Paolo Fantozzi

Beer increases plasma antioxidant capacity in humans

The positive association of a moderate intake of alcoholic beverages with a low risk for cardiovascular disease, in addition to ethanol itself, may be linked to their polyphenol content. This article describes the effect of acute ingestion of beer, dealcoholized beer, and ethanol (4.5% v/v) on the total plasma antioxidant status of subjects, and the change in the high performance liquid chromatography profile of some selected phenolic acids (caffeic, sinapic, syringic, and vanillic acids) in 14 healthy humans. Plasma was collected at various times: before (T0), 1 hour after (T1), and 2 hours after (T2) drinking. The study is part of a larger research planned to identify both the impact of brewing on minor components potentially present in beer and their metabolic fate in humans. Beer was able to induce a significant (P < 0.05) increase in plasma antioxidant capacity at T1 (mean +/- SD: T0 1,353 +/- 320 microM; T1 1,578 +/- 282 microM), returning close to basal values at T2. All phenolic acids measured in plasma tended to increase after beer intake (20% at T1, 40% at T2). Syringic and sinapic acid reached statistical significance (P < 0.05 by one-way analysis of variance-Fishers test) at T1 and T2, respectively. Plasma metabolic parameters (glucose, total cholesterol, triglycerides, and uric acid) and plasma antioxidants (alpha-tocopherol and glutathione) remained unchanged. Ethanol removal impaired the absorption of phenolic acids, which did not change over the time of the experiment, accounting for the low (and not statistically significant) increase in plasma antioxidant capacity after dealcoholized beer drinking. Ethanol alone did not affect plasma antioxidant capacity or any of the antioxidant and metabolic parameters measured.

Optimal conditions for alginate production by Azotobacter vinelandii

Alginate production from glucose-based media by Azotobacter vinelandii DSM 576 was studied in the shaken-flask scale at different temperatures (23–42°C), shaking speeds (250–450 min−1), and initial concentrations of yields glucose (10–100 g l−1). When buffering the culture medium, alginate (YAS) and bacterial biomass were optimized with respect to the CN ratio and acetate (Ac) and phosphate (Ph) concentrations by performing a composite design experiment. The experimental yields were fitted to the only statistically significant factors with mean percentage errors smaller than 15% and 12%, respectively. The resulting empiric models were used to estimate the CN ratio (110 g-atom C per g-atom N) and concentrations of acetate and phosphate associated with optimum alginate yields ranging from 25 to 33% of the glucose supplied. More specifically, phosphate limitation (0.035 g l−1) and no acetate addition resulted in maximum alginate production with respect to the case of excess of phosphate (3.5 g l−1) and acetate (3 g l−1). Further trials permitted us to assess that the alginate yield was hampered by any sodium acetate addition; however, YA/X was insensitive to Ph concentrations and CN ratios in the ranges 0.035–1.8 g l−1 and 60–110 g-atom C per g-atom N, respectively, in acetate-free media.

Beer Affects Oxidative Stress due to Ethanol in Rats

The relationship between chronic moderate beerconsumption and oxidative stress was studied in rats.Animals were fed three different isocaloric diets forsix weeks: a beercontaining diet (30% w/w), an ethanol-supplemented diet (1.1 g/100 g, thesame as in the beer diet) and an alcohol-free basaldiet. At the end of the feeding period, rats wereanalyzed for plasma and liver oxidative status. Somelivers were isolated and exposed toischemiareperfusion to assess the additional oxidativestress determined by reperfusion. No significantdifferences in plasma antioxidant status were foundamong the three dietary groups. Lipoproteins from the beer group,however, showed a greater propensity to resist lipidperoxidation. Ischemia caused a decrease in liver energyand antioxidant status in all groups. Nevertheless, ATP was lower in the livers of rats exposed tothe ethanol diet. During reperfusion, lipoperoxidationincreased significantly in all groups. However, liversobtained from ethanoltreated rats showed the higher formation of lipoperoxides. Inconclusion, a moderate consumption of beer in awell-balanced diet did not appear to cause oxidativestress in rats; moreover, probably through its minorcomponents, beer could attenuate the oxidative action ofethanol by itself.

Production of alcohol-free beer

With greater interest in health and concern about weight and considering the warnings about alcohol abuse, especially when driving, consumer preference for low-alcohol and alcohol-free beer is increasing, but the definitions of “low-alcohol” and “alcohol-free” beers vary in different countries as well as their composition. Low-alcohol or any other word or description which implies that the drink being described is low in alcohol may not be applied to any alcoholic drink unless: (a) the drink has an alcoholic strength by volume of not more than 1.2% and (b) the drink is marked or labeled with an indication of its maximum alcoholic strength immediately preceded by the word “not more than.” The most common way to produce non-alcoholic beers is to modify the normal brewing process so that fermentation is limited and almost no ethanol is produced. There are several techniques for determining alcohol concentration by controlling the extent of fermentation. Moreover, beers produced in a traditional way and in different brands can be made alcohol-free by using physical methods to remove the alcohol at the end of the production process. The biological methods used to produce alcohol-free beers do not usually require special extra plant, but rather a more accurately controlled process to prevent an overproduction of alcohol.

Technological steps and yeast biomass as factors affecting the lipid content of beer during the brewing process.

