葡萄糖/天冬酰胺低湿模拟体系中丙烯酰胺产生机理研究

采用葡萄糖/天冬酰胺低湿模拟体系,系统研究反应条件对丙烯酰胺形成的影响。在单因素试验的基础上,选取加热温度、加热时间、天冬酰胺添加量、葡萄糖加入量4个因素,进行响应面优化分析。结果表明:加热温度和天冬酰胺添加量对丙烯酰胺的产生量影响显著。葡萄糖和天冬酰胺添加量分别为1.2 mmol,丙烯酰胺最大产生量条件为:加热温度200°C,加热时间6.5 min,丙烯酰胺的最大理论生成量为674.0 nmol。     

Asn/Glc模拟体系中丙烯酰胺形成规律的研究

美拉德反应目前被认为是形成丙烯酰胺的重要途径。本文对葡萄糖和天冬酰胺模拟体系中丙烯酰胺的形成规律进行研究。结果表明,反应温度和时间对丙烯酰胺的产生量具有很大的影响,即随着温度和时间的增加,丙烯酰胺的产生量也相应增加;研究还发现,丙烯酰胺与天冬酰胺、吸光度之间呈线性关系,与葡萄糖、果糖也呈一定的相关性。     

果糖/天冬酰胺模拟体系中丙烯酰胺产生机理的研究

系统研究了果糖/天冬酰胺模拟体系中丙烯酰胺形成规律。在单因素实验的基础上,选取加热温度、加热时间、天冬酰胺添加量、果糖加入量4个因素,进行响应面优化分析。结果表明:果糖的添加量、加热温度和天冬酰胺的添加量对丙烯酰胺的产生影响显著。丙烯酰胺最大产生量的条件为:加热温度200℃,加热时间6.0 min,果糖添加量1.2 mmol,天冬酰胺添加量1.2 mmol。丙烯酰胺的生成量为1640.0 nmol。     

葡萄糖/天冬酰氨模拟体系丙烯酰胺形成

采用葡萄糖与天冬酰氨的模拟体系来研究反应条件对丙烯酰胺的产生的影响.以色度、198 nm下紫外吸光度和丙烯酰胺含量为指标,考察反应温度、时间、初始pH值和摩尔配比对丙烯酰胺形成的影响.结果表明反应温度是影响丙烯酰胺形成关键因素,葡萄糖比天冬酰胺对模拟体系的丙烯酰胺形成影响要大,初始pH值在8时,丙烯酰胺形成最大.     

温度和pH值对美拉德模拟体系中丙烯酰胺形成的影响

丙烯酰胺(AA)是一种对人体具有潜在致癌作用的食品污染物之一,研究AA的形成规律对控制其形成具有一定的理论和实践意义。通过对AA形成的模拟体系研究发现,温度和反应液初始pH值对AA的形成具有一定的贡献。加热处理过程中,反应温度对AA形成影响显著(P<0.05),随着反应温度的增加模拟体系中AA含量相应增加。pH值对模拟体系中AA形成的影响比较复杂,随着反应液初始pH值的增加,模拟体系中AA含量也相应增加,但是当pH值达到10时,AA的含量反而下降,当pH值为8时,产生最高含量的AA,因此可以通过控制体系的温度和pH值,来减少AA的形成。     

葡萄糖-天门冬酰胺体系中丙烯酰胺的生成规律研究

对葡萄糖-天门冬酰胺(Glu-Asn)模拟体系中丙烯酰胺的生成规律进行了研究。探讨了氨基酸种类、反应底物摩尔比例、加热时间、加热温度和pH等单因素对丙烯酰胺生成量的影响。选取加热时间、加热温度和pH进行正交试验优化得到丙烯酰胺的最大生成量条件:0.1mol/L的等摩尔比Glu-Asn体系溶液于180℃(油浴)、pH 8.0(PBS)的条件下加热30min,丙烯酰胺的生成量为(164.80±13.26)nmol,在此基础上进行进一步的抑制作用研究。     

