High temperature continuous deep fat frying of foods will result in the frying oil and food quality deterioration. Although the quality can be retained by using fresh oil, this approach will increase the production cost. In this study, quality improvement of used niger seed oil using adsorbent treatment was evaluated. Each adsorbent was mixed with 20 h used niger seed oil (15% w/v) at 150 °C and stirred for 30 min. The oil was recovered through centrifugation at 4200 rpm for 15 min. The tested chemical parameters of the oil increased after 20 h of frying (acid value (AV) (2.24–8.31) mg KOH/gm oil, free fatty acid (FFA) (1.13–4.17) %, and peroxide value (PV) (1.00–13.97 mEq oxygen/Kg of oil). The improvement in free fatty acid, peroxide value and oil recovery upon treatment of the fried oil with ash, bentonite, bleaching earth, silca gel and magnesium oxide (MgO) was (61, 57, 80), (66, 43, 88), (56, 21, 85), (61, 50, 70), and (73, 64, 40) % respectively. Ash and MgO effectively improved the physico-chemical characteristics of the used oil. Thus, the two were selected for further optimization of effective concentration and to evaluate their synergetic effect. Treatments with 2.5, 5.0, 7.5, 10.0, 12.5 and 15.0 % of ash reduced the AV of the fried oil by 26, 39, 46, 53, 53 and 60 % respectively (p < 0.05). Also the combination of ash and MgO (1:1) improved the physico-chemical properties of the frying oil to nearly fresh quality.

对食物进行高温连续深层油炸会导致油炸油和食物质量下降。尽管可以通过使用新鲜油来保持质量，但是这种方法将增加生产成本。在这项研究中，评估了使用吸附剂处理过的尼日尔种子油的质量改进。将每种吸附剂在150°C下与20小时使用的尼日尔种子油（15％w / v）混合，并搅拌30分钟。通过在4200rpm下离心15分钟来回收油。煎炸20小时后，油的测试化学参数增加（酸值（AV）（2.24-8.31）mg KOH / gm油，游离脂肪酸（FFA）（1.13-4.17）％和过氧化物值（PV）（ 1.00–13.97 mEq氧气/千克油）。用灰分，膨润土，漂白土处理煎炸油后，游离脂肪酸，过氧化物值和油回收率得到改善，硅胶和氧化镁（MgO）为（61、57、80），（66、43、88），（56、21、85），（61、50、70）和（73、64、40）％分别。灰分和氧化镁可有效改善废油的理化特性。因此，选择两者以进一步优化有效浓度并评估它们的协同作用。用2.5％，5.0％，7.5％，10.0％，12.5％和15.0％的灰分进行处理，可使油炸油的AV值分别降低26％，39％，46％，53％，53％和60％（p <0.05）。灰分和MgO（1：1）的组合也将煎炸油的物理化学性质提高到几乎新鲜的品质。选择两者以进一步优化有效浓度并评估其协同作用。用2.5％，5.0％，7.5％，10.0％，12.5％和15.0％的灰分进行处理，可使油炸油的AV值分别降低26％，39％，46％，53％，53％和60％（p <0.05）。灰分和MgO（1：1）的组合也将煎炸油的物理化学性质提高到几乎新鲜的品质。选择两者以进一步优化有效浓度并评估其协同作用。用2.5％，5.0％，7.5％，10.0％，12.5％和15.0％的灰分进行处理，可使油炸油的AV值分别降低26％，39％，46％，53％，53％和60％（p <0.05）。灰分和MgO（1：1）的组合也将煎炸油的物理化学性质提高到几乎新鲜的品质。