Effect of Cold Brew Coffee Storage in Industrial Production on the Physical-Chemical Characteristics of Final Product.

The purpose of this article is to present information about changes in physical properties (pH, TA, and color) and chemical components with bioactive activity in cold brew coffee beverages, during storage before and after HTST processing. Coffee samples were tested using industrial technology (12,000 bottles per batch). The antioxidant activity of the samples was analyzed using ABTS and FRAP methods, the concentration of polyphenols was determined using the UPLC-MS chromatography coupled with mass spectrometry method, and microbiological tests were performed according to PN-ISO/PN-EN ISO standards. The pH value decreased during coffee storage, and the color changed significantly in brightness. Polyphenol concentrations were calculated in the range of 1800 to almost 3400 mg/L, and the antioxidant capacity for ABTS and FRAP reached the ranges of the results successively: 123-195 µMol/100 mL and 158-212 µMol/100 mL. It was observed that HTST pasteurization has a beneficial effect on preserving the beverage in microbiological terms. Also, a positive effect of the process on the release of chemical components responsible for bioactive properties from the beverage was observed, followed by a reduction in antioxidant activity during the first 90 days of storage and between 180 and 270 days during storage.

Comparison of the Chemical Composition of Selected Varieties of Elderberry with Wild Growing Elderberry.

Elderberries of wild-growing shrubs are most often used; however, various cultivated varieties of this shrub appear more and more often. The aim of this research was to compare the fruit composition of specific varieties with those grown wild in urban and ecologically clean conditions. Six varieties of elderberry grown on one experimental farm and two wild-growing samples from the city center and the landscape park were assessed. The content of vitamin C, antioxidant activity, sugar and organic acid content, triterpenes and carotenoids was marked in the tested fruits. The analyses show that there were significant differences in the content of the tested ingredients between the varieties tested, while the place of cultivation was of less importance. Apart from organic acids and triterpenes, fruits from wild-growing shrubs were more abundant in other compounds determined. The white variety of 'Albida' turned out to be the poorest in bioactive compounds.

Assessing weaning stress - Relations between enamel hypoplasia, δ18O and δ13C values in human teeth obtained from early modern cemeteries in Wroclaw, Poland.

OBJECTIVES: The aim of this paper is to assess linear enamel hypoplasia (LEH) on canines of adults from early modern Wroclaw cemeteries to compare δ13C and δ18O values in enamel formed before, during and after LEH formation, and to attempt to find a link between the selected indicators of the weaning process. MATERIAL AND METHODS: 15 permanent canines with visible LEH were selected for analysis. Age at LEH formation was estimated using the Reid and Dean method. The perikymata count was used to estimate the duration of LEH formation. Incremental stable oxygen and carbon isotopes analysis was performed on tooth enamel to infer stress related to weaning and dietary patterns. Kruskal-Wallis ANOVA, Mann-Whitney U test and Spearman correlation were used in statistical inference. RESULTS: The average age of LEH formation was 3.14 years, with an average duration of 111 days. Stable carbon isotope values consistently increase in 73% of the individuals sampled. The values of δ18O do not show a dominant pattern. The average value of δ13C increases over the time of enamel formation. The δ13C values collected below LEH were negatively correlated with δ18O values and the duration of LEH termination. CONCLUSIONS: Marking of carbon and oxygen isotopes indicates different stages of weaning. Advancements in diet change (determined by higher δ13C) corresponds with faster recovery after physiological stress episode. There is no evidence for different breastfeeding models between distinct parishes in early modern Wroclaw.

Effect of Vacuum Impregnation with Apple-Pear Juice on Content of Bioactive Compounds and Antioxidant Activity of Dried Chokeberry Fruit.

Food technology seeks ways to preserve products while maintaining high bioactive properties. Therefore, an attempt was made to assess the effect of the process of impregnation with apple-pear juice and the drying process on the content of bioactive compounds in chokeberry fruit. Chokeberry fruits were subjected to impregnation with apple-pear juice at three levels of vacuum pressure, 4, 6, and 8 kPa; then, they were dried using microwave-vacuum technology. The water activity of the obtained products, the content of fructose, glucose, sorbitol, and polyphenolic compounds, and antioxidant activity were determined. A total of 20 polyphenolic compounds were identified in the fruits and the obtained products (seven anthocyanins, six flavonols, four phenolic acids, and three flavan-3-ols). Preliminary processing, which consisted of introducing the juice ingredients into tissue of the chokeberry fruit, resulted in increased content of bioactive compounds. Moreover, a positive effect of impregnation on the antioxidant stability of the fruit after drying was noted. Water activity in the obtained products showed their microbiological safety. Impregnation at 4 kPa vacuum pressure proved to be the most desirable; in such conditions, the best product in terms of the content of bioactive compounds was obtained.

Effect of pulsed electric field treatment on shelf life and nutritional value of apple juice.

