COMPARISON OF DIFFERENT MALT ANALYSES

The results of applying three types of analytical mashing procedure—Institute of Brewing, European Brewery Convention, and Tepral systems—to the same malts are examined. Statistical correlations of the results are made. It is concluded that the main difference between the results of the Tepral method and the other two procedures is that the first gives much lower extracts when applied to malts which would be likely to be troublesome in the brewery, and is thus more discriminatory for these. The advantages of including sparging in an analytical method are pointed out.     

Blends of olive oil and sunflower oil: Characterisation and olive oil quantification using fatty acid composition and chemometric tools

A method capable of recognising the percentage of olive oil in a blend is required to verify whether its labelling complies with the statements set out by the Commission Regulation (EC) No. 1019/2002. In this study an analytical methodology was developed in order to define blends of olive oil and sunflower oil, which contain 50% of olive oil, compared to blends with 40% and 60% of it, respectively. Methyl esters of fatty acids were analysed by GC–FID and processed through chemometric tools (PCA, TFA, SIMCA and PLS). A strong differentiation of blends according to the amount of olive oil contained and a quantification model with a standard error of prediction of 1.51% were obtained. As this issue represents a significant analytical challenge, variability associated with the fatty acid composition of olive oil was first studied.     

MALTING AND BREWING WITH BARLEYS HAVING BLUE ALEURONES

Blue aleurones in barley are associated with elevated levels of polyphenolic materials such as anthocyanins and anthocyanidins. A rapid method has been developed for assessing the anthocyanin content of barleys, malts and worts. Malts were prepared from a range of barleys, some of which had intensely blue aleurones, while others were only slightly blue or showed no visible pigmentation. The malting quality of barley was not affected by aleurone colour and ales and lagers of sound flavour as well as acceptable analytical parameters were brewed from malts having pronounced blue aleurones. In some cases sweet worts prepared from blue aleurone malts had a slight pinkish tinge, but this disappeared during wort boiling, and beer colours were normal. Levels of anthocyanins in barley correlated with those in malt and in wort. However, the concentration of anthocyanins was unrelated to the amount of anthocyanogens or total polyphenols. High anthocyanin levels in either barley or beer had no deleterious effects on beer flavour or the rate of haze development.     

Properties of Three Sorghum Cultivars Used for the Production of Bili‐Bili Beverage in Northern Cameroon

The malting characteristics of sorghum malts produced locally in Cameroon for Bili‐Bili brewing were compared with those of malts produced in a laboratory. The analytical values of both malts were similar but the brewing potential of the laboratory malts were marginally better than those of the locally produced malts. Of the three cultivars examined, Madjeru had the lowest levels of β‐amylase, maltose levels and fermentability. The worts of the Madjeru filtered the slowest of the three malts. During malting β‐glucanase developed rapidly and development was temperature‐dependent.     

THE EFFECT OF INCREASED STEEPING TEMPERATURE ON MALT PROPERTIES

Steeping barley at 30°C instead of 16°C can reduce malting time by 24 hours. The malts produced have normal analytical values but the mashes filter slowly and the malts would be expected to give poor wort separation in a brewery. These run-off problems probably result mainly from starch-protein interactions.     

Monte Carlo simulation based prediction of blended oil composition containing mustard,rapeseed and soybean oil

