Effect of polyphenols on mixing properties and solvent retention of wheat flour doughs

BACKGROUND

The effect of polyphenol addition on dough mixing properties and flour functionality was examined using flours from different wheat varieties.

RESULTS

Both the mixograph and farinograph experiments showed that polyphenol addition affected dough stability and optimum mixing time. These effects were most apparent in hard wheat flour with the addition of catechin. Water absorption was dependent on wheat variety (P < 0.0001) but not on the addition of polyphenols (P = 0.54). Except for the 5 g kg^-1 sodium carbonate solvent retention capacity (SRC), SRC values of the flours were dependent on wheat variety but not on polyphenol addition. However, 5 g kg^-1 sodium carbonate SRC was significantly increased by the addition of caffeic acid and catechin. Since sodium carbonate SRC is associated with damaged starch levels, further investigations are needed to see how polyphenols influence either the absorption of a sodium carbonate solution or the starch itself.

CONCLUSION

Polyphenol addition affected dough stability and optimum mixing time. Addition of catechin to hard wheat flour was most effective. Water absorption and SRC values except for 5 g kg^-1 sodium carbonate solvent were affected by the wheat variety, but not by polyphenol addition. © 2021 Society of Chemical Industry.

Lipid Oxidation in Low-moisture Food: A Review

Overly high intake of saturated fat is an international problem contributing to global health issues. Low-moisture snacks account for a nutritionally significant proportion of the saturated fat in the diet, making these foods a key target for improving consumers' health. However, it is not currently feasible to maintain the same oxidative shelf life when replacing saturated fats with unsaturated fats, which are generally perceived to be more heart-healthy. This article summarizes current theories and available research on lipid oxidation in low-moisture foods in order to lay the groundwork for new lipid oxidation rate-reduction strategies. Research deficits needing attention and new methods for assessing lipid oxidation in low-moisture foods are also discussed.

Influence of phytic acid and its metal complexes on the activity of pectin degrading polygalacturonase

Polygalacturonase is one of the important requirements of different microorganism to cause pathogenicity and spoilage of fruits and vegetables that involved in degradation of pectin during plant tissue infections. In current study, 20 mM phytic acid inhibited 70% activity of polygalacturonase. The effect of different concentration of metal ions such as Cu(+2), Al(+3) and V(+4) were studied separately and it was found that the 20 mM of these metal ions inhibited 37.2%, 79%, and 53% activity of polygalacturonase, respectively. Finally, the complexes of phytic acid and these metals ions were prepared and 1:1 ratio of phytic acid and metal ions complexes showed maximum inhibitory activity of enzyme as compared to complexes having 1:2 and 1:3 ratio except phytate-copper complexes which showed no inhibitory effect on the activity of polygalacturonase.

Evaluation of antioxidant, rheological, physical and sensorial properties of wheat flour dough and cake containing turmeric powder

The effects of addition of turmeric powder (0%, 2%, 4%, 6% and 8%) were examined in order to obtain an antioxidant-enriched cake with good physico-chemical and sensorial properties. The rheological properties of doughs were evaluated using dynamic rheological measurements. Physical properties, curcumin content, radical scavenging activity (RSA-DPPH assay) and sensory analysis (hedonic test) of the supplemented cake were determined. Addition of turmeric powder up to 8% caused significant changes on dough characteristics and on cake rheological properties. The highest curcumin (203 mg/kg) and RSA-DPPH activity (45%) were achieved in the cake having the highest percentage of turmeric powder (8%); however, this sample showed the worst results regarding the rheological properties. Moreover, by sensory evaluation this cake sample was not acceptable. A 6% substitution of wheat flour with turmeric powder showed acceptable sensory scores which were comparable to those of 0-4% turmeric cakes. This indicated that up to 6% level of turmeric powder might be included in cake formulation.

Effect of phenolic acids on the rheological properties and proteins of hard wheat flour dough and bread

BACKGROUND

The effects of different phenolic acids on the rheological properties and gluten proteins of hard wheat flour dough and bread were investigated. Caffeic, ferulic, syringic and gallic acids were each blended with hard wheat flour at a concentration of 4.44 µmol L(-1) g(-1) flour.

RESULTS

Mixing time and tolerance were reduced with the addition of phenolic acids. The phenolic acids reduced the maximum resistance to extension (R(max)) and increased the extensibility of dough, with effects in the following order: gallic < syringic < ferulic < caffeic acid. The effect on R(max) was more pronounced in overmixed dough. Loaf volume was most significantly decreased with the addition of caffeic acid. Extraction of sodium dodecyl sulfate-soluble high-molecular-weight proteins was increased in both mixed and fermented doughs by the addition of ferulic and caffeic acids. The order of influence of the phenolic acids on the rheological properties and protein structure of dough and bread was consistent with that of their antioxidant activity.

CONCLUSION

The addition of caffeic and ferulic acids reduced R(max) and increased the extensibility of hard wheat flour dough by modifying the high-molecular-weight gluten, which resulted in decreased bread volume.

Antioxidant activity of hard wheat flour, dough and bread prepared using various processes with the addition of different phenolic acids

BACKGROUND

The purpose of this study was to evaluate the effect of baking process on the antioxidant activity of different phenolic acids. Antioxidant potential was determined using the β-carotene-bleaching activity assay, and free phenolic acid levels were determined by high-performance liquid chromatography. Four phenolic acids, caffeic acid, ferulic acid, syringic acid and gallic acid, were mixed with wheat flour at a concentration of 4.44 µmol/g of flour.

RESULTS

Type of phenolic acid and processing affected antioxidant activity. Of the phenolic acids, caffeic acid had the most pronounced antioxidant effect. The ranking of phenolic acids in terms of their antioxidant activity in fermented dough and bread was similar to that before processing, i.e. syringic acid < gallic acid < ferulic acid < caffeic acid. The content of ferulic acid was greater than that of the other phenolic acids after baking. Antioxidant activity and free phenolic acid content were reduced by mixing but recovered after fermentation and baking. Phenolic acid recovery after baking was 74-80%.

CONCLUSION

Phenolic acids retain their antioxidant activity after the baking process, which has potential health benefits for consumers. Elucidation of interactions between the baking process and phenolic acids is important for the development of functional foods.