Apple pomace is a good matrix for phytochemical retention

Area of Science:

• Food Science
• Food Chemistry
• Nutritional Science

Background:

• Apple pomace and pulp are rich sources of bioactive compounds.
• Storage conditions significantly impact the stability of phytochemicals and color in dried fruit products.
• Understanding water activity's role is crucial for preserving food quality.

Purpose of the Study:

• To investigate the effect of water activity on phytochemical content and color changes in dried apple pomace and pulp.
• To determine the degradation kinetics of antioxidants and color during storage.
• To compare the stability of phytochemicals and color between apple pomace and pulp.

Main Methods:

• Dried apple pomace and pulp mixtures were stored at various water activities (0.11-0.75) and 30 °C for 9 months.
• Water mobility was assessed using proton nuclear magnetic resonance ((1)H NMR).
• Antioxidant degradation kinetics (first-order) and color changes (zero-order) were analyzed.

Main Results:

• Increasing water activity accelerated phytochemical degradation and color changes.
• Apple pomace exhibited significantly greater stability, with 2-6 times lower degradation rates for phytochemicals and color compared to pulp.
• Lower water mobility in pomace correlated with its enhanced stability.

Conclusions:

• Apple pomace demonstrates superior phytochemical retention and color stability during storage compared to apple pulp.
• The reduced water mobility in apple pomace is a key factor in its stability.
• Apple pomace is a promising food ingredient for preserving bioactive compounds and developing stable food matrices.