High erucic acid rapeseed and mustard seed (HEARM) oils are popular cooking oil in various southeast Asian countries (e.g. Nepal, India, Bangladesh) due to the preference of the local consumer for its strong pungency. Low erucic acid rapeseed (LEAR) oil having lower pungency is frequently mixed with the pungent HEARM oil to increase its sensory appeal to the local consumer. Moreover, these oils are also prone to be adulterated with the cheaper oil available in the local market like soybean oil for economical reasons. In order to detect this fraud in a quick and easy manner, a Monte Carlo simulation based approach was developed for the estimation of blend composition using only the fatty acid composition of the sample. The limits of detection (LODs) of soybean oil in HEARM oil and LEAR oil were 14% and 13%, respectively. The LODs of LEAR oil in HEARM oil and soybean oil were 11 and 9%, respectively. Similarly, the LODs of HEARM oil in LEAR oil and soybean oil were 9% and 3%, respectively. The prediction from the developed method was evaluated both in real oil blends (prepared in the laboratory) and in theoretically simulated blends. The method was applied on forty-nine samples (labeled as mustard/rapeseed oil) collected from the Nepalese market. Among them, twenty-seven samples were found to be adulterated with soybean oil. The predicted adulteration was further supported by their δ-tocopherol content and trans fatty acid content, as an indicator for the adulteration with refined oil. The developed Monte Carlo simulation method is based on a single analytical run of determining the fatty acid composition of the suspected oil blend and thus useful for a quick segregation of samples in routine analysis.     

Determination of biodiesel blending percentages using natural abundance radiocarbon analysis: testing the accuracy of retail biodiesel blends

Blends of biodiesel and petrodiesel are being used increasingly worldwide. Due to several factors, inaccurate blending of these two mixtures can occur. To test the accuracy of biodiesel blending, we developed and validated a radiocarbon-based method and then analyzed a variety of retail biodiesel blends. Error propagation analysis demonstrated that this method calculates absolute blend content with +/- 1% accuracy, even when real-world variability in the component biodiesel and petrodiesel sources is taken into account. We independently confirmed this accuracy using known endmembers and prepared mixtures. This is the only published method that directly quantifies the carbon of recent biological origin in biodiesel blends. Consequently, it robustly handles realistic chemical variability in biological source materials and provides unequivocal apportionment of renewable versus nonrenewable carbon in a sample fuel blend. Analysis of retail biodiesel blends acquired in 2006 in the United States revealed that inaccurate blending happens frequently. Only one out of ten retail samples passed the specifications that the United States Department of Defense requires for blends that are 20% biodiesel (v/v; referred to as B20).     

35—IMPROVEMENT OF THE NATURAL FLAME-RESISTANCE OF WOOL. PART IV: WOOL-RICH BLENDS WITH POLYESTER FIBRE AND NYLON

Wool-polyester-fibre and particularly wool-nylon blends show a significant negative deviation of limiting-oxygen index (LOI) from the average, calculated values. This is probably due to the higher heat of combustion and lower LOI of polyester fibre and particularly of nylon when compared with wool.

Consequently, wool-rich blends with nylon are more difficult to flame-resist-treat with metal complexes than wool-polyester-fibre blends. In the former blend, at least 75% flame-resistant wool and in the latter blend 60–90% flame-resistant wool has to be present to enable flame-resistant wool-rich blends to be obtained, the exact amount depending on the fabric construction. The hexafluorozirconate treatment is effective on blends containing at least 85% wool, whereas zirconium-tungsten complexes have to be applied for blends with lower wool contents.     

DIFFERENTIATION OF PEATED AND UNPEATED DISTILLING MALT BY G.L.C. ANALYSIS

Difficulty may occur in trying to distinguish unpeated malt from lightly peated malt by colourimetric analytical methods. This paper outlines a prospective method using gas chromatography following a selective extraction of volatiles from the malt. This method is discussed in relation to previous published methods used in the identification of peated export malts.     

THE INSTITUTE OF BREWING ANALYSIS COMMITTEE REVISED METHODS OF EXTRACT DETERMINATION

Following a Brewer's Society request to consider a change from a standard Miag Disc Mill setting of 0·5 mm to one of 0·7 mm the Analysis Committee has re-evaluated the determination of hot water extract. It is recommended that from 1st December 1979–1. A Miag Disc Mill setting of 0·7 mm be adopted for grinding malt for the determination of hot water extract. 2. Where an estimate of the fine/coarse grind hot water extract difference is required, mill settings of 0·2 mm and 0·7 mm respectively should be used. The reproducibility of this procedure is adequate to separate malts into classes with high and low values but analytical tolerances cannot be recommended for commercial transactions. Revised methods for setting the Miag Disc Mill and for determining the hot water extract of fine and coarse ground malts are given in Appendix I. It is proposed that all mashes should be made in stainless steel beakers, the use of the standard brewers' mash flask being limited to making the mash to the correct volume at the end of the determination. It is recommended that, from 1st December 1979, the 0·7 mm Miag Disc Mill setting should replace also the 0·5 mm setting in all Recommended Methods for coloured malts, dark malts, roasted barley and unmalted grain. It is further recommended that from 1st December 1979 all specific gravity determinations for laboratory extracts of malt, coloured malt, dark malt, roasted barley, unmalted grain, sugars, syrup, caramel and spent grains should be made at 20°C.     

