复配抗氧化剂在牡丹籽油乳液中的抗氧化作用研究

为提高牡丹籽油乳液的氧化稳定性，将叔丁基对苯二酚（TBHQ）与天然抗氧化剂（生育酚、抗坏血酸）进行复配，测定不同抗氧化剂对牡丹籽油乳液的抗氧化作用，并分析了不同复配抗氧化剂的相互作用机制。结果表明：在贮藏30 d时，添加和未添加抗氧化剂牡丹籽油乳液的粒径相较于0 d 均略有增加，200 mg/kg TBHQ与800 mg/kg抗坏血酸复配时乳液的Zeta电位绝对值最大，且抗氧化作用最强；TBHQ与抗坏血酸表现出较好的协同抗氧化作用，与生育酚表现出拮抗作用；TBHQ与生育酚之间拮抗作用的原因主要是TBHQ减少了生育酚在牡丹籽油乳液中油水界面的含量，而TBHQ与抗坏血酸之间协同作用主要是由于抗坏血酸增加了TBHQ在牡丹籽油乳液中油水界面的含量。综上，TBHQ与抗坏血酸复配能提高牡丹籽油乳液的氧化稳定性。     

Antioxidants in lipid foods and their impact on food quality

This paper reviews the antioxidant properties of tocopherols and ascorbic acid in edible oils, and the impact of interfacial phenomena on their activities in emulsions and the effects of edible oil processing. Tocopherols are the most important natural antioxidants found in vegetable oil-derived foods. These antioxidants can interrupt lipid autoxidation by interfering with either the chain propagation or the decomposition processes. α-Tocopherol at high concentrations inhibits hydroperoxide decomposition but promotes hydroperoxide formation. The effect of antioxidants in inhibiting hydroperoxide decomposition may thus be critical in preserving food quality by reducing rancidity due to aldehyde formation. Ascorbic acid can regenerate α-tocopherol, inactivate metal initiators and reduce hydroperoxides. The activity of natural antioxidants is greatly affected by complex interfacial phenomena in emulsions and multi-component foods. In an oil-in-water emulsion system, the lipophilic antioxidants α-tocopherol and ascorbyl palmitate are more effective than in bulk oil, while the opposite trend is found for the hydrophilic antioxidants Trolox and ascorbic acid. The methodology to evaluate natural antioxidants must be carefully interpreted depending on whether oxidation is carried out in bulk oils or in emulsions, and what method is used to measure lipid oxidation.     

几种天然抗氧化剂对牡丹籽油氧化稳定性的影响

采用Schaal烘箱耐热试验法,以人工合成抗氧化剂二叔丁基羟基甲苯、丁基羟基茴香醚和特丁基对苯二酚等为阳性对照,研究茶多酚、苹果多酚、葡萄多酚、野葡萄多酚、牡丹籽多酚、生育酚、脂溶性迷迭香提取物和水溶性迷迭香提取物等8种天然抗氧化剂及2种增效剂(维生素C和柠檬酸)对牡丹籽油氧化稳定性的影响。研究以过氧化值为评价指标。结果表明,在国家允许添加量范围内,几种天然抗氧化剂均能提高牡丹籽油的氧化稳定性,但单独使用的效果要弱于人工合成抗氧化剂特丁基对苯二酚。其中脂溶性迷迭香提取物抗氧化效果较为理想,与合成抗氧化剂特丁基对苯二酚效果接近。维生素C与柠檬酸是抗氧化剂的良好增效剂,协同抗氧化作用显著,且维生素C的效果优于柠檬酸。复合抗氧化剂的抗氧化效果优于同等质量浓度的单一抗氧化剂,复合添加0.01%脂溶性迷迭香+0.01%茶多酚+0.02%维生素C、0.01%牡丹籽多酚+0.01%苹果多酚+0.02%维生素C和0.01%脂溶性迷迭香+0.01%茶多酚+0.02%柠檬酸均能显著减缓牡丹籽油的氧化速度,可使牡丹籽油的贮藏时间明显延长。     

