Effect of Pretreatments and Air‐Frying,a Novel Technology,on Acrylamide Generation in Fried Potatoes

This paper investigated the effect of air‐frying technology, in combination with a pretreatment based of soaking the samples in different chemical agent solutions (citric acid, glycine, calcium lactate, sodium chloride, or nicotinic acid [vitamin B3]), on the generation of acrylamide in fried potatoes. The influence of reducing sugars on the development of surface's color was also analyzed. The experiments were conducted at 180 °C by means of air‐frying and deep‐oil‐frying, as a reference technology. Based on the evolution of color crust with frying time, it could be concluded that the rate of Maillard reaction decreased as the initial reducing sugars content increased in the raw material, and was also lower for deep‐oil‐frying than for air‐frying regardless of pretreatments applied. Air‐frying reduced acrylamide content by about 90% compared with conventional deep‐oil‐frying without being necessary the application of a pretreatment. However, deep‐oil fried potatoes pretreated with solutions of nicotinic acid, citric acid, glycine at 1%, and NaCl at 2% presented much lower acrylamide levels (up to 80% to 90% reduction) than nonpretreated samples.     

Effects of methyl cellulose-based coating on physiochemical properties and chemical hazards of Chinese fried dough cake during storage

Coating has been used as a practical method to ensure the physiochemical properties and reduce the chemical hazard of fried foods. Methyl cellulose (MC) was used as a coating material to pretreat Chinese fried dough cake (CFDC) before frying. The results showed that the water content, hardness and L* value of the 1% MC coated sample were 31.67%, 848.54 g and 51.62, respectively, at the seventh day at 25 °C. Coating contents 1% MC could reduce the oil content, hardness, and extent of browning and improve the physiochemical properties of CFDC on 7 days of storage. Coating contents 1% MC also reduced the acid value, peroxide value, p-anisidine value, malondialdehyde content, 4-hydroxy-2-(E)-hexenal content, 4-hydroxy-2-(E)-nonenal content, acrylamide content and glycidyl ester content in CFDC on 7 days of storage. Our work contributes to the control of the oil content and chemical hazards for fried food during storage by applying an edible coating.     

抗性淀粉对油炸调理鸡排品质特性的影响

针对油炸过程对调理肉制品质量与安全的影响问题,研究面糊中添加0%～40%的抗性淀粉对油炸调理鸡排品质特性（色泽、脆性、水分和油分含量、丙烯酰胺含量、微观结构及感官评价）的影响,以改善产品质量并实现低脂化。结果表明：添加20%～40%抗性淀粉的鸡排可获得良好的感官可接受性;添加20%抗性淀粉能显著降低油炸调理鸡排的含油量（P＜0.05）,提高油炸后外壳的黄度值,鸡排外壳表现出更好的金黄色,形成密实、连续的面糊微结构,改善外壳脆性,降低油炸过程中丙烯酰胺的生成量,提高产品安全性。因此,添加20%抗性淀粉能更好地降低油炸调理鸡排的含油量,提升产品质量。     

不同马铃薯品种对鲜切油炸薯片中丙烯酰胺的影响

研究11个不同马铃薯品种,在相同的油炸条件下进行鲜切油炸薯片实验,采用液相-质谱联用检测其不同品种鲜切油炸薯片的丙烯酰胺含量,结合品种的还原糖含量,对丙烯酰胺含量进行分析。方法：热烫60s,表面干燥,180℃油炸100s,脱油,样品预处理,待测。结果：在相同油炸实验的基础上,检测出丙烯酰胺含量较低的是D519、陇薯3号、中薯7号、LK99等;丙烯酰胺含量较高的是中薯8号、夏波蒂、中薯3号等,并且丙烯酰胺含量与品种的还原糖含量走向基本相似。     

Formation of trans fatty acids in edible oils during the frying and heating process

