血浆蛋白乳化物在低脂乳化肠中的应用

血浆蛋白、大豆油和水经斩拌可形成高浓度乳化物。以该乳化物作为脂肪替代品加工乳化肠,研究了不同脂肪替代率(25%、50%、75%、100%)下乳化肠的感官品质、化学组成、脂肪酸组成、持水能力、颜色和质构特性。结果表明:随脂肪替代率增大,乳化肠水分、蛋白质、灰分含量逐渐升高,脂肪含量逐渐降低;饱和脂肪酸、单不饱和脂肪酸含量逐渐降低,多不饱和脂肪酸含量逐渐升高;持水能力逐渐下降;50%、75%及100%替代组乳化肠L*,a*,b*值显著高于对照组(p<0.05);在质构特性上,25%、50%和75%替代组乳化肠硬度、弹性、粘聚性、咀嚼性、回复性均显著高于对照组(p<0.05),粘着性显著低于对照组(p<0.05)。脂肪替代比例为25%、50%、75%的乳化肠在感官上与对照组差别不大。替代率为100%时,乳化肠中血浆蛋白粉的特征腥味明显,可接受程度降低。      

Konjac gel as pork backfat replacer in dry fermented sausages: processing and quality characteristics

The effect of replacing animal fat (0%, 50% and 80% of pork backfat) by an equal proportion of konjac gel, on processing and quality characteristics of reduced and low-fat dry fermented sausage was studied. Weight loss, pH, and water activity of the sausage were affected (P<0.05) by fat reduction and processing time. Low lipid oxidation levels were observed during processing time irrespective of the dry sausage formulation. The fat content for normal-fat (NF), reduced-fat (RF) and low-fat (LF) sausages was 29.96%, 19.69% and 13.79%, respectively. This means an energy reduction of about 14.8% for RF and 24.5% for LF. As the fat content decreases there is an increase (P<0.05) in hardness and chewiness and a decrease (P<0.05) in cohesiveness. No differences were appreciated (P>0.05) in the presence of microorganisms as a result of the reformulation. The sensory panel considered that NF and RF products had acceptable sensory characteristics.     

膜分离技术在植物油脂精炼中应用进展

目前,植物油精炼一般采用传统化学精炼或物理精炼方法,二者都存在一定局限性;而膜分离技术是一种有效、低成本工艺技术,其在油脂加工业应用已日益受到人们重视。该文综述膜分离技术在植物油精炼中应用研究进展。     

Effects of replacing pork backfat with emulsified vegetable oil on fatty acid composition and quality of UK-style sausages

Rapeseed and sunflower oil were used to replace pork backfat in UK-style sausages by incorporating the oils as pre-formed emulsions. Replacing the pork backfat emulsion with rapeseed emulsion at total fat content of about 12%, reduced total saturated fatty acid (SFA) composition from 38% to 14% (4.5 to 1.8 g/100 g), increased monounsaturated fatty acid (MUFA) composition from 45% to 59% and increased polyunsaturated fatty acid (PUFA) composition from 15% to 25%. Partial replacement of pork backfat with rapeseed at a fat content of about 20% reduced SFA from 38% to 24% (7.2 to 4.8 g/100 g). There were no significant differences in eating quality and overall liking other than slight differences in the attributes ‘firmness’ and ‘particle size’. Improvement in the fatty acid composition was achieved without adversely affecting colour shelf life or lipid oxidation. The study suggests that a substantial reduction in SFA can be achieved by incorporating ‘healthy’ oils in UK-style sausages without adversely affecting eating quality or shelf life.     

动植物油脂不皂化物测定方法研究

通过对国内外动植物油脂不皂化物检测方法比较,考察不同检测方法对动植物油脂不皂化物测定结果影响,并分析造成结果差异原因。结果表明,美国油脂化学家学会(AOCS)两项方法AOCS Ca 6a-40(09)和AOCS Ca 6b-53(09)较IS03596:2000和IS018609:2000方法适用范围广,可实现对不皂化物含量较高动植物油脂检测,且萃取过程充分、技术路线严谨、测定结果准确可靠。     

Physical and sensory characteristics of pork sausages from enzymatically modified blends of lard and rapeseed oil during storage

Physical and sensory characteristic of pork sausages produced from enzymatic interesterified blends of lard and rapeseed oil during storage were evaluated. All three enzymatic interesterified blends (IE90, IE70 and IE50) had ratios of unsaturated to saturated fatty acids within the range of 1.47–2.84 which is favourable for cardiovascular disease risk reduction. Blends of IE90 and IE70 were found to have suitable solid fat content, melting and crystallization profile suitable for sausages production. Sausages were produced from blends of IE90 and IE70 with different muscle types (musculus longissimus dorsi and musculus sternomandibularis) and processing conditions such as cooling rates and final processing temperature. Cooling rate was found to have no significant (P > 0.05) effect on hardness of the sausages throughout storage. Both musculus longissimus dorsi and high final processing temperature of 20 °C increased the hardness of the sausages during storage. In terms of fat particle size distribution, it was found that sausages IE70 had significantly (P < 0.05) lower amount of small fat particles (<4 μm) and higher amount of big fat particles (4–500 μm). This is in agreement with the findings on softer texture of sausages IE70. All the sausages produced from interesterified blends of lard and rapeseed oil had no apparent fat excretion and were rated as having acceptable sensory attributes as compared to reference sausage which was produced from pure lard.     

