Malt Samples Research Articles

Accurate quantification of small and large starch granules in barley and malt

The proportion of small and large starch granules in barley and malt is often neglected, leading to underestimation of their importance in processes in which they are used. This study aimed to accurately determine the volume and number based percentages of small and large starch granules for three barley varieties, their micro-malted malts and three commercial malts. Quantitative starch isolation was performed and starch granule proportions were estimated using microscopic and image analysis, taking the non-sphericity of the large starch granules into account. Results show that barley starch consists of 32–39 volume% of small starch granules. Upon malting, this percentage is reduced to 17–27 volume%, showing that small granules are hydrolyzed faster than large granules during this process. The analyzed commercial malt samples have a small starch granule content of 22–25 volume%. Malt hence still contains a substantial amount of small starch granules, which can be expected to impact processing.

Validation of an ultra-high-performance liquid chromatography-mass spectrometry method for the quantification of cysteinylated aldehydes and application to malt and beer samples

This paper describes the method validation for the simultaneous determination of seven cysteinylated aldehydes, i.e. 2-substituted 1,3-thiazolidines-4-carboxylic acids, using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC–MS). Authentic reference compounds were first synthesized for identification and quantification purposes. Moreover, nuclear magnetic resonance (1H NMR and 13C NMR) was applied for verification of their structure, while ultra-high-performance liquid chromatography–mass spectrometry (UHPLC–MS) was applied for estimation of the purity. The method for quantification of cysteinylated aldehydes in model solutions has been validated according to the criteria and procedures described in international standards. The synthesized compounds were successfully identified via UHPLC–MS by comparing retention time and MS spectra with the commercial reference compounds. Method validation revealed good linearity (R2 > 0.995) over the range of 0.4–2.2 µg/L to approximately 1000 µg/L, depending on the analyte. The limits of quantification varied from 0.9 to 4.3 µg/L depending on the nature of the compound. Furthermore, evaluation of the method showed good accuracy and stability of the standard solutions. Reported chromatographic recoveries ranged from 112 to 120%. Consequently, the currently described method was applied on malt and beer samples. For the first time, quantification of cysteinylated aldehydes was obtained in malt. In contrast, in fresh beers unambiguous identification of these compounds was not achieved.

Selenium species in selenium-enriched malt

Selenium-enriched malts were prepared by an application of sodium selenite solution to steeped barley grain and following germination and kilning. The changes of selenium valency and the biotransformation of inorganic selenium were investigated by selenium speciation analysis in enzyme-hydrolysed malt samples using liquid chromatography-inductively coupled plasma mass spectrometry. Both inorganic compounds (selenate, selenite) and Se-containing amino acids (selenocystine, Se-methyl-selenocysteine, selenomethionine) were found in green and kilned barley malt.

Pullulation of toxigenic Fusarium and Deoxynivalenol in the malting of de minimis infected barley (Hordeum vulgare)

Malting barley is the main grain ingredient of beer brewing, but the grain crop is susceptible to Fusarium worldwide. In the study, effect of malting on the development of Fusarium toxigenic tri5 DNA and Deoxynivalenol (DON) was evaluated on barleys of naturally de minimis contamination by means of quantitative PCR and LC/MS, respectively. Twenty malting barley samples were collected from Chinese market and represented a range of DON levels below 0.75 mg/kg. The DON level was prone to decrease or remain consistent in 18 malts, but it increased in 2 malts. DON levels in the 20 malt samples were all below 0.70 mg/kg, and they were 78% on average of that presented on initial ungerminated barley. Fate of Fusarium tri5 DNA and DON was tracked during the malting of 5 barley samples, in which DON levels developed diversely. It was found that the dramatic growth of steeping-remained Fusarium was responsible for DON reproduction in barley germination, with 4.8-fold increase of tri5 DNA level on average. It made sense of the correlation (R2 = 0.753) of barley tri5 DNA contents with malt DON levels (n = 20). Results in the current study demonstrated the growth of Fusarium and DON production in the malting of barley that potentially tended to be utilized in practical beer production.

The Pressure of Fusarium Disease and Its Relation with Mycotoxins in The Wheat Grain and Malt.