To assess an impact of heated edible oils on intake of trans fat, the formations of trans fatty acids (TFAs) in cooking conditions was estimated by a frying and heating model system. For the frying model, sliced raw potatoes (10% of the frying oil (w/w)) were fried in commercially available canola oil at 160, 180 and 200 °C, and the 10 frying cycles were performed. The TFAs contained both in fried potatoes and in frying oils were measured by gas chromatography (GC). Lipids content of raw potatoes was about 0.1% (w/w) and TFAs in the raw potatoes were negligible. On the other hand, fried potatoes contained lipids at the level of 8.8%–9.2% and their fatty acid composition was mostly in correspondence with that of the frying oil. The TFAs amount of potatoes fried by the tenth frying operation was at the level of 0.99–1.05 g/100 g lipids. When 100 g potatoes fried in this process were consumed, the TFAs intake was estimated at less than 0.1 g. After 10 frying operations, TFAs content, acid values and peroxide values of the frying oils were measured and compared with those of corresponding heated canola oils without food. The amounts of trans 18:1 FAs contained both in the frying oil and in heated oil were less than the quantitative limit (0.047 g/100 g oil). The increases of trans 18:2 FAs and trans 18:3 FAs of the used frying oil were 0.02 g/100 and 0.05 g/100 g, respectively, compared with those of the fresh oil. trans 18:2 FAs accumulation in the heated oil was slightly less than that in the frying oil. To elucidate TFAs accumulation in various edible oils during cooking, six kinds of commercially available edible vegetable oils were heated to 180 °C in glass test tubes. Small changes in TFAs amounts were observed after four hours heating. These results suggested that an ordinary frying process using unhydrogenated edible oils has little impact on TFAs intake from edible oils.     

不同烹饪方式处理的鲟鱼肉营养成分和风味比较

为了探究烹饪方式对鲟鱼肉的蛋白质营养价值和风味物质含量的影响,该研究以人工养殖的鲟鱼肉为原料,比较了清蒸和煎炸烹饪方式,对鲟鱼肉的基本营养物质、氨基酸、蛋白质、风味化合物含量,以及氨基酸指数(AAS、EAAI)、蛋白质效价的影响,结果表明,以生鱼肉为对照,清蒸和煎炸使鲟鱼肉的水分含量分别降低了56.41％和43.73％...     

深度油炸对食用油中反式亚油酸含量的影响

选用我国消费最普遍的压榨大豆油和三级浸提大豆油为试验材料,研究不同大豆油经反复油炸对反式亚油酸含量的影响及其含量随油炸次数增加的变化规律。试验分为2组,反复油炸40次,每炸5次采集1次油样,每组测定3个重复。薯条油炸温度为180～185℃,油炸时间为32 h。试验结果表明,压榨大豆油和三级浸提大豆油中总反式亚油酸含量分别为0.18 g/100 g和0.08 g/100 g,前者极显著高于后者(P=0.001),9-cis,12-trans C18:2和9-trans,12-cis C18:2是2种大豆油中主要的反式亚油酸。深度油炸极显著提高大豆油中反式亚油酸含量(P=0.000),在反复油炸40次后,压榨大豆油和三级浸提大豆油中总反式亚油酸含量分别为1.11 g/100 g和0.68 g/100 g,且前者极显著高于后者(P=0.008)。压榨油反式亚油酸经油炸增加幅度高于三级浸提大豆油。     

Effect of an alkaline salt (papad khar) and its substitute (2:1 sodium carbonate:sodium bicarbonate) on acrylamide formation in papads

The formation of acrylamide in papads processed by flame roasting, frying and microwave roasting as a function of the alkaline salt, papad khar and its substitute, 2:1 sodium carbonate:sodium bicarbonate (w/w) at various concentrations was examined. Addition of papad khar and 2:1 sodium carbonate:sodium bicarbonate makes the product alkaline, which is known to be conducive for the formation of acrylamide. While a correlation was found between acrylamide content and pH with respect to fried and flame roasted papads, microwave roasting did not show any acrylamide formation at all the levels of alkaline salts tested in this study. Flame roasting generated higher levels of acrylamide as compared to frying. Use of microwave roasting is therefore recommended as a consumer-friendly, healthy and safe technology for processing papads.     

