Stability of docosahexaenoic acid and eicosapentaenoic acid in breads after baking and upon storage

Wholemeal bread and white bread were prepared by substituting shortening with refined menhaden fish oil (0.5%, 1.0% and 1.5% w/w). The stability of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were evaluated over 5 days of storage through gas chromatography (GC) analysis along with peroxide and anisidine value determinations. Sensory analysis was also performed by evaluating the fishy flavour, palatability and palatability differences compared to the control bread upon storage. The recoveries of EPA and DHA in breads after baking were 68.7%–72.8% with no further significant changes (P < 0.05) upon storage for both types of breads. Results from GC analyses correlated well with peroxide and anisidine value analyses, which showed relatively low values throughout the storage time. Omega‐3‐fatty acids from Menhaden fish oil can be incorporated into breads by substituting the shortening at a fish oil level of 0.5% (w/w) with acceptable palatability even after a 3‐day storage period.     

Partial substitution of pork backfat with extra-virgin olive oil in 'salami' products: effects on chemical, physical and sensorial quality

The effects on chemical, physical and sensory quality of the partial substitution of pork backfat with extra-virgin olive oil were studied in 'salami' products. Four 'salami' formulations, with 15% total fat, were prepared, in which 0, 33.5, 50 and 66.5% of pork backfat was substituted with extra-virgin olive oil. The partial pork backfat substitution with extra-virgin olive oil did not substantially affect the chemical, physical and sensorial characteristics of products, with the exception of water activity and texture. With regard to both oxidation and loss of organoleptic quality, the addition of extra-virgin olive oil, rich in mono-unsaturated fatty acids, did not decrease the shelf-life. The difference between samples with and without extra-virgin olive oil was a piquant note detected in the oil-added 'salami'. The formulation with 5% olive oil, corresponding to 33.3% substitution of pork backfat with olive oil, was judged best of all formulations. The results show that it is possible to produce this type of product, of good taste, similar to the traditional one, but with healthier features.     

Survival of micro-organisms in extra virgin olive oil during storage

When newly produced from the grinding of the olive fruits, olive oil contains solid particles and micro-drops of vegetation water which settle during the preservation of the product. The present research has demonstrated that, together with the suspended material in the extra-virgin olive oil, there are numerous micro-organisms, primarily yeasts. Fungi belonging to the genus Aspergillus, were occasionally observed, while bacteria were not found. When olive oil was artificially inoculated with Candida wickerhamii isolated from the same habitat, it was found that the yeasts were able to grow in the micro-drops of vegetation water or distilled water suspended in the olive oil. Furthermore, it was shown that the partial elimination of the sediments in the oil, carried out with cotton filtration by the bottling companies, allows an appreciable reduction of the number of micro-organisms present in the extra-virgin olive oil.     

Determination of apolar and minor polar compounds and other chemical parameters for the discrimination of six different varieties of Tunisian extra-virgin olive oil cultivated in their traditional growing area

A study on the characterization of Tunisian extra-virgin olive oil varieties produced in their place of origin has been carried out. Due to the influence of the genotype and environmental, agronomic and technological factors on the chemical composition of olive oil and its quality, all the olives studied were collected on the same season, and the oil was obtained under the same processing technique. Several analyses were performed to characterize the different olive oils: free acidity, peroxide value, fatty acid composition, radical scavenging activity, Rancimat assay, pigments content and phenolic compounds by HPLC–MS. In order to evaluate all the results obtained (36 parameters for each variety), different statistical analyses were used to discriminate the extra-virgin olive oil varieties: one-way analysis of variance was performed to check significant differences among cultivars (p ≤ 0.05); PCA was applied to the data showing that variables such as oleic, linoleic, quinic and vanillic acids, apigenin, luteolin, taxifolin, oleuropein aglycon, pinoresinol acetate, elenolic acid and oxidative stability allowed discriminating among the different varieties of extra-virgin olive oil studied. Besides, LDA model was able to classify the samples depending on their geographical origin in Tunisia (North, Centre and South).     

Edible and non-edible olive oils discrimination by the application of a sensory olfactory system based on tin dioxide sensors

An array of semiconductor sensors has been developed to discriminate virgin olive oil samples based on their organoleptic characteristics. The multisensor, developed at laboratory, is composed by 14 sensing elements of tin dioxide thin layers (doped with Cr and In, and undoped) deposited by the reactive sputtering technique. The sensors are stable and show good repeatability. Off-flavors and extra-virgin olive oil samples, taken at the outlet of the vertical centrifuge of a small experimental olive oil mill and sensory evaluated, have been used. A good discrimination of edible (extra-virgin and virgin) from non-edible (lampante) olive oils has been obtained through the statistical method of principal component analysis (PCA).     

