Effect of Low Voltage Electrostatic Field Combined with High Humidity Thawing on Water Holding Capacity of Frozen Lamb Meat

Abstract

To investigate the effect of low voltage electrostatic field combined with high humidity thawing on the water-holding capacity of frozen lamb meat, lamb hindleg meat after 24 h of postmortem aging was frozen in a refrigerator at −18 ℃ for 24 h and then thawed. The effects of low voltage electrostatic field combined with high humidity thawing (current of 0.2 mA, voltage of 2 500 V, 4 ℃, and relative humidity of 98%) on the thawing rate, water retention, moisture distribution, carbonyl content, total sulfhydryl content, solubility, surface hydrophobicity, protein secondary structure and protein tertiary structure of lamb meat were evaluated in comparison with those of another three thawing methods: refrigerator thawing (4 ℃, and relative humidity of 55%), low voltage electrostatic field assisted thawing (current of 0.2 mA, voltage of 2 500 V, 4 ℃, relative humidity of 55%), and high humidity thawing (4 ℃, and relative humidity 98%). The results showed that among the four thawing methods, low voltage electrostatic field combined with high humidity thawing had the shortest thawing time (519 min), the lowest thawing loss (3.37%), cooking loss (30.60%), carbonyl content (3.85 nmol/mg) and surface hydrophobicity (21.90 μg), relative content of immobilized water (97.96%) closest to that of fresh meat (98.44%), the highest total sulfhydryl content (28.55 nmol/mg) and solubility (29.98%), and the most stable protein secondary and tertiary structures, indicating that this thawing method shortened the thawing time, effectively inhibited protein oxidative denaturation, and reduced the juice loss, and myofibrillar proteins from the treated lamb meat had the highest water hydration capacity and the best water-holding capacity.

Keywords

• lamb meat; water holding capacity; low voltage electrostatic field; high humidity thawing