Flour,starch and alternative (wheatless) breadmaking quality of various cassava clones

Alternative (wheatless) cassava breads were made with cassava flour from eight different cassava (Manihot esculenta, Crantz) clones fortified with soya flour (200 g kg^?1 total flour) using margarine and egg white, or xanthan, as additives. In this study, bread specific volumes were reliably predicted from only the diastatic activity and maximum paste viscosity of the cassava flour, although further variables still need to be investigated. Flours with diastatic activities above ～ 145 mg of maltose, and indirectly low maximum paste viscosities, produced dense, pudding-like structures with completely gelatinised crumbs. The flour diastatic activity was dependent on the moisture content of the freshly harvested tuberous root; above a critical threshold moisture (～ 75 %) content the specific air intake of the loaves decreased sharply. The extent of starch gelatinisation and solubilisation did not critically affect loaf volumes but affected crumb structures.     

Determination of nickel in Polish brands of margarines

Nickel is used in the production of margarine as a catalyst for hydrogenation. This may lead to the presence of its residues in the products and could cause allergic reactions. Therefore, monitoring of this metal in foods is essential for consumers. The described liquid sampling AAS procedure allows product control. Nickel was determined in 10 brands of margarine, and only in 3 samples its content was below the acceptable limit of 0.2?mg?kg^?1.     

The Production of an Experimental Table Margarine Enriched with Conjugated Linoleic Acid (CLA): Physical Properties

Even though conjugated linoleic acid (CLA) is known to have some beneficial effects on the human body, its consumption has decreased over the past 20 years due to the replacement of animal fats by vegetable oils. In this study, using the structured lipid (SL) containing CLA, an experimental table margarine enriched with CLA was produced and stored for 3 months at two temperatures prior to performing the relevant analyses. The GC results showed that the margarine fat had 10.6% CLA. The solid fat content was the highest in week 0 in all samples, which then decreased during storage but the hardness increased. An increment in dropping point was also observed in the samples. In week 0, all the samples had the β′ crystal as the predominant crystal form but a crystal transformation from β′ to β was observed during storage.     

凝胶油基人造奶油质地和流变性能

凝胶油作为潜在的能够替代传统氢化奶油的新方法,具有低饱和脂肪酸和零反式脂肪酸的优势,所受关注 度越来越高。本实验以精炼大豆油为基料油,β-谷甾醇和卵磷脂等比例混合物作为复合凝胶剂,制备得到凝胶油基 人造奶油。主要研究了凝胶剂质量分数和水分体积分数对凝胶油基人造奶油质地、流变学性能、微观网络结构和结 晶度的影响。结果表明：当水分体积分数提高时,能够在更低的凝胶剂质量分数下形成均相人造奶油体系;随着凝 胶剂质量分数和水分体积分数的增加,人造奶油的硬度和弹性增大;样品网络结构和结晶度的分析结果表明,随着 凝胶剂质量分数和水分体积分数的增加,人造奶油的结晶度增加,微观三维网络结构更加完整,油-水两相接触面 积变大,最终使得人造奶油体系结构更加均匀和稳定,硬度和弹性也更大。     

用管式急冷加工机生产片状酥皮玛琪琳

酥皮玛琪琳要具备塑性和稳固性。用急冷管式冷冻加工机可以灵活改变工艺流程。油脂深加工过程中,冷冻对结晶有决定性的影响。不同配方的产品要有不同的生产工艺和熟成条件。     

Chemical and Enzymatic Interesterification of a Blend of Palm Stearin: Soybean Oil for Low trans-Margarine Formulation

A blend of palm stearin and soybean oil (70/30, wt%) was modified by chemical interesterification (CIE) and enzymatic interesterification (EIE), the latter batch-wise (B-EIE) and in continuous (C-EIE). Better oil quality, mainly in terms of acidity, free tocopherol and partial acylglycerol content, was obtained after EIE. The clear melting point after any interesterification process was similar and about 9 °C lower as result of the modification in the TAG profile, which approaches the calculated random distribution. Interesterification changed the SFC profile significantly. For the fully refined interesterified blends, the SFC profile was similar and clearly different from the starting blend. Interesterification decreased the content of solids at temperatures >15 °C and increased the content of solids at temperatures <15 °C. This increase was less remarkable after C-EIE, suggesting that full randomization was not achieved in the used conditions, probably caused by a too short residence time of the oil in the enzymatic bed. During B-EIE, variations in SFC with time, principally at low temperatures, were still observed although the TAG composition was stable. At low temperatures, the reaction rate calculated from SFC was very low, confirming an important effect of the acyl migration on this parameter.     

