8 research outputs found
Influence of selected factors on the content and properties of starch in the grain of non-food wheat
Three non-food cultivars of winter wheat (Biscay, Clarus, Rapsodia) were grown at four locations in the Czech Republic with different agro-ecological conditions in the years 2005-2008 and two levels of nitrogen fertilization 90 and 120 kg N/ha were used. The influence of growing conditions (year, location, cultivation technology) on grain yield, starch content, protein, gluten, share of amylose in starch, falling number and amylographic characteristics. All qualitative indicators were significantly affected by the weather. Wheat grown in the areas 500 m a.s.l. had lower grain yield of 2.8 t/ha (8.4 t/ha), higher starch content of 2.1% (69.0%) and lower content of proteins by 1.8% (10.2%) in grain than wheat grown in the fertile conditions (below 300 m a.s.l.). The cv. Biscay had the highest starch content of 68%; the proportion of amylose in the starch was in the range 22-27%. The content of proteins was negatively correlated with starch content (r = -0.89). The level of damage of starch a-amylase was most affected by wet weather during ripening falling number was 62 s, with a very low amylographic gelatinization maximum (30-155 Brabender units) and a low gelatinization temperature at the maximum (67-74 degrees C). The respective values recorded in dry conditions were ca 300 s, AU 600 and 90 degrees C. Most damaged starch was recorded in the cv. Clarus.Ministry of Agriculture of the Czech Republic [1G57056, RO0414
Unusual aspects of the fat content of mealworm larvae as a novel food
The work focuses on some aspects of content and properties of the fat in mealworm as a novel food. The total fat content of this species is a markedly variable nutritional value that is significantly dependent on the breeding conditions. In this work, the fat content of a mealworm from various Czech suppliers ranged from 202 g.kg -1 to 282 g.kg -1 dry matter, determined using the Soxhlet extraction method. The total average value from all suppliers was 235.8 ±40.8 g.kg -1 . This is a range that can be expected by the customer when buying mealworm larvae from a random Czech supplier. Furthermore, the work graphically compares the values of the total fat content with other comparable commodities of animal origin, e.g. chicken or fish. Finally, the aim was to obtain initial information about the comparison of the sensory properties of the mealworm fat with other fats of animal origin using a simple electronic nose. There was a difference between the fat obtained from insect larvae and the conventional unprocessed fats. This work brings a wider view of fat as a taste carrier in a new food - a mealworm. © 2019 Potravinarstvo Slovak Journal of Food Sciences
Is edible insect as a novel food digestible?
This work deals with the digestibility of a selected species of edible insect - mealworm (larvae) as novel food in dependency on its culinary treatment. The aim of this work was to find suitable thermic culinary treatment of mealworm larvae considering its optimum digestibility by human. The digestibility of materials from whole insect and extracted nitrogenous substances was determined using three different culinary treatments - without culinary treatment (freshly killed), dried insect and roasted insect. The digestibility was determined by gravimetric in vitro method using pepsin and pancreatin enzymes and their combination. The total nitrogen content of the insect samples was determined by the Kjeldahl method. The digestibility of the whole homogenized larvae using the combination of pepsin and pancreatin enzymes, thus simulating human digestion in-vitro, ranged from 81% for roasted specimens to 91.5% for culinary unprocessed insect. Similarly, the digestibility of nitrogenous substances of homogenized insect samples using this combination of enzymes ranged from 24.2% for roasted specimens to 80.2% for culinary unprocessed samples. The work showed the dependence of the digestibility of the mealworm larvae on the culinary treatment - the increasing heat load of the sample reduced the digestibility. Furthermore, it proved the effect of the digestive enzyme on the digestibility of the insect sample. © 2019 Potravinarstvo Slovak Journal of Food Sciences
Sensor systems for detecting dough properties fortified with grape pomace and mealworm powders
