Melting Characteristics and Hardness of Milkfat Blend Sucrose Polyesters

Sucrose polyesters (SPE) are noncaloric fat substitutes prepared from fatty acid methyl esters (FAME) and sucrose. Our objectives were to determine and compare the effects of supplementing FAME from hydrolyzed milkfat with 25% FAME derived from beef tallow, coconut oil, or myristic acid on melting characteristics, hardness, and fatty acid profiles of SPE. DSC thermograms revealed different melting profiles among the SPE and anhydrous milkfat. Milkfat:tallow, milkfat:coconut, and milkfat SPE differed (p<0.05) in hardness from milkfat at 12.5, 22, and 27.5°C. Fatty acid compositions of the SPE were also different. Adjustments of melting characteristics, hardness, and fatty acid substituents of SPE are essential when substituting milkfat SPE for selected natural fats in foods.     

Milkfat Sucrose Polyesters as Fat Substitutes in Cheddar-type Cheeses

Milkfat sucrose polyesters (SPE) were substituted for 10, 25, 50, or 75% (w/w) of mllkfat in reconstituted milk and made into Cheddar-type cheeses. Total fat, moisture, and salt contents of the cheeses averaged 27, 49, and 1.2% (w/w). respectively. A screened sensory panel (n=22) determined that cheeses containing SPE were significantly different from the control cheese. Colorlmetrlc measurements of the total difference (ΔE) of the cheeses containing SPE from the control cheese increased as % SPE in the cheese increased (r=0.90). Firmness of the cheeses did not differ (p<0.05). Cheddar-type cheeses made with mllkfat SPE substituted for milkfat may have potential marketability.     

转化酶水解蔗糖加料烘焙对白肋烟品质的影响

为提高白肋烟的处理效果,进行了转化酶水解蔗糖和柠檬酸水解蔗糖的加料烘焙试验,并进行了加料烘焙前后烟叶还原糖、总糖、烟碱、钾、氯、氨基酸、中性和碱性香味成分分析及卷烟评吸。结果显示:①与加酸转化糖里料相比,采用加酶转化糖里料对烘焙后白肋烟中的常规化学成分影响基本相同,总氨基酸含量显著降低,碱性香味成分增多;②加酶转化糖里料的白肋烟的感官质量总体上比加酸转化糖的略有改善,其中香气质和香气量有较大改善,烟气浓度和凝聚性有一定程度的改善,白肋烟香和刺激性增强,杂气、干燥感、舒适程度等指标差异不大。酶转化糖可以替代酸转化糖进行白肋烟的加料。     

Acid-Hydrolyzed Starch Tailings Effects on Cookie Spread

A starch tailings fraction was isolated from wheat flour and hydrolyzed for various lengths of time with dilute sulfuric acid. Differential scanning calorimetry showed that the hydrolyzed starch tailings were almost as effective as sugars in raising the onset temperature for gelatinization of starch. A sample hydrolyzed 2 hr increased the onset temperature by the same extent as an equal weight of sucrose. When sucrose in cookies was completely replaced by hydrolyzed starch tailing fractions, the spread of the cookies depended on the molecular size of the polysaccharides in the fraction added. Cookies containing a sample hydrolyzed for 0.5 hr had the least spread, whereas those containing starch tailings hydrolyzed for 2 hr spread the most.     

相转移催化合成大豆油蔗糖多酯初步研究

以大豆油和蔗糖为原料,十六烷基三甲基溴化铵为相转移催化剂,采用两步法合成大豆油蔗糖多酯。初步筛选了合适的助熔剂(脂肪酸皂),并确定了最佳工艺条件:蔗糖粒度120目,搅拌速率500 r/min,催化剂用量3%,反应温度130℃,n(乙酯)∶n(蔗糖)为12∶1,反应时间6 h。在最佳工艺条件下反应得到蔗糖多酯产率达到89.12%,酯化度6.8。对蔗糖多酯和大豆油的理化特性进行了比较,两者性质接近。最后借助薄层色谱(TLC)、红外光谱(IR)对产品结构做了初步鉴定,产品达到预期目标,可以作为普通食用油替代品。     