响应面试验优化胡椒鲜果油炸工艺

为优化胡椒鲜果油炸的工艺,选取油炸温度、油炸时间、料油比为影响因素,以油炸胡椒鲜果中胡椒碱和胡椒精油含量为指标进行研究。在单因素试验的基础上,采用Box-Behnken试验设计构建多项式回归方程的模型,通过响应面分析得到胡椒鲜果最优油炸工艺为：油炸温度92 ℃、油炸时间3 min、料油比1∶1。此条件下胡椒鲜果油炸品质最优,胡椒碱含量预测值为4.28 g/100 g,胡椒精油含量预测值为1.73 mL/100 g,而胡椒碱含量真实值为4.23 g/100 g,胡椒精油含量真实值为1.71 mL/100 g,与预测结果相对偏差仅为1.27%和1.24%。     

Determination of acrylamide in local and commercial cultivar of potatoes from biological farm

This paper reports the results of a preliminary study on the characterization of parameters influencing formation of acrylamide in fried potatoes, from biological cultivation. The formation of acrylamide was investigated in relation to frying in biological extra virgin olive oil and commercial seed oil. Three different cultivars (Rossa di Colfiorito, Quarantina bianca genovese and Kennebec) were chosen. Asparagine, glucose, fructose and sucrose concentrations were determined in potato slice before frying, while acrylamide content was analysed by LC–ESI-MS/MS in the slices fried in seed and extra virgin olive oil. The Kennebec cultivar showed differences in its potential for acrylamide formation, which was primarily related to its relatively high asparagine and reducing sugars contents, respect the other local cultivars (particulary Quarantina). Values of acrylamide below detection limit (LOD) were found in Quarantina bianca genovese cultivar samples fried in extra virgin olive oil and peanuts seed oil and higher in peanuts seed oil fried potatoes of Kennebec cultivar.     

Effects of maltodextrin level,frying temperature and time on the moisture,oil and beta‐carotene contents of vacuum‐fried apricot slices

Response surface methodology was used to investigate the effects of frying temperature, time and maltodextrin (MD) levels on the moisture, oil and beta‐carotene contents of the vacuum‐fried apricot slices. Based on the results, the moisture content of vacuum‐fried apricot slices decreases with increasing frying temperature and frying time. Generally, the oil content of vacuum‐fried apricot slices decreases with decreasing frying temperature and frying time. The beta‐carotene content of vacuum‐fried apricot slices increases with increasing frying temperature. But the trend of increase in the beta‐carotene content of the product with frying temperature was higher at lower MD level. When processing vacuum‐fried apricot slices, a frying temperature of 100 °C, frying time of 72.5 min and an MD level of 70% must be used to achieve a product of acceptable moisture, oil and beta‐carotene contents.     

基于人工神经网络模型预测油炸外裹糊鱼块的丙烯酰胺含量

为实现对油炸外裹糊鱼块的丙烯酰胺含量的预测,采用响应面试验设计收集数据,建立以黄原胶和大豆纤维复配比例、外裹糊鱼块干燥时间、大豆油品质、油炸温度、油炸时间为输入值,油炸外裹糊鱼块的丙烯酰胺含量为输出值的反向传播人工神经网络（back propagation artificial neural network,BP-ANN）,预测外裹糊鱼块深度油炸过程丙烯酰胺含量的变化,并用训练集拟合,测试集评估模型的预测能力。结果显示,黄原胶和大豆纤维复配比例、外裹糊鱼块干燥时间、油炸温度、油炸时间对油炸外裹糊鱼块的丙烯酰胺含量均有显著影响,大豆油品质对油炸外裹糊鱼块中丙烯酰胺含量影响不显著。训练后的BP-ANN模型的相关系数R值为0.997,拟合良好,有很强的逼近能力;模型对新数据预测的误差较小,最大相对误差为5.34%,最小相对误差为0.12%,表明BP-ANN模型能准确预测油炸外裹糊鱼块的丙烯酰胺含量。     

