稻米油调和油煎炸应用研究

通过与棕榈油对比180℃下炸制薯片以及评估薯片感官喜好度、质构、口感及粘牙性等差异来评价稻米油调和油的煎炸应用性能。结果表明:采用稻米油调和油煎炸的薯片中多不饱和脂肪酸含量显著高于棕榈油(P<0.05),且其薯片的整体感官喜好度、质构口感、酥脆度、粘牙喜好度,均显著优于棕榈油薯片(P<0.05)。在加速氧化条件下,采用稻米油调和油炸制的薯片的酸价、过氧化值均与棕榈油炸制的薯片无显著性差异(P>0.05),且远低于GB 16565-2003的规定。在加速存储过程中,谷维素却得到了很好的保留。总之,稻米油调和油具有良好的煎炸性能。     

Effects of variety and stage of fruit ripeness on the physicochemical and sensory characteristics of deep‐fat‐fried banana chips

The quality of banana chips prepared from two different varieties of banana, Pisang Abu and Pisang Nangka, at the ‘green’ and ‘trace of yellow’ stages of ripeness was studied. The fruits were peeled, sliced to a thickness of 2 mm and deep‐fat fried in refined, bleached and deodorised (RBD) palm olein at 180 ± 5 °C for 3 min. The quality parameters determined for fresh bananas were total soluble solids, pH, acidity, carbohydrate, sugar content, fat, protein, moisture content, ash, fibre, colour and fruit firmness. The results showed that Abu had a higher carbohydrate content than Nangka at both stages of ripeness before frying. No sucrose was detected in Nangka. The quality parameters determined after deep‐fat frying were moisture content, water activity, oil absorption, crispness and sensory evaluation. The moisture content and water activity of Abu chips were lower than those of Nangka chips. The texture of chips prepared from Abu at stage ‘green’ showed more crispness than the other three samples. Sensory evaluation showed that chips prepared from Abu at both stages of ripeness presented better colour, flavour, odour, texture and overall acceptability than those prepared from Nangka. Based on the matrix of correlation coefficients, fresh bananas with higher fruit firmness and carbohydrate content gave banana chips with higher crispness and oil absorption. © 2001 Society of Chemical Industry     

Quality changes of edible oils during vacuum and atmospheric frying of potato chips

Demand for safe and nutritionally rich fried products is gaining a momentum among consumers, leading to the increased consumption of vacuum fried products. The impact of vacuum frying (VF)(110 °C, 40 kPa) on chemical composition of food, fatty acid profile, microstructure, oxidative stability and sensory attributes was assessed and differentiated with that of atmospheric frying(AF) (180 °C). The potato slices were fried in mustard and soyabean oil used repetitively for 25 h. The oil content of VF potato chips was lower (15.18%) than AF chips (18.98%), however water loss in AF chips was higher than VF chips by 1.63-fold. VF significantly prevented the PUFA degradation, minimizes transfatty acid (TFA) formation and maintain a low C18:2/C16:0 ratio as compared to AF. VF Chips fried in soyabean oil show an increase in TFA content from 2.15 to 2.63% and a decrease in PUFA from 51.57 to 45.16% as compared to AF chips where TFA content increased from 2.15 to 3.72% and PUFA shows a higher reduction from 51.57 to 37.69% at the end of 25 h of frying. This indicate that in AF, oil is safe for use upto 10 cycles of frying, while as in VF, the same oil can be used for upto 40 cycles of frying without quality deteoriation. Sensorial analysis revealed that VF chips retain a better colour, taste and flavour but were less crispy than that of AF chips. These findings validate the application of vacuum frying technology for the production of high-quality foods with lesser degradation of frying oil.Industrial relevanceFood manufacturers are now impelled by the health-conscious consumer base for the production of healthy food products. The toxic effect of foods fried in degraded oils on human health is now widely known and thus the production of safe fried foods is the need of hour globally. In this context, vacuum frying is the most feasible approach for the production of quality fried products retaining the natural colour, flavour, sensory and nutritional properties better than that of atmospheric frying. Vacuum frying causes the least degradation of fatty acid of the frying oil and the fried potatoes, producing healthy potato chips. Therefore, the oil used for vacuum frying have a greater shelf life and oxidative stability than atmospheric frying. However, the higher installation cost of vacuum fryer still limits its use in the street fried food market, where degradation of oil is more likely. Thus, for its widespread commercialisation in developing countries, steps should be taken both by government and manufacturing companies to reduce the installation costs.     