Fusarium head blight (FHB) is one of the most destructive wheat fungal diseases, causing yield loss, quality reduction, and accumulation of mycotoxins. The aim of this research was to summarize the occurrence of major Fusarium mycotoxins: deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-AcDON), nivalenol (NIV), and zearalenone (ZEN) in two consecutive years to search the relationship between disease incidence and severity with mycotoxins found in control and inoculated grains and corresponding malt. In addition, deoxynivalenol-3-glucoside (D3G) in one-year research was measured. Tested wheat varieties showed infection scores of 3% (‘U1’ and ‘Sirban Prolifik’) to 79% (‘Golubica’) for Type I resistance evaluation. There were few moderately resistant varieties in view of their areas under the disease progress curve, which can be considered Type III resistance (‘Sirban Prolifik’ and ‘U1’). According to the data quantified by LC–MS/MS, DON decreased in infected malt in comparison to corresponding grain, while ZEN occurred only in infected malt samples. Both 3-AcDON and NIV increased in inoculated malt in comparison to corresponding grain, due to a combination of plant metabolism and de novo synthesis by molds during malting. Based on the results, we can draw a few conclusions: the resistance to Fusarium decreased quantified concentrations of DON; ZEN gets synthetized during malting; unregulated 3-AcDON and NIV increase during malting; more resistant varieties have converted DON to D3G more successfully. Modified mycotoxins should be also included to legislation, since they could be transformed back to the corresponding mycotoxins under food processing conditions or during digestion.

Multielemental Analysis of Various Kinds of Whisky.

Whisky (whiskey) consists of many trace elements coming from the raw materials used in its fermentation, distillation and maturation processes. These ingredients assure the exceptional organoleptic characteristics of the beverage. Their analysis is important to better control the stages of fermentation, distillation, taste repeatability and for product quality assurance as well as from the brand protection point of view. This article presents the usefulness of modern analytical techniques based on elemental analysis. ICP mass spectrometry and CV atomic absorption spectroscopy were applied to distinguish whisky produced in Scotland from whisky coming from Ireland and the United States. The collected semi-quantitative data were used for multivariate analysis performed using the Statistica 10.0 software. The results showed that Irish whiskey is characterized by quite a high amount of Ba and Ti compared with other samples, which made it possible to distinguish this sample from the others. No strict correlation was found between the type of whisky and the amount of trace elements, however, the projection of objects on the first two components revealed that single malt samples created one cluster.

Effect of Aframomum danielli Extract on the Quality of Non Alcoholic Malt Beverage Produced from Quality Protein Maize (QPM) at Storage

Non alcoholic malt beverage from maize and other cereals has a short shelf life. The aim of this study was to evaluate the effect of Aframomum danielli extract on the shelf life of non alcoholic quality protein maize (QPM) malt beverage stored at ambient and refrigerated conditions. The stored malt samples were assessed for physical observation, physicochemical characteristics, microbial properties and sensory qualities. The results showed that non Aframomum danielli treated sample at ambient temperature was spoilt by day 3. Aframomum danielli treated sample at refrigerated condition was wholesome till day 28. The pH reduced with days of storage in all the malt beverage samples. Non A. danielli treated sample at refrigerated condition had the highest °Brix. Total viable count was least in A. danielli treated malt sample at refrigerated condition (day 28). A. danielli treated malt sample at refrigerated condition was acceptable throughout the storage period for sensory attributes. Malt beverage could be produced from quality protein maize (a maize variety with twice lysine content than in ordinary maize). QPM malt beverage treated with A. danielli could keep for 7 days at ambient temperature and 28 days at refrigerated condition. With the shelf-life findings in this study, QPM malt beverage could be produced, consumed and sold at household and small scale levels.