绿原酸影响氨基酸消减丙烯酰胺的研究

绿原酸是马铃薯中的主要酚酸。试验将丙烯酰胺分别与7种氨基酸进行高温加工处理,研究添加绿原酸对体系中丙烯酰胺消减的影响。结果表明,绿原酸促进丙烯酰胺的消减。加入绿原酸在160℃反应30 min后,丙烯酰胺消减率显著提高,为9.58%(天冬酰胺)～33.46%(半胱氨酸)。采用甘氨酸/丙烯酰胺体系,进一步研究绿原酸添加量、加热温度和时间对丙烯酰胺消减的影响,发现丙烯酰胺消减率随绿原酸添加量、加热温度的增加和时间的延长而提高。绿原酸与丙烯酰胺物质的量比25∶1,180℃反应60 min后,丙烯酰胺消减率达到66.9%。     

添加甘氨酸对天冬酰胺/葡萄糖模拟体系中丙烯酰胺形成的抑制作用

美拉德反应目前被认为是形成丙烯酰胺的重要途径,极探讨了甘氨酸在葡萄糖/天冬酰胺模拟体系中抑制丙烯酰胺形成的规律。模拟体系分别在90、100、110、120℃下反应4h,丙烯酰胺的生成、褐变度的增加、产物的减少以及对天冬酰胺和甘氨酸降解动力学的分析表明,甘氨酸的添加能够显著降低美拉德反应生成的丙烯酰胺,且在该反应体系中甘氨酸与天冬酰胺之间存在竞争关系。     

一种用于筛选丙烯酰胺抑制剂的模型的建立

本文建立了模拟丙烯酰胺形成的化学模型和食品模型,分别研究了150℃和170℃条件下2～10min范围内不同加热时间对上述模型中丙烯酰胺产生量及产物颜色的影响。确定的化学模型条件为：0．050g天冬酰胺、0．060g葡萄糖及3mL去离子水,于不锈钢密封管中170℃油浴加热5min;食品模型条件为：约2mm厚薯片,在蒸馏水或抑制剂溶液中浸泡3min后,于170℃油炸5min。     

丙烯酰胺天冬酰胺/葡萄糖低湿模式反应体系条件优化

试验主要研究了天冬酰胺/葡萄糖低湿模拟体系中丙烯酰胺生成及提取条件,对影响体系丙烯酰胺生成的反应条件和丙烯酰胺提取条件进行了优化。结果表明,天冬酰胺/葡萄糖低湿模拟反应体系中丙烯酰胺最佳反应条件为:40μL葡萄糖(0.25 mol/L)和40μL天冬酰胺(0.25 mol/L)加入40μL蒸馏水在160℃反应20 min,反应结束后向体系中加入1 mL蒸馏水超声重复提取2次,每次5 min,提取温度30℃。在上述条件下体系中生成和提取的丙烯酰胺量达到最大。     

Study on formation of acrylamide in asparagine–sugar microwave heating systems using UPLC-MS/MS analytical method

Microwave heating can be regarded as a possible way to produce a considerable amount of acrylamide. The present study investigated the formation of acrylamide in asparagine–glucose, asparagine–fructose and asparagine–sucrose microwave heating systems by the response surface methodology (RSM) and the orthogonal array methodology (OAM). The acrylamide content was rapidly quantified by a validated ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. Results of RSM study indicated that in the asparagine–glucose system, the acrylamide content increased in the combined condition of high temperature accompanying with short heating time (>190 °C, <20 min) or low temperature accompanying with long heating time (<180 °C, >30 min). In the asparagine–fructose system, the similar conclusion was made in the combined condition of high temperature accompanying with short heating time (>175 °C, <20 min) or low temperature accompanying with long heating time (<170 °C, >25 min). In the asparagine–sucrose system, the amount of acrylamide enhanced with the increase of both heating temperature and heating time. The fitted mathematic models were successfully applied to the quantification of acrylamide formation when the heating temperature and heating time fell into the ranges of 120–240 °C and 5–35 min simultaneously. OAM study showed that acrylamide is readily formed via heating binary precursors 5 min at 180 °C in the asparagine–glucose and asparagine–fructose systems. However, acrylamide is readily generated when the binary precursors are heated 15 min at 180 °C in the asparagine–sucrose system.     