Effect of Microwave Frying on Acrylamide Generation,Mass Transfer,Color, and Texture in French Fries

The objective of this work was to evaluate the effect of microwave power on acrylamide generation, as well as moisture and oil fluxes and quality attributes of microwave-fried potatoes. Concretely, 25 g of potato strips, in 250 mL of fresh oil (at room temperature), were subjected to three different microwave powers (315, 430, and 600 W) in a conventional microwave oven. Microwave frying resulted in an acrylamide reduction ranged from 37 to 83% compared to deep-oil frying. Microwave-fried French fries presented lower moisture and higher fat content than deep-oil fried potatoes. Concretely, microwave-fried potatoes presented values of moisture and texture more similar to potato chips than French fries, nonetheless with lower fat levels (less than 20 g/100 g wb) and acrylamide content (lower than 100 μg/kg wb) at the reference time. This study presents an alternative way of frying to address the production of healthier potato chips.     

即食油炸红娘鱼的加工工艺研究

目的 为研究即食油炸红娘鱼最佳加工工艺,给即食油炸红娘鱼的加工提供科学依据。方法 通过单因素试验和正交试验,探讨油炸条件及玉米淀粉、白醋、碳酸氢钠的添加量对即食油炸红娘鱼品质的影响。结果 影响即食油炸红娘鱼品质的主次因子为油炸条件＞碳酸氢钠＞玉米淀粉＞白醋;即食油炸红娘鱼的最佳最佳配方为玉米淀粉添加3%、白醋添加2%、碳酸氢钠添加0.3%,油炸最适宜条件为在温度170℃下,油炸3min;该工艺加工的即食油炸红娘鱼的理化及安全指标符合水产加工品的国家食品安全标准要求。结论 本研究开发的即食油炸红娘鱼最佳加工工艺,可为即食油炸红娘鱼加工提供生产指导。     

高压静电油炸对花生油及鸡胸肉食用品质的影响

为了研究高压静电油炸对花生油及鸡胸肉食用品质的影响,将鸡胸肉进行高压静电油炸(处理组:4 kV电压条件下,加入1 L花生油,油炸鸡胸肉120 s)和普通油炸(对照组:普通油炸锅,加入1 L花生油,油炸鸡胸肉120 s),测定花生油的过氧化值、酸价、丙二醛含量、色差以及鸡胸肉油炸失重率、质构和感官评定分值等指标。结果表明,高压静电油炸与普通油炸鸡胸肉后,花生油的酸价没有明显差异,但是高压静电油炸后的花生油过氧化值、丙二醛含量均比普通油炸的显著降低(p<0.05),油炸8批次鸡胸肉后,高压静电油炸鸡胸后的花生油亮度值为29.91,显著低于普通油炸鸡胸后花生油的亮度值(p<0.05);高压静电油炸的鸡胸肉失重率明显低于普通油炸后鸡胸肉的失重率(p<0.05),高压静电油炸鸡胸肉的感官评定分值较好。高压静电处理能提高油炸鸡胸肉的食用品质和产率,延缓花生油劣化。     

Effect of frying time on acrylamide content and quality aspects of French fries

The effect of frying time on quality and acrylamide (AA) content of French fried potatoes, obtained simulating home-cooking practices, was studied in order to investigate the optimal conditions to minimize the amount of produced toxicant together with the maintenance of good culinary quality. French fries were obtained from fresh potatoes using a domestic fryer with static basket; a 4:1 oil:product ratio and a fixed initial oil temperature of 180 °C were used. Several batches were fried at different times (3, 4, 5, 6, 7, 8, 9 min). During frying tests the oil, the sticks surface and core temperatures were measured by thermocouples. Analysis of water removal, oil uptake, colour, texture and AA content were carried out on fried final products. AA content increased exponentially increasing the frying time. In our working conditions after around 4 min of frying, when the temperature of potato surface and the oil bath reached, respectively, 120 and 140 °C, the increase of time became a key factor in terms of the quantity of AA and its formation rate. On the basis of colour, oil content and AA level the best culinary product was obtained after 5 min of frying.     