特级初榨橄榄油中酚类化合物不同提取方法对比研究

采用液液萃取法(LLE)、固相萃取法(SPE)和液液微萃取法(LLME)分别对特级初榨橄榄油中酚类成分进行提取,应用超高效液相色谱-高分辨质谱法(UPLC-HRMS)及Folin-Ciocalteus比色法分别进行酚类化合物组成研究和总酚含量测定,比较3种方法的提取效率。结果表明:特级初榨橄榄油中共检测到40种酚类化合物,其中液液萃取样品检出33种,固相萃取样品检出20种,液液微萃取样品检出15种,液液萃取法提取酚类化合物种类显著多于其他两种方法;液液萃取法提取的总酚含量分别为固相萃取法及液液微萃取法的2. 9倍和3. 7倍,液液萃取法对酚类化合物的提取效率明显优于其他两种方法;但从实验过程角度考量,液液微萃取法具有操作简单、省时省力、有机溶剂用量少、对实验人员伤害小、环境污染小等优点,具有进一步优化的潜力。     

Zur Synthese und Charakterisierung von Saccharosefettsäurepolyestern 1. Mitt, Über ein neues Syntheseverfahren

On the synthesis and characterization of sucrose fatty acid polyesters. Part I. On a new synthesis process A new process is described for the synthesis of sucrose fatty acid polyesters (SPE) as transesterification of sucrose acetate with fatty acid methyl esters in the absence of solvents and in the presence of alkali metal catalysts. SPE are formed with yields of 80 to 90% at the following conditions: molar ratio of fatty acid methyl ester to sucrose acetate at least 8:1, reaction temperature between 110 and 120 °C, reaction time 3 h, and catalyst concentration of 2% sodium or potassium.     

Optimized Synthesis of Sucrose Polyesters: Comparison of Physical Properties of Sucrose Polyesters, Raffinose Polyesters and Salad Oils

Synthesis and purification of sucrose polyesters (SPE) were optimized to obtain high yields of SPE. Sucrose octaacetate (SOAC) and fatty acid methyl esters (FAME) of salad oils or FAME blends of homogenous fatty acids and salad oils were interesterified in the presence of sodium metal. Yields 99.6–99.8% of purified SPE based on initial weight of SOAC were obtained. SPE structure was confirmed by infrared (IR) and C-13 nuclear magnetic resonance (C-13 NMR) spectroscopy. Physical properties of SPE and raffinose polyesters (RPE) were similar to physical properties of conventional salad oils. The hydrophile-lipophile balance (HLB) of SPE and RPE were between 2–6 HLB units. Differential scanning calorimetry (DSC) was used to determine the melting properties of SPE and RPE. Neither SPE nor RPE was susceptible to in vitro lipolysis.     

蔗糖转化果葡糖浆的生产工艺和分离提取研究进展

简述了蔗糖水解生产果葡糖浆的相关工艺技术,包括酸催化水解法、酶水解法和阳离子交换树脂法,同时介绍了果葡糖浆的分离技术,包括离子交换树脂吸附分离、色谱分离、结晶分离、硼酸盐分离、复盐分离等,以期为蔗糖转化果葡糖浆的资源化高效利用提供参考。     

不同种类的酸对蔗糖的水解催化研究

利用高效液相色谱-蒸发光散射检测法分析测定了盐酸、柠檬酸和酒石酸对蔗糖水解过程中蔗糖、葡萄糖和果糖转化量的变化,并结合酸催化蔗糖水解反应机理对蔗糖水解过程进行研究。结果表明：在pH 2、反应温度90℃时,蔗糖在1 h内能够完全水解,并且不会产生过多的副反应。     

HPLC测定亚麻籽油苦味肽的纯化富集前处理研究

比较了高效液相色谱(HPLC)定量测定亚麻籽油苦味肽(CLE)的溶剂萃取法和固相萃取法(SPE)纯化富集前处理效果,并对不同规格SPE硅胶小柱填料的前处理效果作了对比。结果表明,通过溶剂萃取法和固相萃取法前处理的亚麻籽油样品,进行HPLC定量测定时,CLE均可以在液相色谱中得到良好的分离,前处理方法并不影响CLE的出峰时间及峰形。但与溶剂萃取法相比,SPE所提取的环肽样品中甘油三酯及其他杂质显著减少,这有利于保护液相色谱柱、提高柱效。随着SPE硅胶小柱填料量的增加,CLE测定值减小,使用填料规格为0. 5 g的SPE硅胶小柱可以得到较好的分离及富集效果。SPE硅胶小柱预处理所得物经超高效液相色谱-质谱联用分析证实为CLE。SPE可有效提取富集亚麻籽油所含的CLE,适用于HPLC定量检测CLE的前处理,该方法样品加标回收率为92. 62%,组内精密度相对标准偏差为0. 62%,组间精密度相对标准偏差为1. 79%。     

