to be