High pressure processing (HPP) of honey for the improvement of nutritional value

• High pressure processing shows a great potential in increasing total phenolic content of honey.
• 600 MPa at ambient temperature (≈ 30 °C) for 10 min increased 47.16% of TPC as compared to unprocessed manuka honey.
• To increase TPC in honey, it is preferable to use higher pressure (600 MPa/ambient temperature) than combined HPP- thermal.

The present study was undertaken to assess the effect of high pressure processing (HPP) on total phenolic content (TPC) in manuka honey. Manuka honey is known for its amazing antimicrobial action and antioxidant properties. The effect of HPP (200, 400 and 600 MPa) at ambient and moderate temperatures (53.41 ± 0.30 °C, 65.29 ± 1.77 °C, 71.92 ± 1.63 °C) and their combination for different processing time (5, 10 and 15 min) was investigated. Conventional thermal processing (51.74 ± 0.03 °C, 61.90 ± 0.10 °C and 71.58 ± 0.04 °C) was also carried out as comparison to HPP. Operating HPP at 600 MPa (26.80 ± 0.95 °C–30.18 ± 2.14 °C) for 10 min was found to be the most effective process with 47.16% increment in TPC as compared to unprocessed honey, whereas no significant increase (p < 0.05) was observed in thermal processing as well as in combined HPP–thermal processing. Therefore, HPP at ambient temperatures could be an appropriate method to produce tastier and more nutritive manuka honey.Industrial relevanceThe preservation of total phenolic content (TPC) as a main phytochemical component in honey is very important with direct impact on nutritional value and antioxidant activity. A significant increase in the TPC was obtained by processing. Results demonstrated the HPP capability to increase TPC in manuka honey by 47%. From a nutritional perspective, this result is associated with the production of a higher antioxidant honey, known to prevent certain diseases such as cancer. The study generates a new approach in honey processing which can guarantee the high nutritional quality of honey and its original natural freshness.