Characterization of aroma potential of apricot varieties using different extraction techniques

Aroma compounds are presents in raw foods, freely and glycosidically-bounded (aroma precursors). In the present work, the volatile fraction of eight varieties of apricot were analyzed using simultaneous distillation extraction (SDE), solid phase extraction (SPE) with reverse phase (C18), liquid–liquid extraction (LLE) and headspace-solid phase microextraction (HS-SPME). The free aroma compounds were identified by GC–MS, finding common compounds such as linalool, α-terpineol, β-ionone and γ-decalactone and specific compounds due to the extraction method used. The ANOVA showed a significant effect in the extraction techniques and on the varieties in the free aromatic fraction from apricot as well. In spite of a large number of volatile compounds extracted by SPE, the technique that allowed for the most number of compounds to be extracted was SPME.     

柚皮提取物的抑菌作用

用乙醇作提取剂提取柚皮 ,将提取物经过初步分离纯化得到黄酮含量为 1 0 9%的柚皮提取物 (SPE) ,并对其抑制细菌和霉菌的作用进行了研究。用滤纸片扩散法测定了相对抑菌活性 ,采用固体稀释法确定柚皮提取物的最小抑菌浓度 (MIC) ,并进一步研究了 pH值、温度对柚皮提取物抑菌作用的影响 ,采用 3点接种法初步研究了样品对米曲霉、黑曲霉、青霉的抑制作用。结果表明 ,柚皮提取物对大肠杆菌和金黄色葡萄球菌的抑制作用较强 ,其MIC均为 2 5 %;对沙门氏菌的抑制作用较弱 ,其MIC >2 5 %;pH值和温度对柚皮提取物的抑菌活性均有影响 ,SPE在偏酸性条件下抑菌效果较好 ;样品经 5 0℃处理对其抑菌活性影响不大 ;但处理温度提高到 80℃和 1 0 0℃时 ,其抑菌活力明显降低。在供试的 3种霉菌中 ,柚皮提取物对黑曲霉的抑制作用最强 ,抑制率为60 5 %;对米曲霉的作用较差 ,抑制率为 34 3%。     

Development of Hydrolyzed and Hydrolyzed-lsomerized Syrups from Cheese Whey Ultrafiltration Permeate and Their Utilization in Ice Cream

Hydrolyzed lactose syrup (HLS) was produced from cheese whey ultrafiltration permeate by treatment with immobilized β-galactosidase, deionization, and evaporation. The degree of hydrolysis was 97.2%. Hydrolyzed-isomerized lactose syrup (HILS) was produced from hydrolyzed, deionized ultrafiltration permeate by treatment with immobilized glucose isomerase, deionization and evaporation. The degree of isomerization was 34.8%. HLS and HILS were substituted for 25% or 50% of the sucrose (on a solids basis) in vanilla ice cream. The mix freezing time increased when HLS or HILS was substituted for sucrose at a level of 50%. There were no significant differences in melting rates (P < 0.05) and few differences in sensory quality.     

罐头食品中双酚A和双酚F环氧衍生物残留的高效液相色谱分析

建立了一种高效液相色谱分析罐头食品中双酚A(BPA)和双酚F(BPF)环氧衍生物的方法。样品经微波辅助萃取后过PPL(填料为苯乙烯-二乙烯苯(SDVB)聚合物)固相萃取柱进行净化试验。结果表明,微波辅助萃取法的提取效果理想;采用PPL固相萃取回收率在73.26%~104.98%,除杂效果明显。将微波辅助—PPL固相萃取净化法应用于多种食品进行分析,结果表明该方法适用于食品中双酚A和双酚F环氧衍生物残留分析。     

Toxicological evaluation of saccharose carbonic acid esters in basic subchronic feeding trials with rats. 1. Effect of saccharose fatty acid polyester

Groups of male and female rats received a sucrose fatty acid polyesters containing product (SPE) in their diet for 13 weeks at levels of 0, 5, 10 or 15%. Additional groups were pair-fed to the high-dose SPE-group (standard diet, 92.5%) or given food containing 7.5% hydrogenated lard (HF) or 4.5% fatty acid ethyl ester (FEE). Compared to the controls, there were increases in the food intake in males and females of the SPE-groups, HF- group and FEE-group. Male rats fed SPE showed increases in serum urea nitrogen at all levels, in serum alkaline phosphatase activity and urinary glucose excretion at 10 and 15%, in serum leucine amino-peptidase at 15%. In females dietary SPE increased the blood glucose content and serum alkaline phosphatase activity at 15% and the serum leucine aminopeptidase activity at 10 and 15%.     