Development and Validation of UV-Visible Spectrophotometric Method for the Determination of 5-Hydroxymethyl Furfural Content in Canned Malt Drinks and Fruit Juices in Ghana

A simple, rapid, accurate, and less expensive spectrophotometric method has been developed for the quantitation of 5-hydroxymethyl furfural (5-HMF) levels in canned malt drinks and fruit juice drinks sampled in the Kumasi Metropolis, Ghana. The quantitation is based on the selective maximum absorption of ultraviolet radiation by 5-HMF at the wavelength (λmax) of 284 nm using acetonitrile : water (50 : 50 v/v) as the solvent system. The method was established to be specific, precise, and accurate over a concentration range of 0.001 mg/ml–0.02 mg/ml. 5-HMF levels in fruit juice samples (A1–A10) were between 0.132 mg/ml and 0.438 mg/ml, and these levels were shown to be comparable (t = 2.200;p=0.0553) to the contents in the canned malt samples (M1–M10) which were between 0.3140 mg/ml and 0.7170 mg/ml. The study failed to show any dependence of 5-HMF levels on the composition of the product as well as the manufacturing process adopted. The length of storage did also not significantly affect the 5-HMF levels in the products.

Fusarium culmorum mycotoxin transfer from wheat to malting and brewing products and by-products

The objectives of this study were to establish the impact ofFusarium culmorum infection and fungicide treatment on the occurrence of deoxynivalenol (DON), 3-acetyl deoxynivalenol, T-2 toxin, HT-2 toxin, nivalenol, fusarenon-X, diacetoxyscirpenol and zearalenone in wheat, wheat malt and wort (beer). The concentrations of these compounds were also measured in the germ/rootlets, spent grains and spent yeast because these are the most important by-products and are further used as food or feed additives. Two wheat genotypes were obtained from the Agricultural Institute in Osijek, Croatia. The Osk.110/09 genotype, the genotype more susceptible toFusarium infections, and Lucija, the genotype less susceptible toFusarium, were analysed in this research. Each genotype was treated in four different ways at the field: (A) control, (B) treated with fungicide Prosaro® 250, (C) inoculated withF. culmorum spores and treated with fungicide Prosaro® 250, and (D) inoculated withF. culmorum spores. All samples were malted and brewed according to standard procedures, products and by-products were analysed for the mycotoxins by using LC-MS/MS. Since the majority of trichothecenes are polar molecules, the water after steeping was also analysed with LC-MS/MS. Mycotoxin concentrations were lower in malt samples treated with the fungicide. Elevated mycotoxin concentrations were observed in samples of both genotypes exposed toF. culmorum. Fungicide treatment was observed to suppress mycotoxin production and accumulation. However, samples with notably high mycotoxin concentrations, especially DON, retained elevated mycotoxin concentrations throughout the entire beer production process, even after a six-month storage period. DON proved to be the most frequently occurring mycotoxin in all of the by-products. The highest concentration of this compound was found in the steeping water from sample D (Osk.110/09), at 20,326 μg/l, leaving the spent grains of this sample with no detectable levels of DON.

Sugar Profile of Syrups from Malted and Unmalted Rice of Different Varieties

Rice syrup was produced from ten varieties of locally available rice in Nigeria. Flours of malted and unmalted rice from different varieties were treated with a combination of starch hydrolyzing enzymes (Amyloglucosidase, Bacterial α-amylase and Fungal α-amylase); and the starch hydrolysates were either filtered and/or centrifuged at the end of hydrolysis. The resulting rice syrup was evaluated for sugar compositions (maltose, glucose, maltotriose, sucrose, raffinose and stachyose) using HPLC. The results showed that syrups from malted rice had significantly higher (p<0.05) maltose and maltotriose concentration than syrups from unmalted rice. The resultant syrup is a ‘High Maltose Syrup’ since maltose was found to be the predominant sugar in the rice syrup with concentration of above 50% especially for malted samples. Rice syrup can be widely applied as a potential raw material in beverage and confectionery industries as well as a good adjunct for brewing since the sugar profile of the rice syrup was similar to that of barley wort.

