Potable Spirits Research Articles

125thAnniversary Review: Barley research in relation to Scotch whisky production: a journey to new frontiers

Human experience with barley has been well established for several millennia and barley research has been fundamental to our understanding of raw materials for malting, brewing and distilling. Distillers have long been indebted to malting, brewing and distilling researchers for information on barley (and malt) relevant to their operations. Originally distilling barley research was focussed on the parameters defining barley quality and plant performance, but it has developed to further our understanding of the properties and genetics of barley and malt. Through the years, several strategic milestones can be identified showing a progression of related research themes, culminating in our current state of knowledge of barley. These include the development of the fermentability method, together with the biochemistry and enzymology underlying starch and cell wall hydrolysis, which resulted in a greater understanding of processing properties and subsequent improvements in performance. Ethyl carbamate is a barley-derived carcinogen present in a range of potable spirits, which has been a concern for distillers; the identification of the genetic marker for the barley precursor epiheterodendrin laid the foundations for the application of modern (non-GMO) genetics to developing improved barley varieties, which will benefit the whole supply chain. Together these approaches underline the mutual interdependence of applied research and genetic approaches in achieving substantial advances in our knowledge. Copyright © 2015 The Institute of Brewing & Distilling

Microfluidic devices for optical determination of ethanol concentration

A microfluidic device with integrated optical fibres has been used for the determination of the ethanol concentration in wines and beverages. Two cleaved optical fibres were placed face to face perpendicularly to the microfluidic channel with a gap comparable to the width of the channel. They are respectively connected to a light source and a spectrometer for the optical detection. Absorption spectra of a mixture of potassium dichromate plus sulphuric acid and diluted ethanol have been studied as a function of ethanol content, showing a linear dependence between the measured absorbance and the ethanol concentration. Then, several commercial potable spirits and wines have been used to demonstrate the applicability of the proposal microfluidic method.

ETHYL CARBAMATE FORMATION IN THE PRODUCTION OF POT STILL WHISKY

The formation and distribution of ethyl carbamate (urethane) during pot still distillation was investigated. Formation only occurred if the distillation was carried out in the presence of copper. Removal or chelation of dissolved or suspended copper prevented ethyl carbamate formation. When copper was present, during and subsequent to distillation, formation of ethyl carbamate was time-dependent. The degree of formation was maximised between pH 4 and 6. During the second or low wines distillation only 1–2 per cent of the total available ethyl carbamate was collected with the potable spirit fraction. The remainder was distributed between the feints (15 per cent) and the spent lees (84 per cent).

Protein products from yeast.

tiiornyces genes in S. cerevisiue (J. M. Beaumont, C. Merrill, S. A. Findlayson, J. R. Johnston & D. R. Berry, unpublished work). Brewing strains containing four DEXI, DEX2 and STA3 genes have been constructed and found to ferment worts to a much lower gravity than normal brewing strains (Russell & Stewart, 1986), but do not have any debranching activity. Faster fermentations have been obtained using diastatic strains which were selected for catabolite derepression using 2-deoxyglucose resistance. Progress is still being made in the genetic analysis of brewing and distilling yeasts. Recently improved sporulation rates have been obtained from brewing strains using improved sporulation media (Bilinski et al., 1986) and the genetics of aneuploid and tetraploid distilling strains have been analysed by the hybridization of restriction fragments with selected gene probes (Keiding, 1985). In deciding a strategy for cloning amylolytic genes into yeasts to be used for fermenting distilled beverages it is necessary to consider: ( i ) the enzyme activity required; (ii) the most appropriate donor organism, bearing in mind consumer acceptability; (iii) selection of an appropriate gene banking technique; (iv) selection of a procedure for introducing the amylase gene into the distilling strain which does not introduce other undesirable characteristics; and (v) selection of an appropriate expression system providing the level of expression required. These requirements are probably more difficult to satisfy when the product is a potable spirit than when it is industrial or fuel alcohol. Berry, D. R. ( I 984) l’rog. Ind. Microhiol. 19, 190-243 Berry, D. R. & Chamberlain, H. (1986) ASRC’J. 44, 52-56 Bilinski, C. A,, Russell, I. & Stewart. G. G. ( I 986) J . Itist. Rrcw 92,

