Accelerated aging by the freezing/thawing process: effects on the technological and sensorial quality of wet- and dry-aged beef

Abstract

This study evaluated the effects of freezing/thawing as a way of accelerating the maturation process, in different systems (wet aging, WA, and dry aging, DA) of beef from Nelore animals and the F1 Nelore x Angus cross (F1Angus). In the first experiment, non-frozen and frozen/thawed strip loins steaks from Nellore animals were matured for 0, 14 and 28 days in both systems (WA and DA) and evaluated for technological and microbiological quality and volatile compounds (VOC) profile. Freezing/thawing provided greater weight losses (P<0.05) in both maturation systems, but the losses were compensated by reducing the maturation time to 14 days in the DA system, unlike the WA system. In addition, frozen/thawed samples showed (P<0.05) higher total bacteria count (5.49 logs CFU/g), but without compromising microbiological quality, and higher tenderness rate (lower values of fragmentation index and strength shear strength and greater sensory tenderness). On the other hand, freezing/thawing provided (P<0.05) lower color intensity (lower C*), with greater instability of the myoglobin pigment and, therefore, oxidation to metmyoglobin, with DA samples being darker (lower L*). In the second experiment, strip loins steaks from Nellore and F1Angus animals were dry-aged in the conventional process (not frozen) for 28 days (NF28d) and in the accelerated process (frozen/thawed) for 14 days (FT14d), and evaluated for technological quality, sensory (descriptive profile check-all-that-apply – CATA – and acceptance) and the profiles of volatile compounds (VOC), fatty acids (FA) and amino acids (AA; in the cooking exudate). The accelerated maturation process modified the VOC, AA and AG profiles, improving the flavor and aroma. Nelore FT14d and F1Angus FT14d and NF28d samples were related to VOCs acetoin, 2-methylbutanal and 3-methylbutanal and a greater variety of amino acids in the exudate. In mature samples of Nellore and F1Angus, consumers noticed differences (P<0.05) in 10 sensory characteristics that contributed to discriminate them in the CATA, mainly in relation to appearance and texture attributes. Nellore FT14d meat was similar to F1Angus FT14d and NF28d meat for the overall impression, which were equally accepted by consumers, with scores ranging from “I liked it moderately (7)” to “I liked it a lot (8)”. It was concluded that the accelerated maturation process in the DA system is advantageous, as it allows achieving the desired tenderness and flavor profile in a shorter time, without increasing costs with mass losses or impairing microbiological safety. In addition, the accelerated maturation process allows improving the sensory characteristics of meat from animals with less marbling (Nelores), matching them to meat from F1Angus animals, being a viable and competitive alternative for commercialization.