Heating,microwave and UV irradiation effects on oxidative stability of Sardasht red grape (Vitis vinifera cultiv. Sardasht) seed oil

In the current study, for the first time, the oxidation stability of the extracted edible oil from Sardasht red grape at three different accelerated deteriorative conditions (oven, microwave and ultraviolet (UV) irradiation) was investigated. In this context, the peroxide value (PV), conjugated diene value (CDV), carbonyl value (CV), radical scavenging activity (RSA) and oil/oxidative stability indices, as well as fatty acid composition and total tocopherol content, were evaluated. Sardasht grape seed oil as a rich oil in unsaturated fatty acid (about 87%) contains linoleic acid in terms of the principal fatty acid (70.4 ± 1.8%). The excessive oxidative stability of crude oil can be correlated with the extreme content of natural antioxidants (tocopherols and tocotrienols). The findings showed that Sardasht red grape seed oil could be approached as new source of edible oil with acceptable oxidative stability.     

不同抗氧化剂对红松籽油的氧化抑制作用

目的探究3种抗氧化剂对红松籽油的氧化抑制效果。方法采用石油醚浸提法提取红松籽油,以酸价和过氧化值为评价指标,在加速氧化条件下研究了L-抗坏血酸棕榈酸酯、茶多酚棕榈酸酯、脂溶性迷迭香提取物三种抗氧化剂对红松籽油氧化稳定性的影响。结果 3种抗氧化剂均能不同程度延缓红松籽油氧化酸败进程,抑制效果与抗氧化剂的添加量基本呈正相关; L-抗坏血酸棕榈酸酯(添加量为0.15 g/kg)抑制红松籽油酸价上升的能力最强,而脂溶性迷迭香提取物(添加量为0.60 g/kg)在延缓过氧化物的产生表现出更大优势。结论选择添加0.15 g/kg L-抗坏血酸棕榈酸酯可以更好地用于食用红松籽油的抗氧化。     

葡萄籽油的添加对山核桃油抗氧化能力改善的研究

以山核桃油为主体,通过抗氧化剂BHT、VE、Vc及葡萄籽油的,对山核桃油的氧化稳定性进行研究.研究表明:当葡萄籽油的添加量为6％时,油脂的OSI值最大,相比较0.02％Vc、0.02％ VE及0.02％BHT的抗氧化剂添加对山核桃油抗氧化性影响要大,因此,葡萄籽油可以作为一种新型的天然抗氧化剂,对延长山核桃的货架保质期...     

天然抗氧化剂对葵花籽油抗氧化作用的研究

研究天然维生素E、抗坏血酸、大豆磷脂、β-胡萝卜素、茶多酚、没食子酸、迷迭香提取物七种天然抗氧化剂对葵花籽油的抗氧化活性。研究结果表明:七种天然抗氧化剂对葵花籽油均具有一定的抗氧化活性,其中茶多酚、没食子酸和迷迭香提取物具有较好的抗氧化效果;对没食子酸和迷迭香提取物进行复配得出最佳质量比为4∶1;复合抗氧化剂最佳添加量为0.02%。     

抗坏血酸对大豆蛋白乳液抗氧化稳定性的研究

本试验通过研究抗坏血酸对大豆蛋白乳液体系中油脂的抗氧化作用,明确抗坏血酸作为天然抗氧化剂在乳化体系中的抗氧化机理。本研究采用溶解氧(DO)和顶空氧气消耗法测定大豆蛋白乳液体系在pH 3.0的环境下抗坏血酸对乳液体系氧消耗的影响;验证不同过渡金属Fe~(2+)、Cu~+对抗坏血酸在乳液中清除自由基能力、降解速率、乳液粒径变化和对大豆蛋白乳液氧化稳定性影响。研究表明:通过激光粒度仪分析乳液在储存期间的粒径变化趋势相同,含有抗坏血酸的乳液与对照组没有明显区别,加入金属离子的乳液粒径偏大;15 mmol/L抗坏血酸能够几乎完全消耗乳液体系中溶氧量;抗坏血酸能够在过渡金属Fe~(2+)和Cu~+发生促氧化时通过转移电子和清除体系中的自由基起到抗氧化作用;与对照组相比,Fe~(2+)和Cu~+可加速抗坏血酸降解和氧的消耗,但并没有引起乳液氢过氧化物和己醛含量的快速增加。说明抗坏血酸在大豆蛋白乳液体系中可通过清除自由基和加速乳液体系中氧消耗的多种机制稳定乳液。     