Effect of varying starch properties and mashing conditions on wort sugar profiles

The aim of this research was to investigate the relationship between starch composition in barley and its malted counterpart alongside malt enzyme activity and determine how these factors contribute to the fermentable sugar profile of wort. Two Australian malting barley varieties, Commander and Gairdner, were sourced from eight growing locations alongside a commercial sample of each. For barley and malt, total starch and gelatinisation temperature were taken, and for malt, α- and β-amylase activities were measured. Samples were mashed using two mashing profiles (infusion and Congress) and the subsequent wort sugar composition and other quality measures (colour, original gravity, soluble nitrogen) were tested. Variety had no significant (<0.05) effect on any barley, malt, enzyme or wort characteristics. However, growing location impacted gelatinisation temperature, colour, malt protein content and original gravity. The gelatinisation temperature in malt samples was higher, by ~0.8°C, than in the equivalent barley sample. Several malt samples, even with protein contents <12.0%, had gelatinisation temperature >65°C. The fermentable sugars measured in the malt prior to mashing showed a higher proportion of maltose than glucose or maltotriose. In addition, there were significant differences in the amount of sugar produced by each mashing method with the high temperature infusion producing a higher amount of sugar and proportionally more maltose. There is scope for further research on the effect of genetics and growing environment on gelatinisation temperature, mash performance and fermentable sugar development. Routinely measuring gelatinisation temperature and providing this information on malt specification sheets could help brewers optimise performance. © 2019 The Institute of Brewing & Distilling

β-Glucanase Addition in Brewing Malt Produced by Reduced Time of Germination

Abstract The β-Glucans content has straight influence on the quality of malt and beer, mainly during the filtration step. Barley presenting high β-Glucan content demands longer germination time at malting. The application of commercial β-Glucanase is an alternative to accelerate the process and preserve the quality of malt. This work aimed to evaluate the effect of commercial β-Glucanase addition in malt produced within reduced germination time (64 h). Micro-malting was conducted with BRS-Caue and Elis barley cultivars at germination time 64 h and 96 h. The β-Glucanase concentration applied were 0, 25, 50 and 100 mg.kg-1. Barley, malt and wort samples were analyzed to check their physical-chemical features. Beers were produced with BRS-Caue malt and the physical-chemical and sensory attributes were analyzed. The commercial enzyme addition in BRS-Caue and Elis (64 h), at concentration 25 and 50 mg.kg-1, resulted in wort presenting proper β-Glucan content (≤ 178 mg.L-1). The beer produced with malt germinated for 64 h and added with 50 mg.kg-1 of β-glucanase was the one showing the largest number of physical-chemical and sensory parameters similar to the beer made with malt germinated for 96 h (conventional process). Commercial β-glucanase application in malt allowed accelerating the malting process without affecting the quality of the malt for beer production.

Vliv ošetření zrna ječmene a sladu výbojem nízkoteplotního plazmatu na gushingový potenciál sladu

In 2015, the effect of treatment of spring barley grain and malt produced from it with low-temperature plasma discharge on the malt gushing potential was studied. Malting barley and malt produced from it were plasma-treated. In the malt samples, the gushing potential was determined. Simultaneously, selected quality parameters were assessed in the malt samples (Kolbach index, diastatic power, β-glucan content in wort, final attenuation, extract of malt in dry matter, relative extract at 45 °C, and friability). Gushing declined in the plasma-treated samples of malting barley or malt. The malt quality parameters remained unchanged.

Validation of QuEChERS for screening of 4 marker polycyclic aromatic hydrocarbons in fish and malt

Application of QuEChERS as a new quick and easy method for screening of polycyclic aromatic hydrocarbons (PAHs) was developed, validated and used for quantification (GC-QTOF-MS) of 4 PAHs, namely benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene. A clean-up step using Zirconium based dispersive SPE was applied. Validation based on spiked samples (0.5, 1 and 4 μg/kg) revealed a limit of quantification (LOQ) for the 4 PAH compounds in the range of 0.14–0.24 μg/kg for fish and 0.12–0.24 μg/kg for raw barley. Overall recoveries ranged from 88 to 117% with repeatability and in-house reproducibility from 2.6 to 16%. The method was applied to 9 malt samples which were found to contain the sum of 4 PAH from <0.36 μg/kg for raw barley to 26 μg/kg for peat smoked barley. For 5 smoked fish samples the sum of PAH4 ranged from <0.34 μg/kg for cold smoked salmon to 2.2 μg/kg for hot smoked mackerel. In general it was found that the method could be used as a fast screening for evaluation of smoked fish according to EU Commission maximum concentrations of benzo[a]pyrene (2.0 μg/kg) and the sum of PAH4 (10 μg/kg).