Knowledge of lipid content and composition in the brewing process enables the quality control of the final product. Lipids have a beneficial effect on yeast growth during fermentation as well as deleterious effects on end-product quality. The lipid content of a beer affects its ability to form a stable head of foam and plays an important role in beer staling. Lipid oxidation during wort production is of great interest because of its effect on beer quality: both lipids and their oxidation products are known to have adverse effects on beer flavor, whereas interactions between lipids and protein films stabilizing the gas bubbles are thought to cause the collapse of foam. In this background, the aim of this research was the characterization of the lipid content during a brewing process for evaluating the influence of both technological steps and yeast biomass in the lipid composition of beer. Lipid contents and their fatty acid profile were evaluated in brewing raw materials, wort, and beer. A high-resolution gas chromatography-flame ionization detector (HRGC-FID) system was used for fatty acid determination in lipid extracts. The results of the present study highlighted that the main technological steps influencing the lipid content in brewing byproduct and beer were clarification in a whirlpool and filtration. Moreover, the presence of metabolically active yeast cells (used as starter culture) were found to have a great influence on the fatty acids composition of lipids.

Influence of barley variety and malting process on lipid content of malt

The lipid content of a beer affects its ability to form a stable head of foam and plays an important role in beer staling. The concentration and the quality of lipids in beer depend on their composition in the raw materials and on the brewing process and they may exert considerable influence on beer quality. This paper presents an investigation of the influence of barley variety and malting process on the lipid content of finished malt. Five barley samples, grown in Italy, representing 4 spring barley and 1 winter barley were used. The samples were micro-malted and analysed. The aim of this research was to verify the influence of different barley varieties on the lipid content of malt and also on the changes in fatty acid (FA) profile during the malting process. Lipid content and FA profile were evaluated. Principal component analysis (PCA) was used to establish relationships between the different samples. An evaluation of the correlation between lipid content of barleys and the quality of the resulting malts was also conducted. The data showed that the total lipid content during the malting process decreased significantly as barley was converted into malt. Different barley varieties present different FA contents and different FA patterns. The correlation between the lipid content of barley and the quality of the resulting malt confirmed the negative influence of lipids.

Systemic nicotine exposure in tobacco harvesters

Abstract Several epidemics of nicotine intoxication have been described among tobacco harvesters; however, little is known about nicotine absorption under typical working conditions. To assess systemic nicotine absorption during a regular working shift, the authors performed an observational field study. Included in the study were 10 healthy, nonsmoking, female tobacco harvesters and a control group of 5 healthy, nonsmoking, female hospital workers. Nicotine and cotinine were measured in sequential samples of blood and urine during a regular workshift. Blood nicotine levels rose from a nadir value of 0.79 ± 0.12 ng/ml to a peak value of 3.45 ± 0.84 ng/ml (p < .05 [Tukeys modified t test]) in the exposed group. In the control group, levels were stable at 0.1 ± 0.1 ng/ml (p < .01). Moreover, the mean blood nicotine level measured 3 mo following the end of exposure in 6 of 10 exposed subjects was 0.24 ± 0.12 ng/ml (p < .01). Corresponding higher values of urine nicotine and urine cotinine were observed in the exposed versus control group (comparative P values were < .01 and < .05, respectively). Overall, tobacco harvesters absorbed approximately 0.8 mg of nicotine daily. Given that nicotine can induce adverse health effects, the authors believe that prevention of nicotine absorption in tobacco harvesters should be sought and that workers should be informed about occupational risks.

Composition and oxidative stability of borage (Borago officinalis L.) and borage—virgin olive oil blends

The oxidative stability of borage ( Borago officinalis L.) oils from commercial origin or extracted by different methods (with solvents and supercritical CO 2 ) was determined by the Rancimat method. To delay the oxidative degradation with the aim of preserving the nutritional characteristics of borage oil, several borage—virgin olive oil blends were prepared and submitted to analysis. The results indicated that the incorporation of borage in virgin olive oil (to a level not exceeding 50 g/kg) while modifying the fatty acid profile of the resulting blends had a limited effect on the oxidative stability provided that the blends were maintained in the absence of light.

Effects of malting on molecular weight distribution and content of water-extractable β-glucans in barley

In the beer industry β-glucans are extensively studied non-starch polysaccharides due to their ability to increase the viscosity of solutions and to form gels. The current study was designed to determine the total and water-soluble β-glucan contents of barley during malting. Total and water-soluble β-glucans were analyzed from two different malts that originated from the same barley but varied in germination time from 36h (malt A) to 72h (malt B). Water-soluble β-glucans were also characterized using high-performance size-exclusion chromatography with triple-detector analysis (HPSEC-TDA) to evaluate the variation in molecular weight distributions, intrinsic viscosity, radius of gyration, Mark-Houwink parameters and polydispersity and thus the overall structural changes during malting. Total β-glucan content decreased from barley to malt due to the action of β-glucanase and was greatest in malt B (where 92% of β-glucans were degraded) which highlights the influence of germination time. β-Glucan solubility increased during malting, again particularly in malt B, where most of β-glucans became soluble. The β-glucanase activity also affected the molecular weight of the polymers which ranged from 298·103g/mol in barley to 293·103 and 218·103g/mol in malts A and B respectively. The molar mass of the most abundant fraction decreased from barley (256·103g/mol) to malt A (112·103g/mol) and malt B (89·103g/mol), again highlighting the effect of the longer germination time. Proceeding from barley to malt, the cumulative molar mass distribution function confirmed that the weight fraction of polymers below 200·103g/mol increased, while the high molecular weight fraction (between 200·103g/mol and 400·103g/mol) decreased. Moreover, the presence of a higher molecular weight fraction (14-16%) beyond 400·103g/mol which does not change during malting was observed. The Mark-Houwink constants α and log k confirmed the random coil conformation of soluble β-glucans and showed an increase in the compactness of the macromolecules from barley to malts.

Grape seed: A potential source of protein

Because grape seed is a potential source of edible protein, it is essential to remove the polyphenols to significantly improve protein digestibility. This study describes a procedure whereby grape seed protein concentrate is significantly purified and protein digestibility is improved. The procedure involves soaking whole seeds in an alkaline solution and subsequently extracting the protein with a concentrated salt solution.