Effect of composition and antioxidants on the oxidative stability of fluid milk supplemented with an algae oil emulsion

The oxidative stability of an algal oil emulsion dispersed in water, or fluid milk of varying fat contents, was assessed from measurements of lipid hydroperoxide and propanal concentration. All of the milk samples, independent of their milk fat content, were stable compared to the aqueous samples. The extent of oxidation was unaffected when sodium azide (200 ppm) was added to inhibit microbial growth. Added iron (100 ppm) accelerated the oxidation rate in the aqueous samples, but had no effect on the milk samples. The antioxidant properties of milk were ascribed to the iron binding of casein. Added protein antioxidants (0.8 wt%) [i.e. sodium caseinate, whey protein isolate (WPI) and thermally denatured WPI] had minimal effects whereas EDTA and ascorbic acid (160 ppm) were effective antioxidants.     

Effect of dietary grape seed extract and Cistus ladanifer L. in combination with vegetable oil supplementation on lamb meat quality

Thirty-six Merino Branco lambs were assigned to six dietary treatments: control diet (C) consisting of 90% dehydrated lucerne and 10% wheat bran; C with 6% of oil blend (CO); C with 2.5% of grape seed extract (GS); GS with 6% of oil blend (GSO); C with 25% of Cistus ladanifer (CL), and CL with 6% of oil blend (CLO). Meat lipid and colour stability was then evaluated during 7days of storage. The effect of inclusion of grape seed extract and C. ladanifer in diets on meat sensory properties was also evaluated. Meat antioxidant potential, determined after oxidation induction by a ferrous/hydrogen peroxide system, decreased with oil supplementation (P<0.001), but inclusion of grape seed extract and C. ladanifer in diets protected the meat against lipid oxidation (P=0.036). Meat colour was not affected by diets. Inclusion of grape seed extract and C. ladanifer in diets did not change the sensory properties of meat.     

迷迭香提取物对紫苏籽油的抗氧化研究

为研究迷迭香提取物能否替代人工合成抗氧化剂,成为紫苏籽油的天然抗氧化剂。以过氧化值和酸价为评价指标,采用Schaal烘箱法研究迷迭香提取物对紫苏籽油的抗氧化作用,并与市面上常用的人工合成抗氧化剂(2,6-二叔丁基对甲苯酚、丁基羟基茴香醚、2-叔丁基对苯二酚)作为对照,测定氧化作用后油样过氧化值及酸价,对比它们在紫苏籽油中的抗氧化效果。采用高效液相色谱法(HPLC)检测紫苏籽油样中鼠尾草酸含量,研究鼠尾草酸含量与紫苏籽油的抗氧化作用的相互影响。结果表明:迷迭香提取物在紫苏籽油中具有良好的抗氧化效果,选择0.08%迷迭香提取物作为在紫苏籽油抗氧化保护的最佳添加量;相比于2,6-二叔丁基对甲苯酚、丁基羟基茴香醚、2-叔丁基对苯二酚,迷迭香提取物为仅次于2-叔丁基对苯二酚的紫苏籽油中最高效的天然抗氧化剂;确定鼠尾草酸是迷迭香提取物中的主要抗氧化有效成分中的一种。     

Effect of endogenous antioxidants of sesame seeds and sesame oil to the thermal stability of edible vegetable oils