FLAVOR PROPERTIES OF PAN AND PITA BREADS MADE FROM RED AND WHITE HARD SPRING WHEATS

ABSTRACT

Red and white wheat comparisons have not always shown consistent flavor differences. The objective was to compare flavor properties of whole wheat pan and pita breads made from white and red Canadian hard spring wheats. Flavor attributes were defined by trained panelists who marked intensities using 15‐cm line scales. Pan bread made from BW275 and Kanata had significantly lower wheat and wheaty aftertaste intensity than AC Domain (red) and RL4863. Pita bread from Kanata had significantly higher sweet intensity than RL4858, Snowbird and AC Domain (red). Principal component analysis accounted for 74–75% of the variance in both bread types. Biplots showed that some of the white wheat breads tended to be sweeter with less wheaty and bitter with wheaty, bitter and sour aftertastes. Red wheat breads tended to be less sweet, more wheaty and bitter with wheaty, bitter and sour aftertastes. Higher wheaty flavor intensity was associated with visually darker breads.

PRACTICAL APPLICATIONS

The study revealed that there were distinct flavor differences in pan bread and pita bread made from red and white wheats. The sweeter and milder flavor observed for some white wheats could be a marketing advantage for these newly developed wheats. In pan and pita bread products targeted to consumers that dislike the often wheaty and bitter taste of whole wheat products made from red wheat, white wheat derived whole wheat products with their milder taste may be more acceptable.     

Dry-fractionation of wheat bran increases the bioaccessibility of phenolic acids in breads made from processed bran fractions

This study evaluated the potential of using ultra-fine grinding and electrostatic separation of wheat bran as methods to improve the bioaccessibility of para-coumaric acid (pCA), sinapic acid (SA) and ferulic acid (FA) from bran-rich breads. Bran fractions were produced and used to bake white bread, whole-grain bread, and seven different bran-rich breads. The influence of bran particle size and bread composition on the bioaccessibility of pCA, SA and FA was studied using a dynamic computer-controlled in vitro gastro-intestinal model. The amount of bioaccessible phenolic acids was higher in whole-grain bread and bran-rich breads than in white bread, and the finer the bran particles in bran-rich breads, the more bioaccessible the phenolic acids. The highest amounts of bioaccessible phenolic acids were observed for two of the fractions obtained by electrostatic separation of ground bran. Only the free and conjugated phenolic acids forms were found to be bioaccessible, and the bioaccessibility of SA was much higher than that of FA, due to the higher solubility of SA. This study demonstrated that the use of bran fractionation to reduce the particle size, or to include only some parts of the bran in foods, can help developing grain-based products with increased nutritional potential.     

Development and evaluation of products from cassava flour as new alternatives to wheaten breads

Egg white with margarine, and xanthan gum, have been used to produce alternative breads from cassava flour fortified with 200 g kg^?1 soya flour. All the additives increased the amount of air entrapped in the cassava batters at the mixing stage, as indicated by their lower batter densities. The lower the batter density the higher was the maximum gas retention volume attained in the 60 min fermentation stage. However, final loaf volume also depends on the stability of the batter; egg white primarily acts as a stabiliser. Margarine, and more significantly egg white, reduced the extent of starch gelatinisation and solubilisation in the bread. Breads made with locally available egg white and margarine are sensorily acceptable to Nigerian consumers and have very good keeping qualities.     

Assessing Influence of Protein Source on Characteristics of Gluten-Free Breads Optimising their Hydration Level

Most gluten-free products have lower protein content than their counterparts with wheat flour. The addition of exogenous proteins could not only be a good option to compensate for this reduction but also a tool to create gluten-free products rich in protein. However, the different water-binding capacities of proteins modify dough rheology, which also affects bread volume. Therefore, this study aimed to analyse the incorporation of a high percentage (30%) of several proteins (rice, pea, egg white and whey protein) in gluten-free breads whose hydration levels were adjusted for each protein to achieve the maximum volume. In this way, the breads with vegetal proteins required a higher amount of water than the breads with animal proteins. Moreover, all enriched breads exhibited lower maximum volume values than control, and the ones with whey protein presented the lowest volumes overall. From these results, the rheological behaviour and characteristics (colour, texture and weight loss) of optimised doughs and breads were measured. The doughs with whey protein presented the highest G′ and G″ values due to their low hydration level, and the ones with egg white protein were very watery. Regarding colour, the addition of protein led to darker crusts, with the ones with whey protein being the darkest. With respect to the control, breads with animal proteins exhibited higher hardness, especially with whey protein, while the ones with vegetal proteins did not present significant differences.     