The present article dealt with the fortification of plain wheat flour by the addition of grape pomace flour and mealworm larvae powder, focusing on the mineral content and selected properties of the dough. The work also analyzed the properties of one mixture in a weight combination of 80% wheat flour, 10% grape pomace, and 10% mealworm. X-ray analysis was used to measure the mineral content of calcium, iron, copper, and zinc. The properties of the individual mixture were monitored using an experimental electronic nose and a thermodynamic sensor system during the leavening. The results showed that a combination of 50% grape pomace and 50% mealworm larvae was advantageous from the viewpoint of the favorable representation of minerals. The analyzed mixture contained a high proportion of calcium (3976.7 ± 362.9 mg·kg−1), iron (209.3 ± 25.7 mg·kg−1), and copper (65.0 ± 100.1 mg·kg−1) for grape pomace as well as a high proportion of zinc (277.0 ± 21.9 mg·kg−1) for the mealworm larvae. However, this mixture showed a small change in the heat flux response when analyzed with thermodynamic sensors (lower yeast activity and worse gas formation properties resulted from the sensor characteristic with a lower response). The 100% wheat flour had the highest response, and the second highest response was recorded for a mixture of wheat flour with 10% grape pomace and 10% mealworm larvae. This combination also often had one of the highest responses when measured with an experimental electronic nose, so this combination was considered as one of the most advantageous options for processing from the mixtures mentioned in the article. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.TBU in Zlin [IGA/FT/2020/010]; project BUT in Brno [FEKT-S-20-6215
Baking quality of wheat-rye mixtures
The most important chemical compounds for wheat dough are gluten proteins -gliadins and glutenins which have the distinctive rheological ability to form a dough matrix that determines bread quality. Other cereal flours as rye flour do not have these unique properties, but they can improve nutritional aspects of daily consumed breads such as higher intake of fibre which has a positive effect on digestion and decreases risk of hypercholesterolemia, obesity and heart disease, and current trend in bakery is to replace part of wheat flour with rye flour. In this work 11 ratios of wheat-rye mixtures were prepared; flour quality (Zeleny sedimentation volume, Hagberg falling number, water absorption), machine workability of dough and consequently bread quality characteristics (bread shape, mean bread volume, dough yield, pastry yield, baking loss, texture parameters, image analysis) were investigated. The results showed that parameters of final product are significantly affected by wheat-rye ratio and flour quality. Moreover the addition of rye flour does not influence machine workability of the mixtures
Avenanthramides: Unique Bioactive Substances of Oat Grain in the Context of Cultivar, Cropping System, Weather Conditions and Other Grain Parameters
Our study was focused on the evaluation of the content of a wider spectrum of eight avenanthramides (AVNs) as unique components of oat grain under the effects of four selected factors (cultivar, locality, cropping system, and year). The weather effects on changes in the AVN content and their relationship to other important parameters of oat grain were further evaluated in more detail. A sensitive UHPLC system coupled with a QExactive Orbitrap mass spectrometer was used for AVN quantification. AVNs confirmed a high variability (RDS = 72.7–113.5%), which was dominantly influenced by the locality and year factors. While most AVN types confirmed mutually high correlations (r = 0.7–0.9), their correlations with the other 10 grain parameters were lower (r ≤ 0.48). Their significant correlations (0.27–0.46) with β-D-glucan could be used in perspective in breeding programs for the synergetic increase of both parameters. PCA analysis and Spearman correlations based on individual cultivars confirmed a significant effect of June and July precipitation on the increase of Σ AVNs. However, the results also indicated that higher precipitation can generate favorable conditions for related factors, such as preharvest sprouting evoking a direct increase of AVNs synthesis in oat grain
Avenanthramides: Unique Bioactive Substances of Oat Grain in the Context of Cultivar, Cropping System, Weather Conditions and Other Grain Parameters
