炒籽温度对压榨亚麻籽油品质的影响

采用不同温度对亚麻籽进行炒籽并压榨制油,对压榨亚麻籽油的感官品质、理化指标及营养成分进行分析,研究炒籽温度对压榨亚麻籽油品质的影响。结果表明:随着炒籽温度的升高,压榨亚麻籽油的气味从坚果芳香过渡到严重焦糊味,色泽加深,在195℃炒籽45 min时形成热榨亚麻籽油特有的浓香型风味;营养成分如VE、总酚以及甾醇含量随炒籽温度升高而逐渐减少,在255℃炒籽45 min时,3种营养成分的损失率分别为75. 7%、76. 5%和88. 9%;酸价、过氧化值、茴香胺值、K232值、K270值随炒籽温度升高而增加,且炒籽温度对压榨亚麻籽油中主要脂肪酸含量有显著影响;适当炒籽对压榨亚麻籽油的氧化稳定性是有利的;高温炒籽压榨亚麻籽油中的营养成分含量与其理化指标密切相关,进而共同影响压榨亚麻籽油的品质。     

压力炒籽技术在生产压榨亚麻籽油中的应用研究

采用常压炒籽、微波和压力炒籽预处理亚麻籽并压榨制油,分析探讨了不同预处理工艺对压榨亚麻籽油的气味、色泽、理化指标、营养成分含量、DPPH自由基清除能力、脂肪酸组成及氧化稳定性的影响。结果表明:未处理及微波、压力炒籽预处理所得压榨亚麻籽油的色泽、酸价和过氧化值等理化指标均优于目前常采用的常压炒籽(170℃,45 min),压力炒籽所得压榨亚麻籽油具有令人愉悦的浓香风味;采用压力炒籽(1. 0 MPa)和微波(亚麻籽水分含量17%,700 W,6 min)所得亚麻籽油的营养品质较好,DPPH自由基清除能力较强,且不同预处理工艺对亚麻籽油脂肪酸组成影响不大;经过常压炒籽(170℃,45 min)得到的压榨亚麻籽油氧化稳定性最好,压力炒籽(1. 0 MPa)其次。因此,利用压力炒籽技术提高压榨亚麻籽油的品质是可行的。     

烘烤对亚麻籽油理化品质、化学组成和抗氧化活性的影响

亚麻籽油因较高的营养价值而受到消费者的青睐,然而,热加工对亚麻籽油品质的影响仍有待阐明。利用热空气对亚麻籽进行烘烤,研究不同烘烤条件对亚麻籽油理化品质（酸价、过氧化值、色泽）、化学组成（共轭二烯、共轭三烯、类胡萝卜素、生育酚、总酚、美拉德反应产物、脂肪酸组成）以及氧化稳定指数、DPPH、ABTS的影响。结果表明：随着烘烤程度增加,亚麻籽油酸价从0.12 mg KOH/100 g增加至1.79 mg KOH/100 g;过氧化值、共轭二烯先增加后减少;类胡萝卜素、总酚、美拉德反应产物、共轭三烯、氧化稳定指数、DPPH以及ABTS均增加,α-亚麻酸含量随烘烤程度增加略微减少。适度烘烤明显改善了亚麻籽油的品质。本研究结果为亚麻籽及亚麻籽油加工提供数据支撑。     

亚麻籽烘烤预处理对亚麻籽油得率 及贮藏稳定性的影响

以亚麻籽油得率为指标,对烘烤预处理亚麻籽工艺进行优化,并研究烘烤预处理对亚麻籽油贮藏稳定性及多酚含量的影响。结果表明：亚麻籽烘烤预处理最佳工艺条件为烘烤时间40 min、烘烤温度100?℃、粉碎粒度0.250 mm（60目）,以此条件下的亚麻籽为原料提取油脂,亚麻籽油得率为44.46%,比未预处理提取的亚麻籽油得率高7.91个百分点,多酚含量高12.61个百分点;贮藏8 d,烘烤预处理提取的亚麻籽油过氧化值、K232、K270的增幅均小于未预处理提取的亚麻籽油。研究表明烘烤预处理不仅能提高亚麻籽油得率,同时可延缓亚麻籽油氧化,进而提高亚麻籽油的贮藏稳定性。     

