Freeze-dried persimmon peel: A potential ingredient for functional ice cream

Area of Science:

• Food Science and Technology
• Nutritional Biochemistry
• Materials Science

Background:

• Persimmon peels are often discarded waste products, yet they contain valuable phenolic compounds, dietary fibers, minerals, and pectins.
• Valorizing persimmon peels can reduce waste and create functional food ingredients.

Purpose of the Study:

• To evaluate the impact of different drying methods (freeze-drying, vacuum oven, oven, microwave) on persimmon peel properties, including antioxidant activity, total phenolic content (TPC), and color.
• To investigate the feasibility of incorporating dried persimmon peel powder (DPPP) into ice cream formulations and assess its effect on product quality.

Main Methods:

• Persimmon peels were subjected to freeze-drying (-85°C for 24h), vacuum oven drying (45°C for 12h), oven drying (50°C for 12h), and microwave oven drying (900W for 10s).
• Antioxidant activity (IC50), total phenolic content (TPC), and color parameters (L*, a*, b*) of dried persimmon peels were analyzed.
• Dried persimmon peel powder (DPPP) was added to ice cream at varying levels (0-3% wt.), and properties like overrun, color, hardness, and melting resistance were evaluated.

Main Results:

• Freeze-dried persimmon peels exhibited the highest values for L*, a*, and b* color parameters and the greatest TPC (673 ± 2.0 mgGAE/100g).
• The lowest TPC was found in oven-dried samples (352 ± 0.5 mgGAE/100g), while oven-dried samples showed the highest IC50, indicating lower antioxidant activity.
• Incorporating DPPP into ice cream significantly increased a*, b*, hardness, and melting resistance, while decreasing overrun and L* values as DPPP content rose from 0 to 3%.

Conclusions:

• Freeze-drying is the most effective method for preserving the antioxidant and phenolic content of persimmon peels.
• Dried persimmon peel powder can be successfully incorporated into ice cream to enhance its functional properties and sensory attributes.
• DPPP presents a promising avenue for creating value-added, functional ice cream products.