Stefano Buiatti

Determination of biogenic amines in alcoholic and non-alcoholic beers by HPLC

Abstract Eight biogenic amines (histamine, tyramine, tryptamine, 2-phenyl-ethylamine, putrescine, cadaverine, spermine and spermidine) in alcoholic and non-alcoholic beers have been determined by HPLC. The results obtained ranged between 0.1 and 17.2 ppm. Only six amines were found because histamine and spermine were not present in detectable amounts. Spermidine was detected in all samples (0.3–1·4 ppm) despite absence of references in the literature about the content of this amine in beers. Non-alcoholic beers did not have significantly lower amounts of biogenic amines than alcoholic beers.

Beer Composition: An Overview

Abstract The word beer comes from the old English bēor ; but its roots are from late latin biber (meaning drink), from bibere (to drink) which is the source of English “imbibe” and “beverage” ( Encarta World English Dictionary, 1999 ). Not surprisingly beer is not only the oldest alcoholic beverage but also the most important in terms of amount of volumes produced worldwide. In 2006 nearly 1,700,000,000 hl (one thousand and seven hundred million of hectoliters) of beer were drunk in the world. Hectoliter (hl) is equivalent to 100 l (175.98 UK pints or 211.29 US pints). The amount of wine, the other “historical” alcoholic beverage, produced in the world is about six times smaller (280,000,000 hl). Beers are quite similar in most respects but small differences in their composition can greatly affect both appearance and flavor. Apart from water which normally represents more than 90% of the beer, the only compound present with a concentration greater than 1 g/l are some carbohydrates not fermented by yeast, ethanol, carbon dioxide and glycerol. In spite of this fact beer, is a very complex beverage that contains, besides these compounds, about 800 organic compounds. Many of them have such a low level that only those having a flavor active impact can have a real influence on taste and smell perception. Most chemical compounds in beer were either present in the raw materials (malts, hops and water) or they are by-products of yeast metabolism during the fermentation and are responsible for most of the flavor character that is unique to beer.

Alcohol reduces MMP-2 in humans and isolated smooth muscle cells

Alcoholic beverages are known to exert a protective effect on atherosclerotic disease. This study aimed to assess the in vivo and in vitro effects of alcohol on matrix metalloproteinase (MMP) -2 and -9, known to determine atherosclerosis progression. Eighteen healthy volunteers, regular drinkers (two standard alcohol servings/day, on average) at first examination (baseline) were asked to abstain from any alcoholic beverage for one week (abstention), and then to assume two standard alcohol servings of beer daily for 1 week (re-exposure). Activity of MMP-2 and -9, total antioxidant activity (AOA), glutathione (GSH) plasma levels were carried out at baseline, at the end of abstention, and after 1 week of re-exposure. To validate the in vivo results, MMP-2 activity and expression, AOA, and GSH, were determined in human smooth muscle cells treated for 96 h with increasing concentrations (12.5-100 mM) of ethanol. MMP-2, but not MMP-9 plasma activity was higher at abstention than at baseline or re-exposure (P<.001 and P< or =.005, respectively). Changes in AOA and GSH throughout the study were not significant. No correlation was found between MMPs and antioxidant activity. In vitro, ethanol at 25 mM reduced by around 10% MMP-2 activity (P=.003) in smooth muscle cells, whereas MMP-2 expression, AOA, and GSH were unaffected. Alcohol reduces MMP-2 plasma activity in healthy humans and in isolated vascular smooth muscle cells. This in vitro reduction is unrelated to MMP-2 expression in vascular cells or to antioxidant levels changes.

2 – Non-lager Beer

Many thousands of different beer brands are produced worldwide and most of them can be classified into defined beer styles which have developed over the course of time in different countries or regions. Depending on the process used, a first classification can be made according to the fermentation process in top and bottom fermentation beers. Top fermented beers represent only a small percentage of the total beer consumption. Top fermented beers are very common in Britain, Germany, Canadas eastern provinces, United States and, last but not least, Belgium. However, lager (the term generally used for bottom fermented beer) is the dominant style in almost all countries and represents more than 90% of the beer produced worldwide. Until the sixteenth century, ale (the term generally used for top fermentation beers) was the main type of beer in Europe. Traditionally, ales are fermented with the use of top-cropping yeasts which rise to the top of the beer in the head of foam at temperatures between 16°C and 24°C. At these temperatures, the yeast produces significant amounts of esters and other secondary flavor and aromatic products, and the result is often a beer with slightly “fruity” compounds. Typical ales have a sweeter, fuller body than lagers.

25 – Amino Acids in Beer

Abstract Nitrogenous compounds are considered very important in beer playing a key role in determining the quality and stability of the finished product. They include amino acids, peptides, polypeptides, proteins, nucleic acids and their degradation products. These compounds affect flavor, foam stability, haze formation, color, yeast nutrition and biological stability. The nitrogenous compounds in beer are derived mainly from barley malt and its adjuncts. Moreover the brewing process may have an important role in determining complex profile of nitrogenous compounds present in the final beer. The content of nitrogen compounds in barley depends on variety and on environmental condition in cultivation. During malting the storage proteins are degraded to amino acids and other peptides. These amino acids are important in wort to promote a good fermentation and the yeast budding. During fermentation amino acids are used in different ways by yeasts and may have many effects on the final quality of beer: in particular the amino nitrogen content influences the flavor profile of beer. The amino acids present in final beer could influence negatively the stability of product promoting haze formation. Nitrogen compounds may also play an important role influencing the foam quality and stability.

