Gary Spedding - Academia.edu (original) (raw)
Papers by Gary Spedding
Abstract This chapter is presented in two parts. Part 1 covers those microorganisms (bacteria, mo... more Abstract This chapter is presented in two parts. Part 1 covers those microorganisms (bacteria, molds, and wild yeasts) whose metabolism conveys upon beer either unwanted (atypical) flavors leading to spoilage of product or those that might be used to attain specific flavor profiles and unique brand beer styles. Those flavors are then explored in detail with respect to descriptors, typical levels found in beer (naturally or via microbiological metabolic activities), and their sensory detection threshold values. This information is used for their sensory assessment in beer wort, beer, and brewing raw materials. Part 2 then describes the sensory programs that can be implemented to study beer flavor profiles and to help ensure the safety, consistency, and overall quality of beers released for consumption.
Brewing Materials and Processes, 2016
Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the... more Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the form of malt-based alcoholic beverages has grown with the rise of civilization. Brewers and chemists have worked to measure the content of ethanol, or alcohol strength, in brewer's fermenting wort and finished beer for at least 180 years. As a key parameter, it is required to determine brewhouse efficiency, inform consumers of alcohol levels for caloric information and responsibility purposes, as well as act as a guide for taxation implemented by regulatory agencies. A brief review of the multitude of methods which have been used to determine alcohol content is presented, followed by a more in depth look at how brewers today determine, with suitable accuracy and precision, the alcohol content of their beers.
Oxford University Press eBooks, 1990
Elsevier eBooks, 2016
Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the... more Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the form of malt-based alcoholic beverages has grown with the rise of civilization. Brewers and chemists have worked to measure the content of ethanol, or alcohol strength, in brewer's fermenting wort and finished beer for at least 180 years. As a key parameter, it is required to determine brewhouse efficiency, inform consumers of alcohol levels for caloric information and responsibility purposes, as well as act as a guide for taxation implemented by regulatory agencies. A brief review of the multitude of methods which have been used to determine alcohol content is presented, followed by a more in depth look at how brewers today determine, with suitable accuracy and precision, the alcohol content of their beers.
The Journal of Distilling Science, 2021
The Journal of Distilling Science is the first truly dedicated organ for the publication of peer ... more The Journal of Distilling Science is the first truly dedicated organ for the publication of peer reviewed original works and reviews of relevance to the technological, scientific and production aspects of quality distilled spirits. An official publication associated with the Society of Distilling Scientists and Technologists. The inaugural issue was published in December 2021
Alcoholic strength is the term used to denote the measure of the amount of ethyl alcohol (ethanol... more Alcoholic strength is the term used to denote the measure of the amount of ethyl alcohol (ethanol) in solutions such as beer, cider, kombucha, malt-beverages, RTD cocktail mixes, wines and spirits/liqueurs. It may be reported as percent by mass of solution (% weight/weight – w/w or mass/mass m/m) or as percent by volume (% volume/volume – v/v). These values are expressed at either 60 °F (15.56 °C) or at 20 °C (68 °F) depending on country, regulatory authority or other local requirements.
The distilled beverage industry is creating new products at a rapid pace; at the same time it is ... more The distilled beverage industry is creating new products at a rapid pace; at the same time it is under constant attack from counterfeiters and those who would adulterate or dilute distilled spirits and liqueurs. Recently, it has been discovered that UV-Visible spectroscopy provides a rapid and powerful tool to test the quality of distilled spirits and to detect adulterated and counterfeit products1-5. Distilled spirits are broadly classified as white and aged spirits. As spirits age in the wood they pick up sugars, tannins, other complex biochemical components and color and undergo considerable chemical reactions. This changes the profile of the spirit in complex and still largely unresolved ways. In addition, for some spirit designations coloring, sugar, citric acid and botanicals may be present. Changes in aging and the addition of components may be followed or detected through uvvisible scanning of samples. The SPECTROstar Nano microplate reader can rapidly and precisely measure ...
The ribosomal protein S4 is a translational repressor that binds to a complex mRNA pseudoknot str... more The ribosomal protein S4 is a translational repressor that binds to a complex mRNA pseudoknot structure containing the ribosome binding site for the first gene of the a operon. Either 30S subunits or S4 protein bound to the mRNA causes Moloney murine leukemia virus reverse transcriptase to pause near the 3' terminus of the pseudoknot. There is no competition between subunits and S4 for mRNA binding. The kinetics of forming S4-30S-mRNA complexes are biphasic, and the fraction of mRNA molecules reacting more rapidly decreases as the temperature is increased from 30°C to 40°C. The complex cannot be detected with mRNA mutants that cannot be repressed. We have previously shown similar kinetic behavior for the formation of tRNAIet initiation complexes with tRNAf et, 30S subunits, and mRNA, except that the fraction reacting rapidly increases when the temperature is increased over the same 30-40°C range. Thus the two sets of experiments show that there are two forms of 30S-mRNA complexe...