Effect of superheated steam prefrying treatment on the quality of potato chips

Superheated steam drying (SSD) was used as a prefrying treatment prior to deep‐fat frying for potato slices. The effect of SSD at 130, 150 or 180 °C and steam velocity of 2.0 m s^?1 on the fat uptake, colour and texture of fried potato chips was evaluated; microstructure and degree of starch gelatinization were also evaluated to help explain the fat uptake results. SSD and frying yielded potato chips with the fat content from 0.263 ± 0.002 to 0.304 ± 0.002 kg kg^?1 (d.b.), while frying without SSD led to chips with the fat content as high as 0.359 ± 0.003 kg kg^?1 (d.b.). SSD did not promote starch gelatinization. Lower fat uptake was correlated to modified surface structure and lower moisture content of potato slices prior to frying. Frying with/without SSD pretreatment yielded potato chips of similar hardness, crispness and lightness. On the other hand, SSD significantly increased redness and yellowness of the fried chips.     

响应面法优化低脂甘薯脆片加工工艺

以红心甘薯为原料,优化低脂甘薯片生产过程中漂烫、热风干燥、油炸等关键工艺参数,以产品含油率和色差(L*值和b*值)为评价指标,并通过响应面优化确定最优的低脂甘薯片生产工艺。结果表明,较优漂烫工艺条件为:漂烫温度70 ℃,漂烫时间7 min;较优的热风干燥工艺条件为:热风干燥温度70 ℃,热风干燥时间40 min;最优油炸工艺条件为:预油炸温度149 ℃,预油炸时间98 s,二次油炸温度190 ℃,在该条件下测定含油率的平均值达(17.1±0.2)%。该工艺条件下制得的甘薯脆片含油率低于同类产品,外观亮黄,无焦糊现象。     

Technological evaluation of new cultivars for potato chips manufacturing

Potato tubers of cvs. Condor, Diamont, Baraka, Mondial and Draga were used to produce chips of 1.0 mm slice thickness using an industrial slicer. Half of the slices quantity was immediately blanched in water at 100°C for approximately 5 min. Frying was carried out at 165–170°C in cotton seed oil. Both cvs. Diamont and Condor were the best varieties in the nutritional composition, since they contained the highest content of total solids (24.2 and 22.8%), crude protein (10.9 and 10.2%), total free amino acids (270 and 246 μmol/g DM), ascorbic acid (1.5 and 1.4 mg/100 g DM) and digested protein (49.8 and 49.6% for pepsin enzyme as well as 76.0 and 78.3% for trypsin enzyme). In contrast, they contained the lowest level of reducing sugars i.e. 0.8 and 0.9%, respectively. The same both varieties produced the maximum final yield of chips from both unblanched and blanched slices (50.0 and 47.4% as well as 48.9 and 45.8%, respectively) with the lowest final oil content i.e. <42%. Slightly differences in the final moisture content of chips were noticed. Blanching before frying led to a decrease in the final oil content of chips produced from all potato varieties. Sensory evaluation of the produced chips revealed that the favourable chips with the best quality attributes i.e. lighter and uniform in colour, lower final oil content, natural odour, more crisp and better in taste can be produced by using slices from cvs. Condor and Diamont. Furthermore, blanching before frying reduced significantly the oil content of chips and improved both colour and texture (more crispness) of the produced chips.     

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.     

