Czech Journal of Food Sciences
Latest Publications


TOTAL DOCUMENTS

1481
(FIVE YEARS 185)

H-INDEX

37
(FIVE YEARS 4)

Published By Czech Academy Of Agricultural Sciences

1805-9317, 1212-1800

2021 ◽  
Vol 39 (No. 6) ◽  
pp. 479-486
Author(s):  
Garsa Alshehry‏ ◽  
Amro Abdelazez ◽  
Heba Abdelmotaal ◽  
Walid Abdel-Aleem

Beetroot (Beta vulgaris L.) is one of the plants that contain biologically active compounds that have a function in the prevention and treatment of a wide variety of diseases. The study aims to design new cookies that will support certain groups, such as schoolchildren who may be anaemic. Also, to determine four cookie treatments that were planned to substitute white wheat flour with extraction rate of 72% as follows: T<sub>0</sub> (0%), T<sub>1</sub> (2.5%), T<sub>2</sub> (5.0%), T<sub>3</sub> (7.5%), and T<sub>4</sub> (10%) of beetroot powder to replace 100 g of flour; the cookies were baked at 180 °C for 30–35 min. The chemical composition was assessed, included total phenols, flavonoids, and minerals. Furthermore, during a three-week storage period, antioxidant activity and betalain pigments were evaluated, and sensory evaluation and microbiological assessment were done. Sensory evaluation revealed that the replacement ratio of 10% beetroot was acceptable to the cookies manufactured from white wheat flour with extraction rate of 72%. Compared to the control, a slight decrease was found in the total count of bacteria, fungi, and moulds. We recommend baking beetroot-enriched cookies since it enhances the organoleptic and microbiological characteristics.


Author(s):  
Xianghui Kong ◽  
Yinpeng Ma ◽  
Yu Pan ◽  
Wei Jiang ◽  
Dingjin Li ◽  
...  

Assessments of molecular weight distribution and activity/efficacy of Auricularia heimuer polysaccharides (AAP) are of substantial significance for its extraction process optimisation. In the present study, single-factor orthogonal test and response surface methodology were employed to optimise extraction conditions of AAP. Furthermore, a rat hyperlipidaemia model was established to compare the lipid-lowering activity of polysaccharides obtained by three extraction methods. Conditions for enzymatic hydrolysis were optimised as pH 5.0, 1% cellulase, 2.5% substrate concentration and enzymolysis time of 1.5 h, leading to an up to 31.8% polysaccharide yield and 89.13% of polysaccharides within the molecular weight range of 5 000 Da to 10 000 Da. The results of animal experiments showed that the lipid-lowering activity of enzymolysis-extracted polysaccharides was significantly higher than that of water- and ultrasonic-extracted ones (P &lt; 0.01). So the present study revealed that enzymatic hydrolysis-extracted polysaccharides showed the strongest hypolipidaemia activity, providing a basis for the development of A. heimuer-based functional foods and drugs.


Author(s):  
Mónika Bartalné Berceli ◽  
Eszter Izsó ◽  
Szilveszter Gergely ◽  
András Salgó

Three novel bread additives were developed, namely wheat bran (WB), wheat aleurone-rich flour (ARF) fraction and germinated soybean [sprouted soy-based additive (YASO)]. Their applications were tested in bread dough systems. The additives showed different chemical compositions targeting different nutritional effects in bread. In each case, three different concentration ranges were used (WB 10–30%, ARF 10–30%, YASO 10–50%). Rheological differences were sensitively detected by the Mixolab technique in the mixed dough. So the rheological effects caused by compositional changes were reflected by the results of the above-mentioned technique. Based on Mixolab curves, optimal levels of applied additives (WB 14%, ARF 25% and YASO 30%) were defined. These are acceptable from a compositional and rheological point of view as well. The optimised mixtures were tested with the measurements of Rapid Visco Analyser (RVA) in slurry form, and characteristic effects of additives were observed. Based on Mixolab and RVA techniques, valuable rheological 'fingerprints' could be generated. These support the conscious and planned modification of rheological properties of bread products and the application of novel bread additives.