Our study was focused on the evaluation of the content of a wider spectrum of eight avenanthramides (AVNs) as unique components of oat grain under the effects of four selected factors (cultivar, locality, cropping system, and year). The weather effects on changes in the AVN content and their relationship to other important parameters of oat grain were further evaluated in more detail. A sensitive UHPLC system coupled with a QExactive Orbitrap mass spectrometer was used for AVN quantification. AVNs confirmed a high variability (RDS = 72.7–113.5%), which was dominantly influenced by the locality and year factors. While most AVN types confirmed mutually high correlations (r = 0.7–0.9), their correlations with the other 10 grain parameters were lower (r ≤ 0.48). Their significant correlations (0.27–0.46) with β-D-glucan could be used in perspective in breeding programs for the synergetic increase of both parameters. PCA analysis and Spearman correlations based on individual cultivars confirmed a significant effect of June and July precipitation on the increase of Σ AVNs. However, the results also indicated that higher precipitation can generate favorable conditions for related factors, such as preharvest sprouting evoking a direct increase of AVNs synthesis in oat grain
Senzorové systémy pro detekci vlastností těsta obohacené o prášky z hroznových výlisků a mouček z červů
The present article dealt with the fortification of plain wheat flour by the addition of grape pomace flour and mealworm larvae powder, focusing on the mineral content and selected properties of the dough. The work also analyzed the properties of one mixture in a weight combination of 80% wheat flour, 10% grape pomace, and 10% mealworm. X-ray analysis was used to measure the mineral content of calcium, iron, copper, and zinc. The properties of the individual mixture were monitored using an experimental electronic nose and a thermodynamic sensor system during the leavening. The results showed that a combination of 50% grape pomace and 50% mealworm larvae was advantageous from the viewpoint of the favorable representation of minerals. The analyzed mixture contained a high proportion of calcium (3976.7 +/- 362.9 mg center dot kg(-1)), iron (209.3 +/- 25.7 mg center dot kg(-1)), and copper (65.0 +/- 100.1 mg center dot kg(-1)) for grape pomace as well as a high proportion of zinc (277.0 +/- 21.9 mg center dot kg(-1)) for the mealworm larvae. However, this mixture showed a small change in the heat flux response when analyzed with thermodynamic sensors (lower yeast activity and worse gas formation properties resulted from the sensor characteristic with a lower response). The 100% wheat flour had the highest response, and the second highest response was recorded for a mixture of wheat flour with 10% grape pomace and 10% mealworm larvae. This combination also often had one of the highest responses when measured with an experimental electronic nose, so this combination was considered as one of the most advantageous options for processing from the mixtures mentioned in the article.Tento článek se zabýval obohacením hladké pšeničné mouky přidáním mouky z hroznových výlisků a prášku z larev moučných červů, se zaměřením na obsah minerálů a vybrané vlastnosti těsta. Práce také analyzovala vlastnosti jedné směsi v hmotnostní kombinaci 80% pšeničné mouky, 10% hroznových výlisků a 10% moučného červu. K měření obsahu minerálů vápníku, železa, mědi a zinku byla použita rentgenová analýza. Vlastnosti jednotlivé směsi byly během kynutí sledovány pomocí experimentálního elektronického nosu a termodynamického senzorového systému. Výsledky ukázaly, že kombinace 50% hroznových výlisků a 50% larev moučných červů byla výhodná z hlediska příznivého zastoupení minerálů. Analyzovaná směs obsahovala vysoký podíl vápníku (3976,7 +/- 362,9 mg střední tečky kg (-1)), železa (209,3 +/- 25,7 mg střední tečky kg (-1)) a mědi (65,0 +/- 100,1) mg středové tečky kg (-1)) pro hroznové výlisky a také vysoký podíl zinku (277,0 +/- 21,9 mg středové tečky kg (-1)) pro larvy moučné červy. Tato směs však při analýze termodynamickými senzory vykazovala malou změnu v odezvě na tepelný tok (nižší aktivita kvasinek a horší vlastnosti tvorby plynu byly výsledkem charakteristiky senzoru s nižší odezvou). 100% pšeničná mouka měla nejvyšší odezvu a druhá nejvyšší odezva byla zaznamenána u směsi pšeničné mouky s 10% hroznových výlisků a 10% larvami moučných červů. Tato kombinace také často měla jednu z nejvyšších odpovědí při měření experimentálním elektronickým nosem, takže tato kombinace byla považována za jednu z nejvýhodnějších možností zpracování ze směsí uvedených v článku. (automatický překlad