Two-stage frying process for high-quality sweet-potato chips

Vacuum frying (1.33 kPa), with the aid of a de-oiling mechanism, was used to produce low-fat sweet potato chips. The kinetics of oil absorption and oil distribution in the chips (total, internal, and surface oil content) was studied so that effectiveness of the de-oiling system could be established. Product quality attributes (PQAs) such as moisture content, oil content, diameter shrinkage, and thickness expansion, as well as, color, texture, bulk density, true density, and porosity of chips fried at different temperatures (120, 130, and 140 °C) was performed to evaluate the effect of process temperature on the product.     

微波生产低油马铃薯片的工艺条件的探讨

通过单因素试验,对利用微波生产低油马铃薯片工艺中影响产品脆度、色泽和含油量的一些因素进行了探讨。结果表明:利用微波生产马铃薯片可以降低薯片含油量到20%以下;干燥前食盐水溶液浸泡处理(1.5%～2.0%食盐水溶液浸泡5min)和涂油前用豆奶粉裹衣处理,均能降低产品的含油量,提高马铃薯片的脆度;同时,适量的豆奶粉裹衣处理,能赋予产品良好的色泽,豆奶粉的用量6%比较适宜;冷冻处理能加深产品的色泽,但是对产品的脆度和含油量的影响不大。     

低温真空油炸粉葛片工艺优化及其品质分析

为实现粉葛的全质化利用,本文采用低温真空油炸工艺制备粉葛片。在单因素实验基础上通过正交试验优化了低温真空油炸粉葛片的制备工艺。结果表明,最优工艺为粉葛片厚度2 mm,油炸温度105℃,油炸时间35 min,漂烫时间3 min。在最优条件下粉葛片脆性值为989.35 g,脂肪含量为22.95%。此外,还比较了不同工艺制备的粉葛片品质。漂烫、冷冻处理后低温真空油炸粉葛片的脂肪含量较低,脆性值较高,而通过漂烫冷冻常规油炸所得粉葛片含水量（1.71%）和脆性值（597.54 g）最低,脂肪含量达62.24%。未漂烫粉葛片常规油炸后脂肪含量显著高于低温真空油炸所得粉葛片（P<0.05）,而脆性值无显著性差异（P>0.05）。油炸粉葛片香气物质以氮氧化合物、硫化物和有机硫化物为主,但是不同油炸所得粉葛片香味有明显差异。经油炸后粉葛片表面蜂窝状结构消失,通过漂烫冷冻低温真空油炸的粉葛片表面有少许孔洞,而在未冷冻的葛根片表面形成一层凝胶层。     

微波膨化甘薯鱼糜脆片的加工工艺优化

以甘薯泥和三文鱼加工副产物制作而成的鱼糜为主要加工原料,采用微波膨化技术制作甘薯鱼糜脆片,以产品的感官品质和质构特性为评价指标,通过单因素实验,研究微波膨化条件、植物油添加量、糯米粉添加量、小苏打与碳酸氢铵添加量及其添加比例对甘薯鱼糜脆片的品质影响,并通过正交试验确定最佳工艺。结果表明:以鱼糜与甘薯泥总质量为基准,添加植物油4%,糯米粉30%,小苏打和碳酸氢铵以2:1比例添加1.0%,在500 W功率下微波膨化120 s,制得的甘薯鱼糜脆片感官得分为(86.5±1.01)分,硬度值与脆度值分别为(7654.125±123.521) g、(8165.365±105.347) g,外观完整,色泽均匀,口感酥脆。     