Author(s):  
Young Suk Kim ◽  
Jong Min Lim ◽  
Bon-Hwa Ku ◽  
Hyung-Rae Cho ◽  
Jae-Suk Choi

We aimed to increase the ginsenosides present in fermented red ginseng and enhance cordycepin production by Cordyceps militaris using solid-state fermentation. After 50 days of fermentation, red ginseng solid-state fermented with C. militaris demonstrated considerably higher contents of Rb3 (9.16%), Rd (513.93%), Rg2 (63.12%), Rg3 (20R; 112.53%), and Rg3 (20S; 101.17%) than untreated red ginseng. As the fermentation time increased, the production of cordycepin gradually increased, yielding approximately 34.8 mg kg<sup>–1</sup> of cordycepin after 50 days of fermentation. In conclusion, red ginseng fermented by C. militaris could be used as natural herbal medicine or dietary supplement with several health-beneficial effects.


Author(s):  
Kexin Wang ◽  
Mengdi Huang ◽  
Simin Yang ◽  
Xin Li ◽  
Yumeng Gao ◽  
...  

In this study, 22 mung bean varieties from different producing areas in China were used as materials to provide a theoretical basis for the breeding and utilisation of special mung bean sprout varieties. Principal component analysis and cluster analysis were used to comprehensively evaluate the overall quality. Finally, 22 germinated mung bean varieties were divided into 3 edible quality grades according to their quality scores. The results showed that Lvfeng 2 and Ankang mung bean sprouts with better comprehensive characters were varieties with higher scores, which could be developed and utilised as characteristic mung bean sprouts. The content of protein, total phenol and antioxidant capacity of edible parts of Lvfeng 2 and Ankang mung bean after germination are higher than those of other varieties, so they are suitable for research and development as functional mung bean sprouts.


Author(s):  
Di Chen ◽  
Qiang Cheng ◽  
Xinxin Xia ◽  
ShIhua Chen ◽  
Changqing Shao ◽  
...  

The correlations between water state and the key factors affecting sourdough quality, including cell activity and acidification capacity of lactic acid bacteria (LAB), were established in this study. Results revealed that with the increase of frozen storage time, the cell density (CD), total titratable acidity (TTA), and organic acids content declined, whereas the pH value rose. Further, the freezable water content (FWC) and free water quantity (FWQ) decreased, but the total water loss rate (WLR) and immobilised water quantity (IWQ) increased. The CD showed a highly inversely correlation with WLR, and the pH value was strongly inversely correlated to the FWQ. The confocal laser scanning microscopy (CLSM) observed that the ice crystals had larger volumes during frozen storage. Our data, for the first time, disclosed that the total water content and the FWQ may play a crucial role in maintaining the viability and acidification capacity of LAB in frozen sourdough.


Author(s):  
Kivaandra Dayaa Rao Ramarao ◽  
Zuliana Razali ◽  
Chandran Somasundram

Drying kinetics of Malaysian Moringa oleifera leaves was investigated using a convective-air dryer. The drying parameters were: temperature (40, 50, 60, 70 °C), air velocity (1.3 m s<sup>–1</sup>, 1.7 m s<sup>–1</sup>). The drying process took place in the falling rate period and there was an absence of a constant rate period in this experiment. Six mathematical models (Lewis, Henderson and Pabis, Wang and Singh, Peleg, Page, and logarithmic) were selected for the description of drying characteristics of the leaves. The Wang and Singh model was determined as the best model based on the highest overall coefficient determinant (R<sup>2</sup>) and the lowest overall root mean square error (RMSE). The effective diffusivity (D<sub>eff</sub><sub> </sub>) was also calculated which was in the range of 3.98 × 10<sup>–11</sup> m<sup>2</sup> s<sup>–1</sup> to 1.74 × 10<sup>–10</sup> m<sup>2</sup> s<sup>–1. </sup>An Arrhenius relation was constructed to determine the activation energy for the samples in the convective air dryer. The activation energy for M. oleifera leaves was 39.82 kJ mol<sup>–1</sup> and 33.13 kJ mol<sup>–1</sup> at drying velocities of 1.3 m s<sup>–1</sup> and 1.7 m s<sup>–1</sup>, respectively.


