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Slaviša Stajić, Nikola Stanišić, Steva Lević, Vladimir Tomović, Slobodan Lilić, Danijela Vranić, Marija Jokanović and Dušan Živković

Abstract

The aim of this study was to determine the extent of changes in physico-chemical and sensory properties of dry fermented sausages where pork backfat was partly replaced by flaxseed oil used as liquid (FXL), after encapsulation (FXE), and pre-emulsified with alginate (FXA) and soy protein isolate (FXI). During production and storage, similar pH values of all products were observed. FXL sausages had significantly lower (p<0.05) weight loss which led to significantly higher moisture content, significantly lower fat content, hardness and chewiness. Also, FXL sausages had the lowest grades in terms of sensory attributes, such as colour, odour, taste, texture and overall acceptability. Flaxseed oil preparations affected the parameters of instrumental colour analysis of sausages. All modified products had significantly higher yellowness (relative to control) and FXI sausages relative to other modified products. Regarding consumer sensory evaluation, FXA sausages stood out among modified products because all other modified products had significantly lower grades relative to control. The thirty-day storage period did not lead to significant changes (p>0.05) in any of the observed sensory characteristics.

Open access

Veronika Kuchtová, Zlatica Kohajdová, Jolana Karovičová and Michaela Lauková

Abstract

This study is oriented to the effect of the incorporation of grape skins and grape seeds (0, 5, 10, and 15% to weight of flour) obtained from a red grape on the rheological properties of wheat dough, and on qualitative parameters and sensory properties of the prepared cookies.

With regarding to dough rheological parameters, addition of grape skins concluded in increased water absorption and reduced dough stability. The opposite effect to these parameters was observed after inclusion of grape seeds. Moreover, it was found that the addition of both types of grape skin and seed preparations resulted in reduced volume, thickness and decreased hardness of cookies. Also, it was recorded, that the addition 10% of grape seeds and 15% of grape skins significantly decreased fracturability of cookies. The results of sensory analysis showed that the cookies incorporated with grape skins and grape seeds up to a level of 5% resulted in products with good overall acceptability accounting for 87.44% and 91.44%, respectively.

Open access

Sofía Guillén, Rosa Oria and María Luisa Salvador

Abstract

The aim of this study was to evaluate the effect of cooking temperature on the in vitro starch digestibility of four varieties of rice: Basmati, Calrose, Arborio and Bomba. Total starch, resistant starch and amylose contents were determined in raw and cooked samples. The in vitro kinetics of starch hydrolysis were also determined, and the hydrolysis and glycemic indexes were estimated. Both the initial amylose content and the cooking temperature had a significant influence on the resistant starch content. Rice cooked at 95ºC retained a higher resistant starch content than rice cooked at 100ºC. The in vitro study of starch hydrolysis showed that hydrolysis tended to be slower and less complete for rice with a higher amylose content and for rice cooked at a lower temperature. Cooking rice at 95ºC instead of 100ºC reduced the estimated glycemic index by approximately 10% for the varieties tested.

Open access

Pablo A. Sobral, J. Sebastian Henao Ossa, Gonzalo G. Palazolo and Jorge R. Wagner

Abstract

This paper focuses on the comparative study of emulsifying properties of dried tofu-whey, dried soy-whey and their isolated proteins. Oil-in-water emulsions were prepared at equivalent protein concentration (0.1, 0.5 and 1.0 g/100 mL), using sunflower oil as lipid phase (oil mass fraction = 0.33). Tofu-whey and soy-whey were dehydrated by freeze-drying (LTW and LSW, respectively) or thermal-drying (DTW and DSW, respectively). Moreover, a heated LSW sample in anhydrous condition (h-LSW) was included. The emulsion formation and stability at rest was evaluated using a vertical scan analyzer, according to multiple light scattering theory, particle size and oiling off measurements. Even though the stability to gravitational separation and coalescence increased with increasing protein concentration, freeze-dried whey samples exhibited a higher ability to form and stabilize emulsions respect to that of thermally-dried ones, especially for those obtained from soy-whey. Moreover, h-LSW emulsions were more stable than that of LSW sample presumably due to protein glycosylation. The global emulsion stability decreased in the order: LTW>DTW>h-LSW>LSW>DSW. Moreover, at equivalent protein concentration in the continuous phase, the isolation of proteins from lyophilized whey-samples by treatment with cold acetone (LTW-P, LSW-P and h-LSW-P, respectively) improved their emulsifying properties. Again, this improvement was more pronounced for samples obtained from soy-whey, probably due to partial protein denaturation associated to treatment with the organic solvent. In conclusion, this paper should be considered as basis for further studies concerned with the potential application of soy-whey and tofu-whey proteins as emulsifiers in different systems.

Open access

Marijana Simić, Slađana Žilić, Olivera Šimuruna, Bojana Filipčev, Dubravka Škrobot and Jelena Vančetović

Abstract

In this study, the effect of anthocyanin-rich popping maize flour on phenolic profile, antioxidant capacity and color of bread were investigated. Texture and sensory properties of maize mix-breads were evaluated also. Replacing 30% of wheat flour with blue- and dark-red-seeded maize flours increased the content of total phenolic compounds, ferulic and p-coumaric acids of mix-breads compared to the control bread. In addition, anthocyanins from maize flours improved functional profile of breads. Despite thermal degradation, the content of anthocyanins in crumb of blue and dark-red maize mix-breads was high and amounted to 142.3 mg CGE/kg and 84.4 mg CGE/kg, respectively. In his acylated and non-acylated forms, cyanidin 3-gluco-side was the most prevalent anthocyanins in maize mix-breads. However, given to the synergistic and antagonistic interaction that arises from the co- existence of numerous antioxidant compounds in food, anthocyanin-rich maize flour had no effect on the increase in the bread antioxidant capacity.

Anthocyanin-rich maize flour changed the bread crumb color to a red range. Although maize mix-breads had worse textural properties compared to the wheat bread, their sensory quality was improved.