Biosorptive detoxification of zearalenone biotoxin by surface-modified renewable biomass: process dynamics and application.

Contamination of food, feed, beverages and even drinking water with biotoxins is a growing global concern because of their potential health risks. In this work, surface-modified sugar beet pulp waste was used for the biosorptive removal of zearalenone biotoxin from contaminated aquatic media. Infrared, Boehm titration, BET (Brunauer-Emmett-Teller) surface area and point of zero charge analysis were employed for surface characterization. Kinetic and equilibrium studies showed that biotoxin biosorption was well predicted by the pseudo-second-order kinetic model and the Langmuir isotherm model. Zearalenone was removed from the solution over a wide pH range (3.0-8.0) and within a short time (15 min). Maximum uptake capacity of modified biomass was recorded as 23.30 ± 0.17 g kg-1 . Highest removal yield in a dynamic flow mode (94.56 ± 0.13%) was achieved at 2 mL min-1 flow rate using 30 mg biosorbent. Regeneration experiments revealed high reusability potential of suggested biosorbent. Moreover, its application potential was tested in spiked samples of malt, beer and canned corn liquid. Detoxification potential of this renewable biomass was significantly enhanced after modification. Modified biomass could be used as an efficient and low-cost green-type material with good application potential for zearalenone detoxification. © 2018 Society of Chemical Industry.

Impact of cooking methods and malting on amino acids content in amaranth, buckwheat and quinoa

This study reports the effect of boiling, steaming and malting on the amino acid composition of the pseudocereals amaranth, buckwheat and quinoa. For all pseudocereals the foremost amino acid was glutamic acid, presenting 13.2% in both raw and malted (2.2 g/100 g), and 15.6% in steamed (2.5 g/100 g) amaranth; 10.8% in steamed (2.0 g/100 g) and 17.6% in boiled (2.1 mg/100 g) quinoa; 15.4% in malted (2.3 g/100 g) and 21.2% in raw (2.8 g/100 g) buckwheat. Almost all amino acids present in the three pseudocereals evinced a significant increase of the retention values in malted samples, except in amaranth and quinoa for cysteine and glutamic acid, respectively. Histidine and aromatic amino acids presented the highest values of amino acid scores. Cluster analysis allowed to identify the pseudocereals with the highest nutritional protein quality, were boiled and malted quinoa and raw and malted buckwheat were included. Malting process revealed to be the method that produce more effect on the amino acid content for all pseudocereals.

Malting of Fusarium Head Blight-Infected Rye (Secale cereale): Growth of Fusarium graminearum, Trichothecene Production, and the Impact on Malt Quality.

This project was initiated with the goal of investigating the malt quality of winter rye cultivars and hybrids grown in the United States in 2014 and 2015, but high levels of deoxynivalenol (DON) were subsequently found in many of the malt samples. DON levels in 75% of the investigated rye samples (n = 117) were actually below 1.0 mg/kg, as quantified by a gas chromatography combined with electron capture detector (GC-ECD). However, 83% of the samples had DON in excess of 1.0 mg/kg following malting, and the average DON level in malted rye was 10.6 mg/kg. In addition, relatively high levels of 3-acetate DON (3-ADON), 15-acetate DON (15-ADON), nivalenol (NIV), and DON-3-glucoside (D3G) were observed in some rye malts. Our results show that rye grain DON is likely a poor predicator of type B trichothecenes in malt in practice, because high levels of malt DON, 15-ADONm and D3G were produced, even when the rye samples with DON levels below 0.50 mg/kg were processed. Fusarium Tri5 DNA content in rye was highly associated with malt DON levels (r = 0.83) in a small subset of samples (n = 55). The impact of Fusarium infection on malt quality was demonstrated by the significant correlations between malt DON levels and wort viscosity, β-glucan content, wort color, wort p-coumaric acid content, and total phenolic content. Additional correlations of rye Fusarium Tri5 DNA contents with malt diastatic power (DP), wort free amino nitrogen (FAN) content, and arabinoxylan content were observed.

