Drying-induced physico-chemical changes in cranberry products

Area of Science:

• Food Science
• Nutritional Chemistry
• Agricultural Science

Background:

• Cranberry juice is rich in polyphenols, known for their health benefits.
• Drying processes can affect the stability and retention of these bioactive compounds.
• Understanding the impact of different drying methods and juice formulations is essential for preserving cranberry's nutritional value.

Purpose of the Study:

• To evaluate the effects of freeze-, vacuum-, and spray-drying on polyphenol content in sugar-free cranberry juice and cranberry juice with maltodextrin.
• To compare the retention of total phenolics, flavonols, phenolic acids, procyanidins, and anthocyanins under different drying conditions.
• To investigate the influence of drying on chlorogenic acid content and antioxidant capacity.

Main Methods:

• Sugar-free cranberry juice (XAD) and cranberry juice with 15% maltodextrin were subjected to freeze, vacuum, and spray drying.
• Polyphenol content (total phenolics, flavonols, phenolic acids, procyanidins, anthocyanins) was quantified.
• Chlorogenic acid levels and antioxidant capacity were assessed.
• Impact of temperature during vacuum drying was specifically examined.

Main Results:

• Juice formulation had a greater impact on polyphenol retention than the drying method.
• Spray drying demonstrated competitive polyphenol retention compared to freeze drying.
• Vacuum drying at elevated temperatures (up to 100°C) led to significant polyphenol degradation, except for chlorogenic acid, which increased.
• Increased chlorogenic acid correlated with higher drying impact and accelerated hydroxymethylfurfural formation.
• Antioxidant capacity was primarily influenced by juice formulation and linked to polyphenol content.

Conclusions:

• Juice formulation is a critical factor in preserving cranberry polyphenols during drying.
• Spray drying offers a viable alternative to freeze drying for maintaining polyphenol content.
• Chlorogenic acid behavior under heat suggests a complex interaction during drying, potentially linked to degradation markers.
• The antioxidant capacity of dried cranberry products is directly related to their polyphenol profile and formulation.