Abstract: Abstract：Aqueous extraction processing (AEP) is an environmentally friendly method to extract oil from various plants at amoderate temperature. However, the AEP alsohave several limitations. Firstly, the cream can be inevitably produced to form asort of highly stable oil-in-water emulsiondue to the adoption of water, stirring and centrifugation during processing. Theformed emulsion become difficult to break completely, resulting in a huge challenge for the AEP performance. Secondly, thewater that used in AEP normally serves as an extraction medium, but the usage of excessive water can result in the formationof thick suspension, which making it hard to directly release free oil. In general, the ratio of seed to water 1:5 kg/L or evenhigher was mostly chosen as the optimal ratio to eliminate the thick suspension as well as stable cream. However, thesubstantial consumption of water increased the treatment cost of subsequent wastewater after processing. A modified aqueousextraction of flaxseed oil was investigated using a low consumptionof water under acidic wetting and drying, in order toenhance the AEP extracted yield of free flaxseed oil,while decrease the consumption of enzyme and water. The results showedthat the yield of free oil was improved significantly due to the solubility effects of flaxseed protein under the pretreatment ofacidic moisture-conditioning plus drying. In untreated flaxseed kernels, the free oil yield was only 18.95% ± 0.91%, while71.29% ± 1.87% of the extracted oil went preferentially into the cream fraction. By contrast, the free oil yield increased to83.27%±0.67% with the pretreatment of acidic moisture-conditioning plus drying. There was a vast increase in the amount ofprotein distribution in sediment phase under the pretreatment (from 33.34% ± 0.34% to 60.25% ± 0.44%), while the proteindistribution in aqueous phase consequently decreased from 66.74±1.04% to 39.78%±0.66%. Processing conditions of aqueousextraction were also optimized by single-factor experiments, and the optimal parameters were obtained as follows: theextraction temperature was 50 ℃ , pH value was 9.0, the ratio of flaxseed to water was 1: 2.5 kg / L, extraction time wastwohours. The recovery of free oil was achieved 82.88%±0.30% under the optimum conditions. Due to the increase of proteincontent in sediment phase and low flaxseed to water ratio of 1:2.5 kg/L, a part of oil was entrapped in sediment phase, whichlimited the further improvement of total oil yield. The sediment phase was further extracted by the aqueous phase plusdeionized water,wherethe quality of deionized water was 50% quality of raw materials. The oil that distributed in sedimentphase decreased from 3.97%±0.11% to 2.09%±0.04%after the second extraction. Subsequently, different enzyme and freezethaw were used to treat the demulsification of residual emulsion.The total yield of free flaxseed oil was 93.44%±0.29% afterthe residual emulsion was demulsified with papain. After detecting the characteristic value of flaxseed oil from aqueousextraction processing and pressing extraction, the experiment came to a conclusion:There were no significant differences thatobserved on therefractive index, iodine value, conjugated diene value and conjugated triene value. Although the peroxidevalue of flaxseed oil by aqueous extraction processing was slightly higher than that by pressing extraction,it still well belowthe maximum value of cooking oil (10 mmol/kg).These findings demonstrate that the proposed pretreatment with low waterconsumption under acidic moisture-conditioning plus dryingis suitable for the aqueous extraction of flaxseed oil. Therefore,this presented study can provide a promising technology for the extraction of flaxseed oil, where can increase the free oilrecovery, while reduce the water consumption and the amount of enzyme.