Differently processed sesame seeds were used for the preparation of sesamol, seed extract, oil extract or unsaponifiable matter. Analysis of these sesame extracts revealed that dehulling and roasting of seeds had an adverse effect on their lignan and phenolic compounds content. Various concentrations of the extracts were incorporated in vegetable oils and their effectiveness in retarding the oxidative deterioration of oils was evaluated. Additionally, the formation of oxidation products in these oil samples was correlated with their antioxidant activity and their sesamol and phenolic compounds content. Results indicated that decomposition of phenolic compounds present in oil samples induced a significant reduction in their linoleic acid peroxidation inhibition capacity and a corresponding increase in their oxidative rancidity. Sesame seed extract was the most effective in protecting oils from oxidation, suggesting that seed extract, especially the one prepared from coated-unroasted sesame seeds, may have potential application as a source of natural antioxidants in oil industry.     

ANTIOXIDANT ACTIVITY COMPARISON OF THOMPSON GRAPE POMACE EXTRACT, ROSEMARY AND TOCOPHEROLS IN SOYBEAN OIL

The effect of natural antioxidants was tested by oxidative stability index (OSI) in refined soybean oil (RSO) using Rancimat method. Phenolic compounds of Thompson grape pomace were extracted with 95:5 (v : v) ethanol : water. The antioxidant activity of grape pomace extract (GPE) obtained was compared with those of rosemary extract (RE), and tocopherols mix (TM) known as covi-ox T-70. The synergistic effect of citric acid was also evaluated. Results showed a total phenols content of 17.39 mg ( + )-catechin equivalents per g of GPE. Thompson GPE at 0.3 and 0.5% (w/w) exhibited greater antioxidant activity than TM. RSO containing GPE or RE at 0.5% (w/w) showed an OSI higher than 48 h at 110C. Citric acid did not show synergistic effect with GPE. However, a synergistic effect for TM at 0.02% (w/w) with citric acid at 1.0% (w/w) was observed. Citric acid at 2.0% (w/w) with RE at all concentrations tested also displayed synergism.

PRACTICAL APPLICATIONS

Synthetic antioxidants are widely used in the food industry to delay fat oxidation; however, their utilization has been questioned due to toxicology concerns. Researchers have recognized the need to identify new natural antioxidants to use as additives. In this study, we measured total phenolics content of Thompson grape pomace extract (GPE) and found that the antioxidant activity of this extract was stronger than tocopherols from soybean oil. We propose that GPE can have applications as a food antioxidant.     

Impact of antioxidants dispersions on the stability and oxidation of water-in-olive-oil emulsions

Water-in-olive-oil emulsion stability was studied as a function of the composition of the water dispersed phase. In particular, different polyphenolic extracts from natural sources were dispersed in the olive oil and their impact on emulsion kinetic stability and susceptibility to oxidation was evaluated. As natural sources, extra virgin olive oil, olive mill waste and green tea leaves were chosen. To test their impact on emulsion properties, the emulsions were prepared with fixed aqueous phase content. As emulsifiers, a fixed percentage of a mixture Span 80 (sorbitan monoleate)/Tween 80 (polysorbate 80) was used. The effect of the antioxidant dispersion on emulsion oxidation was studied by triggering the oxidation reaction in the oil phase with the lipophilic radical initiator AMVN (2,2-azobis(2,4-dimethylvaleronitrile). Then, the oxidation reaction was followed by using diphenyl-1-pyrenylphosphine, which becomes fluorescent when it is oxidized by hydroperoxides. The impact of antioxidant dispersions on emulsion kinetic stability was studied by UV–Vis turbidity measurements. The oxidation results were correlated to antioxidant extracts oxygen radical adsorption capacity (ORAC) and to emulsion kinetic stability. On the whole, antioxidants dispersions delayed the oxidation reaction to different extents in dependence on their ORAC values and their components amphiphilicity. Remarkably, among the antioxidants tested, the aqueous polyphenol extract from virgin olive oil was the most effective because it protected emulsions both from oxidation and from phase separation. Additionally, from this set of experiments, the primary role of the interfacial properties of olive oil polyphenols was highlighted.     