不同制油方法对青海亚麻籽油品质及货架期的影响

为研究不同制油方法对青海亚麻籽油品质及货架期的影响,对青海亚麻籽分别进行焙炒、烘烤、高压高温湿热、脱胶、真空冷冻干燥前处理,再分别采用螺旋压榨法和液态静压法制油,测定亚麻籽油出油率、过氧化值、酸价、水分及挥发物质量分数、脂肪酸含量、挥发性组分相对含量、总酚含量,并利用Schaal烘箱法建立亚麻籽油氧化动力学模型预测货架期。结果表明,焙炒螺旋压榨法制得的亚麻籽油出油率、总酚含量明显高于其他处理组,过氧化值、酸价、水分及挥发物质量分数均低于其他处理组,模拟预测货架期最长,为353 d。焙炒螺旋压榨法制得的亚麻籽油挥发性组分种类最多,为72 种,其他制油方法制得的亚麻籽油挥发性组分为40～60 种,不同制油方法对亚麻籽油挥发性组分影响明显。此外,亚麻籽油5 种主要脂肪酸中亚麻酸含量最高,为54.71～61.03 g/100 g,不同制油方法对亚麻籽油脂肪酸含量影响不明显。综上,与其他方法相比,焙炒螺旋压榨法制得的亚麻籽油品质较好。     

微波处理对萌动亚麻籽酚类化合物油相迁移的影响

强化亚麻籽中主要酚类化合物内源性合成和油相迁移对提升亚麻籽油氧化稳定性,最大限度地增加α-亚麻酸生物利用率尤为重要。探究了适度萌动(25℃,24h)联合微波处理(700W,1~5min)对压榨亚麻籽油得率和色泽、脂质构型和结晶熔融性、抗氧化活性和氧化稳定性的影响,并研究了亚麻籽中木酚素和游离酚酸的释放及油相迁移规律。结果表明:单一萌动处理(24h)后亚麻籽油得率降低了7.39%(P<0.05),而进一步微波处理后油脂得率增加了29.31%(P<0.05),这主要归因于微波处理破坏了亚麻籽中油脂体膜结构完整性,导致膜内中性脂质外溢、融合和胞外渗透。微波处理1~5min过程中,亚麻籽油中以LnLnLn构型存在的C18∶3ω3质量分数呈现明显升高趋势,同时总磷脂质量摩尔浓度以及磷脂酰乙醇胺、磷脂酰甘油、磷脂酰肌醇占比显著增加(P<0.05),但未明显影响油脂的结晶行为和熔融特性。与未处理组相比,微波处理5min降低了初级和次级氧化产物水平,显著改善了亚麻籽油的氧化稳定性和抗氧化活性(P<0.05),这主要归因于木酚素大分子及其解聚产物开环异落叶松树脂酚二葡萄糖苷,以及游离酚酸香兰素、香草酸和阿魏酸的油相富集。研究阐释了萌动联合微波预处理对亚麻籽油品质特性的影响,旨在为亚麻籽油提质制取和亚麻籽高值化利用提供理论依据。     