PREDICTION OF THE LAUTERING PERFORMANCE OF MALT

The lautering performance of malt in a laboratory column can be predicted from the results of a series of simple analytical estimations. For normal commercial malts, prediction of lautering rates requires measurement of particle size after passage through a roller mill, combined with results from a simple sedimentation test. For poorly-modified malts a laboratory scale mashing operation is additionally required. This allows estimation of the volume of fine particles in the exhausted mash bed and a measurement of wort viscosity.     

藜麦芽多肽制备及其应用研究

该研究以白藜麦为原料,通过人工调控藜麦萌芽的培养条件,促进藜麦萌发过程中蛋白质向多肽的转变,制备富含多肽的藜麦芽(多肽藜麦芽)。考察浸泡温度、浸泡时间、培养时间3个因素对藜麦芽中多肽富集的影响,在单因素的基础上采用正交试验方法对藜麦芽培养条件进行优化,得出最佳培养条件为浸泡温度25℃,浸泡时间4 h,培养时间48 h,在此条件下,藜麦芽中多肽含量为(12.4±1.13)mg/g。将培养得到的多肽藜麦芽进行低温打浆处理,以冷冻干燥技术得到多肽藜麦芽粉,所得多肽藜麦芽粉呈乳白色,易溶解,在饮料等食品当中可作为营养型添加剂加入使用。     

THE INFLUENCE OF MASHING CONDITIONS ON WORT AND BEER QUALITY

From a comparison of the performance of ale and lager malts mashed by constant temperature infusion, by temperature programmed infusion, and by decoction procedures it emerges that malt modification and the pattern of kilning are as important in determining the composition of wort as are the mashing conditions. Worts with appropriate levels of amino and total nitrogen and of fermentable sugars may be obtained by selecting lightly-dried well-modified malts and mashing with a constant temperature infusion rather than by using less modified malt in conjunction with more complex mashing programmes. Ale malts yield worts of lower pH which is reflected in a slight reduction in hop utilization. Head retention is improved by the use of undermodified malts but colloidal stability is improved when well-modified malts are used. In the case of well-modified malts a high final curing temperature is not a prerequisite for achieving good colloidal stability in beer.     

THE MEASUREMENT OF DIMETHYL SULPHIDE PRECURSOR IN MALTS,ADJUNCTS, WORTS AND BEERS

Dimethyl sulphide in beer originates from a precursor in the malt. A method is described for the measurement of this precursor in brewing raw materials, wort and beer. The precursor levels in various green malts, kilned malts, and adjuncts are given. Excess methionine inhibits precursor uptake by yeast during fermentation. Residual precursor is still present in some commercial bottled beers.     

The effect of germination and kilning on the cyanogenic potential,amylase and alcohol levels of sorghum malts used for burukutu production

Grain sorghum of the red and white varieties was malted by steeping in water for 18 h, germinated over 5 days and kilned at 50 °C. The malts were analysed for amylase activities and cyanogenic potential and used to produce burukutu, an alcoholic beverage. The alcohol content of the burukutu was recovered by distillation and determined by the refractive index method. α‐Amylase activity peaked on malting day 3 and was higher in the white malts. β‐Amylase activity peaked on day 3 in the red malts and on day 4 in the white malts, but was higher in the red malts. Dhurrinase activity was highest on malting day 4, with a higher activity in the red malts. Kilning at 50 °C reduced the activities of these enzymes. The dhurrin content increased during germination and was consistently higher in the white malts, in which there was evidence of dhurrin mobilisation. In the red malts the dhurrin content increased during germination but decreased progressively after kilning; evidence of dhurrin mobilisation was apparent as from malting day 4. Burukutu produced from the red malts gave higher alcohol contents than that from the white malts. Maximum alcohol yields were obtained on malting day 3 in the red malts and on day 5 in the white malts. © 2000 Society of Chemical Industry     

