Turning Wastes into Resources: Red Grape Pomace-Enriched Biscuits with Potential Health-Promoting Properties

Area of Science:

• Food Science
• Nutritional Biochemistry
• Functional Foods

Background:

• Achieving lifelong adherence to polyphenol-rich diets for cardiometabolic health is challenging.
• Red grape pomace (GP) is a rich source of polyphenols, including anthocyanins, flavonoids, and procyanidins.

Purpose of the Study:

• To evaluate the incorporation of red grape pomace (GP) into biscuits as a strategy to increase dietary polyphenol intake.
• To assess the impact of GP on the nutritional, antioxidant, and sensory properties of biscuits.
• To investigate the effect of GP on in vitro glucose absorption.

Main Methods:

• Crude crushed GP was incorporated at 20% and 30% (w/w) into control (CTR) biscuit formulas.
• Nutritional profiles, polyphenol content (mg GAE/100g), antioxidant capacity, and volatile compounds were analyzed.
• In vitro gastro-duodenal enzymatic digestion was performed to assess glucose absorption.
• Sensory attributes and overall liking were evaluated.

Main Results:

• GP biscuits showed increased fiber and polyphenol content (up to 540 mg GAE/100g) and reduced lipid and energy content.
• GP biscuits exhibited significant antioxidant capacity due to anthocyanins, flavonoids, and procyanidins.
• In vitro digestion revealed that GP significantly delayed glucose absorption compared to CTR biscuits.
• Sensory evaluation indicated that GP incorporation, especially at 20%, did not substantially affect biscuit liking.

Conclusions:

• Red grape pomace biscuits represent a promising functional food, enhancing nutritional value and antioxidant properties.
• The inclusion of GP in biscuits can contribute to a healthier diet by potentially slowing glucose absorption.
• Utilizing grape pomace as a food ingredient offers a sustainable approach to valorize food waste.