煎炸时间对不同食用油脂品质的影响

目的探讨煎炸时间对不同油脂的热稳定性的影响,通过对不同种油脂观察对比,选择适合煎炸食品使用的油脂。方法以酸价(acid value,AV)、过氧化值(peroxide value,POV)羰基价(carbonyl group value,CGV)为指标,对于不同油脂在不同煎炸时间下,观察油脂理化指标和品质的裂变程度的变化。结果随着煎炸时间的增加,油脂的酸价、过氧化值、羰基价呈现增加趋势。结论 4种油脂对煎炸时间的稳定性为:花生油玉米油大豆油葵花籽油。     

Distribution and retention of phytosterols in frying oils and fried potatoes during repeated deep and pan frying

The retention and distribution of phytosterols in fried oils and French-fries during eight successive pan- and deep-frying sessions of pre-fried potatoes in sunflower oil, palm oil, cottonseed oil, virgin olive oil and a vegetable shortening were evaluated. Phytosterols (β-sitosterol, campesterol, stigmasterol, Δ⁵-avenasterol) were determined in the unsaponifiable fraction of frying oils and lipids extracted from French-fries by GC/FID after derivatization to trimethylsilyl ethers. French-fries were enriched with phytosterols due to the absorption of frying oil, with β-sitosterol predominating in both fried oils and potatoes. The amount of phytosterols decreased during frying, their overall retentions reaching 9.5–22.8% and 29.4–51.2% after eight successive pan- and deep-frying sessions, respectively, while their deterioration was found to be affected by frying time, frying technique, being more prolonged during pan-frying, and by the oils’ unsaturation, being more extended in polyunsaturated oils. Phytosterols were more or less uniformly distributed between the fried oil and the fried potatoes. The phytosterols dietary intake by consuming potatoes fried in the oils tested is discussed.     

Improving the quality of fried oils by using different filter aids

The present study aimed to improve the quality of fried soybean, sunflower, palm and cottonseed oils. Synthetic (Magnesol XL) and natural (diatomaceous earth and kaolin) filter aids were used at various levels (1, 2 and 4%) to adsorb the secondary oxidation products of the oil. The metal patterns (the cations Si, Mg, Ca, Fe, Na, K, Al, Cu, Mn, Zn and the anions CO₃^2?, HCO₃^?, Cl^?, NO₃^?, NO₂^?, SO₄^2?) of Magnesol XL, diatomaceous earth and kaolin were determined. Some physical and chemical properties (refractive index, viscosity, colour, foam height, acid value, peroxide value, thiobarbituric acid value, iodine value, and conjugated diene and polymer contents) of non‐fried, fried and fried–treated soybean, sunflower, palm and cottonseed oils were determined. The frying process was performed at 180 °C ± 5 °C for 12 h continuous heating. The fried oils were treated with the synthetic and natural filter aids at 105 °C for 15 min. The results indicate that Magnesol XL, diatomaceous earth and kaolin contained Si + Mg, Si + Ca and Si + Al, respectively, as the basic metals. Frying soybean, sunflower, palm and cottonseed oils led to significant increases in refractive index, colour, foam height, viscosity, acid value, peroxide value, TBA value, conjugated diene and polymer contents and decrease in iodine value. Treatment of fried oils with Magnesol XL, diatomaceous earth and kaolin at the 1, 2 and 4% levels greatly improved the quality of fried oils. These findings indicate the high efficiency of the filter aids used in the present study in adsorbing the products of oil degradation. Copyright © 2006 Society of Chemical Industry     

煎炸用油品质变化及测定方法研究进展

阐述近年来煎炸油脂的应用和煎炸油脂的品质变化及其测定方法研究进展,着重说明煎炸后酸值、过氧化值、碘值、羰基价、极性组分、脂肪酸组成、皂化值、烯烃的变化规律,并对国内外的测定煎炸油品质的新方法做了介绍。     

