The effect of processing temperature on microbial safety and antioxidant activity of minimally processed "raw food"

The assessment of the effect of dehydration temperatures (40 °C, 50 °C, and 60 °C) on the microbiological quality, antioxidant activity and oxidative stability of lipids of buckwheat-based minimally processed "raw food" (MPRF) was performed. Buckwheat flakes with various ingredients were soaked in sterile distilled water for 20 h, then MPRF samples were formed and dehydrated at constant temperature. Total viable counts, coliform, fungi, yeasts and aerobic spore-forming bacteria counts were evaluated in dehydrated products. While fungi were effectively reduced at all drying temperatures, higher total viable and coliform counts were found in MPRF samples after drying at 40 °C and 50 °C. Generally, antioxidant activity of MPRF samples did not significantly differ, and superoxide dismutase activity remained constant with the increase of drying temperature. The inhibition of lipid peroxidation was significantly higher in MPRF samples dehydrated at 40 °C than in those dehydrated at higher temperatures. Lipid oxidation stability measured by peroxide value, conjugated dienes content and thiobarbituric acid-reactive substances assay was not substantially affected during the dehydration process. Preparing MPRF by dehydration at 40 °C and 50 °C was considered as representing a microbial hazard whereas overall antioxidant activity was found to be minimally influenced by the dehydration temperatures. © 2016 National Agricultural and Food Centre (Slovakia).University of Pardubice, Pardubice, Czech Republic [SGS_2016_001

Tin compounds in food-their distribution and determination

The aim of this work was optimization of the methods of trace-and ultratrace analysis, such as ICP-OES, ETA-AAS for charting the resources of individual forms of tin in foodstuffs. Increase of the sensitivity of the method of ICP-OES was achieved using the techniques of generation of hydrides, which was also optimized. Based on the information available on the occurrence of the different forms of tin, it appears that many of these organometallic compounds are contained in marine animals; attention has mainly focused on organisms such as marine fish, crustaceans, molluscs and algae. Tin compounds of predominantly inorganic origin can be found in foods and beverages which are packed in cans with a protective tin coating, too. The above mentioned methods have been applied to the analysis of selected beverages with low content of tin such as Coca Cola, Sprite, Fanta, Gambrinus 10°, PowerKing, and milk in the cans. Furthermore samples of animal origin as Sardines in oil, and Hunter's salami were examined, too. Prior to the determination of tin, samples need to be appropriately modified or analysed. Decomposition of the samples was done in the microwave system. Low pressure ion exchange chromatography with on-line detection of ICP-OES was used for separation of inorganic tin compounds. Separation of organically bound tin compounds was performed by HPLC on a column of ACE C-18, 3 µm, 15 cm x 1.0 mm with off-line detection by ETA-AAS. All of the above forms of tin compounds can be separated with this column. Due to the improvement in the detection of organically bounded tin, HPLC with identical ACE C-18 column coupled online for example with ICP-MS or spectrofluorimetry could be recommended. © 2019 Muhammad Arba et al

Antioxidant properties of processed cheese spread after freeze-dried and oven-dried grape skin powder addition

Processed cheese spread (PCS) is a popular product with high nutritional value and containing protein, fat and minerals. Grape skin is waste from winery processing plants that still has phenolic substances with significant antioxidant activity that could be used for valorisation of processed cheese and increasing the content of nutrients, phenolics and overall antioxidant properties. Both oven-dried (OD) and freeze-dried (FD) grape skin (GS) powder was characterised by the principal ingredients, the content of phenolic compounds and antioxidant capacity. Similarly, the influence of the addition of OD-GS and FD-GS powders on processed cheese spread (PCS) at 1% and 2% (w/w) levels were examined. The OD-GS and FD-GS powders were characterised by protein content, fat content, moisture and dietary fibre, thus showing that drying technique did not affect those parameters. The OD-GS powder exhibited higher content of rutin, (+)-catechin, (-)- epicatechin and total flavonoid content (TFC), while higher total phenolic content (TPC) and ABTS radical cation were observed for freeze-dried GS powder. Fortification of PCS with 1% and 2% (w/w) of GS powder increased protein content. An ANOVA procedure revealed that addition of FD-GS powder to processed cheese spread was superior to TPC values together with rutin, (+)-catechin, and (-)-epicatechin contents. The higher phenolic contents reflected the higher antioxidant capacity of PCS samples fortified with FD-GS powder. Freeze-dried grape skin powder was the better choice for valorisation of processed cheese spread. © 2020 Potravinarstvo Slovak Journal of Food Sciences, Licence

