High pressure thermal processing of pears: Effect on endogenous enzyme activity and related quality attributes

Pectin methylesterase (PME) in papaya nectar results in undesirable gel formation and peroxidase (POD) in strawberry nectar leads to nutrient loss, browning, and off-flavor production. Because of this, the effect of alternative processing techniques including ultra high temperature (UHT, 20-135°C, 1-3 s), high pressure processing (HPP, 20 or 60°C, 200-600 MPa) and irradiation (0-10 kGy) on PME and POD activity in papaya and strawberry nectar and their respective blends were compared to traditional thermal processing (80-130°C, 0-10 min). Traditional thermal (110°C, 5 min, 71.5% reduction) and UHT (110°C, 1-3 s, 98.0% reduction) processing were able to sufficiently reduce PME activity and prevent gel formation in papaya nectar. PME reduction was enhanced by synergistic reductions in nectar blends after UHT at 80°C. HPP was unable to prevent gel formation in papaya nectar, with enhanced activity at 400 MPa. Exposure of a blend 50P:50S to 10 kGy irradiation prevented gel formation. UHT enhanced POD activity at 110°C and synergistic reductions resulted for POD activity in nectar blends after irradiation. These findings highlight the benefits of alternative processing in reducing enzyme activity in fruit nectars and nectar blends.

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Effects of High-Pressure Pretreatment and Calcium Soaking on the Texture Degradation Kinetics of Carrots during Thermal Processing

Journal of Food Science ◽

10.1111/j.1365-2621.2004.tb10711.x ◽

2006 ◽

Vol 69 (5) ◽

pp. E205-E211 ◽

Cited By ~ 72

Author(s):

D.N. Sila ◽

C. Smout ◽

T.S. Vu ◽

M.E. Hendrickx

Keyword(s):

High Pressure ◽

Thermal Processing ◽

Degradation Kinetics ◽

Kinetics Of

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In Vitro Protein Disappearance of Raw Chicken as Dog Foods Decreased by Thermal Processing, but Was Unaffected by Non-Thermal Processing

Animals ◽

10.3390/ani11051256 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1256

Author(s):

Hansol Kim ◽

Ah Hyun Jung ◽

Sung Hee Park ◽

Yohan Yoon ◽

Beob Gyun Kim

Keyword(s):

High Pressure ◽

Electron Beam ◽

Thermal Processing ◽

Gamma Ray ◽

Light Emitting Diode ◽

High Pressure Processing ◽

Chicken Meat ◽

In Vitro Assays ◽

Uv Led

The objectives of the present study were to determine the influence of thermal and non-thermal processing procedures on in vitro ileal disappearance (IVID) of dry matter (DM) and crude protein (CP) in chicken meat as dog foods using 2-step in vitro assays. In thermal processing experiments, IVID of DM and CP in chicken meat thermally processed at 70, 90, and 121 °C, respectively, with increasing processing time was determined. For non-thermal processing experiments, IVID of DM and CP in chicken meat processed by high-pressure, ultraviolet-light emitting diode (UV-LED), electron-beam, and gamma-ray was determined. Thermal processing of chicken meat at 70, 90, and 121 °C resulted in decreased IVID of CP (p < 0.05) as heating time increased. In non-thermal processing experiment, IVID of CP in chicken meat was not affected by high-pressure processing or UV-LED radiation. In vitro ileal disappearance of CP in electron-beam- or gamma-ray-irradiated chicken meat was not affected by the irradiation intensity. Taken together, ileal protein digestibility of chicken meat for dogs is decreased by thermal processing, but is minimally affected by non-thermal processing methods.

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