部分变性植物油作苎麻油剂应用研究

将植物油磺化变性取代部分乳化剂,则解决自乳化油剂的成本问题.研究了植物油种类、硫酸变性工艺、辅助乳化剂等因素对油剂性能的影响,结果表明:渍(浓硫酸)为2%(对植物油体积),2%体积的浓硫酸以约0.5滴/秒的速度滴加到植物油中进行部分变性、再加入辅助复合乳化剂可得到自乳化油剂.该油剂克服了传统油剂所存在的问题,生产成本低,稳定性好,可在较低温度下实现给油,具有良好的推广应用前景.     

植物油作为食用油和工业润滑油氧化稳定性评价的研究进展

植物油因较高的营养价值和良好的润滑性可作为食用油和工业润滑油。旨在为评价不同使用功能的植物油的氧化稳定性提供参考,从食用油和工业润滑油两方面综述了植物油氧化稳定性的检测方法,讨论比较检测方法的适用性、优缺点以及植物油在不同行业中氧化稳定性的评价指标和改善方式的差异。作为食用油,过氧化值、酸值和茴香胺值等理化指标以及氧化诱导时间是常用的评价指标;而对于工业润滑油,酸值、运动黏度和起始氧化温度是常用的评价指标。植物油的使用功能不同,其氧化稳定性研究的侧重点不同。针对指标要求的差异性选择合适的研究方法或者联合应用多个方法,对于最大程度发挥植物油的价值有重要意义。     

An optimized procedure for detection of genetically modified DNA in refined vegetable oils

Food Science and Biotechnology - In this study, the amplifiable DNA from refined vegetable oils was isolated by using commercial DNA extraction kits based on the CTAB method in combination with...     

Effect of fat level and partial replacement of pork backfat with olive oil on processing and quality characteristics of fermented sausages

Six formulations of dry fermented sausages were produced in three replications with three initial fat levels (30, 20 and 10%) and two levels (0 and 20%) of pork backfat replacing olive oil. After 4 weeks of fermentation and ripening the fat content of the treatments with 30, 20 and 10% fat level ranged from 38.86 to 43.60%, 25.56 to 26.86% and 19.01 to 20.14%, respectively. Fat level affected (P<0.05) the weight losses, the chemical composition, the Gram −ve bacterial count, the lightness, the texture and the appearance of fermented sausages. Replacing 20% of pork backfat by olive oil affected (P<0.05) the lightness and yellowness of sausages. Fat-reduced sausages without olive oil and low-fat sausages with olive oil had the highest score for odour and taste. However, the appearance of fat-reduced sausages was just acceptable while that of low-fat sausages was unacceptable, because the surface was intensively wrinkled and case hardening had developed. Further research is needed to improve the appearance of these sausages.     

谷维素对3种食用植物油的抗氧化效果研究

从米糠油皂脚中提取纯化谷维素,按不同比例添加到大豆油、菜籽油和油茶籽油中,分别采用Schaal烘箱法和油脂氧化分析仪对3种植物油氧化稳定性进行测定,同时考察在植物油氧化过程中,谷维素对其脂肪酸组成的影响,并与常见的油脂抗氧化剂进行对比。结果表明:油脂中分别添加0.1%和0.5%谷维素均对大豆油、菜籽油和油茶籽油的氧化诱导期具有延长作用,其中对油茶籽油的作用最显著;在Schaal烘箱实验中,谷维素能够有效延缓大豆油和油茶籽油过氧化值的升高,并且对油中多不饱和脂肪酸的氧化有抑制作用,但对菜籽油的抗氧化作用不显著。     

植物油中甾醇的高温稳定性研究

研究了6种植物油(玉米油、甾醇强化玉米油、大豆油、花生油、葵花籽油、橄榄油)中甾醇在高温条件下的热稳定性。使用气相色谱-质谱联用技术检测了植物油中3种主要甾醇(菜油甾醇、豆甾醇、β-谷甾醇)含量,并测定了油脂酸值随加热时间的变化。结果表明:总甾醇含量最高的是甾醇强化玉米油,达到7.82 mg/g,橄榄油中甾醇含量最低,为0.63 mg/g,β-谷甾醇在总甾醇中比例最高;高温加热(180℃)条件下,植物油中甾醇稳定性较强,但加热时间过长,仍会导致部分甾醇降解;加热过程中,植物油的酸值均呈上升趋势。因此,植物油中甾醇在高温条件下的降解应引起重视。     

