# Proteomic, Fatty Acid and Mineral Profiles of PDO Arouquesa and Commercial Crossbred Beefs: A Tool for Certification

## TL;DR

This study compares the nutritional and proteomic profiles of Arouquesa and crossbred beef to identify unique markers that could help authenticate PDO-certified meat.

## Contribution

The study identifies specific proteins and molecular markers that distinguish Arouquesa beef, supporting the authentication of PDO-certified products.

## Key findings

- Arouquesa beef has higher energy content and healthier fatty acid profiles compared to crossbred beef.
- Proteomic analysis revealed 34 differentially abundant proteoforms linked to meat quality traits like tenderness and color.
- Key proteins related to muscle contraction, glycolysis, and oxygen transport are more abundant in Arouquesa beef.

## Abstract

Beef certified under the Protected Designation of Origin (PDO) label, such as Arouquesa beef, is valued for its unique taste and quality. This is due to the traditional farming methods that are based on slow growth rates and the use of local breeds. However, these native breeds produce less meat than commercial crossbred animals. This study compared meat from Arouquesa cattle with meat from crossbred animals to understand the differences and to add value to PDO products. We measured basic nutritional values, including protein and energy content, and analyzed the fatty acid profile and the proteome. Arouquesa beef contained more energy and a healthier fatty acid profile. The proteome analysis revealed specific molecules that influence flavor, tenderness, and color in Arouquesa beef. These findings describe the molecular background of the distinctive qualities of traditional-produced meat. The identified proteins can also serve as possible biomarkers to authenticate PDO products, ensuring the specifications of high-quality beef linked to its traditional system. This study contributes by adding value to local breeds and traditional livestock systems that assists with sustainable agriculture and rural development.

Protected Designation of Origin (PDO) beef products are recognized for their higher quality, although the native breeds used often show lower productivity compared to commercial crosses. This study aimed to compare the proteome profiles of Arouquesa and crossbred beef using 2D-DIGE, and evaluating crude protein, energy, and fatty acid composition. Arouquesa beef had higher energy values (p < 0.05), whereas crossbred samples showed greater protein content (p < 0.05). Moreover, Arouquesa beef had higher proportions of microminerals, namely zinc, iron, and manganese (p < 0.05). The Arouquesa breed also presented higher proportions of most fatty acids, including saturated, monounsaturated, and polyunsaturated. Proteomic analysis identified 34 differentially abundant proteoforms from 23 proteins. In Arouquesa, proteins associated with muscle contraction (MYLPF, TNNT1), glycolysis/gluconeogenesis (TPI1, GPD1), oxygen transport (HBB, HBA), and heat shock response (CRYAB, HSPB1) were more abundant or had altered spot patterns, suggesting their roles in meat tenderness, color, and fat-related characteristics. Conversely, crossbred beef showed elevated levels of glycolytic enzymes (PGM1, ENO3, and some proteoforms of TPI1 and GPI) and structural proteins (MYL1), related with higher muscle growth and different fiber composition. The identified proteins provide possible molecular markers that distinguish Arouquesa from commercial breeds. These validated proteins in the future can support breed characterization and verification of PDO certification specifications.