Trans fatty acid determination in fats and margarine by fourier transform infrared spectroscopy using a disposable infrared card

The use of a disposable polyethylene infrared (IR) card as a sample carrier for the quantitative determination of trans content of fats and oils and margarine by Fourier transform IR spectroscopy was investigated. Standards prepared by dissolving trielaidin in a zero-trans oil were used to develop partial least squares (PLS) calibrations for both the IR card and a 100-μm transmission flow cell. These calibrations were then used to predict a series of gas chromatographically-preanalyzed unknowns, the trans predictions obtained using the card being comparable to those obtained with the transmission flow cell. Somewhat improved performance could be obtained when the spectral data from the card were normalized to compensate for inherent variations in path length and variability in sample loading. Both IR methods tracked the gas chromatographic reference trans values very well. A series of margarine samples was also analyzed by the card method, producing results similar to those obtained using a flow cell. For the analysis of margarines, the card method has the advantage that the trans analysis can be performed directly on microwave melted emulsions because moisture is not retained on the card. Overall, the disposable IR card was shown to work well and has the benefit of allowing trans analyses to be carried out without requiring investment in a heated flow cell or attenuated total reflectance accessory.     

Effect of blending and emulsification on thermal behavior, solid fat content, and microstructure properties of palm oil-based margarine fats

The ability of palm oil (PO) to crystallize as beta prime polymorph has made it an attractive option for the production of margarine fat (MF). Palm stearin (PS) expresses similar crystallization behavior and is considered one of the best substitutes of hydrogenated oils due to its capability to impart the required level of plasticity and body to the finished product. Normally, PS is blended with PO to reduce the melting point at body temperature (37 °C). Lipid phase, formulated by PO and PS in different ratios were subjected to an emulsification process and the following analyses were done: triacylglycerols, solid fat content (SFC), and thermal behavior. In addition, the microstructure properties, including size and number of crystals, were determined for experimental MFs (EMFs) and commercial MFs (CMFs). Results showed that blending and emulsification at PS levels over 40 wt% significantly changed the physicochemical and microstructure properties of EMF as compared to CMF, resulting in a desirable dipalmitoyl-oleoyl-glycerol content of less than 36.1%. SFC at 37 °C, crystal size, crystal number, crystallization, and melting enthalpies (ΔH) were 15%, 5.37 μm, 1425 crystal/μm(2), 17.25 J/g, and 57.69J/g, respectively. All data reported indicate that the formation of granular crystals in MFs was dominated by high-melting triacylglycerol namely dipalmitoyl-oleoyl-glycerol, while the small dose of monoacylglycerol that is used as emulsifier slowed crystallization rate. Practical Application: Most of the past studies were focused on thermal behavior of edible oils and some blends of oils and fats. The crystallization of oils and fats are well documented but there is scarce information concerning some mechanism related to crystallization and emulsification. Therefore, this study will help to gather information on the behavior of emulsifier on crystallization regime; also the dominating TAG responsible for primary granular crystal formations, as well as to determine the best level of stearin to impart the required microstructure properties and body to the finished products.     

Comparison of two methods for the direct determination of fat in butter,blended spreads,and margarine

A German (GE) method and a New Zealand (NZ) method for the direct determination of total fat in spreadable fats were compared in a pilot collaborative study to obtain preliminary information regarding the precision and the level of fat content determined. The study comprised six products, including butter, blended fat products, and margarine with a fat content in the range of 39—82%, and four laboratories. The GE method, based on a Soxhlet extraction using petroleum ether, yielded a repeatability estimate of 0.41 g/100 g and a reproducibility estimate of 0.79 g/100 g. The NZ method, based on an extraction of the fat by thorough shaking of the sample with petroleum ether followed by phase separation, yielded a repeatability estimate of 0.32 g/100 g and a reproducibility estimate of 0.62 g/100 g. The difference in precision estimates between the two methods was significant for repeatability, but not for reproducibility. The better repeatability of the NZ method was probably partly due to the use of a superior sample preparation procedure which ensured that any inhomogeneity developed inside the sample container during transport or storage was removed. The average fat content as determined by the NZ method was 0.20 g/100 g higher than that determined by the GE method, but for individual samples no constant bias was observed. However, an inverse correlation between the bias and the fat content of the product suggested that the anhydrous sodium sulphate used in the GE method interfered with the fat recovery when analysing samples containing a high percentage of water. Thus, according to this study, the NZ method seems to have certain advantages over the GE method with respect to the results obtained.