Effects of the lactation period, breed and feed on amino acids profile of mare's milk

The effects of the lactation period, breed, and feed on amino acids profile of mare's milk were investigated. The feed contained two major essential amino acids (EAAs) leucine (7.31-10.3 g. kg-1) and arginine (6.37-9.59 g. kg-1); it also included minor EAAs methionine (2.11-3.05 g. kg-1) and histidine (2.48-3.60 g. kg-1). Glu+Gln, Asp+Asn, and proline, major nonessential amino acids (NEAAs), constituted approximately 60% of total NEAAs (TNEAAs). The ratio of total EAAs to NEAAs ranged from 1:1.2 to 1:1.4. Amino acids (AA) content throughout all milk samples varied due to mare's different conditions and lactation days. Except for the 1P milk sample, total AA content in the 2-8Ps specimens caused by differences in breed oscillated from the 2nd to 28th day of lactation within the following limits: 21.9-54.6 g. kg-1, 33.6-70.7 g. kg-1, 38.1-71.2 g. kg-1, 29.46-74.2 g. kg-1, 52.2-87.1 g. kg-1, 37.9-70.3 g. kg-1 and 26.4-64.5 g. kg-1, respectively. In relation to TEAAs in milk, the highest EAAs levels were reached in arginine, leucine and lysine ranging between 2.41-4.35 g. kg-1, 3.36-5.59 g. kg-1 and 2.72-4.80 g. kg-1, respectively, while the lowest AAs amounts were indicated in histidine and methionine, 0.91-1.58 g. kg-1 and 1.23-2.04 g. kg-1 respectively. Total NEAAs content was slightly higher than that of EAAs; the TNEAAs to TEAAs ratio was 1:0.9 proximately. Glu+Gln, Asp+Asn and proline were determined as major NEAAs of milk ranging between, 6.77-11.0 g. kg-1, 3.21-5.60 g. kg-1 and 1.25-2.18 g. kg-1, respectively; levels of NEAAs such as cysteine and glycine oscillated between 0.89-1.52 g. kg-1 and 0.64-1.15 g. kg-1, respectively. The average TAAs contents caused by breed differences were 62.8 g. kg-1, 42.8 g. kg-1, 44.7 g. kg-1 and 44.8 g. kg-1, respectively, on the 2nd, 5th, 10th, and 28th lactation days. © 2020 Potravinarstvo Slovak Journal of Food Sciences

Reduce the sulphur dioxide content of wine by biological process in relation to the content of polyphenolic substances

In recent years, many papers have paid attention to the bioactive compounds, particularly to the antioxidant activity of polyphenolic compounds in food and beverages, due to their positive effect on human body. Therefore, the phenolic compounds and their antioxidant capacity become an important quality parameter, especially in niche markets concerned with health benefits. Wine is an excellent source of various classes of polyphenols. The phenolic compounds are responsible for the sensory characteristics, particularly colour, astringency, bitterness, and aroma, too. Another very important ingredient in the wine is added the sulphur dioxide, which has the role to protect these reductive components of wines. Sulphur dioxide has the effects of antioxidant, antimicrobial and preservative that is mutually merging. However, it is possible to increase the stability of the complex of biologically active substances (BAS), as holders of natural antioxidant capacity. The present contribution brings opportunities rather than full elimination, but a substantial reduction of the content of sulphur dioxide, which protects the wine during the entire technological process of manufacture and treatment. The dosage of sulphur dioxide can be reduced in its values from 15 to 40% of the total health of the authorized maximum sulphur dioxide content of wine.operational Program called Research and Development for Innovations (Vyzkum a vyvoj pro inovace); state budget of the Czech Republic within the Centre of Polymer Systems Project [CZ.1.05/2.1.00/03.0111]; Brno University of Technology - MSMT CR [22738]; European Fund for Regional Development (ERDF)European Commissio

