脱酸米糠毛油品质对吸附脱色综合效果的影响

采用碱炼脱酸和水蒸汽蒸馏脱酸两种不同脱酸工艺所得米糠油进行吸附脱色试验,以米糠油脱色率及谷维素、甾醇、维生素E等营养成分保留率和反式脂肪酸生成量作为考察指标,分析研究待脱色米糠油品质对吸附脱色综合效果的。结果显示,在脱色率、VE保留率和反式酸含量方面碱炼脱酸米糠油的综合脱色效果优于水蒸汽蒸馏脱酸米糠油。碱炼脱酸米糠油的最佳吸附脱色条件为:凹凸棒石为吸附剂,用影响量为油重的4%,脱色时间30 min,脱色温度110℃。在最佳工艺条件下,测得米糠油脱色率为75.08%,脱色米糠油的色泽为Y35、R2.1(罗维朋比色槽25.4 mm),满足国标三级米糠油色泽要求;谷维素保留率为88.89%(脱色前后谷维素含量分别为0.90%、0.80%、),甾醇保留率为73.87%(脱色前后甾醇含量分别为2.32%、1.71%),维生素E保留率为82.90%(脱色前后维生素E含量分别为50.57 mg/100 g、41.92 mg/100 g);与水蒸汽蒸馏脱酸米糠油相比,相同脱色条件下,脱色率提高7.84%,维生素E保留率提高7.64%,但谷维素保留率下降4.74%,甾醇保留率下降4.58%。脱色前后碱炼脱酸米糠油中未检出反式酸,水蒸汽蒸馏脱酸米糠油中反式酸含量为0.40%,脱色后反式酸含量增加了0.02%。虽然谷维素和甾醇的保留率相对降低,但两者的保留率仍达到了88.89%、73.87%,脱色油中两者含量分别为0.80%、1.71%,单就脱色过程而言,营养成分保留率还是很高的。     

高酸值米糠油的活性白土与硅胶联合脱色工艺研究北大核心CSCD

对高酸值米糠油的活性白土与硅胶联合脱色工艺进行研究。对酸值(KOH)为27 mg/g的米糠油进行先活性白土后硅胶脱色,以脱色率、谷维素含量和精炼率为考察指标,在单因素试验的基础上采用响应面试验优化活性白土与硅胶联合脱色条件。结果表明:活性白土脱色最优工艺条件为活性白土添加量2.5%、脱色时间30 min、脱色温度90℃;硅胶脱色最优工艺条件为硅胶添加量2.0%、脱色时间30 min、脱色温度82℃。在最优工艺条件下,活性白土脱色后,米糠油脱色率为79.15%,谷维素含量为2.14%,精炼率为90.05%;再经硅胶脱色后,米糠油脱色率为47%,谷维素含量为2.10%,精炼率为88.36%。经过活性白土与硅胶联合脱色后米糠油的色泽明显改善,色泽(25.4 mm罗维朋比色槽)由原油的Y35、R15降至Y5、R0.3。     

米糠油萃取脱酸结合吸附脱酸工艺效果研究北大核心CSCD

为了在脱酸的同时尽可能保留米糠油中的营养成分,采用乙醇萃取脱酸结合碱性微晶纤维素吸附脱酸的低温物理脱酸技术对米糠油进行脱酸。以乙醇萃取脱酸米糠油为原料,以脱酸率为考察指标,采用单因素实验和正交实验对米糠油的吸附脱酸工艺条件进行了优化,同时对比了碱炼脱酸与乙醇萃取脱酸结合吸附脱酸对米糠油品质的影响。结果表明:最佳吸附脱酸工艺条件为碱性微晶纤维素添加量3.0%、吸附时间2.0 h、吸附温度40℃,在此条件下米糠原油经乙醇萃取脱酸结合吸附脱酸处理后,酸值(KOH)由35.04 mg/g降到0.92 mg/g,谷维素的保留率为73.0%,总甾醇保留率为74.3%,总生育酚保留率为56.5%;而米糠原油经碱炼脱酸处理后,酸值(KOH)由35.04 mg/g降到1.16 mg/g,谷维素的保留率为60.1%,总甾醇保留率为65.6%,总生育酚保留率为44.6%。可见,与传统碱炼脱酸相比,萃取脱酸结合吸附脱酸的方法对米糠油中谷维素、甾醇、生育酚的保留率更高,对游离脂肪酸的脱除效果更好。     

低反式脂肪酸含量大豆油脱色条件的优化

对大豆油脱色过程中反式脂肪酸含量进行研究,通过单因素试验与响应面分析,对影响脱色的主要工艺参数进行了优化.得到低反式脂肪酸大豆油脱色的最佳工艺参数为:脱色温度97℃,脱色时间30 min,脱色剂用量3.8%.在真空度0.095 MPa、搅拌速度220 r/min条件下,按最佳工艺参数脱色,得到大豆油反式亚油酸含量为1.18%,脱色率达到96.57%.     