Selenium levels in breads from Sakarya,Turkey

Selenium (Se) is an important trace element for human and animal health. It accumulates in wheat and corn, which is consumed mostly as bread. The Turkish population consumes mainly white wheat, whole wheat (brown bread) and corn breads. In this study, samples of these breads were collected from six different bakeries in the city of Sakarya, and their selenium levels were determined by ICP–OES after a chemical digestion. It was found that average selenium levels in white wheat, whole wheat and corn breads were 1149, 1204 and 2023?µg/kg, respectively. The results are compared with daily recommended intake and upper tolerable levels for selenium.     

Modification of gluten-free sorghum batter and bread using maize, potato, cassava or rice starch

Gluten-free sorghum bread was made from cassava, maize, potato or rice starch and sorghum in the ratios 10:90, 20:80, 30:70, 40:60 and 50:50. The other baking ingredients, on flour-weight-basis, were water (100%), sugar (6.7%), egg white powder (6%), fat (2%), salt (1.7%) and yeast (1.5%). Increasing starch content changed the batters’ consistencies from soft doughs to thin pourable batters. Increasing starch content decreased crumb firmness and chewiness, and increased cohesiveness, springiness and resilience of all breads. Cassava-sorghum and rice-sorghum breads had better crumb properties than maize-sorghum or potato-sorghum breads. Although the crumb properties of all breads declined (i.e. firmness and chewiness increased; cohesiveness, resilience and springiness decreased) on storage, the formulation containing 50% cassava starch retained the best overall texture.     

Folate fortification of white and whole-grain bread by adding Swiss chard and spinach. Acceptability by consumers

The aim of this work was to study the effect of bread-making on the content of endogenous folate of white and whole-grain bread fortified with either Swiss chard or spinach at 20 g/100 g and 40 g/100 g measured by HPLC (H4-folate and 5-CH3-H4-folate); and to assess the sensory acceptability of folate-fortified breads compared to non-fortified breads. The fortification of breads with 20 g/100 g and 40 g/100 g vegetables significantly (p < 0.001) increased the total folate content (from 19.9 to 57.9 μg/100 g in white bread and from 37.4 to 75.5 μg/100 g in whole-grain bread). Moreover, 40 g/100 g Swiss chard- and spinach-fortified breads obtained higher scores in overall acceptability than 20 g/100 g fortified or control bread for both white and whole-grain breads. The consumption of two servings (56 g each) per day of 40 g/100 g fortified bread would meet the daily folate requirements by 14.3–21.8% in adults and 9.6–14.5% in some special states like women of child-bearing age.     

Effects of hull-less barley flour and flakes on bread nutritional composition and sensory properties

Barley is a desirable food ingredient, with health benefits provided by a β-glucan fibre fraction. A hull-less barley flour and flakes were incorporated into white and wholegrain wheat bread in quantities usually applied in practice. The breads were evaluated for nutritional composition and sensory properties and compared to standard products as controls. The supplemented breads were high in fibre, zinc and selenium content. It was estimated that a 300-gram daily portion of such breads could meet up to 40% of dietary recommended intakes for selenium and 70–75% of recommended daily values for β-glucan. Regarding sensory quality, the only significant differences (p < 0.05) were higher taste and lower volume in the white supplemented breads and lower crumb elasticity in the white bread made with barley flour. Hull-less barley can substantially contribute to an adequate intake of selenium and β-glucan. In addition, supplemented breads were not found to pose a significant risk, with regard to excessive intakes of heavy elements (Pb, Cd, As).     

Oxidative stability of olive oil after food processing and comparison with other vegetable oils

The use of olive oil showed an important protection of meat and potatoes when compared with other vegetable oils, with sunflower oil samples being oxidised after 60 min of processing at 180 °C. Olive oil samples were not oxidised, independently of the olive oil quality used. Shelf life was longer for extra-virgin olive oil containing samples and this fact was positively correlated with their higher phenolic content. The radical-scavenging activity of extra-virgin olive oil was higher than for other olive oil samples and was also positively correlated with the phenolic content of the oil. Seed oil antioxidants showed little capacity in delaying the oxidative degradation of seed oils and meat processed with them. However, tocopherol content and the identity of tocopherols present in the oil were shown to have a more important role in the oxidative stability of seed oils than the fatty acid composition.     