BASIC INGREDIENTS AND THEIR ANALYSIS DURING THE FORMATION OF BEER QUALITY

The analysis and comparative description are carried out of varieties of brewing barley light malt and type 90 hops from domestic and foreign producers, as the main plant raw material that forms the quality of beer. The quality indexes of malt samples and hop pellets have been tested for compliance with applicable standards.The obtained results indicate that the varieties of barley malt are homogeneous grain mass, do not contain moldy and damaged grains, weed impurities, have a color from light yellow to gray to yellow. Ten samples of malt of various grades for beer production have been studied in terms of mass fraction of moisture (3.2–3.7%), mass fraction of extract in dry matter of fine malt (82.4–87.5%), degree (0 9–1.2%), the mass fraction of protein substances in dry matter of malt (9.1–10.1%), the Kolbach index (39.1–40.2%), the amount of nitrogenous substances (0.70–0, 74%). It has been established that the quantitative content of β-glucans significantly differs in different varieties: the minimum amount is contained in the malt Château Wien, the maximum is Pilsner Weyermann and Munich.According to the research results, it has been established that barley malt varieties have a pronounced malt aroma and sufficient fermentative activity and can serve as the base in the mash in the production of beer. It is proved that malt samples have an acceptable amount of toxic substances and radionuclides that will not affect the quality of the finished product. In assessing the quality of varieties of hop pellets by organoleptic indicators, the mass fraction of moisture and α-acids, it is established that the samples have the values of the indicators within the permissible limits. The samples have a cylindrical shape of different hues and approximately the same size; pure hop aroma, without an off-aroma; the color on the surface and at the boundary of the pellets meets the requirements of the standard. The mass fraction of α-acids is in the range from 3.0 to 12.7 %. It is revealed that bitter and aromatic hops are used for pellet production. The samples Magnym and Hallertau Perle are classified as bitter varieties. Hop pellets of the varieties Premiant and Sladek are bitter and aromatic.According to the results of the determination of quality indicators, the following ones have been identified as the best: malt – Munich, Pilsner, Carabohemian, hop pellets – Bramling Cross, Mandarina Bavaria and Magnym. The proposed varieties of malt and hops allow obtaining beer with high organoleptic characteristics, colloidal stability and expand the range of the industry by creating new varieties to meet the needs of the consumer.

Improved Method for Measuring Lipoxygenase Activity in Barley and Malt

ABSTRACTFor the lipoxygenase (LOX) activity assay, we dissolved the substrate linoleic acid in dimethyl sulfoxide (DMSO) rather than the usual 1% Tween 20. Activity curves with LOXSoybean were established and nine measurements within more than a month showed a standard deviation of the linear slopes of 4.8%. LOX activities in barley and the corresponding malt samples were followed at 10 min time-points for one hour. The activities during the time-course had the tendency to decrease at the end of the extraction time. LOX activity was then converted with the use of a LOXSoybean standard curve into absolute amounts of LOX (LOXeq), assuming the same specific activities for LOX from soybean and the ones from barley and malt, respectively. Furthermore, the protein amounts of all the extracts were determined and, finally, with the LOXeq content and the protein amount, the data were expressed in µg LOXeq/mg protein. The values of the barley samples ranged from 10.7 to 18.2 µg LOXeq/mg protein and the malt samples from 1.1 to 2.5 µg LOXeq/mg protein. As expected, the amount of LOX in malt was over 80% less, than the amount in barley.

Antioxidant Capacity and Total Phenol Content in Hop and Malt Commercial Samples

AbstractThe antioxidant properties of commercial hops and malted barley were evaluated by electroanalytical methods and compared with spectrophotometric methods. Hop group showed better antioxidant capacity and total phenols content (TPC) values than malt group. The highest electrochemical Index (EI) was observed for HCO hop sample. Electrochemical Index (EI) showed a good Pearson correlation with ABTS (2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid)), DPPH (2,2‐diphenyl‐1‐picrylhydrazyl), and TPC, being of 0.85, 0.77 and 0.86 respectively for hop samples. While for the malt samples were 0.96, 0.69 and 0.49, respectively. The samples were compared to each other within each group and statistical differences can be observed, p&lt;0.05. Therefore, the electroanalytical tools showed to be practical and easy to evaluate the antioxidant properties of hop and malt samples. The results may contribute to the selection of raw material for brewing and therefore with the quality of one of beverage one most consumed around the world.