75 Novel Approaches to Characterize Beef Color Changes

Abstract

Abstract Visual perceptions play an important role in beef purchasing decisions. Any color deviation making beef unacceptable leads to monetary loss and wastage of animal protein. Myoglobin is the primary sarcoplasmic protein responsible for beef color. Myoglobin in beef can exist in three different forms, namely deoxymyoglobin, oxymyoglobin, and metmyoglobin. Depending on oxygen penetration, a thin bright-red layer revealing freshness extends from the surface to the interior. The discoloration is dependent on oxygen partial pressure, and it starts from the interior and extends to the surface. Meat may have a bright red color on the surface, but the metmyoglobin layer starts migrating from the interior, where oxygen partial pressure is between 1-3% interference. During early post-harvest (up to 14days), beef can limit discoloration by the mechanism of inherent metmyoglobin reducing capacity (metmyoglobin formed will be reduced back to deoxymyoglobin and allow oxygen to bind to form bright-red color). The currently used spectrophotometric methods quantify the surface color due to shallow penetration of the myoglobin-probed light associated with the surface-applicator configuration. This presentation will discuss two novel approaches to quantity meat color. First, a novel in-house near-infrared-based needle-probe spectrophotometer was designed to assess interior meat color changes. This approach will help differentiate surface and interior meat color changes. In the second approach, electrochemical sensing will help understand the metmyoglobin reducing capacity of meat. These novel techniques demonstrate the potential to characterize color changes for minimizing losses due to discoloration.