Effects of various cooking conditions on acrylamide formation in rolled patty

In this study on acrylamide formation, the effects of the type of frying oil, frying period and covering with egg during frying of a rolled patty (a traditional Turkish carbohydrate-rich food) were investigated. The differences between frying periods were statistically significant for each oil (p < 0.01). For comparable frying periods, the maximum acrylamide content was found in the rolled patties fried with sunflower oil, and the minimum acrylamide content was found in the rolled patties fried with corn oil. A decrease of 39–65% in acrylamide formation in the rolled patties covered with egg was found for each of the three types of oil. In addition, a high linear correlation (R > 0.90) was found between L (light) values and acrylamide amounts.     

炒制对山核桃仁营养成分的影响

为探明山核桃炒制前后核桃仁营养成分的变化,利用气相色谱、液相色谱和红外光谱法分析检测其相关成分。结果显示：生核桃仁含水量为48.57%,炒熟加工后,含水量可以控制在10% 以内;生山核桃仁的氨基酸总量为111.43mg/g,其中人体必需氨基酸含量为32.32mg/g;炒制后氨基酸总量为74.74mg/g,人体必需氨基酸含量为20.26mg/g,其中,谷氨酸、丝氨酸、精氨酸、酪氨酸、亮氨酸和异亮氨酸等大幅降低;饱和脂肪酸含量增加,红外光谱出现较大差异,生山核桃仁的吸收峰数较少,在3287cm-1 处出现很强的吸收峰,熟核桃仁的吸收峰数量多,3270cm-1 和1650cm-1 处的吸收峰是熟山核桃指纹区。炒制对山核桃仁的多种营养成分有较大影响。     

Optimization of processing conditions to reduce oil uptake and enhance physico-chemical properties of deep fried rice crackers

Physico-chemical properties of fried rice crackers were studied as a function of fish powder content, processing conditions, frying temperature and frying time. The results showed that addition of fish powder content at 5, 10 and 15 g/100 g reduced the oil uptake by approximately 10, 14 and 22 g/100 g (db), respectively in comparison to the control without fish powder. The deep fried rice crackers mixed with fish powder tended to be lower in hardness, lower in expansion ratio and higher in bulk density in comparison to the control sample. The color parameter, L^∗ of fried rice crackers decreased with increase in fish powder content. In contrast, a^∗ and b^∗ values increased with increase in fish powder content. The moisture content of deep fried rice crackers decreased with increase in frying temperature and frying time. The oil uptake in fried rice crackers increased with increase in frying time but decreased with increase in frying temperature. With increase in frying temperature and time, the texture of rice crackers became harder, the bulk density increased, and the expansion ratio decreased. The optimum conditions resulting in desirable physico-chemical properties and minimum oil uptake were rice crackers with fish powder content of 9 g/100 g, fried at a temperature of 220 °C for 60 s.     

EFFECTS OF PREFRY DRYING METHODS ON THE QUALITY OF DEEP FAT FRIED ONION SLICES

Deep fat fried onion slices are used widely as a condiment for hot-dogs and other types of bread and meat combinations in Denmark, Netherlands and Germany. Since there is a consumer demand for food products, high in both sensory and nutritional quality, the effect of prefry drying on the oil content and the color of the fried product was investigated. In order to reduce the oil content in the fried product, raw sliced onions were prefry dried by (1) hot air in a forced air convection oven, (2) microwaving in an oven with a conveyor belt, or (3) freeze dried. For each of the three methods a series of eight batches ranging from 13–30 % dry matter content in the raw onions were obtained. The product that was dried by hot air before frying was lighter than the product prefry dried by microwaving. The product of the freeze dried material was heterogeneous, and the results were excluded. The fried product from dried raw onions, showed the moisture content to be independent of the manipulated dry matter content. The oil content was reduced from about 55% to about 49%, as a result of increasing the dry matter content; however the surface color became darker (L-value was reduced about 6 point).