制油、吸附工艺以及煎炸实验对亚麻籽油苯并芘的影响研究

针对亚麻籽油加工不当所引起苯并芘超标的不安全性，探讨了制备工艺（籽炒时间和温度）对亚麻籽油中苯并芘含量的影响，同时还考察了混合吸附剂用量、吸附温度、吸附时间对亚麻籽油中苯并芘的去除效果，并采用模拟煎炸实验对亚麻籽油苯并芘形成规律进行研究。结果表明：炒籽温度和时间对亚麻籽油中苯并芘含量有显著影响，随着炒籽温度的升高以及炒籽时间的延长，压榨亚麻籽油中苯并芘含量逐渐增加；另外，混合吸附剂去除亚麻籽油中苯并芘的最佳条件是活性炭和活性白土用量分别为0.3%和2.0%（质量分数）、吸附温度90℃以及吸附时间25 min，苯并芘的去除率高达（90.83±1.06）%。煎炸实验表明：亚麻籽油在180℃下煎炸馒头、豆腐、苹果块及瘦肉等食材12 h后苯并芘含量大幅增加，且煎炸豆腐上升速度最快，上升幅度依次是豆腐>瘦肉>苹果块>馒头。     

浓香亚麻籽油制取工艺设计及生产实践

以30 t/d浓香亚麻籽油加工生产线为例,介绍了亚麻籽经高温烘炒、机械压榨、低温过滤的纯物理方法制取浓香亚麻籽油的工艺过程。概述了主要工序的操作要点及设备选型,分析了影响浓香亚麻籽油质量的关键因素;针对调试中工艺设备存在的问题提出了改进措施。其独特的生产工艺能够使制取的亚麻籽油产生浓郁的香味,最大限度地保留了亚麻籽中天然的活性营养成分和特有的风味。     

压榨亚麻籽油中苯并（a）芘含量超标的防控措施研究

针对亚麻籽油产品质检经常出现苯并(a)芘含量超标问题,通过模拟实验研究了炒籽压榨生产亚麻籽油工艺中炒籽温度、炒籽时间对压榨亚麻籽油中苯并(a)芘含量的影响规律和防控措施。结果表明:炒籽温度超过180℃后,炒籽温度越高,压榨亚麻籽油中苯并(a)芘含量越高,且苯并(a)芘含量超过国标限量值(10μg/kg)的炒籽时间越短,说明炒籽温度过高是出现产品苯并(a)芘含量超标的主要原因;热重分析实验发现亚麻籽在172～174℃有热失重速率谷值,超过该温度后,热失重速率快速升高,说明有机物大量裂解从而快速生成苯并(a)芘;结合炒籽实验和热重分析实验,防控苯并(a)芘含量超标的适宜炒籽温度为不高于170℃; 170℃炒籽75 min压榨得到的亚麻籽油苯并(a)芘含量低于食品安全国家标准限值(10μg/kg),可以作为有效防控苯并(a)芘含量超标的技术措施。     

不同制取方法对亚麻籽油和亚麻籽粕品质影响研究

以未处理和焙炒处理后的亚麻籽为原料,采用溶剂浸提、液压压榨和螺旋压榨三种制油工艺,得到六种亚麻籽油和粕,探讨不同制取方法对亚麻籽油和亚麻籽粕品质的影响。结果表明：焙炒溶剂浸提法样品出油率最高（34.50%）;在三种制油工艺中,焙炒处理后制得的亚麻籽油过氧化值和酸价均高于未处理组,但焙炒前处理可以提高亚麻籽油中总酚和维生素E含量;此外,制取工艺对亚麻籽油的氧化稳定性也有一定影响,其中螺旋压榨油氧化稳定性最好,且同种制取工艺间焙炒前处理可以增强亚麻籽油的氧化稳定性;制取工艺和焙炒前处理对亚麻籽油中亚麻酸含量和不饱和脂肪酸含量影响不显著,但焙炒处理组中的吡嗪、吡咯物质分别比未处理组高5.1%、15.8%、9.3%,未处理组中的醇类物质分别比焙炒处理组高6.1%、11.8%、3.7%。不同制取方法得到的亚麻籽粕中,未处理液压粕粗脂肪、粗蛋白和NSI（氮溶解系数）最高,焙炒螺旋压榨粕木脂素聚合物含量（16.70%）最高,且NSI也处于较高水平（33.13%）;焙炒螺旋亚麻籽粕木脂素聚合物对DPPH、ABTS自由基清除率的半数清除率（IC50）分别为0.49 mg/mL和0.88 mg/mL。本研究结果对亚麻籽油的产业发展和亚麻籽加工副产物的利用提供了参考。     

