Development of a quantitative GC-FID method for the determination of sucrose mono- and diesters in foods

Sucrose esters (E 473) are emulsifiers used in foods to improve different technological properties. They should conform to the specifications laid down in Commission Regulation No. 231/2012 and be used at amounts not exceeding the maximal ones set by Commission Regulation No. 1129/2011. In order to be able to characterise commercial sucrose ester formulations and to evaluate whether they are used correctly by the food industry, a quantitative GC-FID method was developed. Standards of monoesters and diesters were isolated from commercial additive preparations because no commercial ones were available. Commercial sucrose monolaureate and in-house-synthesised sucrose diarachidonate were used as internal standards. The method showed limits of detection and quantification of 2.9 and 5.7 µg ml^–1 respectively for the monoesters and 42.8 and 129.7 µg ml^–1 respectively for the diesters. The analysed commercial additive formulations contained mainly mono- and diesters of palmitic and stearic acid with low amounts of free fatty acid and sucrose. Different food matrices were incurred with commercial sucrose esters formulations and recoveries ranged between 92% and 118% for the monoesters and between 77% and 120% for the diesters. Recovery of sucrose monoesters in cake was around 34% when no enzymatic treatment was applied, and about 64% when enzymatic treatment with Clara-Diastase was applied. This indicated that sucrose esters can interact strongly with the matrix during food production and that treatment with enzymes is essential to determine the esters’ content accurately in some classes of food products.     

Emulsifiers: Effects on Quality of Fibre-Enriched Wheat Bread

Resistant starch (RS) is a nutritional ingredient commonly used in bread products as dietary fibre (DF). This ingredient presents similar physiological functions than those imparted by DF, promoting beneficial effects such as the reduction of cholesterol and/or glucose levels on blood. Quality improvement of bread containing RS, with an optimized combination of emulsifiers, will be useful in the development of new and healthy bakery products. The objective of this research was to analyse the effects of different emulsifiers on several quality parameters of dough and bread prepared with wheat flour partially substituted with resistant starch as a dietary fibre. A blend of wheat flour/maize-resistant starch (MRS; 87.5:12.5) with sodium chloride, ascorbic acid, α-amylase, compressed yeast and water was utilized. Emulsifiers were incorporated to formulations in different levels according to a simplex centroid design. The viscoelastic, textural and extensional properties of dough were analysed. Bread quality was evaluated throughout the gelatinization and retrogradation of starch, specific volume of loaves, and texture and firmness of bread crumb. The incorporation of 12.5% (w/w) of MRS to wheat flour caused an increase of 5% in water absorption. Stability decreases markedly (from 9.9 to 2.2 min) and the mixing tolerance index increased (from 79 to 35 UF). The sodium stearoyl lactylate (SSL)–diacetyl tartaric acid esters of monoglycerides (DATEM) mixture increased hardness and resistance to extension on dough, whilst dough containing Polysorbate 80 (PS80) was softer; nevertheless, both types of dough retained less CO₂. An optimized concentration of the three emulsifiers (0.24% SSL, 0.18% PS80, 0.08% DATEM, w/w) was obtained by surface response methodology. The bread prepared with this combination of emulsifiers presented a considerable specific volume with a very soft crumb.     

Enzymatic Synthesis of Refined Olive Oil‐Based Structured Lipid Containing Omega ‐3 and ‐6 Fatty Acids for Potential Application in Infant Formula

Structured lipids (SLs) containing palmitic, docosahexaenoic (DHA), and gamma‐linolenic (GLA) acids were produced using refined olive oil, tripalmitin, and ethyl esters of DHA single cell oil and GLA ethyl esters. Immobilized Lipozyme TL IM lipase was used as the biocatalyst. The SLs were characterized for fatty acid profile, triacylglycerol (TAG) molecular species, solid fat content, oxidative stability index, and melting and crystallization profiles and compared to physical blend of substrates, extracted fat from commercial infant formula (IFF), and milk fat. 49.28 mol% of palmitic acid was found at the sn‐2 position of SL TAG and total DHA and GLA composition were 0.73 and 5.00 mol%, respectively. The total oleic acid content was 36.13 mol% which was very close to the 30.49% present in commercial IFF. Comparable solid fat content profiles were also found between SLs and IFF. The SLs produced have potential for use in infant formulas.     

Estimation of sucrose esters (E473) in foods using gas chromatography-mass spectrometry.