Author(s):  
Eid Brima ◽  
Hatem Mohamed

The aim of this study was to evaluate the distribution of essential and toxic elements between the orange juice and orange flesh of various orange cultivars. Different orange cultivars, such as Abousorah [Citrus sinensis (L.)], Aseear (Citrus aurantium), Afandi (Citrus reticulata Blanco), Helo (Citrus sinensis), and grapefruit (Citrus paradisi), were collected from local markets. Elemental analysis was carried out after microwave-assisted digestion using inductively coupled plasma mass spectrometry (ICP-MS) in 18 samples. Eleven elements (V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd, and Pb) were analysed. Their average concentrations ranged from 0.006 µg g<sup>–1</sup> to 7.13 µg g<sup>–1</sup> in both orange juice and flesh (wet weight). There was a high increase in the average concentrations of all elements in the juice compared to the flesh of up to 40-fold.


2021 ◽  
Vol 39 (No. 5) ◽  
pp. 360-367
Author(s):  
Achmat Sarifudin ◽  
Enny Sholichah ◽  
Woro Setiaboma ◽  
Nok Afifah ◽  
Dewi Desnilasari ◽  
...  

Native cassava flour can be modified to be instant flour by heating the cassava flour in ethanol solution. The impact of heating temperatures of 60, 80, and 100 °C (coded as ICF-60, ICF-80, and ICF-100) on the properties of instant cassava flour (ICF), including colour, morphological, and thermal properties, water absorption, and solubility indexes and pasting behaviour, were investigated. Results showed that ICF produced at higher temperatures exhibited lower lightness, higher redness, and yellowness values. ICF-60 and ICF-80 still displayed the granular forms and birefringence properties of native starches, while granules of ICF-100 were broken and partially lost their birefringence properties. Results of X-ray diffraction (XRD) technique and differential scanning calorimetry (DSC) analysis suggested that the amylopectin double helixes of crystalline regions within the structure of ICF orientated to more perfect conformation before they were disrupted at the highest heating temperature (100 °C). During hydration, the starch granules of ICF-60 and ICF-80 absorbed water into their granules; meanwhile, ICF-100 entrapped water within the matrix formed by the entanglements of ICF-100 particles. Results of pasting behaviour analysis indicated that ICF-60 and ICF-80 showed better thermal stability while ICF-100 exhibited the highest cold viscosity.


2021 ◽  
Vol 39 (No. 5) ◽  
pp. 410-417
Author(s):  
Eliška Čermáková ◽  
Kamila Zdeňková ◽  
Kateřina Demnerová ◽  
Jaroslava Ovesná

The success of polymerase chain reaction (PCR) assay depends on template deoxyribonucleic acid (DNA) being sufficient with respect to both quantity and quality. Some biological materials contain compounds which inhibit the functioning of DNA polymerase and thus need to be removed as part of the DNA extraction procedure. The aim of the present experiments was to optimise the process of DNA isolation from various types of black, fruit and herbal teas. A comparison was made between two cetyltrimethylammonium bromide (CTAB)-based protocols and two commercially available DNA purification kits. The yield and integrity of the extracted DNA were monitored both spectrophotometrically and using agarose gel electrophoresis. The presence/absence of inhibitors in the DNA preparations was checked by running quantitative real-time PCRs. The optimal protocol was deemed to be the CTAB method described in ISO 21571:2005, so this method is recommended for the routine sample analysis of tea products.


Sign in / Sign up

Export Citation Format

Share Document