Impact of ice pack quantity and external temperature on chicken meat freshness during distribution in insulated boxes

The proportion of livestock products purchased via online delivery has increased, emphasizing the need for standards to ensure the freshness and safety of perishable items like chicken. Microbial growth during chicken distribution is strongly influenced by external temperature, highlighting the importance of proper temperature control. This study evaluated the effects of external temperature and the number and spatial arrangement of ice packs on chicken quality in insulated boxes under simplified online delivery conditions. Samples were stored with ice packs at refrigerated (2 °C), ambient (25 °C), and high (40 °C) temperatures. At ambient and high temperatures with two ice packs, the total viable counts (TVC), volatile basic nitrogen (VBN), and thiobarbituric acid reactive substances (TBARS) significantly increased (p < 0.05), exceeding the freshness limits (6.7 log CFU/g for TVC, 20 mg% for VBN, and 0.20 mg MDA/kg for TBARS) by day 2. Spoilage also occurred when using four ice packs at ambient temperature, indicating their limited effectiveness in maintaining microbiological quality. Microbial indicators responded more sensitively to external temperature than chemical indicators and were affected by the spatial positioning of ice packs, indicating that optimized ice pack placement can delay spoilage. These findings emphasize the need for enhanced cold chain management strategies, including refrigerated vehicles and optimized thermal packaging. The absence of clear regulatory standards for temperature control during online meat distribution highlights the urgent need for institutional reforms to ensure the microbial safety and freshness of poultry products.