植物油中甾醇烯类物质的检测研究

建立了GC-MS测定植物油中4种甾醇烯类物质的方法。样品用石油醚提取,经硅胶柱净化,HP-5毛细管柱(5%苯基聚硅氧烷,30 m)分离,质谱检测采用SIM模式。在0.062 5～1.0 mg/L的质量浓度范围内,峰面积与质量浓度呈良好线性,线性相关系数(r)大于0.99。在特级初榨橄榄油中添加0.025、0.050 mg/kg和0.100 mg/kg水平的甾醇烯类物质,平均加标回收率为78.6%～107.3%,相对标准偏差小于8%,方法检测限可达0.010 mg/kg。本方法准确、灵敏、可靠,已应用于实际样品分析,并可作为鉴别地沟油的方法之一。     

近红外光谱分析技术在食用植物油分析检测中的应用

食用植物油的品质检测和掺伪鉴别对于保障其食用安全性以及消费者利益具有重要意义。传统的分析方法由于操作繁琐、耗时较长,因此不能满足大量样品的实时快速检测要求。近红外光谱分析技术由于可以实现快速、无损、在线和多组分同时检测,目前已快速发展成为一种应用于食品分析领域的新方法,具有较大的应用前景。本文主要综述了近年来近红外光谱技术在食用植物油领域的研究及应用进展,包括在食用植物油品种定性鉴别、掺伪检测、品质检测及其在煎炸等热加工过程中的理化指标检测等多个方面的研究,对近红外光谱技术在食用植物油检测中的检测原理、影响因素、准确度等进行了综合分析,同时对目前近红外光谱技术在食品领域应用存在的问题进行了分析总结,并对今后进一步研究提出了展望。     

植物油脂加工企业污水处理工艺分析及方案设计

根据现阶段植物油脂加工企业环保要求,分析了油脂加工生产线污水的特点和适宜的处理措施,并提出相应的工艺设计方案。     

植物油中微塑料污染潜在风险及控制

微塑料是指由塑料制品破碎而产生的直径小于5 mm且广泛分布于生态系统中的一种微型污染物。微塑料通常会随着植物汲取营养或动物进食被摄入体内,进而在生物体内不断富集,并产生多种危害。微塑料有良好的亲脂性,但植物油中微塑料的污染风险却未被重视。分析植物油在加工、运输和贮藏等过程中存在的微塑料污染的潜在风险及微塑料污染危害,进而对植物油中微塑料的检测与脱除方法进行论述,旨在为控制植物油微塑料污染提供一定参考。     

全二维气相色谱-质谱法检测动植物油

为建立动植物油的全二维气相色谱-质谱分析方法,选用四甲基氢氧化铵(25%)的无水甲醇(体积比1∶50)对样品进行甲酯化衍生,对二维色谱柱、程序升温、质量扫描范围、冷吹流量、调制周期进行优化。结果表明:在调制周期5 s,冷吹流量3 L/min,DB-5MS(30 m×0.25 mm×0.25μm)为一维柱,BP20(2.5 m×0.1 mm×0.1μm)为二维柱,质量扫描范围(m/z)71~385,程序升温为初始温度40℃,保持2 min,以30℃/min升温至190℃,再以2℃/min升温至280℃,保持15 min的条件下,动植物油中的脂肪酸组成得到了有效分离和准确检测,比气相色谱-质谱法灵敏度、分离效果均提高。为动植物油的进一步鉴别提供新的分析方法。     

植物油在婴儿配方乳粉中的应用探讨

从婴儿配方乳粉在用的7种植物油(大豆油、玉米油、核桃油、葵花籽油、高油酸葵花籽油、棕榈油和椰子油)入手,通过检测植物油的脂肪酸含量,对亚油酸、亚麻酸和油酸等几个主要指标进行了分析,进而与3种新型植物油(双低菜籽油、米糠油和红花籽油)的脂肪酸组成进行了比较,对新型植物油在婴儿配方乳粉中的应用进行了探讨。     

Effect of varying oxygen concentrations on the shelf-life of fresh pork sausages packaged in modified atmosphere

A total of 105 fresh pork sausages were packaged in atmospheres varying in oxygen concentration, using the following mixtures (%O₂/%CO₂/%N₂): 0/20/80, 0/20/80 + O₂ scavenger, 20/20/60, 40/20/40, 60/20/20, and 80/20/0. In addition, two batches were subjected to vacuum packaging or over-wrap with O₂-permeable film. They were stored for 20 days at 2 ± 1 °C in the dark. Values of pH, CIE L*, a* and b* color parameters, surface metmyoglobin percentage, TBA-reactive substances, psychrotroph aerobe bacterial numbers and sensory discoloration and off-odor were assessed throughout storage. Packaging in the absence of O₂, either under vacuum or in atmosphere with O₂ scavenger, led to extension of shelf-life in terms of both color and odor stability due to low oxidation rates. Increase of O₂ caused a significant enhancement of oxidation, decrease of shelf-life due to discoloration and off-odor development. The highest O₂ concentration gave rise to a significant color improvement, though only for a limited period of 8 days.