A comparative study of acrylamide formation induced by microwave and conventional heating methods

ABSTRACT:  In this study, the formation of acrylamide upon treatment with microwave and conventional heating, boiling, or frying was investigated in both Asn/Fru and Asn/Glc model systems and in potato chips. Acrylamide levels were analyzed by HPLC method, which was confirmed by HPLC-MS/MS. Present results in model systems showed that pH value had a complex influence on the formation of acrylamide in the 2 systems during both microwaving (600 W) and boiling (120 ± 1 ^oC). At pH < 8.0, acrylamide content increased with increasing the pH value, reaching the maximum at pH 8.0 whereas acrylamide content decreased with the increase of pH. Regardless of pH and heating methods, acrylamide content generally increased with increasing treatment time. Surprisingly, all present results showed that microwave heating not only induced acrylamide formation in the 2 model systems but also facilitated more acrylamide to be formed as compared to the boiling method at identical pH and treatment time. At pH 4.0, 8.0, and 10.0, the larger the microwave power, the more the acrylamide content. Consistent with the above observation, treatment of potato chips with microwave heating for 2.5 to 3.5 min in the range 550 to 750 W similarly resulted in acrylamide formation. The highest acrylamide content was formed by 750 W microwave treatment as 0.897 ± 0.099 mg/kg, which was significantly higher than that produced by traditional frying (180 ± 1^oC), 0.645 ± 0.035 mg/kg ( P < 0.05).     

Acrylamide formation in low-fat potato snacks and its correlation with colour development.

A recipe and technological process for the production of low-fat potato snacks (7% fat) was developed at the Institute of Food Technology of Plant Origin (Agricultural University of Poznan) using a combination of extrusion and a roasting process. Due to the character of the product, the level of acrylamide was analysed. At the same time, the influence of temperature and time of heating on acrylamide levels were monitored, as well as the correlation between colour development and acrylamide content. The level of acrylamide in low-fat potato snacks was 489 +/- 26 microg kg(-1), which is comparable to French fries, crackers and cookies but almost three times less than in potato chips, as analysed by other authors. It was also shown that temperature and heating time have a significant influence on acrylamide formation, with temperature having a stronger effect than time. Measurement of colour and acrylamide content at different temperatures and roasting times showed that there is a substantial correlation between lightness (L*), redness (a*), yellowness (b*) and acrylamide concentration as a function of time: r(2) = -0.995, r(2) = 0.996, r(2) = 0.998, respectively. Graduated increases in roasting temperature showed a correlation between lightness (L*) or redness (a*) and acrylamide concentration: r(2) = -0.947 and r(2) = 0.968. Yellowness (b*) was not correlated with acrylamide content as a function of temperature.     

黑枸杞花青素抑制曲奇饼干中丙烯酰胺效果的研究

研究黑枸杞花青素对食品体系中丙烯酰胺的抑制效果。采用响应面分析优化焙烤温度、焙烤时间以及花青素在曲奇饼干中的添加量,获得抑制丙烯酰胺产生的最佳条件。结果显示,花青素可以有效抑制曲奇饼干中丙烯酰胺的产生;当焙烤温度为185℃,焙烤时间为12 min,花青素添加量为0.32 g/kg时,在此条件下丙烯酰胺抑制率为69.34%。研究表明:温度、时间、花青素添加量均对丙烯酰胺的产生具有显著影响,建立的二阶多项式模型准确性高,可以有效预测产品中丙烯酰胺的抑制效果。     

Calcium regulating growth and GABA metabolism pathways in germinating soybean (Glycine max L.) under NaCl stress

In this study, modelling of time/temperature-depending acrylamide formation in red bell peppers was performed. The data collected were analysed using a central composite design and response surface modelling, to optimize the thermal treatment (temperature and time of heating) of red bell pepper, in order to find the condition of lower acrylamide production maintaining sufficient status of processed vegetable. Using this approach, the acrylamide content in studied samples was in the range of 47 ± 12.03 and 10,616 ± 189.47 ng/g at temperature/time condition between 170 and 240 °C, respectively, 4–46 min. The calculated equation of acrylamide formation in grilled red bell pepper revealed that the minimum acrylamide formation is at the lowest exposure times, between 4 and 15 min. Also, the lower the cooking temperature is, the lower the acrylamide formation is. Moreover, the presented model enables the prediction of the acrylamide level at various temperature/time conditions of red bell pepper thermal treatment.     