油炸工艺对油炸鸡腿品质和安全性的影响

研究油炸温度-油炸时间-新旧油比例对油炸鸡腿丙烯酰胺含量和品质特性的影响,优化油炸工艺,控制丙烯酰胺生成量,改善产品质量。分别测定了在150、160、170℃油炸11、12、13min过程中鸡腿丙烯酰胺生成量和品质的变化。结果显示:使用新油油炸温度为150℃油炸11min时水分含量最高,脂肪含量最低;油炸用油为新旧油比例1:1;油炸温度为150℃,油炸12min时油炸鸡腿的外观金黄;使用新油在150℃下油炸11min时油炸鸡腿鸡皮中丙烯酰胺含量最低;使用新旧混合油油炸温度为150℃油炸12min时油炸鸡腿鸡肉中丙烯酰胺含量最低。结合油炸鸡腿的品质和安全指标综合考虑后确定油炸鸡腿的最佳油炸工艺参数为:新旧油比例为1:0,油炸温度为150℃,油炸时间为11min。      

油炸工艺对油炸鸡腿品质和安全性的影响

研究油炸温度-油炸时间-新旧油比例对油炸鸡腿丙烯酰胺含量和品质特性的影响,优化油炸工艺,控制丙烯酰胺生成量,改善产品质量分别测定了在150、160、170℃油炸11、12、13min过程中鸡腿丙烯酰胺生成量和品质的变化.结果显示:使用新油油炸温度为150℃油炸11 min时水分含量最高,脂肪含量最低;油炸用油为新旧油比例1∶1;油炸温度为150℃,油炸12min时油炸鸡腿的外观金黄;使用新油在150℃下油炸11 min时油炸鸡腿鸡皮中丙烯酰胺含量最低;使用新旧混合油油炸温度为150℃油炸12min时油炸鸡腿鸡肉中丙烯酰胺含量最低结合油炸鸡腿的品质和安全指标综合考虑后确定油炸鸡腿的最佳油炸工艺参数为:新旧油比例为1∶0,油炸温度为150℃,油炸时间为11 min.     

深度油炸过程煎炸油的氧化及其对油炸外裹糊鱼块品质的影响

目的 探究深度油炸过程煎炸油的氧化,并进一步研究煎炸油氧化对油炸外裹糊鱼块品质的影响。方法 分别采用棕榈油、大豆油、葵花籽油、小麦胚油在150、160、170、180、190℃下油炸外裹糊鱼块,测定煎炸油的酸价、过氧化值、黏度、介电常数以及油炸外裹糊鱼块外壳的水分含量、油脂含量、表面色度。结果 随着油炸温度的升高,煎炸油的游离脂肪酸含量增加,导致煎炸油的酸价、黏度和介电常数升高,过氧化值呈现波动下降的趋势;油炸外裹糊鱼块的水分含量逐渐减少,油脂含量逐渐增加,L*和b*呈递减趋势、a*呈递增趋势,且使用4种煎炸油的各项指标存在明显差异。结论 煎炸油的油炸温度和不饱和脂肪酸含量显著影响了煎炸油的氧化,导致外裹糊鱼块深度油炸过程中水分蒸发和油脂吸收有明显差异,最终影响了油炸外裹糊鱼块的品质。     

热处理方式对豆腐品质特性的影响

为了确定豆腐的最佳预处理条件和参数,对其在电磁炉煮制、蒸制、过热蒸汽、油炸、微波短时加热处理过程中的品质变化进行了研究。探索在不同加热方式处理下豆腐中心温度的变化规律。结果表明:在微波加热处理时豆腐的中心温度升高速度最快,加热过程中大量的水分快速蒸发,4 min处理后质量损失达76. 97%;油炸处理对豆腐的色泽变化影响较大;微波加热对豆腐的质构品质影响较大;经热处理豆腐切面观察表明,蒸煮对豆腐结构影响最小,豆腐切面孔隙最小。综合上述指标分析得出:微波处理时间90 s、蒸制8 min、水煮4 min、160℃过热蒸汽处理8 min、150℃油炸5 min时豆腐的综合品质较好。     