丝素与聚氨酯共混膜的热压条件探讨

采用热压法,对丝素粉体与水性聚氨酯的共混物进行热压处理,并研究了丝素粉体与水性聚氨酯的共混物在不同时间和不同压力的热压条件下制得共混膜的性能.结果表明:热压法制得的共混膜结构致密,手感柔软光滑,透明度较高;当热压压力为35 MPa,热压时间为10 min时,得到的共混膜断裂强度和杨氏模量最高,断裂伸长率最低,吸水性也较...     

STUDIES ON THE MALTING POTENTIAL OF BARLEY AND MALT WITH THE FALLING NUMBER APPARATUS

The Falling Number Apparatus was investigated as a possible technique for the identification of barleys and malts with high malting potential. The FN method was not as accurate or as rapid as that based on Pearling Resistance. The effect of increasing times of malting on the Falling Times of malts was also investigated to determine whether the progress of malting could be monitored, as was the effect of different cultivars. Testing under conditions inhibitory to amylolytic activity was found necessary to give useful results. Some comparisons with the Rapid Visco Analyser (RVA) are presented.     

Foam inhibitors from specialty malts

Although there are product‐to‐product differences, the majority of the crystal and caramel malts tested have been shown to have a net destabilizing impact on foam. A foaming test using a model beer has been developed to quantify the magnitude of this inhibitory effect. Lipid analysis using thin‐layer chromatography reveals that there are elevated levels of triglycerides in problematic malts. There also appear to be oxidized lipids in the specialty malts, probably produced in the heating stage of malt production with higher levels in more intensely heated products. However some specialty malts, such as black malt, while containing such foam‐negative entities, do display superior foaming properties, probably because they develop even more powerful foam‐positive components in the severe heating events. Copyright © 2014 The Institute of Brewing & Distilling     

Optimization of blended wine quality through maximization of consumer liking

A mixture design was used to optimize blended Vitis vinifera wines (Cabernet Sauvignon, Merlot and Zinfandel) for consumer acceptability. Consumer overall liking values were modeled within an augmented simplex centroid mixture design to determine areas of desirability for each consumer. Two major segments of consumers were identified, with membership mainly dependent upon responses to Zinfandel. Samples were less polarizing when the wines were blended as opposed to remaining as single wines. Three optimized blends were created: for all consumers, segment 1 and segment 2. A subsequent consumer study indicated that optimized blends for each segment were not significantly different from the other wines. However, segment 2 consumers preferred the segment 2 blend to the wine blend optimized across all consumers. The optimized blend across all consumers was the least liked for each segment. Identifying consumer segments can help better optimize products for successful entry into the marketplace. Optimizing a product within a mixture design environment is a useful, efficient technique to understand ingredient interactions and how they affect overall consumer acceptance.     

ACCEPTABILITY OF BEEF PATTIES EXTENDED WITH PORK AND/OR TEXTURED SOY PROTEIN1

Four beef or beef/pork ground meat blends were extended with textured soy protein (TSP) at 0, 10, 20 and 30% levels. Ground beef/pork/textured soy protein (TSP) patties with 30% TSP were rated lowest by consumers for raw color and appearance and overall cooked appearance. A beef (50%) and pork (30%) blend containing no TSP was rated highest by consumers for tenderness, flavor and overall desirability and higher by a trained sensory panel for flavor and overall desirability than blends containing TSP. Overall desirability ratings for visual and palatability characteristics of beef/pork meat patties were higher than for beef/pork/TSP blends. Results indicated a distinct advantage for palatability of the beef/pork blend as compared to beef/pork/TSP combinations.