A method was developed for estimating the content in foods of the emulsifying additive E473, sucrose esters of fatty acids. The analytical approach taken to estimate the complex mixtures that comprise this additive involved, selective solvent extraction of the intact esters using a mixture of tetrahydrofuran and ethyl acetate, alkaline hydrolysis of the esters to liberate sucrose, and then GC-MS measurement of the liberated sucrose using GC-MS after acidic hydrolysis to glucose and fructose and then silylation. The method was developed to aid future estimates of intake of this food additive. The method determines the total sucrose esters content of a food sample and does not attempt to discrimination between individual sucrose esters when present as a mixture in a food sample. A single (average) factor is used to convert the liberated sucrose content into sucrose ester content. The method was applied to analysis of eight different food types (including bakery wares, sugar confectionery, dairy product, margarine, meat pies and a sauce) spiked with 0.5-1% of a mixture of three sucrose esters that spanned the hydrophilic/lipophilic balance (HLB) range 1-16. The limit of quantification was around 50 mg kg-1, which is more than adequate for these additives. The analytical recovery rate was 73-106% with an average of 91%. The precision of the method (RSD) was 6-18% (n = 3-20 for each food type) with an average RSD of 11%. The main analytical uncertainty is the conversion factor used to express sucrose ester content from the amount of sucrose liberated. The method is also applicable to sucroglycerides (E474).     

Dietary exposure of the Belgian population to emulsifiers E481 (sodium stearoyl-2-lactylate) and E482 (calcium stearoyl-2-lactylate)

A dietary exposure assessment of food emulsifiers E481 (sodium stearoyl-2-lactylate) and E482 (calcium stearoyl-2-lactylate) in the Belgian population was performed. Nationally representative food consumption data from the Belgian National Food Consumption Surveys 2004 (BNFCS2004) and 2014 (BNFCS2014) were used for calculations. A conservative approach (combining individual food consumption data with the maximum permitted level (MPL) of foods (tier 2), was compared with more refined estimates (combining individual food consumption data with actual concentrations measured in food products available on the Belgian market (tier 3)). Estimated daily intakes were compared to the acceptable daily intake (ADI) of the stearoyl-2-lactylates. The results of tier 2 demonstrated that 92% of the children (3–9 years), 53% of the adolescents (10–17 years), 15% of the adults (18–64 years) and 26% of the elderly (64–98 years) had a potential intake higher than the ADI. When replacing the MPL with maximum analysed concentration levels in foods, daily intake estimates decreased dramatically. The estimated daily intake of the food emulsifiers was below the ADI for all age groups, except for a small percentage of children (1.9%) for which the intake exceeded the ADI. The main contributors to the exposure of E481 and E482 were bread, rolls and fine bakery wares.     

牛乳蛋白对无麸质面包焙烤特性的改善作用

在添加水溶胶体和乳化剂的基础上,研究了三种牛乳蛋白(乳清浓缩蛋白,酪蛋白酸钠,脱脂乳粉)对无麸质面包(米粉、红薯淀粉)品质的改善作用。结果表明,乳清浓缩蛋白对无麸质面包品质的改善作用最为显著。加入15%乳清浓缩蛋白,无麸质面包比容增加19.4%,焙烤后2、24、48、72h面包硬度分别降低63.8%、80.0%、83.1%、71.2%。乳清浓缩蛋白有利于无麸质面团发酵过程中气孔的生成及发展,增加无麸质面包中小气孔及微小气孔的数量,提高面包气孔均匀性,可显著改善无麸质面包结构。     

EFFECT OF EMULSIFIERS AND FUNGAL α-AMYLASE ON RHEOLOGICAL CHARACTERISTICS OF WHEAT DOUGH AND QUALITY OF FLAT BREAD

Teftoon, a flat bread made of whole wheat flour, is prepared by hand sheeting of dough, followed by baking. Different emulsifiers, like lecithin, E471 (distilled monoglyceride) and E472 (diacetylated tartaric acid esters of mono- and digelycerid of fatty acids), were added to the flour at various levels ranging between 0.25 and 1.0% w/w, and it was observed that they improved the dough characteristics. Improvement in bread quality parameters, such as force to tear and sensory acceptability, were monitored. Fungal α -amylase was also incorporated into the flour at 5–20 g/100 kg flour basis alone and in combination with the emulsifier. The force required to tear the fresh bread was decreased with emulsifier and enzyme addition; however, E472 addition at 0.75% w/w of whole wheat flour gave the softest bread. The tear force of stored bread significantly increased with storage; however, bread containing E472 showed a less increase in tear force up to a period of 3 days. The sensory acceptability was found to be higher than that of the control bread for emulsifiers, and lower for enzyme at a concentration higher than 10 g/kg flour.

