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Percorrer por autor "Ribeiro, Ana J."

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  • Dry-aged beef: a global review of meat quality traits, microbiome dynamics, safety, and sustainable strategies
    Publication . Ribeiro, Ana J.; Silva, Filipe; Teixeira, Paula; Saraiva, Cristina M.
    Dry-aged beef is valued for its tenderness, complex aroma, and concentrated flavor. However, variability in aging protocols and limited understanding of underlying biological and technological processes can compromise consistent quality and safety. This review examines factors influencing meat characteristics, including genetics, breed, sex, age, diet, intramuscular fat deposition, antioxidant reserves, and endogenous enzyme pools. Postmortem biochemical pathways, such as proteolysis, lipid oxidation, and nucleotide degradation, are discussed in relation to flavor and texture development. The dynamics of surface microbiota are analyzed, highlighting the succession from psychrotrophic spoilage bacteria to molds and yeasts, which collectively form an enzymatic crust that contributes umami and nutty notes while providing antimicrobial barriers. Regulatory frameworks in major markets are reviewed, alongside valorization strategies that convert crust trimmings into umami-rich powders, bioactive peptides, starter cultures, or industrial enzymes. Despite advances, critical knowledge gaps remain, including the functional roles of minor crust taxa, the efficacy of defined starter cultures or bacteriophage blends, and standardized methods for texture and flavor measurement. By focusing on these biochemical and microbiological mechanisms and their applications, this review provides a roadmap for transforming dry aging into a reproducible, safe, and high-quality process in modern meat science.
    2025-10-01Artigo de revisão Acesso aberto Ver mais
  • Mineral profile, oxidative stability and color traits in dry aged meat: integrative analysis
    Publication . Ribeiro, Ana J.; Braga, Fernando G.; Oliveira, Irene; Silva, Filipe; Teixeira, Paula; Saraiva, Cristina M.
    Dry aging enhances beef's sensory quality, but the role of trace-element dynamics in driving physicochemical changes remains unclear. We dry-aged Longissimus lumborum loins (n = 12) for 60 days, sampling on days 1, 14, 35 and 60. Essential (Ca, K, Na, Mg, Fe, Se, Cr, Zn, Cu) and toxic (As, Cd, Co, Pb) elements were quantified by GF-AAS/FAAS; pH and L?, a?, b? color were measured with standard probes; lipid oxidation was assessed via TBARS; and myoglobin redox forms were determined spectrophotometrically. Inner muscle consistently retained higher K, Na, Mg, Zn, Cu and Cr compared to the crust (P < 0.01), reflecting diffusive retention during surface desiccation. Over 60 days, Ca, K, Se and Cr increased (P < 0.01) while Na and Mg decreased (P < 0.001). Iron and zinc exhibited a biphasic pattern, declining to day 35 and rebounding by day 60. Lipid oxidation intensified but remained below sensory rancidity thresholds (TBARS increased from 0.25 ± 0.07 to 0.65 ± 0.33 mg MDA/kg in inner meat and from 0.79 ± 0.15 to 1.53 ± 0.36 mg MDA/kg in crust; P < 0.001), concurrent with a pH rise from 5.61 ± 0.09 to 5.80 ± 0.19 (P < 0.001) and declines of approximately 11 % in redness (a?) and 15 % in yellowness (b?) (P < 0.01). Principal component analysis identified an oxidation-mineral-color gradient (PC1, 30.8 % variance) and a myoglobin-redox axis (PC2, 20.4 %), underscoring mechanistic links between trace element fluctuations, lipid oxidation, and color stability. These results demonstrate that dry aging concentrate minerals and that shifts in Fe, Se, and Zn trajectories modulate oxidative stability, pH drift, and pigment transformations, shaping dry-aged beef color and overall quality.
    2025-09-01Artigo de investigação Acesso aberto Ver mais
  • Time-dependent accumulation of biogenic amines and microbial succession during dry-aging of beef: safety implications
    Publication . Ribeiro, Ana J.; Milheiro, Juliana; Nunes, Fernando M.; Carvalho, Teresa B. de; Barbosa, Joana B.; Silva, Filipe; Teixeira, Paula; Saraiva, Cristina M.
    Dry-aging of beef under controlled temperature, humidity and airflow reshapes the surface microbiota and may influence biogenic amine (BA) accumulation. In this study, culture-based enumeration, 16 S rRNA gene profiling of combined crust + inner meat, and validated HPLC quantification of BAs were integrated to track safety- and quality-relevant changes over 60 days. Sequencing showed Pseudomonadota and Bacillota consistently >95 % of reads; communities were dominated by Pseudomonas, Brochothrix and Psychrobacter, with Acinetobacter rising at mid-aging. Alpha diversity peaked at day 35 (Shannon 1.33???2.12; overall P = 0.0225; day 35 vs day 1, adjusted P = 0.0069) and became heterogeneous by day 60. Culture confirmed a surface-led, aerobic succession: crust counts increased and Pseudomonas reached 5.6 log CFU/g at day 60, whereas inner-muscle counts declined across groups; pathogens were not detected. In the inner meat, cadaverine rose from non-detectable to 31 ± 37 mg/kg at day 60 P < 0.001), spermine peaked at day 35 (52 ± 14 mg/kg; P < 0.001), while histamine remained <5 mg/kg and other BAs showed no significant change. All inner-meat BAs remained below commonly cited concern ranges, though late-stage variance indicates sporadic hot spots, likely reflecting diffusion from the crust and proteolysis-enabled precursor supply. Integrating microbes and metabolites identified two ecological–metabolic tendencies linking psychrotrophic genera with polyamines or diamines. In practice, day 35 emerges as a quality “sweet spot,” whereas approaching day 60 warrants tighter surface management and targeted monitoring of pseudomonads, Enterobacteriaceae and cadaverine/putrescine.
    2026-05-01Artigo de investigação Acesso aberto Ver mais