The aim of this study was to assess shelf life and nutritional value of apple juice, including the content of bioactive compounds, after pulsed electric field (PEF) treatment, taking into account different number of cycles: 4, 6, 8 (total 200, 300, and 400 pulses, respectively). Determination of vitamin C and polyphenols concentration, antioxidant activity as well as microbiological analysis were conducted immediately after PEF process and after 24, 48 and 72 h of storage. The results showed that PEF did not affect the content of bioactive compounds. PEF-treated juice did not show changes in the amount of vitamin C and total polyphenols during the storage for 72 h under refrigeration. PEF treatment was effective method for inactivation of a wide range of most common food spoilage microorganisms. PEF process can be used as an effective method of food preservation, allowing prolongation of shelf life and protection of nutritional value. This brings new opportunities for obtaining safe, healthy and nutritious food.

Rheological, Chemical and Physical Characteristics of Golden Berry (Physalis peruviana L.) after Convective and Microwave Drying.

Studies on methods for fixing foods (with a slight loss of bioactive compounds) and obtaining attractive products are important with respect to current technology. The drying process allows for a product with highly bioactive properties. Drying of Physalis fruit was carried out in a conventional manner, and in a microwave under reduced pressure at 120 W and 480 W. After drying, the fruits were subjected to strength and rheological tests. Water activity, content of carotenoids and polyphenols and antioxidant activity as well as colour were also examined. The study showed that Physalis is a difficult material for drying. The best results were obtained using microwave drying at a power of 480 W. Physalis fruit microwave-dried by this method is characterized by higher resistance to compression than the fruit dried by convection. Dried fruit obtained in this way was characterized by higher contents of bioactive compounds, better antioxidant properties, and at the same time the lowest water activity.

Comparison of old cherry cultivars grown in Czech Republic by chemical composition and bioactive compounds.

Sweet cherry fruits are readily consumed by humans, and they contain significant quantities of bioactive compounds. Fifteen sweet cherry (Prunus avium L.) old cultivars grown in the Czech Republic were examined. In fresh fruits the contents of sugars, organic acids, and phenolic compounds, and antioxidant capacity were determined. The analyses showed that the fruits of sweet cherry are characterized by high contents of bioactive compounds. Four organic acids - malic, quinic, shikimic, and fumaric acid - were determined in examined fruits. The cultivar 'Lyonská Raná' was characterized by the highest total polyphenol content (202.28mg GAE/100g FW) and high antioxidant activity (ABTS - 2765.3µmol TE/100g FW, FRAP - 1663.67µmol TE/100g FW), with the lowest content of organic acids. The 'Sakvická' cultivar was characterized by the highest content sum of sugars (16.36g/100g FW) and sweetness (19.08g/100g FW), with low contents of polyphenols and antioxidant activity.

Effect of Film-Forming Alginate/Chitosan Polyelectrolyte Complex on the Storage Quality of Pork.

Meat is one of the most challenging food products in the context of maintaining quality and safety. The aim of this work was to improve the quality of raw/cooked meat by coating it with sodium alginate (A), chitosan (C), and sodium alginate-chitosan polyelectrolyte complex (PEC) hydrosols. Antioxidant properties of A, C, and PEC hydrosols were determined. Subsequently, total antioxidant capacity (TAC), sensory quality of raw/cooked pork coated with experimental hydrosols, and antimicrobial efficiency of those hydrosols on the surface microbiota were analysed. Application analyses of hydrosol were performed during 0, 7, and 14 days of refrigerated storage in MAP (modified atmosphere packaging). Ferric reducing antioxidant power (FRAP) and (2,2-diphenyll-picrylhydrazyl (DPPH) analysis confirmed the antioxidant properties of A, C, and PEC. Sample C (1.0%) was characterized by the highest DPPH value (174.67 µM Trolox/mL) of all variants. PEC samples consisted of A 0.3%/C 1.0% and A 0.6%/C 1.0% were characterized by the greatest FRAP value (~7.21 µM Fe2+/mL) of all variants. TAC losses caused by thermal treatment of meat were reduced by 45% by coating meat with experimental hydrosols. Application of PEC on the meat surface resulted in reducing the total number of micro-organisms, psychrotrophs, and lactic acid bacteria by about 61%, and yeast and molds by about 45% compared to control after a two-week storage.

Colour, phenolic content and antioxidant capacity of some fruits dehydrated by a combination of different methods.

The objective of this study was to improve product quality of dehydrated fruits (apple, pear, papaya, mango) using combined drying techniques. This involved investigation of bioactivity, colour, and sensory assessment on colour of the dried products as well as the retention of the bio-active ingredients. The attributes of quality were compared in regard to the quality of dehydrated samples obtained from continuous heat pump (HP) drying technique. It was found that for apple, pear and mango the total colour change (ΔE) of samples dried using continuous heat pump (HP) or heat pump vacuum-microwave (HP/VM) methods was lower than of samples dried by other combined methods. However, for papaya, the lowest colour change exhibited by samples dried using hot air-cold air (HHC) method and the highest colour change was found for heat pump (HP) dehydrated samples. Sensory evaluation revealed that dehydrated pear with higher total colour change (ΔE) is more desirable because of its golden yellow appearance. In most cases the highest phenol content was found from fruits dried by HP/VM method. Judging from the quality findings on two important areas namely colour and bioactivity, it was found that combined drying method consisted of HP pre-drying followed by VM finish drying gave the best results for most dehydrated fruits studied in this work as the fruits contain first group of polyphenol compounds, which preferably requires low temperature followed by rapid drying strategy.