Food and tourism: the role of the “Slow Food” association

Tourism is an important economic activity in many countries, especially in Italy where the tourism industry is one of the major economic activities in terms of turnover. It is necessary that the traditional tourism activities, in particular those specialized in food tourism, develop a sensitivity to protect and integrate with the natural and cultural resources available in the territory. This paper analyses the role of intermediaries to create such awareness by focusing on the case of “Slow Food”. Through the “tools” Ark of Taste and Presidia, the “Slow Food” association aims to protect food heritage, saving endangered food species through the “Slow Food Foundation of Biodiversity”. Through food tourism it is important to generate economic development that can help preserve natural resources and improve the quality of life of the communities in a region. This ensures that indigenous food and production methods are not lost in the face of globalisation.

Monitoring of some selected heavy metals throughout the brewing process of craft beers by inductively coupled plasma mass spectrometry

Herbicides, fungicides and bactericides containing heavy metals used in agriculture make it possible to find these toxic metals in beer (Čejka et al. in Ecol Chem Eng S 18:67–74, 2011). The aim of this work was to monitor the distribution of some toxic heavy metals such as cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) zinc (Zn), iron (Fe) and arsenic (As) during craft beers production (three types of beer produced in four different breweries). The instrumental method adopted in this investigation was inductively coupled plasma mass spectrometry. The collected results demonstrated how a very low (µg/L) heavy metal contamination (mainly Cr, Zn and Cu) was provided by raw materials (water, malt, hops and yeasts) and that these toxic metals mostly pass into the residuals (spent grains, hottrub and yeasts), so only a negligible fraction of them can be detected in beer. For example, treating hops with a high dose of pesticides containing Cu did not cause an increase in its content in final beer because a large part of copper remains in hot trub. Furthermore, the filtration phase caused the increase in the concentration of Cd, Zn, Fe and As, probably due to the use of filtration aids. These increases were insignificant healthwise [http://www.edqm.eu/en/Metals-and-alloys-used-in-food-contact-materials-and-articles-1st-Edition-(CouncilofEurope,2002)]. The craft beers produced without the final filtration did not present this increase. Pb and Ni were always found below the detection limits.

Influence of gluten-free adjuncts on beer colloidal stability

This work deals with issues related to the colloidal stability of craft beers. It is generally known that haze in beer is directly related to the formation of complexes resulting from the interaction of haze active polyphenols and protein fractions [1–18]. How some variables in the malting process and formulation can contribute to the colloidal stability of the final beer have been considered. Micro malting tests on four glutenfree cereals/pseudocereals (millet, amaranth, buckwheat and quinoa) were carried out in order to identify the optimal conditions for obtaining malts suitable for brewing. Quality of malts was checked analysing diastatic power, beta glucans content and Kolbach Index. The gluten-free malts were under-modified if compared to traditional malts, but potentially suitable as adjuncts (especially buckwheat). Nine beers with different formulations were produced in the laboratory using the malts obtained from the micro malting tests. The evaluation of beer stability was carried out analyzing indices validated by European Brewery Convention (sensitive proteins and cold turbidity) and two unconventional methods (gluten analysis and antioxidant activity). Moreover, three beers (the reference obtained with 100% malted barley, the other two with the buckwheat malts) were subjected to CE analyses (Capillary Electrophoresis) in order to define their protein content. According to the results the use of gluten-free adjuncts, besides relevant process conditions (i.e. alkalinized first steeping water in the malting process), can lead to more stable final products with a gluten content less than 100 mg/L and so potentially suitable by coeliacs according to EU regulation 828/2014.

3 – Lager Beer

Beer is one of the worlds oldest alcoholic beverages. Brewing industry is a huge global business, consisting of several multinational companies and many thousands of smaller producers ranging from brewpubs to regional breweries. A great many of different types, or style, of beer are brewed across the world. For this reason, it is difficult to generalize on the relationship between beer and relative impact on nutrient intake because the composition of beers will range quite considerably depending on raw materials and how they are produced. Lager represents more than 90% of beer produced worldwide. It is typically brewed at low temperatures (bottom fermentation) in cool conditions using a particular yeast, and then stored (the word “lager” comes from the German lagern meaning “to store”) in cool conditions to have maturation or improvement of its organoleptic characteristics. Until the sixteenth century ale (top fermentation) was the main type of beer in Europe. So it is only a myth that lager-style products have always been the characteristic beer in Germany. The monks of Bavaria were responsible for an innovation that was to change the face of beer brewing, the “bottom fermentation.” The Bavarian monasteries first attempted to store beer for long periods in cool cellar. At lower temperatures, instead of frothing to the top of the fermenting vessel, the yeast sank to the bottom end fermenting more slowly. The Bavarian lager was still different from the widely known modern lager. They remained a fairly conventional dark brown or amber-red color, until 1842, when Joseph Groll mashed his first batch of beer in Plzeň (in Czech Republic) and the worlds first ever golden colored lager was born.