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Millet (Panicum miliaceum L.) is more resistant to climatic and soil conditions but the yields are lower than in wheat (Triticum aestivum L.), therefore its cultivation was given up for decades in Hungary. Millet is a suitable raw material for the production of pasta products without using eggs and it has other advantageous physiological effects, therefore its cultivation in Hungary is expected again. Millet is a gluten free cereal so it is not able to create viscoelastic protein network. During the biochemical studies the activity of enzymes (peroxidase, polyphenol oxidase) influencing the colour of the flour, flour mixtures (T. aestivum L., Triticum durum L., P. miliaceum L.), and pasta products were examined. Oxidoreductases in wheat flour have always been of interest to cereal chemists. The effects of peroxidase (EC 1.11.1.7) (POX) are much less thoroughly documented, although they are reported to have a relatively high level of activity in different flours. These days there are also insufficient research data on how the millet in dry pasta modifies the enzyme activity and the storage stability and shelf life of dry pasta products.

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The changes in the activity of enzyme polyphenol oxidase, the concentration of total soluble phenolic compounds and soluble protein content in different tobacco cultivars (Virginia and Burley) during cultivation, then in a combined curing model system were studied. The latter was a special combination of air-curing and flue-curing methods followed by a long fermentation period to optimize the treatment of tobacco plants used both as protein sources and starting materials in tobacco industry. The results suggest that a cultivation period of 13–14 weeks could be better for tobacco plants as protein sources, however, for starting materials for industrial use 16–17 weeks are optimal. It was found a four-week curing period could be the best for two tobacco cultivars (Virginia and Burley) in the case of using them both as protein sources and starting materials in tobacco industry.

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Millet has attracted a great deal of interest due to its valuable agricultural, nutritional, and functional properties. In this study the aim was the investigation of millet usability in dry pasta products. Chemical, enzymological, and sensory parameters were measured and monitored in Triticum aestivum, Triticum durum, and millet containing pasta products during a 12-month-long storage period. According to our results, during the storage, millet had a strong effect on different parameters: because of increased acid value, the shelf life was reduced, and millet significantly influenced the pH value and the water soluble polyphenol content. The highest scores were measured in T. durum and T. durum-millet pasta samples in the sensory test, while the T. aestivum-millet mixture pasta got the lowest scores. Also in our experiment we tested how the drying temperature modifies polyphenol oxidase enzyme (PPO) activity right after drying and during storage. The samples containing millet flour had higher PPO activity in all cases after drying, while pasta made with T. durum had the lowest PPO activity. Our results showed that drying temperature has a significant impact on PPO activity.

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Increasing the protein and antioxidant content of food products is a constant challenge amongst researchers. Dried pasta products are popular amongst all groups of society. The most important factor in pasta processing is the quality of the flour. Millet (Panicum miliaceum) flour has high nutritional value, enriching it with cricket (Gryllus bimaculatus) flour is good choice to increase the quality of protein composition and antioxidant properties of products. Flour mixtures of millet and insect flours (5% and 10%) were analysed after mixing and pasta processing. Addition of wheat gluten improved both texture and nutrition value of pasta products. Total polyphenol content, antioxidant capacity, total protein content, free and total amino acid composition were studied. Quality analysis of dried pasta products were carried out according to Hungarian standards. Data was analysed with Kruskal-Wallis test, Dunn's pair-wise post hoc test was used with Bonferroni correction. The correlation was determined by Spearman's rank. Addition of cricket flour modified the pH, acid value, moisture content, and colour of the samples, these changes lasted during storage. Enrichment could increase the total phenol content significantly even at the low level of 10%. Heat treatment during pasta processing had negative effect on the antioxidant capacity except at higher cricket flour contents. Cricket flour's high protein content proportionately increased millet flour's, thus pasta products'. Dried pasta products passed all quality norms. Enrichment of millet flour with cricket flour is favourable from both nutritional and quality aspects.

Open access
Acta Alimentaria
Authors:
M. Mardani
,
L. Somogyi
,
I. Szedljak
,
I. Prauda
,
J. Farmani
, and
K. Badakné Kerti

Abstract

Sea buckthorn (Hippophae rhamnoides) with high antioxidant capacity is distributed all over the world, but has never been used as a natural antioxidant in oils to replace synthetic antioxidants. Therefore, this study was performed to investigate the effectiveness of sea buckthorn extract in comparison to a common natural antioxidant rosemary extract and a synthetic antioxidant on retarding lipid oxidation. First the extracts were characterised, and it was found that sea buckthorn extract had higher polyphenol contents, radical scavenging activity, and higher antioxidant capacity. Then the proper concentrations for the use of these antioxidants were determined. Additionally, the progress of lipid oxidation during cycles of frying was assessed in terms of free fatty acids content, peroxide value, p-anisidine value, TOTOX value, colour, total polar compounds, and Induction period. The general order of effectiveness for inhibition of high oleic sunflower oil degradation during frying was: sea buckthorn > BHT > rosemary > control (P <0.05).

Open access