不同热处理压榨油茶籽油的风味差异研究

研究了油茶籽制取浓香油茶籽油的最佳热处理方式。采用顶空固相微萃取-气质联用法（HS-SPME-GC-MS）结合电子鼻技术对6种不同热处理（蒸炒、微波加热、冷榨以及80~90 ℃下炒料10~20 min）后的压榨油茶籽油挥发性风味成分进行鉴定和研究。结果表明：6种热处理压榨油茶籽油的挥发性风味成分主要为醛类、醇类物质（共占74%以上）,其中,己醛、庚醛、辛醛、壬醛、癸醛、（Z）-2-癸烯醛和正辛醇是6种不同热处理压榨油茶籽油的共同风味成分,正辛醇是初次从油茶籽油风味物质中鉴定的1种油茶籽原生态风味成分;油茶籽经传统蒸炒处理或 80~90 ℃下炒料20 min处理会使压榨油茶籽油中产生大量的糠醛或糠醛衍生物,从而影响油茶籽油的食用安全和存储安全,而冷榨、微波加热以及80~90 ℃下炒料10~15 min处理的压榨油茶籽油中没有这些物质;在80~90 ℃下炒料15 min是获得浓香油茶籽油的最佳热处理方式,在此条件下获得的压榨油茶籽油具有风味浓郁而柔和、兼具食用安全和生产安全等优势。     

硅胶C935对煎炸油品质改良处理工艺研究

硅胶C935是一种品性优良的煎炸油处理剂,经它处理后,煎炸油的酸价、极性化合物含量、色价、发烟量都有明显降低,油脂的品质得到改善;它还可以明显降低油炸食品的吸油率;通过正交实验确定C935对煎炸油最佳的处理工艺参数为:C935添加量2.0%,处理温度85℃,处理时间15min.     

Reviewing the effects of vacuum frying on frying medium and fried foods properties

Vacuum frying (VF) is a process developed at a pressure lower than atmospheric pressure, in which lower temperatures are employed to remove moisture from the food and reduce the oil content in the final product. Diverse studies have been published for VF or assisted with microwave and ultrasound, facing the challenges of accomplishing the physical and sensory properties appreciated in fried products. The studied matrices under VF include mainly vegetable origin foods (apple, banana, carrot, donuts, kiwi, mushroom, pea, pear, potato and sweet potato) and some animal origin products (chicken nuggets, fish fillets and surimi products). This review aimed to show recent and relevant findings of the application of VF, analysing both the effects on the frying medium and the impact on the fried foods. The inclusion of microwave and ultrasound technologies aids in the obtention of high-quality products in terms of sensory and textural attributes, oil content as well as reduced oil degradation. This technique may provide safer and stable fried foods with lower oil content aiding in improving the diet of consumers and reducing production costs.     

TGP在煎炸油质量评价中的应用研究

现有煎炸油质量评价指标存在特征指标专一性不强、适用范围有限等缺陷。对煎炸油中极性组分与TGP相关性进行研究,结果表明,极性组分与TGP随煎炸时间的延长呈线性增加关系。通过试验得出多次使用的煎炸老油中TGP含量远高于新鲜煎炸油,用TGP含量评价煎炸油质量具有可行性。相较PCs指标,TGP的稳定性更能使其客观反应油脂的新鲜程度。     

煎炸不同食物对煎炸油品质的影响

为了探究不同食物对煎炸油劣变程度的影响,将大豆油在180℃条件下煎炸鸡胸肉和土豆,连续煎炸7 d,每天煎炸6 h;分别检测煎炸油的酸值、羰基值、总极性成分含量和脂肪酸组成及含量,分析不同食物对煎炸油品质影响的差异性和相关性,并讨论不同食物成分对煎炸油理化指标影响的原因。结果显示:煎炸鸡胸肉的煎炸油的酸值(KOH)、羰基值、总极性成分含量分别上升到3.14 mg/g、66.69 meq/kg、40.02%,各指标之间呈极显著相关性(P0.01),相关系数大于0.95;煎炸土豆的煎炸油的酸值(KOH)、羰基值、总极性成分含量分别上升到1.48 mg/g、192 meq/kg、47.16%,各指标之间呈极显著相关性(P0.01),相关系数大于0.86;煎炸鸡胸肉的煎炸油饱和脂肪酸、不饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸呈极显著相关性(P0.01),煎炸土豆的煎炸油上述脂肪酸呈显著相关性(P0.05)。煎炸不同食物对煎炸油品质产生不同的影响。     