焙炒处理对不同植物油品质特性的影响北大核心CSCD

为了研究焙炒对植物油品质的影响,以油菜籽、亚麻籽、花生、葵花籽和芝麻为原料,经焙炒处理后采用液压压榨法制油(热榨油),分析植物油的理化指标(酸值、过氧化值、水分及挥发物、色泽)、主体组分(脂肪酸组成及含量、甘三酯组成及含量、挥发性组分)和总酚含量,并与未焙炒处理直接压榨制取的油(冷榨油)作对比。结果表明:热榨油酸值和过氧化值显著高于冷榨油(p<0.05),其中,热榨亚麻籽油酸值(KOH)最高(0.96 mg/g),热榨菜籽油过氧化值最高(1.02 mmol/kg);冷榨油水分及挥发物含量显著高于热榨油(p<0.05),其中冷榨花生油水分及挥发物含量最高(0.16%);热榨油的色泽较冷榨油深,其中热榨菜籽油的色泽最深(R1.1,Y31);焙炒对植物油脂肪酸和甘三酯组成及含量无显著影响(p>0.05);热榨油中醇类、醛类和酸类等挥发性组分较少,但杂环类物质较多;热榨菜籽油、亚麻籽油、花生油、葵花籽油和芝麻油总酚含量分别是其冷榨油的1.38、1.57、1.51、1.80倍和1.27倍。因此,焙炒对植物油品质影响较大,应根据生产需要选择合适的预处理方式。     

HS-SPME-GC-MS-O联用分析不同加工工艺亚麻籽油特征香气成分

以河北省张家口地区不同加工工艺的亚麻籽油为研究对象,采用顶空-固相微萃取法对亚麻籽油香气成分进行萃取分离,借助气相色谱-质谱联用技术分别分析热榨亚麻籽油和冷榨亚麻籽油的挥发性物质构成,并结合气相色谱-嗅觉技术对2?种不同加工工艺的亚麻籽油关键性香气成分进行分析。检测出热榨亚麻籽油特征性香气成分共16?种,包括7?种醛类、4?种杂环类、3?种醇类、1?种酸类、1?种酯类。冷榨亚麻籽油共鉴定出14?种特征性香气成分,包括6?种醛类、4?种醇类、3?种酸类、1?种酯类,冷榨亚麻籽油和热榨亚麻籽油共有香气成分7?种。2,5-二甲基吡嗪、2,3,5-三甲基吡嗪、(E)-2-己烯醛是热榨亚麻籽油特有香气成分,是其烤香味、油脂味的重要来源;乙酸是冷榨亚麻籽油特有香气成分。     

Effect of flaxseed processing on its true metabolizable energy values for adult chicken

The objective of the present experiment was to study the effect of flaxseed processing on nitrogen corrected true metabolizable energy (TME_n) values for adult roosters. Flaxseed was processed as pelleted, autoclaved or microwave roasted. Leghorn roosters were used for the TME determination procedure. The TME_n value of flaxseed batch A, 14.48 MJ kg^?1 DM, was significantly (P < 0.05) increased to 17.89 MJ kg^?1 DM by three‐time repeat‐pelleting, or to 18.07 MJ kg^?1 dry matter (DM) by autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the TME_n value of flaxseed batch B by 22%. The TME_n improvement observed due to processing was accompanied by increased ether extract utilization. The apparent ether extract digestibility of flaxseed batch A, 61.2%, was very significantly (P < 0.01) increased to 81.5 and 83.2% by processing as repeat‐pelleting and autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the apparent digestibility of ether extract for flaxseed batch B from 49.1 to 64.4%. Proper flaxseed processing as pelleting, autoclaving and microwave roasting led to higher TME_n values for Leghorn roosters, mainly as the result of increased ether extract utilization. Copyright © 2004 Society of Chemical Industry     