Major volatiles in Sri Lankan arrack, a palm wine distillate

SummaryArrack is a potable spirit produced in Sri Lanka by fermenting sap usually obtained from the coconut palm. In this study the major volatiles present in several commercial samples of arrack are found to be similar to those in other potable spirits although their individual concentrations differ. The variation between brands is attributed to differences in the quality of the fermented toddy used. This is thought to result from the uncontrolled and mixed nature of the fermentation. Ethyl lactate was found in all samples analysed and it is thought that production of this ester is a characteristic feature of mixed lacticalcoholic fermentations.

An automatic densimeter system for themeasurement of the alcoholic strengthof potable spirits

its density. Automation of the first three steps is difficult, samples vary greatly in viscosity and the more viscous liquors would not pass through the passageways of most dispensing arrangements. Also, by using a constant temperature bath and a bank of four or more stills, one operator can produce distillates ready for density measurement at a rate of about 20 per hour, which would be hard to match with an automatic system.

Gas chromatographic column for the rapid determination of congeners in potable spirits

The determination of minor components, including fatty acids, in potable spirits has been accomplished by using acid-washed (AW) Carbopack B, an example of graphitized carbon black, modified with PEG 20M. Quantitative data for selected compounds show that good precision can be obtained even at the level of a few parts per million. The determination of minor components in a commercial sample of Scotch whisky was carried out by using AW Carbopack B modified with 6.6% of PEG 20M. Components present in concentrations of about 0.5 ppm can be determined with a precision of about 30%. An additional column packing (AW Carbopack B + 3.35% of PEG 20M) was used for determining those few components of minor interest which cannot be separated by the former column packing.

Discrimination between synthetic and natural ethyl alcohol in spirits and fortified wines

SummarySynthetic alcohol from petrochemical sources has a low 14C content as compared to fermentation alcohol produced from contemporary carbohydrates. The 14C contents of seventy‐eight samples of potable spirits and fortified wines are reported and discussed in relation to their usefulness in detecting the use of synthetic alcohol. The importance of correcting for the effects of congeners during the 14C‐assay is discussed.The 14C level at which the use of synthetic alcohol might be presumed will vary according to the methods employed in producing the beverage.

V The development of flavour in potable spirits

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Recent developments in the analysis of food and drink. Standardisation of methods of analysis for potable spirits

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Measures against water pollution in the fermentation industries.

The paper is a review of some current practices in the treatment and disposal of the more important fermentation industry effluents. Reference is made to the production of whisky and other potable spirits, malt, beer, vinegar, yeast, cider, antibiotics and vitamins. The most important means of treating distillery effluents is by recovering the soluble and some insoluble material in the liquid residue from the distillation of fermented wash. The process involves evaporation and drying to produce dry, nutritionally rich animal feeding materials by the sale of which the capital cost of the plant may be recovered. Condensate from the evaporation process contains organic acids and must be treated biologically before discharge to rivers, as must other watery residues from the distillery. Treatment may be on conventional mineral packed biological filters, on plastic filled towers or by an activated sludge process. Other methods of disposal of distillery wastes include complete biological treatment of the mixed effluents, disposal to land, to sea and to sewers. Discharges to sewers often attract special charges by the local authority. Burning wastes with the recovery of heat and ash is also practiced. Effluents from the malting process are easily treated biologically, whether on site at the maltings or, after discharging to sewers, at the local authority sewage works in admixture with sewage. Brewery effluents, mostly cooling and wash waters, are usually discharged to sewers, but some biological pre-treatment may be given on site, where plastic packed biological filter units are sometimes used. Vinegar factory effluents are also usually discharged to sewers and are easily treatable. The ease with which most fermentation wastes can be treated biologically has encouraged the industries concerned to ask local authorities to acknowledge the fact by suitably reducing charges for effluents treated at the sewage works. Yeast manufacturing effluents comprise residual wash, yeast washings etc., and are readily treatable biologically. Fears that yeast effluents cause slime growths in sewers are not substantiated in practice, but a case is described in which yeast wastes are piped separately from sewage to the disposal site. Cider effluents are easily treated biologically, either on site with additions of suitable nutrients, or in admixture with sewage. Antibiotics and vitamin fermentation effluents are sometimes difficult to treat biologically, but are often so treated and are sometimes acceptable in sewers. Recovery of solids from residual washes is practiced, with the production of material suitable for animal feeding. In the UK the tendency is for factories to be sited on estuaries or the sea coast where untreated effluent may be discharged