不同煎炸用油制备河豚鱼汤挥发性风味成分的差异性

采用顶空固相微萃取-气相色谱-质谱联用技术分析不同煎炸用油制备的河豚鱼汤中挥发性风味物质,利用相对气味活度值结合主成分分析确定其特征风味成分.结果表明,不同煎炸用油制备的河豚鱼汤中挥发性风味物质种类与相对含量差别较大,5种不同鱼汤中共检出69种挥发性物质,其中清汤,猪油、大豆油、花生油、橄榄油煎炸后熬煮制得鱼汤分别检测...     

基于同步荧光光谱法对食用油和煎炸油鉴别研究

快速鉴别食用油和煎炸油,选用市售大豆油、花生油、调和油以及不同煎炸条件下煎炸后的大豆油、花生油和调和油作为试验样品,采用Gray Eclipse荧光光度计对样品进行扫描处理,运用SPSS 16.0软件和Origin 8.0软件对样品的同步荧光光谱数据进行分析。结果表明,食用油煎炸后,荧光峰位置发生红移;与原油相比,煎炸后的大豆油与调和油的荧光峰强度降低,花生油的荧光强度在300~400之间波动;同一煎炸温度下,随煎炸时长的增加,煎炸油的荧光峰向波长增加的方向移动;同一煎炸时长下,随煎炸温度的增加,与原油相比,煎炸油发生红移的距离增大。判别分析对食用油和煎炸油的正确判别率为100%。可见利用同步荧光光谱法结合化学计量学方法可以有效区分食用油和不同煎炸条件下的煎炸油。     

Effects of frying parameters on the colour development of fried potatoes

The effects of frying time and temperature on the colour development of potatoes during frying was studied. Potato disks 0.025 m in diameter and 0.005 m thick were used. Sunflower oil was used as a frying medium at temperatures 150 °C, 160°C, 170°C and 180°C. Colour parameters of Hunter L and b values followed first-order reaction kinetics during frying. The temperature dependence of the rate constants for Hunter L and b values showed good agreement with Arrhenius relation, the activation energies, Ea, being equal to 22.67 kcal/mol and 17.13 kcal/mol, respectively. Hunter a value increased as frying time and/or temperature increased. A multiple regression equation was developed for total colour change as a function of time and temperature. The increase in time and temperature increased total colour change. Received: 22 October 1999     

Influences of ultrasonic-assisted frying on the flavor characteristics of fried meatballs

In order to investigate the influences of ultrasonic-assisted frying on the flavor characteristics of fried meatballs, different ultrasound powers (0, 200, 400, 600 and 800 W) were applied during frying (12 min, 160 °C). The thiobarbituric acid reactive substances (TBARS), free fatty acids (FFAs), free amino acids (FAAs), 5′-ribonucleotides and electronic nose data were measured. Results demonstrated that ultrasonic treatment significantly increased TBARS and decreased ∑FFAs (p < 0.05), thus accelerating FFAs oxidation and further promoting volatiles generation. Meanwhile, ultrasonic-assisted frying increased the contents of 7 FAAs including Lys, Glu, Gly, Ala, Tyr, Ser and Cys in all ultrasonic groups and had a positive effect on nucleotides formation within 400 W. These results were further confirmed by electronic nose analysis. The current study shows that ultrasonic-assisted frying could be a potential approach to improve the overall flavor of fried meatballs.Industrial relevanceUltrasound, as an emerging and green technology, is a safety and effective tool for food processing industry. It is considered as an excellent alternative in meat processing. Ultrasonic-assisted frying has been scarcely applied in the processing of meatballs. This study demonstrated that the flavor quality of meatballs improved a lot by ultrasonic treatment, which could be an ideal reference to optimize its application in meat industry.