茶多酚在油炸过程中对马铃薯片品质及其贮藏稳定性的影响

以感官品质、质构特性、理化特性、风味特性以及丙烯酰胺含量为指标,研究茶多酚在连续油炸过程中对马铃薯片品质的影响,并进一步探究茶多酚对马铃薯片贮藏稳定性的影响。结果表明,茶多酚对连续油炸过程中马铃薯片感官品质及硬度值的下降具有抑制作用;茶多酚对连续油炸过程中马铃薯片水分含量和含油率的增加具有明显的抑制作用,并且降低了薯片的含油率,茶多酚组T₂₄批次的马铃薯片含油率为41.96%±2.00%,显著低于空白组的46.29%±1.06%(P<0.05)。同时,与空白对照组相比,茶多酚抑制了马铃薯片劣变风味的产生,明显抑制了马铃薯片中有害物丙烯酰胺的生成。此外,茶多酚能够增加油炸马铃薯片的贮藏稳定性,平均货架期能够延长8 d。初步分析,茶多酚在油炸过程中对油脂品质的保护作用是其能够提高马铃薯片品质的重要原因。     

非油炸甘薯大豆脆片的研究

以甘薯、大豆、玉米淀粉为主要原料,通过原料配比、辊扎成型、烘烤条件等方面的比较试验,对非油炸甘薯大豆脆片的生产工艺进行了研究,并初步确定了产品的生产工艺及配方。以本工艺生产的产品具有色泽浅黄、有甘薯大豆烘烤香味,结构松脆,产品水分含量3.6%、脂肪含量8.0%、蛋白质含量1.8%。     

远红外油炸对鸡肉品质的影响

主要研究了远红外辅助油炸和普通热传导式油炸两种方式对鸡肉油炸品质的影响。实验选用新鲜市售鸡胸肉,油炸温度为(165±2)℃,考察其在70～110s油炸时间段内色泽、质构、中心温度、水分含量、含油量和失重率的变化规律。结果表明:除鸡肉的硬度值外,不同的油炸方式和油炸时间对鸡肉各项测定指标均影响显著(P<0.05)。以普通热传导式油炸为对照,远红外油炸的鸡肉明度(L*)降低,红度(a*)和黄度(b*)增加;硬度值变化不显著,弹性值略有增加;内部的温度上升均匀、波动小;最高含油量降低33%,最大失重率降低10.21%。因此,远红外油炸促进了鸡肉色泽的变化,使内部受热均匀,降低了含油量,减少油炸损失,对油炸品质的提高起到积极作用。     

Effects of combined pretreatments on drying kinetics and quality of potato chips undergoing low-pressure superheated steam drying

Due to an increasing demand from health-conscious consumers more attention has been placed on investigating alternative techniques to replace conventional deep-fat frying to produce health-friendly snack products including potato chips. Recently, low-pressure superheated steam drying (LPSSD) has proved to have potential to produce fat-free potato chips if performed in combination with appropriate pre-drying treatments. In this study, the influences of various pretreatments and drying temperature on the LPSSD drying kinetics and quality parameters of dried potato chips were investigated. LPSSD of potato chips underwent various combined pretreatments, i.e., (a) blanching, (b) combined blanching and freezing, (c) blanching followed by immersion in glycerol solution and then freezing, and (d) combined blanching, immersion in monoglyceride solution and freezing, were carried out at different drying temperatures (70, 80, and 90 °C) at an absolute pressure of 7 kPa. The quality of the dried chips was then evaluated in terms of colors, texture (hardness, toughness and crispness) and microstructure. In terms of the drying behavior and the dried product quality, LPSSD at 90 °C with combined blanching and freezing pretreatments was proposed as the most favorable conditions for drying potato chips.     

