Impact of Heat Treatment on Hard Cider Enriched with Cryo-Concentrated Apple Must: Microbiological Profile, Functional Properties, and Storage Stability
Matheus de Melo Carraro, Isabela Maria Macedo Simon Sola, Raul Dias Moreira dos Santos, Ivo Mottin Demiate, Aline Alberti, Alessandro NogueiraThis study evaluated the impact of heat treatment on the microbiological, chemical, and functional properties of hard cider enriched with cryo-concentrate over 180 days of storage. The experimental protocol for the hard cider was assessed under three conditions: room temperature (18–23 °C, CA), refrigeration (7–8 °C, CR), and pasteurization at 60 °C for 15 min (P60) and 80 °C for 15 min (P80). The heat treatment employed was mild to preserve the hard cider’s quality. Microbiological results confirmed proper processing conditions. Pasteurization reduced the initial populations of molds and yeasts by 92.9% (P80) and 83.3% (P60), while lactic acid bacteria decreased by over 99.0%. Microbial counts in P60 and P80 continued to decline during storage. Sugar content was the main indicator of instability in P60, particularly at 60 days. Both P60 and P80 ciders exhibited similar reductions in antioxidant activity, with DPPH showing a reduction of 43–45% and ABTS exhibiting a decrease of 50–51%. Additionally, a twofold increase in color intensity (darkening) was observed during storage in heat-treated samples. These findings demonstrate that pasteurization at 80 °C for 15 min effectively extends the shelf life of hard cider with cryo-concentrate to six months at room temperature, offering a practical solution for commercial production.