PRACTICAL APPLICATIONS

Flat bread is normally consumed fresh, but the staling phenomenon starts immediately after baking this kind of bread. Today, large-scale production and increased consumer demands for high-quality bread with long shelf life have created the need for functional food additives such as emulsifiers and α -amylase enzyme. Incorporation of emulsifiers and enzyme decreased the hardness of Taftoon bread. Emulsifiers and α -amylase enzyme enhanced the flat bread dough quality. The sensory acceptability also improved with the addition of emulsifiers. Optimizing the amount of emulsifiers and enzyme required for reduction of bread hardness is vital because the quality and price of the final product depend on this parameter.     

The role of buckwheat and HPMC on the breadmaking properties of some commercial gluten-free bread mixtures

Although the food industry has risen to the formulation challenges associated with removing gluten from dough, and a number of gluten-free (GF) products are now commercially available, many GF bread formulations are still based on pure starches, resulting in low technological and nutritional quality. The aim of this research was to evaluate the role of buckwheat and HPMC on the breadmaking properties of two commercial GF bread mixtures. A dehulled (DBF) and a puffed (PBF) buckwheat flour were used, and high substitution levels (40%) were tested, with the aim of improving the nutritional value of the final GF breads without decreasing their technological quality. Ten mixtures (2 commercial, 8 experimental) were evaluated. The inclusion of 40% DBF was demonstrated not to reduce but actually improve the baking performances of the commercial GF mixtures. Moreover, the presence of a small amount of PBF, as well as of HPMC, turned out to be useful in limiting both the diffusion and the loss of water from the bread crumb and the interactions between starch and protein macromolecules, resulting in a softer GF bread crumb and reduced staling kinetics during storage.     

Dietary exposure to aluminium of the Hong Kong population

A total of 256 individual food samples were collected in Hong Kong for aluminium testing. Most of food samples were analysed in ready-to-eat form. High aluminium levels were found in steamed bread/bun/cake (mean: 100–320 mg kg^?1), some bakery products such as muffin, pancake/waffle, coconut tart and cake (mean: 250, 160, 120 and 91 mg kg^?1, respectively), and jellyfish (ready-to-eat form) (mean: 1200 mg kg^?1). The results demonstrated that aluminium-containing food additives have been widely used in these food products. The average dietary exposure to aluminium for a 60 kg adult was estimated to be 0.60 mg kg^?1 bw week^?1, which amounted to 60% of the new PTWI established by JECFA. The main dietary source was “steamed bread/bun/cake”, which contributed to 60% of the total exposure, followed by “bakery products” and “jellyfish”, which contributed to 23 and 10% of the total exposure, respectively. However, the estimation did not include the intake of aluminium from natural food sources, food contact materials or other sources (e.g. drinking water). Although the results indicated that aluminium it is unlikely to cause adverse health effect for the general population, the risk to some populations who regularly consume foods with aluminium-containing food additives cannot be ruled out.     

From wheat sourdough to gluten‐free sourdough: a non‐conventional process for producing gluten‐free bread

Gluten‐free (GF) sourdough was prepared from wheat sourdough and analysed both in fresh (GFS) and dried forms (DGFS). The gluten content in each GF sourdough sample was <20 mg kg^?1. The dough leavening capacity and the properties of the bread samples were investigated and compared to those of bread prepared using bakery yeast (Saccharomyces cerevisiae). Two commercial rice‐based mixtures (different for the presence/absence of buckwheat flour) were used to prepare bread samples. In GFS, lactic acid bacteria (LAB) and yeasts were found in amounts corresponding to 10⁸ and 10⁷ CFU g^?1, respectively, whereas both LAB and yeasts were detected in lower amounts (about 10⁶ CFU g^?1) in DGFS. When used in bread‐making, both GFS types produced significant dough acidification and exhibited good dough development during proofing, resulting in loaves with specific volume values between 3.00 and 4.12 mL g^?1, values similar to those obtained for reference bread (3.05÷4.15 mL g^?1). The use of GFS was effective in lowering the bread staling rate during storage for up to 7 days.     

High-performance liquid chromatography and gas chromatography to set the analysis method of stearoyl lactylate,a food emulsifier

Food Science and Biotechnology - Stearoyl lactylates (SLs, E481/E482) and their sodium and calcium salts are emulsifiers commonly used as food additives. This study was performed to set the...     