Effect of processing on the quality of edible argan oil

Sensory quality of edible oil is essential to get the consumer acceptance. Modifications during processing can alter edible oil sensory quality. The storage stability and sensory quality of argan oil prepared from (1) mechanically pressed unroasted kernels, (2) mechanically pressed roasted kernels, (3) hand-pressed roasted kernels, and (4) hand-pressed roasted kernels coming from goat-digested fruits was studied at room temperature and under accelerated conditions (60 °C). The roasting process had a positive effect on storage stability of the resulting oils, while argan oil prepared from mechanically pressed roasted kernels provides the optimum storage stability. Oil from hand-pressed roasted kernels originating from goat-digested fruits was not suitable for human consumption because of the unpleasant taste and odoûr. Only oil from mechanically pressed roasted kernels did not produce negative sensory attributes like fusty or Roquefort cheese.     

Effect of thermal pre-treatment on the phenolic and protein profiles and oil oxidation dynamics of golden flaxseeds

The food industry is interested in the application of thermally pre-treated flaxseeds because the treatment improves their sensory acceptability and reduces anti-nutrient contents. However, it may influence the health benefits of flaxseed compounds. The changes in the phenolic and protein profiles, and in situ oil oxidation dynamics after steaming or roasting of flaxseeds were analysed to study this effect. The results showed that the pre-treatment of flaxseeds did not affect the content of major flaxseed phenolics. Steaming and roasting considerably changed the flaxseed protein profile. The thermally induced protein aggregation and/or cross-linking occurred. The most significant changes were found for the 13 and 53 kDa proteins. Flaxseed roasting deteriorated the oil oxidative stability significantly more than steaming. These changes may decrease the nutritional quality and shelf life of roasted or steamed flaxseeds. They should be monitored when pre-treated flaxseeds are intended to be used as a food ingredient.     

Changes in volatile compounds of peanut oil during the roasting process for production of aromatic roasted peanut oil

The changes in volatile compounds composition of peanut oil during the roasting process of aromatic roasted peanut oil (ARPO) production were investigated. The analyses were performed by gas chromatography-mass spectrometry combined with headspace solid phase microextraction (HS-SPME/GC-MS). Among the volatiles identified in ARPO, the N-heterocyclic chemical class possessed the highest relative percentage area (RPA) 61.68%, followed by O-heterocyclic group with an RPA of 24.57%. Twenty pyrazines were considered to be the key contributors to the intense nutty/roasty flavor typical of ARPO. Compounds that increased significantly in concentration during the roasting process were mainly Maillard reaction products, as well as compounds derived from Strecker degradation and lipid peroxidation. The results clearly showed that the roasting process was necessary to obtain the typical nutty/roasty aroma of ARPO. PRACTICAL APPLICATION: ARPO is the traditional edible oil in China that possesses a characteristic strong nutty and roasty flavor that distinguishes it from other edible vegetable oils. During the production, the roasting process is the crucial factor for the formation of the typical roasted peanut aroma that plays an important role in sensory quality of peanut oil. In our investigation, not only the volatile changes of peanut oil pressed from relevant peanut seeds roasted at different roasting time were determined, but also the contributions of identified volatiles on the typical nutty/roasty flavor of ARPO were discussed. Our work clearly demonstrated the significant effect of roasting process on the typical flavor formation of ARPO. The results are valuable as scientific guidance for the roasting process that better satisfy demands of the peanut oil industries for better flavor.     

