High Pressure Processed Manuka Honey: Change in Nutritional and Rheological Properties Over 1-Year Storage
First published: 5 September 2016
To elucidate the permanent effect of high pressure processing (HPP) on the quality of Manuka honey, the quality properties such as physicochemical (moisture content, pH, total soluble solids and total solids), nutritional (total phenolic content, antioxidant activity and brown pigment formation), flow behavior and viscosity of HPP-treated Manuka honey were tested. The process condition of HPP (600 MPa/ambient temperature/10 min) was selected and treated samples were stored at 25C in a dark, dry place for 1 year. The moisture content, pH and total solid of HPP-treated honey were changed but statistically insignificant (P > 0.05) after 1 year. An increase in antioxidant activity, total phenolic content and brown pigment during storage were found in HPP-treated samples with maximum value of 90.24 ± 2.4%, 111.19 ± 4.25 mg GAE/kg and 0.26 ± 0.02 AU, respectively. HPP was able to maintain flow behavior with insignificant increase (P > 0.05) in viscosity.
The study on HPP-treated Manuka honey highlights an important proof that this nonthermal technology has a permanent effect on nutritional and rheological properties over 1-year storage. The significant improvement in antioxidant activity, total phenolic content and brown pigment formation of HPP-treated honey is found permanent, following 1-year storage at room temperature. This study has practical implications in establishing efficient process design for commercial manufacturing of high sugar food products and on the potential use of HPP for such products. This will have a strong potential to its continued growth.