Effects of native and enzymatically hydrolysed soya and oat lecithins in starch phase transitions and bread baking

The effects of oat and soya lecithins and their hydrolysates on crystallisation of wheat starch gel and on bread structure were studied. In baking studies the lecithins were compared with commonly used commercial emulsifiers. Soya lecithin hydrolysate retarded starch gel crystallisation and bread staling as effectively as the best commercial emulsifiers. The oat lecithins were interesting. They did not affect significantly the starch gel crystallisation but both of them retarded bread staling much more effectively than the soya lecithin. Oat lecithins were as good as the commercial Amidan indicating that glycolipids in oat lecithins slowed bread staling. © 1998 SCI.     

Rheological properties of gluten-free bread formulations

In this study, the rheological properties of rice bread dough containing different gums with or without emulsifiers were determined. In addition, the quality of rice breads (volume, firmness and sensory analysis) was evaluated. Different gums (xanthan gum, guar gum, locust bean gum (LBG), hydroxyl propyl methyl cellulose (HPMC), pectin, xanthan–guar, and xanthan–LBG blend) and emulsifiers (Purawave^™ and DATEM) were used to find the best formulation for gluten-free breads. Rice dough and wheat dough containing no gum and emulsifier were used as control formulations. The rice dough containing different gums with or without emulsifiers at 25 °C showed shear-thinning behavior with a flow behavior index (n) ranging from 0.33–0.68 (except pectin containing samples) and consistency index (K) ranging from 2.75–61.7 Pa sⁿ. The highest elastic (G′) and loss (G″) module were obtained for rice dough samples containing xanthan gum, xanthan–guar and xanthan–LBG blend with DATEM. When Purawave^™ was used as an emulsifier, dough samples had relatively smaller consistency index and viscoelastic moduli values compared to DATEM. The viscoelastic parameters of rice dough were found to be related to bread firmness. Addition of DATEM improved bread quality in terms of specific volume and sensory values.     

Soluble dietary fibres in Jerusalem artichoke powders: composition and application in bread

Powders of tubers from Jerusalem artichoke (Helianthus tuberosus, L.), cultivar Gigant, of different harvesting times (autumn and spring) were applied in bakery products, particularly in wheat/rye bread. The quality of this bread was compared to bread with cereal flours substituted with commercial products as Raftilin ST and Raftilose P95. Compared to standard and substituted bread, Jerusalem artichoke bread shows a high quality in organoleptic evaluation (grade I with 36.5 and 37.5 scores). In utilised Jerusalem artichoke powders (JAPs) the amount of fructan (inulin) hydrolysis to fructose during the baking process depends on its initial degree of polymerisation (dp). With JAP of autumn harvest (fructan: dpn = 9.9, dpw = 21.8) less fructose (24.6%) is formed than with those of spring harvest (fructan: dpn = 4.9, dpw = 7.1) (40.7%). Compared to this bread, substitution with commercial products Raftilin ST (inulin: dpn = 8.4, dpw = 17.4) and Raftilose P95 (fructo-oligosaccharides: dpn = 2.7, dpw = 3.0) yields 11.9% and 45.8% of fructose upon total hydrolysis, respectively. The loss of fructan content by the bakery process is 38% in bread with JAP of autumn and 43% in bread with JAP of spring harvest; Raftilin ST- and Raftilose P95-bread come up with loss of fructan content of 35% and 47%, respectively.     

Factors affecting the quality of Arabic bread—additional ingredients

The effect of ascorbic acid and potassium bromate, reducing agents (L -cysteine and sodium metabisulphite), emulsifiers (sodium stearoyl-2-lactylate (SSL) and sucrose fatty acid esters) and a combination of these additives on the quality of Arabic bread has been studied. Statistical analysis indicated that the internal quality parameters of Arabic bread significantly deteriorated with the addition of ascorbic acid and potassium bromate. The addition of reducing agents has the advantage of reducing mixing time and improving dough sheeting quality. SSL (3 g kg^?1) improved the quality of Arabic bread especially after overnight storage. Sucrose ester F-110 had an adverse effect on most aspects of Arabic bread quality.     

Oxidative stability of structured lipids

The current popularity on structured lipids (SLs) is well known because they are presented as improved lipids from the technological or nutritional point of view. Regardless of the demonstrated health or therapeutic properties of a novel SL, it is important to consider that whether such lipid shows instability, deteriorates the quality of the food, worse the sensory attributes or reduce its self-life, its production for the food industry field would not be worthwhile. The current review attempts to collect the reported information so far on SLs regarding their quality and oxidative stability as affected by diverse parameters, as well as the impact of SLs on the oxidative stability of food model systems or real food products. In general, most researchers have reported a worse oxidative stability of SLs with respect to original oils, mainly related to the loss of endogenous antioxidants, due to that, both synthetic and natural antioxidants are being tested in SLs. Furthermore, other diverse parameters are involved in the stability of SLs, such as the conditions of production technology, the oil sources, the positional distribution of fatty acids or the unsaturation degree of lipids. Therefore, due to the huge diversity of factors affecting SLs, stating general and definitive conclusions on their oxidative behavior is difficult since complicated and controversial results are reported.     