A standardization OF METHODS FOR DETERMINATION OF THE ALCOHOL CONTENT OF BEVERAGES AND DISTILLED POTABLE SPIRITS.

Article A Standardization of Methods for Determination of the Alcohol Content of Beverages and Distilled Potable Spirits was published on January 1, 1968 in the journal Pure and Applied Chemistry (volume 17, issue 2).

The proportion of 2-methylbutanol and 3-methylbutanol in some brandies and whiskies as determined by direct gas chromatography

Stationary phases suitable for the separation of 2-methylbutanol (“active” pentanol) and 3-methylbutanol (isopentanol) are discussed. The most suitable for the determination of these alcohols in potable spirits by direct injection of samples are diethyl tartrate and polyethylene glycol 200. Polyethylene glycol 200 is preferred because other congeners can be determined at the same time. With n-pentanol as an internal standard, 65 samples of cognac brandies, Scotch and other whiskies have been examined on one or other of these stationary phases. The sum of the two pentanol isomers determined separately agrees well with their determination as a single peak on polyethylene glycol 1500. The ratio of the concentrations of the isomers appears to be characteristic of the type of spirit.

The analysis and composition of potable spirits: determination of C3, C4 and C5 alcohols in whisky and brandy by direct gas chromatography

The determination of the principal C3 to C5 alcohols in potable spirits by direct gas chromatography is discussed. Application of this method to 78 samples of various types of brandy and whisky gives results indicating that the total higher-alcohol content is not characteristic of the type of spirit, but that the proportions of the alcohols to each other fall into distinct ranges typical of the particular spirituous beverage.

The determination of higher alcohols in potable spirits: comparison of colorimetric and gas-chromatographic methods

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Instability in potable spirits. III.—gin and vodka

AbstractFor good quality gin and vodka a ‘clean’ spirit is essential. Prolonged contact with a number of metals, or contamination with metallic salts, is to be avoided. There is no critical pH for the formation of a deposit as in other potable spirits. The deposit formed in vodka is calcium carbonate, but deposits of calcium and magnesium sulphate and magnesium carbonate are also possible. The solubility of calcium carbonate in different concentrations of alcohol is compared with values for Russian vodka and the effect of large concentrations of other ions is considered. The use of demineralised water is recommended for both gin and vodka. Where this is not possible, careful monitoring of softened water is essential.

Instability in potable spirits. I.—Scotch whisky

AbstractInstability in spirits is partly inherent, partly caused by contamination during maturation and partly due to bad filtration techniques. Instability occurs as deposition with metallic contamination and alteration of the pH to critical values. It is distinct from the formation of “inks”. Chill‐proofing is not sufficient in itself to provide a stable product if sufficient contamination occurs afterwards. Ion‐exchange in the H+ form removes an instability factor.

The determination of higher alcohols in whisky and other potable spirits

The determination of higher alcohols in whisky and other potable spirits

Report on Aldehydes in Whisky and Other Potable Spirits

Journal Article Report on Aldehydes in Whisky and Other Potable Spirits Get access Peter Yalaer Peter Yalaer Associate Referee Alcohol Tax Unit, Bureau of Internal Revenue, Washington, D. C Search for other works by this author on: Oxford Academic Google Scholar Journal of Association of Official Agricultural Chemists, Volume 23, Issue 2, 1 May 1940, Pages 194–198, https://doi.org/10.1093/jaoac/23.2.194 Published: 21 February 2020

Report on Aldehydes in Whiskey and Other Potable Spirits

Report on Aldehydes in Whiskey and Other Potable Spirits