脱臭过程中保留米糠油中植物甾醇的工艺优化

采用氮气蒸馏法进行米糠油的脱臭,研究了脱臭温度、脱臭时间以及氮气流速对脱臭米糠油中植物甾醇含量的影响。结果表明,在保证得到高品质米糠油的前提下,最大程度保留脱臭油中植物甾醇的优化工艺条件为:脱臭温度260℃,脱臭时间120 min,氮气流速0.12 m3/h。在最优工艺条件下,植物甾醇保留率(相对于脱色油)为83.38%,米糠油酸值(KOH)为0.25 mg/g,精炼率为93.01%。同时发现,脱臭前后米糠油中植物甾醇的主要组成成分没有变化,均为豆甾醇、菜油甾醇和β-谷甾醇。     

玉米胚预榨毛油和浸出毛油品质及综合脱色效果的研究

研究了玉米胚预榨浸出生产中所得预榨毛油和浸出毛油的品质及其脱色效果和脱色过程中营养成分的保留率。结果显示,预榨毛油比浸出毛油的色泽浅、维生素E含量高、酸价也较低;添加相同量的活性白土分别对两种毛油进行吸附脱色,预榨毛油较浸出毛油脱色率平均高出约4.6%;白土用量4%时,脱色预榨毛油的色泽基本达到玉米油国标中二级油的指标,而浸出毛油即使在白土用量6%时其色泽也很难达到二级油指标;经吸附脱色,预榨毛油中植物甾醇和维生素E保留率普遍高于浸出毛油,在白土用量5%时,预榨毛油较浸出毛油甾醇保留率高出14%,不同白土用量,预榨毛油比浸出毛油甾醇保留率平均高出约10%;白土用量2%时,预榨毛油较浸出毛油维生素E保留率提高约5.6%;两种玉米毛油所含维生素E中4种生育酚及4种生育三烯酚都存在,组分齐全;吸附脱色过程中γ-生育酚和β-、γ-生育三烯酚的损失较明显,其他组分含量的损失较少。因此,合理的玉米油精炼应将预榨毛油和浸出毛油分别进行适度精炼,以提高吸附脱色效果和营养成分保留率。     

脱臭工艺条件对葵花籽油综合品质影响的研究

分析对比了在220~270℃、100 min及40~120 min、260℃脱臭条件下,葵花籽油中邻苯二甲酸酯类塑化剂(PAEs)、多环芳烃(PAHs)、维生素E(V_E)、甾醇、脂肪酸组成及酸值、过氧化值、烟点、色泽的变化,考察脱臭工艺条件对葵花籽油综合品质的影响。结果表明:随着脱臭温度升高、脱臭时间延长,葵花籽油中PAEs、PAHs各组分脱除率均逐渐升高;V_E、甾醇含量逐渐降低,保留率分别由94.6%降至63.2%及94.4%降至81.6%;反式脂肪酸含量逐渐升高,由0.17%升至1.16%。综合不同脱臭条件对PAEs、PAHs、V_E、甾醇、反式脂肪酸及其他质量指标的影响,基于塑化剂和多环芳烃深度脱除的脱臭条件为260℃、80~100 min,此条件下V_E保留率为73%~75%,甾醇保留率82%~85%,反式脂肪酸含量0.88%~0.90%;保证BaP达标的适度脱臭条件为260℃、60 min或220℃、100 min。260℃、60 min条件下,V_E和甾醇保留率分别为79.3%和85.4%,反式脂肪酸含量0.69%;220℃、100 min条件下,V_E和甾醇保留率均在94%以上,反式脂肪酸含量0.17%。可根据待脱臭油风险成分的含量不同以及对脱臭成品油的限量要求不同选择相应的优化脱臭条件,采用精准的脱臭技术提升葵花籽油综合品质。     

以稻米油为基油制备稻米调和油及其煎炸性能的研究

对稻米油、稻米调和油、添加0.02%迷迭香提取物的稻米调和油和添加0.06%茶多酚的稻米调和油4种煎炸油进行土豆条连续煎炸试验,对比4种煎炸油在煎炸过程中的极性组分、脂肪酸组成、维生素E、甾醇、谷维素、反式脂肪酸(TFA)、3-氯丙醇酯(3-MCPD酯)和苯并芘含量变化,综合评估其煎炸性能。结果表明:稻米油、稻米调和油、添加迷迭香提取物的稻米调和油和添加茶多酚的稻米调和油的极性组分含量分别在煎炸10、14、16 h和14 h超过国家标准;稻米调和油的谷维素保留率均优于稻米油;添加迷迭香提取物有利于维生素E和谷维素的保留;添加茶多酚有利于甾醇的保留;反式脂肪酸和苯并芘的含量均未超过国家标准限值。     

高谷维素米糠油精炼工艺研究

为优化高谷维素米糠油精炼工艺,以谷维素保留率、磷脂含量、色泽、米糠油得率等为考察指标,对米糠毛油进行磷酸水化脱胶、脱蜡、脱色、脱臭、物理-化学联合脱酸等精炼处理。研究结果表明,加水量6%时,磷酸水化脱胶效果最好,谷维素保留率为96.5%;温度120℃、时间20 min时,活性白土和活性炭的脱色效果最好,谷维素保留率为90.2%;先通过物理精炼将酸价降低8 mg KOH/g,再采用化学精炼,米糠油得率达到最高值87.2%,谷维素保留率为87.6%。     

酶法酯化脱酸米糠油产品质量与安全性评价

对酶法酯化脱酸工艺所生产的米糠油进行了质量与安全性评价。分别对其特征指标、品质指标、食品安全指标、甘油三酯组成、油脂伴随物含量,以及炼耗、辅料消耗、能耗等工艺指标进行了分析,发现酶法酯化脱酸米糠油的特征指标和质量指标均符合我国米糠油国家标准的要求,其脂肪酸、甘油三酯组成与传统工艺所生产米糠油无明显差异,维生素E、甾醇、角鲨烯、谷维素等有益伴随物保留率更高,反式脂肪酸、3-氯丙醇酯、缩水甘油酯等风险因子生成量减少,且得率大幅度提高,辅料消耗、能耗等显著降低。酶法酯化脱酸工艺所生产的米糠油是一款更安全、更营养的米糠油产品。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.