SONDEO ARQUEOLÓGICO SECTOR 35 [Material gráfico]

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 201

SONDEO ARQUEOLÓGICO CIERRE SUR CORTE 0 [Material gráfico]

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 201

Interaction of polyphenols and wine antioxidants with its sulfur dioxide preservative

Wine is considered to be a significant alcoholic beverage, which is the result of fermentation of grape must or mash. Wine is a must when the substances contained in it play a major role, which are essential inhibiting water, carbohydrates, acids, minerals, nitrates, polyphenols and aromatics. These biochemical components are an important tracking element in wine evaluation in terms of chemical analyzes. An important parameter of monitoring is polyphenolic substances. Polyphenol substances are identified in plant materials as several thousand pieces with a very diverse structure. However, they have a common feature up to one or more aromatic rings substituted with hydroxyl groups. These substances may be present in plant material in a small or large amount. The total daily intake of polyphenols is estimated at 1 g. This is a higher intake than antioxidant vitamin intakes and it is confirmed that their antioxidant activity is higher than that of antioxidant vitamins. When monitoring the content of all polyphenols (TPC) in selected samples using a spectrophotometric method, a higher TPC content of red wines against white white wines can be observed. Total antioxidant activity is introduced to compare antioxidant effects of different mixtures and is based on the ability to eliminate radicals. Antioxidant activity and effects of polyphenols can be inhibited by the addition of preservatives to wine. The preservative is sulfur dioxide (SO2), which has antimicrobial and antioxidant effects. This compound is not harmless because it is a strong allergen, blocks bacteria in the digestive tract and prevents the conversion of sugars and alcohol derivatives in the liver by blocking vitamin B. In the normal life, SO2 is consumed under the E 220 mark. The aim of this work is to monitor the change in the total polyphenols content related to free and bound sulfur dioxide (SO2) content using accredited OIV-MA-AS323-O4B: R, 2009 samples in wine samples. Comparison of organic wines and wines produced by classical, it was found that organic wine have a higher content of biologically active substances and have a strong correlation factor TAA - total SO2 (r = 0.77 to 0.91), depending on the wine variety. © 2018 Potravinarstvo Slovak Journal of Food Sciences

The Effect of Drying Temperature on Carotenoids and Anthocyanins: Meta-analysis of Data

Cílem této studie bylo ohodnotit efekt sušící teploty na obsah karotenoidních látek a antokyanů v ovoci a zelenině s využitím meta-analýzy dat. Response ratio (RR) byl použit jako metrika pro kvantitativní stanovení, zda je sušení při teplotě 40°C lepší než při vyšších teplotách s ohledem na obsah karotenoidů a antokyanů. Pro meta-analýzu bylo použito 14 publikací popisující efekt sušení na karotenoidní látky a 8 popisující vliv sušící teploty na antokyany. Pro produkty sušené při 70°C indikovala hodnota RR významný pokles obsahu karotenoidů (RR=0,71) a antokyanů (RR=0,77) pro produkty sušené při 80°C. Analýza jednoznačně neprokázala, že sušení při 40°C přineslo je výhodné s ohledem na retenci karotenoidů a antokyanů ve srovnání s obsahem látek v produktech sušených při vyšších teplotách (50°C, 60°C, 70°C and 80°C).The aim of this study was to review studies that evaluated the effect of drying temperature on the carotenoid and anthocyanin contents in fruits and vegetables using meta-analysis. Response ratio (RR) as a meta-analytical metric was used to quantify whether drying at 40°C is better than at higher temperatures with respect to the carotenoid and anthocyanin contents. The database search revealed 14 and 8 scientific papers describing the effect of drying temperatures on the content of carotenoids and anthocynanins, respectively. Significant decrease of carotenoid content was observed in products dried at 70°C (RR=0,71) and RR=0,77 (p=0,008) was calculated for anthocyanin content followed by drying at 80°C. In general, the results of meta-analysis did not confirm that drying at 40°C is beneficial in comparison with those dried at 50°C, 60°C, 70°C and 80°C