特丁基对苯二酚与迷迭香提取物对亚麻荠籽油贮藏稳定性的影响

采用Schaal烘箱法与Rancimat法,以过氧化值(POV)及氧化诱导时间为指标,研究特丁基对苯二酚(TBHQ)与迷迭香提取物对亚麻荠籽油贮藏稳定性的影响,分析两种抗氧化剂对加速氧化前后亚麻荠籽油脂肪酸组成的影响,对比分析两种方法在预测亚麻荠籽油货架期方面的准确性。结果表明:亚麻荠籽油氧化稳定性较差,TBHQ与迷迭香提取物可有效延长亚麻荠籽油的贮藏时间,其中0.02% TBHQ与0.04%迷迭香提取物配合使用效果最佳,20℃下预期贮藏时间延长至608 d以上。加速氧化后亚麻荠籽油中多不饱和脂肪酸(PUFA)减少约59.8%,饱和脂肪酸(SFA)与单不饱和脂肪酸(MUFA)分别增多约101.9%与71.8%,添加不同抗氧化剂后亚麻荠籽油脂肪酸组成与烘箱法预测的货架期呈极显著相关性(P<0.01)。Rancimat法与Schaal烘箱法预测货架期存在较大差异,Schaal烘箱法预测亚麻荠籽油货架期具有更高准确性。     

Comparison of soybean oils, gum, and defatted soy flour extract in stabilizing menhaden oil during heating

ABSTRACT:  Capabilities of crude soy oil, degummed oil, gum, and defatted soy flour extract in preventing the oxidation of menhaden oil and its omega-3 fatty acids, DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), during heating were evaluated. The menhaden oil mixed with defatted soy flour extract demonstrated the greatest stability by producing the lowest TBA reactive oxidation products and retaining the highest concentrations of DHA and EPA after heating at 150 °C for 30 min. A range of 62.8% to 71.5% of DHA and 67.7% to 75.9% of EPA remained in the fish oil with defatted soy flour extract, while only 29.9% of DHA and 37.2% of EPA were retained in the fish oil with no addition. Stabilizing capability from highest to lowest was defatted flour extract > gum > degummed oil = crude oil. The defatted flour extract had the highest level of total phenolic content (11.3 μg catechin equivalent/g), while crude oil, degummed oil, and gum contained 7.1, 6.1, and 6.0 μg catechin equivalent/g, respectively. The level of isoflavones in the defatted soy flour extract was 55 mg/g, which was over 100 times higher than in the crude oil or gum. Although isoflavones were not detected in the degummed oil, it contained the highest level of tocopherols (414 μg/g), whereas the lowest level (215 μg/g) was found in the defatted flour extract. The order of free radical scavenging capability measured from high to low was the defatted soy flour extract, crude oil, degummed oil, and gum.     

Fatty acid composition,oxidative stability,antioxidant and antiproliferative properties of selected cold-pressed grape seed oils and flours

Cold-pressed chardonnay, muscadine, ruby red, and concord grape seed oils and their defatted flours were studied for their fatty acid composition, oxidative stability and antioxidant and antiproliferative activities. The phenolic profiles of the seed flours were also measured. The most abundant fatty acid in the oils was linoleic acid, ranging from 66.0 g/100 g of total fatty acids in ruby red seed oil to 75.3 g/100 g of total fatty acids in concord seed oil. The oils were also high in oleic acid and low in saturated fat. Ruby red grape seed oil recorded the highest oxidative stability index of 40 h under the accelerated conditions. Total phenolic content (TPC) was up to 100 times lower in the oils than in the flours. Lutein, zeaxanthin, cryptoxanthin, β-carotene, and α-tocopherol levels were also measured. DPPH radical-scavenging capacity ranged from 0.07 to 2.22 mmol trolox equivalents (TE)/g of oil and 11.8 to 15.0 mmol TE/g of flour. Oxidative stability of menhaden fish oil containing extracts of the seed flours was extended by up to 137%. HPLC analysis was conducted to determine the levels of free soluble, soluble conjugated and insoluble bound phenolics in the seed flours. The phenolic compounds analyzed included catechin, epicatechin, epicatechin gallate, quercetin, gallic acid, and procyanidins B1 and B2. Antiproliferative activity was tested against HT-29 colon cancer cells. All of the seed flours and muscadine seed oil registered significant (P < 0.05) inhibition of cancer cell growth. The results from this study demonstrate the potential of developing value-added uses for these seed oils and flours as dietary sources of natural antioxidants and antiproliferative agents for optimal health.     

