Freezing of poultry cuts in continuous convective air blast tunnels is normally performed with the products protected by Low Density Polyethylene (LDPE) as a primary packaging and using Corrugated Cardboard Boxes (CCB) as secondary packaging. The objective of this work was to investigate the influence of these secondary packaging on the freezing of poultry cuts in continuous convective air blast tunnels. The study was performed by replacing CCB with Perforated Metal Boxes (PMB) in order to remove the packaging thermal resistance. The assays, performed in a industrial plant, demonstrated that CCB used commercially for meat freezing have a high heat transfer resistance. Their replacement with PMB can lead to shorter freezing times and spatially homogeneous freezing. Reductions of up to 45% in the freezing times were observed using PMB. The plateau of the temperature curve, related to the freezing time of free water, was significantly reduced using PMB, which is accepted to lead to better product quality after thawing. As the products were protected by the LDPE films as primary packaging, their appearance were not affected. The results presented in this work indicate that replacing CBB with PMB can be an excellent alternative to reduce freezing time and improve freezing homogeneity in industrial air blast tunnels, which could also be applied to other products.28SUPPL.252258(1998) Refrigeration Handbook, Food Storage and Equipment, Food Refrigeration, , ASHRAE - American Society of Heating and Air-Conditioning Engineers, AtlantaBrennan, J.G., (1980) Las Operaciones de la ingenieria de los alimentos, pp. 367-377. , 2 ed. Zaragoza, Espanha: AcribiaLawrie, R.A., (1985) Meat Science, pp. 112-134. , 4 ed. New York: Pergamon PressPardi, M.C., (2001) Ciência, higiene e tecnologia da carne, 1. , 2 ed. Goiânia: UFGResende, J.V., Neves Filho, L.C., Silveira Junior, V., Escoamento de ar através de embalagens de polpa de frutas em caixas comerciais: Efeito sobre os perfis de velocidade em tÚneis de congelamento (2002) Ciência e Tecnologia de Alimentos, 22 (2), pp. 184-191. , maio/agoResende, J.V., Silveira Junior, V., Medidas da condutividade térmica efetiva de modelos de polpas de frutas no estado congelado (2002) Ciência e Tecnologia de Alimentos, 22 (2), pp. 177-183. , maio/agoSantos, C.A., Determination of heat transfer coefficient in cooling-freezing tunnels using experimental time temperature data (2007) Journal of Food Process Engineering, 30 (6), pp. 1-12Silva, J.A., (2000) Tópicos da Tecnologia de Alimentos, pp. 147-159. , São Paulo: Livraria VarelaSingh, R.P., Heldman, D.R., (1977) Introduccion a la ingenieria de los alimentos, , Zaragoza, Espanha: AcribiaVigneault, C., Indirect airflow measurement for horticultural crop package. Part II: Verification of the research tool applicability (2004), pp. 7331-7344. , In: ASAE Annual International MeetingVigneault, C., Castro, L.R., Gautron, G., Effect of open handles on packages during precooling process of horticultural produce (2004), pp. 6901-6908. , In: ASAE Annual International Meeting