Soybean Hulls as an Iron Source for Bread Enrichment

Soybean hulls, a concentrated source of iron, may have potential as a source of iron fortification in baked products. Retention of ⁵⁹Fe in rats from white bread containing intrinsically labeled soybean hulls did not differ significantly (p<0.05) from extrinsically labeled white bread fortified with bakery grade ferrous sulfate (70.4 and 63.1%, respectively). Physical and sensory evaluations of bread containing up to 5% soybean hulls did not differ from white bread in loaf volume, cross-sectional area, tenderness or overall acceptance. These results suggest that soybean hulls are a good source of available iron and may be added to bakery products without deleterious effects in baking performance and sensory acceptability.     

小麦粉中添加植酸对馒头品质的影响

植酸是一种新型的天然食品添加剂,作为抗氧化剂、防腐剂、发酵促进剂或螯合剂广泛用于食品工业。试验利用3个不同筋力梯度的小麦粉,按0.005%、0.025%、0.05%、0.1%、0.15%、0.2%(植酸与制造馒头小麦粉质量比)的比例添加植酸后制作馒头,测定其质构特性并做馒头感官评价试验。结果表明,随着植酸添加比例的增加,馒头的体积和评分值均有小幅度下降,但是无论馒头瓤和皮的色差都有小幅度的增白现象。硬度、黏着性、胶着性、咀嚼性和体积与植酸添加量呈显著线性负相关,其余性状与植酸添加量的相关性不显著。但总的来说,添加植酸对馒头的品质特性没有起到显著性的影响。     

Irish National Food Ingredient Database: application for assessing patterns of additive usage in foods.

Patterns of food additive usage in the Irish food supply and changes in patterns of usage between 1995-97 and 1998-99 were assessed by means of an Irish National Food Ingredient Database (INFID). Of the 300 additives permitted for use according to the European Union food additives Directives, some 54% were recorded in foods in INFID. Colours, emulsifiers and acids were the most frequently used additive categories, representing 18, 13 and 12% of the total additives used, respectively. Colours were most commonly recorded in sauces (n = 182 brands, 26% of sauces), emulsifiers were most commonly recorded in biscuits (n = 181 brands, 47% of biscuits) and acids were most commonly recorded in sauces (304 brands, 43% of sauces). Carotenes (E160a), Annatto (E160b), mono- and diglycerides of fatty acids (E471) and citric acid (E330) were the most commonly used colour, emulsifier and acid, respectively. All diet soft drinks (n = 37), low-fat spreads (n = 25) and liver patés (n = 10) recorded the use of at least one additive. When expressed in terms of the number of brands that contain additives, sauces (n = 522, 73% of sauces), biscuits (n = 323, 84% of biscuits) and preserves (n = 321, 85% of preserves) were ranked highest. For most categories of additive (n = 24), there appeared to be a minimal change in qualitative additive usage between 1995-97 and 1998-99. However, there was a significant increase in the frequency of use of emulsifiers (p < 0.001), acids (p < 0.01), sweeteners (p < 0.05) and acidity regulators (p < 0.05), and a significant decrease in the frequency of use of antioxidants (p < 0.05) during the period 1998-99 compared with 1995-97. Despite changes in additive usage patterns, it appeared that changes in the types of brands on sale between both periods were more apparent than actual changes in qualitative ingredient formulations across brands, as some 17% of brands that were on sale in 1995-97 were no longer on sale in 1998-99.     

低分子添加剂法抑制焙烤食品中丙烯酰胺的研究现状

丙烯酰胺属于对人可能致癌物质,其主要产生于食品加工过程中的Maillard反应。目前,关于丙烯酰胺的研究主要集中于油炸食品,但关于焙烤食品如面包、饼干、蛋糕等方面的研究较少,而且由于工艺的不同,油炸食品中可行的方法并不能直接应用于焙烤食品。使用低分子添加剂是目前较为新兴的抑制丙烯酰胺的方法,其在油炸食品及焙烤食品中均具有良好的效果,且对产品风味的影响较小。本文总结了近些年学者们通过使用低分子添加剂降低焙烤食品中丙烯酰胺含量的实践及研究。