Determination of Underivatized Glyphosate Residues in Plant-Derived Food with Low Matrix Effect by Solid Phase Extraction-Liquid Chromatography-Tandem Mass Spectrometry

A method was developed for the determination of glyphosate residues in plant-derived food using a two-step solid phase extraction (SPE) combined with mixed-mode liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted with water. Then, the extracting solution was pretreated by a C18 cartridge to remove protein and weak-polar interferences and further directly extracted using a strong anion exchange (SAX) cartridge to remove neutral and basic substances. The obtained glyphosate residues from the SPE were separated on a hydrophilic interaction/weak anion-exchange (HILIC/WAX) column and detected by mass spectrometry with negative electrospray ionization (ESI-) in multiple reaction monitoring (MRM) mode. This approach was evaluated by five different kinds of plant-derived food (soybean, corn, carrot, apple, and spicy cabbage) matrices in terms of matrix effect and recovery. Results showed that two-step SPE and mixed-mode chromatography separation provided the method with a very low matrix effect, and the spiked recoveries of glyphosate were satisfied in the range of 83.1 to 100.8 % at three spiked levels. The limit of quantification (LOQ) and detection (LOD) of the method in different matrices were 0.016–0.026 and 0.005–0.008 mg kg^?1, respectively. The procedure was validated and showed good accuracy and precision over a large linear range of 0.02–10 mg kg^?1.     

酶解花生蛋白在面条加工中的应用

以脱脂花生蛋白粉为原料,用乙醇溶液浸制备花生浓缩蛋白,制得的花生浓缩蛋白再经菠萝蛋白酶解,得到的浓缩酶解蛋白与小麦粉混合,并添加一定比例的谷氨酰胺转移酶,通过正交试验及感官评定确定最佳的工艺条件。结果表明：浓缩酶解花生蛋白添加比例为8%时,谷氨酰胺转移酶量为900U/kg时,面条质感最好。添加酶解后花生浓缩蛋白能有效改善面条品质,提高其营养价值。     

Optimization of ethanol extraction and further purification of isoflavones from soybean sprout cotyledon

Isoflavones from cotyledons of soybean sprouts were extracted with aqueous ethanol and further concentrated to obtain a product with a high concentration of isoflavone. The ethanol concentration, extraction time and reaction temperature were optimized by using response surface methodology (RSM). Isoflavones in aqueous ethanol were concentrated by a three-step procedure comprised of solid phase extraction (SPE) with Diaion HP-20 and Amberlite-XAD-2 adsorption columns, acid hydrolysis, and liquid–liquid extraction. The maximum amount of isoflavone in aqueous ethanol extracts (11.6 mg/g solid) was obtained when isoflavones in cotyledons (2.18 mg/ g solid) were extracted with 80–90% (v/v) aqueous ethanol above 90 °C for more than 100 min. The isoflavone extracts, obtained by SPE with a Diaion HP-20 column contained 100 mg/g solid. The liquid–liquid extraction (LLE) with ethyl ether further concentrated the extracts up to 229 mg/g solid, retaining 63% of the initial isoflavones.     

Plasticizer Effect on Grease Barrier and Color Properties of Whey-protein Coatings on Paperboard

Whey protein concentrates with ?80% protein (WPC‐80) plasticized with 0.64 M glycerol or sucrose, or with 0.34 or 0.64 M sorbitol or polyethylene glycol (PEG) 200, produced flexible films. WPC‐80 with hydrolyzed lactose required addition of less sucrose to produce flexible films. WPC‐80 films formed as coatings on paperboard gave a grease barrier comparable to WPI film‐coatings. Long‐term ambient storage of WPC‐80 coated paperboard indicated that the use of sucrose as plasticizer imparted good grease resistance and minimized plasticizer migration.