油炸马铃薯片中丙烯酰胺形成的影响因素的研究

丙烯酰胺是富含碳水化合物和氨基酸的食品经高温加热发生美拉德反应而产生的,但有关影响丙烯酰胺形成因素的研究却较少。探讨了油炸温度、原料中还原糖和氨基酸含量、鲜薯切片浸泡液的柠檬酸浓度、油炸前薯片的水分含量及抗氧化剂和油的使用时间对丙烯酰胺形成的影响。结果表明:原料中还原糖和氨基酸含量越高,产品中生成的丙烯酰胺就越多;油炸温度越高,产品中丙烯酰胺含量也相应越高;浸泡液柠檬酸浓度越大,产品中丙烯酰胺含量越低;而随着半成品中含水量的降低,产品中的丙烯酰胺含量也逐渐减少;在油中添加不同浓度的BHT和TBHQ以及采用使用时间不同的油,对加工出来的薯片之间丙烯酰胺含量没有显著的影响。     

Quality and safety driven optimal operation of deep-fat frying of potato chips

Increasing oil temperature and heating duration in deep-fat frying of potato chips can improve textural quality but worsen the chemical safety of acrylamide formation. Optimal design of this complex process is formulated as a non-linear constrained optimization problem where the objective is to compute the oil temperature profile that guarantees the desired final moisture content while minimizing final acrylamide content subject to operating constraints and the process dynamics. The process dynamics uses a multicomponent and multiphase transport model in the potato as a porous medium taken from literature. Results show that five different heating zones offer a good compromise between process duration (shorter the better) and safety in terms of lower acrylamide formation. A short, high temperature zone at the beginning with a progressive decrease in zone temperatures was found to be the optimal design. The multi-zone optimal operating conditions show significant advantages over nominal constant temperature processes, opening new avenues for optimization.     

食品加工条件对于产品反式脂肪酸含量的影响

选取食用油-橄榄油、大豆油和棕榈油,模拟日常烹饪体系,采用气相色谱法分析加热和煎炸情况下食用油中反式脂肪酸的种类和含量。试验结果表明,食用油单独加热情况下,加热温度、时间和循环加热次数影响食用油中反式脂肪酸的种类和含量,高温、长时间加热、反复加热均会使反式脂肪酸的含量有所增加。煎炸情况下,在一定温度范围和加热时间内,食用油的反式脂肪酸的含量增加并不明显。因此,普通的烹饪过程中,应注意减少高温加热时间、避免食用油的反复使用。     

Reducing Acrylamide in Fried Snack Products by Adding Amino Acids

ABSTRACT: The aims of this study were to develop commercial methods for reducing the acrylamide content in processed foods and apply them to commercial snacks. The formation of acrylamide in fried foods was found to depend on the composition of raw materials as well as the frying time and temperature. In potato chips, acrylamide was rapidly formed at over 160°C, with the amount proportional to the heating duration and temperature. Free amino acids were used to reduce acrylamide, with lysine, glycine, and cysteine having the greatest effects in the aqueous system. Lysine and glycine were effective at inhibiting the formation of acrylamide in wheat-flour snacks. In potato snacks, the addition of 0.5% glycine to pallets reduced acrylamide by more than 70%. Soaking potato slices in a 3% solution of either lysine or glycine reduced the formation of acrylamide by more than 80% in potato chips fried for 1.5 min at 185°C. These results indicate that the addition of certain amino acids by soaking the uncooked products in appropriate solutions is an effective way of reducing acrylamide in processed foods.