Application of Response Surface Methodology to the Development of Rice Flour Yeast Breads: Objective Measurements

A gluten-free wheat bread replacement was developed from rice flour (80%) and potato starch (20%). Using objective measurements as responses, response surface methodology was utilized to find carboxymethylcellulose (CMC)-hydroxypropylmethylcellulose (HPMC)-water combinations which could successfully replace gluten in the rice flour yeast breads from each of three rice flours. CMC and water had the greatest effect on the responses measured; HPMC had the least. Rice bread formulations were found that resulted in breads which met wheat (white) bread reference standards for specific volume, crumb and crust color, Instron firmness and % moisture.     

Quality and antioxidant property of buckwheat enhanced wheat bread

Common buckwheat (Fagopyrium esculentum Moench) was used to substitute 15% of wheat flour to make buckwheat enhanced wheat breads. Proximate composition, physical quality, functional components and antioxidant properties of buckwheat enhanced wheat breads were analysed and compared with those of white bread. Specific volumes of three breads were 6.10–6.75 cm³/g. Buckwheat enhanced wheat bread showed lower lightness and whiteness index values and higher redness and yellowness values. On a seven-point hedonic scale, all sensory results were 5.33–5.91, indicating that three breads were moderately acceptable. No differences were found in appearance, colour and overall sensory attributes for three breads, whereas both buckwheat enhanced wheat breads were rated higher in flavour and mouth feel. Buckwheat enhanced wheat bread contained more rutin and quercetin as expected. Buckwheat enhanced wheat bread was good in antioxidant activity, reducing power and 1,1-diphenyl-2-picrylhydrazyl radical scavenging ability with unhusked buckwheat enhanced wheat bread being the most effective. Overall, buckwheat enhanced wheat bread could be developed as a food with more effective antioxidant properties.     

Comparison of glycemic index of spelt and wheat bread in human volunteers

The assessment of the glycemic index (GI) seems to be an important parameter to take into account in order to better understand the physiologic effects of foods with high carbohydrate levels. Among cereals, which are major sources of carbohydrates, spelt (Triticum spelta L.) has been considered as particularly interesting from a nutritional point of view. The aim of this study was to evaluate in vivo the GI of white spelt bread in healthy subjects. The wheat (Triticum aestivum L.) white bread was used as reference food. To avoid differences in the production of both breads, spelt and wheat breads were baked under the same controlled conditions. Results showed that the glycemic profile of spelt white bread was not different from that of wheat white bread (GI of 93 ± 9). The area under the glycemic curve significantly and negatively correlated to fasting glycemia and carbohydrate intake during evening meals preceding the test. In conclusion, the glycemic response to spelt bread was similar to that of wheat bread. However, in order to avoid more inter-individual variability, our data supports the importance to propose standardised carbohydrate content for the last meal before evaluating the GI of food.     

Fermentation Process and Grain Structure of Baked Breads from Frozen Dough Using Freeze-Tolerant Yeasts

The fermentation process for frozen doughs using freeze‐sensitive (Saccharomyces cerevisiae, Kyowa for sweet bread; S. cerevisiae, FC for white bread) and freeze‐tolerant (S. cerevisiae, YF for sweet bread) yeasts was traced by magnetic resonance imaging (MRI). Grain network structures of baked breads were also visualized by MRI. Prefermentation before freezing, punching and remolding, or resheeting and molding treatments increased loaf volume by 10 to 110% for the baked breads using freeze‐tolerant yeast, while these treatments decreased loaf volume by 70% using freeze‐sensitive yeast. The first fermentation before freezing and the second fermentation with punching or resheeting after thawing are useful for obtaining good quality breads from frozen dough using freeze‐tolerant yeast.     

Effect of fermentation conditions on bread staling kinetics

The effects of yeast dose, temperature and fermentation time on bread volume, bread density, bread texture (firmness, cohesiveness, resilience, springiness and gumminess) and their change during staling were analysed. Thus, changes in the texture profile (TP) parameters as bread aged were modelled and their initial values and their variation rate were obtained. In white and whole breads, the longer the fermentation time and the higher the yeast dose, the lower the firmness and the firming rate. The fermentation temperature only affected the initial firmness in whole breads. Significant linear correlations were found between bread density and volume (r ² = 0.94 in white bread; r ² = 0.96 in whole bread), between density and the initial firmness (r ² = 0.88 in white bread; r ² = 0.61 in whole bread), and between the first two parameters and the firming rate. Between density and firming rate r ² obtained was 0.72 in white bread and 0.32 in whole bread and between volume and firming rate r ² obtained was 0.58 in white bread and 0.29 in whole bread.