Fatty acid and nitrogen utilization of processed flaxseed by adult chickens

The effect of flaxseed processing on the utilization of fatty acids and nitrogen were examined in adult chicken. Two batches (A and B) of flaxseed were processed by autoclaving, pelleting, or microwave roasting. Thirty grams of the ground ingredient was given to fasted Leghorn roosters. The apparent digestibility of total fatty acids of raw flaxseeds A and B were 660 and 490 g kg^?1, respectively. Its improvement (p < 0.05) reached 29% for flaxseed A after three‐times repeated pelleting. Similarly, it was 39% (p < 0.05) for flaxseed B after 4 min of microwave roasting. The improvement in the absorption of major individual fatty acids in flaxseed followed the same pattern as that of total fatty acids. The apparent digestibility of linolenic acid in extruded full‐fat soybean was much higher (p < 0.05) than that in raw flaxseed A, but not that in processed flaxseed A (p > 0.05). Furthermore, roosters given canola seed had significantly higher true nitrogen utilization (p < 0.05) than those fed raw flaxseed A. This difference was reduced or non‐existent (p > 0.05) with processed flaxseed. Proper flaxseed processing effectively increases the utilization of major fatty acids and nitrogen in flaxseed for adult chicken. Copyright © 2005 Society of Chemical Industry     

烘焙工艺及杏仁种皮对杏仁油品质的影响

为探究不同烘焙工艺及杏仁中杏仁种皮的存在对杏仁油理化品质的影响,将带种皮杏仁和去种皮杏仁在130、160、190 ℃烘箱里,分别烘烤5、10、15、20 min,压榨得杏仁油,测定两种杏仁油的酸值、过氧化值、碘值、皂化值、色泽和脂肪酸含量。结果表明:低温130 ℃(5~10 min)、160 ℃(5、10 min)条件下烘焙制备的杏仁油酸值和过氧化值降低,其他理化指标变化不明显,油脂品质提高。随着烘焙温度继续升高,S-AKO(带种皮杏仁油)和N-AKO(去种皮杏仁油)酸值分别上升16.05%和26.76%,N-AKO过氧化值上升18.46%,S-AKO和N-AKO的碘值降低6.56%和10.74%,不饱和脂肪酸含量降低0.93%和0.76%,油脂色泽加深,高温长时间烘焙制备的油脂品质下降。两种杏仁油理化指标对比,S-AKO的品质更佳,杏仁种皮的存在对杏仁油产生有益的影响。此研究结果为加热预处理油料种子制备油脂,保证油脂品质提供理论依据和技术支持。     

Effect of Infrared Heating on the Formation of Sesamol and Quality of Defatted Flours from Sesamum indicum L.

ABSTRACT:  Infrared (IR) heating offers several advantages over conventional heating in terms of heat transfer efficiency, compactness of equipment, and quality of the products. Roasting of sesame seeds degrades the lignan sesamolin to sesamol, which increases the oxidative stability of sesame oil synergistically with tocopherols. IR (near infrared, 1.1 to 1.3 μm, 6 kW power) roasting conditions were optimized for the conversion of sesamolin to sesamol. The resultant oil was evaluated for sesamol and tocopherol content as well as oxidative stability. The defatted flours were evaluated for their nutritional content and functionality. IR roasting of sesame seeds at 200 °C for 30 min increased the efficiency of conversion of sesamolin to sesamol (51% to 82%) compared to conventional heating. The γ-tocopherol content decreased by 17% and 25% in oils treated at 200 and 220 °C for 30 min, respectively. There were no significant differences in the tocopherol content and oxidative stability of the oil. Methionine and cysteine content of the flours remained unchanged due to roasting. The functional properties of defatted flours obtained from either IR roasted or conventionally roasted sesame seeds remained the same.
Practical Applications: Sesame oil is stable to oxidation compared to other vegetable oils. This stability can be attributed to the presence of tocopherols and the formation of sesamol, the thermal degradation product of sesamolin—a lignan present in sesame. Roasting of sesame seeds before oil extraction increases sesamol content which is a more potent antioxidant than the parent molecule. The conversion efficiency of sesamolin to sesamol is increased by 31% by infrared roasting of seeds compared to electric drum roasting. This can be used industrially to obtain roasted oil with greater oxidative stability.