基于均匀设计和主成分分析的甘薯薯片油炸工艺优化

为优化甘薯薯片油炸工艺,采用单因素和均匀设计相结合进行试验,对均匀设计试验数据进行多元回归分析。单因素试验表明:切片厚度、预干燥阶段和油炸阶段对含油量、L*值和b*值有较大影响;均匀设计逐步回归分析表明:油炸时间对含油量影响显著(P=0.011),食盐水质量分数对含水量影响显著(P=0.022),油炸温度和油炸时间对L*值影响极显著(P=0.001),预干燥时间和油炸时间对b*值影响显著,食盐水浸泡时间、食盐水质量分数、预干燥温度、预干燥时间和切片厚度对脆度的影响符合二次多项式回归模型(P=0.001);指标主成分分析表明:提取2个主成分能解释87.4%的指标信息,达到指标降维目的;岭回归分析建立了综合得分回归模型,相关系数R为0.997,能很好地拟合产品的综合得分;偏最小二乘法回归分析预测最佳综合评分工艺参数为切片厚度2 mm、热烫时间1 min、质量分数1%食盐水浸泡20 min、预干燥温度60℃、预干燥时间70 min、油炸温度150℃、油炸时间1 min,验证综合评分为0.89,综合评分高于均匀设计试验组最高值0.86。优化工艺所得产品具有含油量低、颜色和脆度俱佳等特点,相关模型具有良好的预测能力。     

Structure and Texture Properties of Fried Potato Products

Potatoes are the fourth most important vegetable crop in the world, and in 2003, it was a 2.7 billion dollar business in the US alone. Nearly one-third of the potato production is processed into par-fried frozen potatoes and fried chips (snacks). Frying imparts desirable taste and textural properties to these products, the latter described usually by the sensorial term crispness. Frying is reviewed as a structuring process, and methodologies to determine texture in fried potato products are discussed. It is demonstrated that the histological and microstructural heterogeneity of potato tubers have hampered clear interpretation of experimental data and a rigorous modeling of frying. Moisture uptake during post-frying is critical in the loss of crispness (limpness) of fries and in softening of potato chips. Methods to evaluate these changes and alternatives to prolong the shelf life are discussed.     

Application of Vacuum Frying as a Furan and Acrylamide Mitigation Technology in Potato Chips

Consumers like fried snacks, and taste, color, and texture are key aspects in their preference. However, during frying of foods some toxic compounds, such as furan and acrylamide, are produced. The objective of this work was to mitigate furan and acrylamide formation in potato chips, without affecting their main quality attributes, by using vacuum frying. To accomplish this purpose, potato slices were fried at atmospheric (P _abs 29.92 inHg) and vacuum conditions (P _abs 3.00 inHg), using equivalent thermal driving forces (T _{water boiling point} ? T _oil = 50, 60, or 70 °C). Furan and acrylamide concentration, oil content, and texture of both atmospheric and vacuum-fried samples were determined. Vacuum-fried potato chips showed reductions of about 81, 58, and 28% of furan, acrylamide, and oil content, respectively, when compared to their atmospheric counterparts. Additionally, the texture was not affected (p > 0.05) by changes in the pressure during frying. Results clearly showed that vacuum frying is an effective technology for furan and acrylamide mitigation in potato chips, since it reduces the content of both contaminants and preserves the quality attributes of fried snacks.     

常压油炸马铃薯脆片加工工艺参数的研究

以适于油炸加工的马铃薯品种--大西洋为原料,研究了切片厚度、坯料烘干时间(含水量)、被膜剂浓度、油炸时间、油炸温度对常压油炸马铃薯脆片品质的影响,确定了常压油炸马铃薯脆片的加工工艺参数,即马铃薯切片厚度为2.0mm,油炸坯料于50℃温度下烘80min,含水量控制在60%左右,油炸前用0.8%的CMC-Na溶液被膜,在180℃油温下炸制2min。     

Structure and Texture Properties of Fried Potato Products

Potatoes are the fourth most important vegetable crop in the world, and in 2003, it was a 2.7 billion dollar business in the US alone. Nearly one-third of the potato production is processed into par-fried frozen potatoes and fried chips (snacks). Frying imparts desirable taste and textural properties to these products, the latter described usually by the sensorial term crispness. Frying is reviewed as a structuring process, and methodologies to determine texture in fried potato products are discussed. It is demonstrated that the histological and microstructural heterogeneity of potato tubers have hampered clear interpretation of experimental data and a rigorous modeling of frying. Moisture uptake during post-frying is critical in the loss of crispness (limpness) of fries and in softening of potato chips. Methods to evaluate these changes and alternatives to prolong the shelf life are discussed.