马兰头黄酮粗提物对油脂的抗氧化活性研究

目的 分析马兰头黄酮粗提物对油脂的抗氧化性能及体外自由基清除能力。方法 以酸价、过氧化值为指标, 分析2,6二叔丁基对甲酚(butylated hydroxytoluene, BHT)、马兰头黄酮粗提物对花生油、大豆油、猪油的抗酸败氧化性能; 以抗坏血酸为对照, 分析马兰头黄酮粗提物对2,2’-联氮-双-3-乙基苯并噻唑-6-硫酸二铵盐[2,2''-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), ABTS+]自由基的清除能力。结果 马兰头黄酮粗提物可以有效抑制油脂酸价的升高, 可分别将猪油、大豆油的过氧化值超标耐受天数从3、4 d延长至4、5 d, 与BHT作用效果差异不显著(P>0.05), 它对花生油过氧化值的升高抑制作用无实际应用意义; 马兰头黄酮粗提物水溶液对ABTS+自由基清除率最高可达到104.0%±0.9%。结论 马兰头黄酮粗提物具有较好的抑制油脂氧化的作用和很好的自由基清除能力, 具有较好的天然油脂抗氧化剂开发前景。     

Effect of dietary grape seed extract and Cistus ladanifer L. in combination with vegetable oil supplementation on lamb meat quality

Thirty-six Merino Branco lambs were assigned to six dietary treatments: control diet (C) consisting of 90% dehydrated lucerne and 10% wheat bran; C with 6% of oil blend (CO); C with 2.5% of grape seed extract (GS); GS with 6% of oil blend (GSO); C with 25% of Cistus ladanifer (CL), and CL with 6% of oil blend (CLO). Meat lipid and colour stability was then evaluated during 7 days of storage. The effect of inclusion of grape seed extract and C. ladanifer in diets on meat sensory properties was also evaluated. Meat antioxidant potential, determined after oxidation induction by a ferrous/hydrogen peroxide system, decreased with oil supplementation (P < 0.001), but inclusion of grape seed extract and C. ladanifer in diets protected the meat against lipid oxidation (P = 0.036). Meat colour was not affected by diets. Inclusion of grape seed extract and C. ladanifer in diets did not change the sensory properties of meat.     

水酶法油茶籽油的抗氧化剂筛选

采用Schaal 烘箱加速氧化法对比研究4种抗氧化剂及其浓度对油茶籽毛油氧化稳定性的影响,并利用油脂氧化稳定性分析仪测定4种抗氧化剂及其浓度对油样的氧化诱导期的影响。在此基础上,将添加最佳抗氧化剂的油茶籽毛油与空白组(油茶籽毛油)及市售油茶籽油作对比,进行高温连续加热实验并测定油样过氧化值、酸价、p-茴香胺值。结果表明, 0.2 g/kg添加量的叔丁基对苯二酚(TBHQ)抗氧化效果最佳,诱导期最长,为22.76h, 0.2 g/kg添加量的茶多酚棕榈酸酯的抗氧化效果次之,诱导期为15.65 h,但从抗氧化剂的安全性考虑,最终选择茶多酚棕榈酸酯为最佳抗氧化剂。高温连续加热的结果表明, 0.2 g/kg茶多酚棕榈酸酯的添加可有效提高水酶法制备的油茶籽毛油的品质。