Journal of the American Society of Brewing Chemists, 2013
This review covers what is, arguably, the world's most widely used food industry-related assa... more This review covers what is, arguably, the world's most widely used food industry-related assay, the ninhydrin reaction, for the determination of the free amino nitrogen content of biological materials, including beverages and foods. This assay, for application to beer and wine samples, was adapted for use in a multi-well format and demonstrated the potential to scale down and run more multi-well tests in brewing quality control testing laboratories. Scaling down brewery laboratory tests reduces demands for expensive reagents, limits waste, and makes for simpler, less expensive disposal, while also giving a faster turnaround of results for many assays. In redefining the ninhydrin free amino nitrogen assay for use with modern instruments, we rediscovered the most efficient reagents and optimal conditions for application of this test in the contemporary brewing laboratory. Six critical parameters for ninhydrin reactions (buffer composition, incubation time, temperature, pH, assay volume, and reducing agent) have been reassessed with a new microwell assay combining all of them, now providing high precision and sensitivity. Finally, new reduced volume and microwell-based FAN assay formats should prove useful to many brewing, enology, distilling, and food laboratories for the routine determination of free or total useable nitrogen, and for further refinement and optimization of this important assay.
BDASLLC WPSP, 2021
The complex microbiome, and metabolically complex fermentation system or "engine" that produces t... more The complex microbiome, and metabolically complex fermentation system or "engine" that produces the beverage known as Kombucha is considered here. With some of the most recent publications dealing with both vinegar (acetic acid) and kombucha production briefly outlined and cited. Kombucha has been produced for 1000's of years, yet still so little is known about it as a complex milieu of living microorganisms and their metabolic products. Acetic acid or a distinct vinegary bite, delivered from drinking kombucha, is considered both necessary and quite sufficient to appeal to many appetites. But where does the vinegar come from? This article delves a little into the details of the acetic acid bacteria that result in such acetic acid (vinegar) production, and with their interplay with the final ethanol levels that are also noted in both non-alcoholic and alcoholic versions of this beverage. These two related biomolecules causing concern over the stable quality production of kombucha.
BDASLLCWPSPNo6Kombucha Update Review, 2021
The ecologically complexmicrobiologically-based, and metabolically complex biochemical beverage, ... more The ecologically complexmicrobiologically-based, and metabolically complex biochemical beverage, Kombucha has become a multi-million-dollar drinks industry business and yet still fraught with much controversy. Are the non-alcoholic versions, below (in the US) 0.5% alcohol by volume (ABV)-expressed at 20 °C? Canada allowing 1% ABV by law for the non-alcoholic versions. Earlier literature did not go into detail about alcohol and, while later academic publications have touched upon this, there is much to be researched on this controversial topic. As presented here, the complex interplay of microorganisms is still little understood at the molecular biochemical level. We need to go way deeper, and to better educate those who believe they can control this massive collection of microorganisms. New literature may lead the way if it is accessible by current day brewers.
Journal of AOAC International, 2016
Abstract This chapter is presented in two parts. Part 1 covers those microorganisms (bacteria, mo... more Abstract This chapter is presented in two parts. Part 1 covers those microorganisms (bacteria, molds, and wild yeasts) whose metabolism conveys upon beer either unwanted (atypical) flavors leading to spoilage of product or those that might be used to attain specific flavor profiles and unique brand beer styles. Those flavors are then explored in detail with respect to descriptors, typical levels found in beer (naturally or via microbiological metabolic activities), and their sensory detection threshold values. This information is used for their sensory assessment in beer wort, beer, and brewing raw materials. Part 2 then describes the sensory programs that can be implemented to study beer flavor profiles and to help ensure the safety, consistency, and overall quality of beers released for consumption.
Brewing Materials and Processes, 2016
Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the... more Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the form of malt-based alcoholic beverages has grown with the rise of civilization. Brewers and chemists have worked to measure the content of ethanol, or alcohol strength, in brewer's fermenting wort and finished beer for at least 180 years. As a key parameter, it is required to determine brewhouse efficiency, inform consumers of alcohol levels for caloric information and responsibility purposes, as well as act as a guide for taxation implemented by regulatory agencies. A brief review of the multitude of methods which have been used to determine alcohol content is presented, followed by a more in depth look at how brewers today determine, with suitable accuracy and precision, the alcohol content of their beers.
Oxford University Press eBooks, 1990
Elsevier eBooks, 2016
Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the... more Ethyl alcohol (ethanol) is a key component of beer. The use of alcohol and its consumption in the form of malt-based alcoholic beverages has grown with the rise of civilization. Brewers and chemists have worked to measure the content of ethanol, or alcohol strength, in brewer's fermenting wort and finished beer for at least 180 years. As a key parameter, it is required to determine brewhouse efficiency, inform consumers of alcohol levels for caloric information and responsibility purposes, as well as act as a guide for taxation implemented by regulatory agencies. A brief review of the multitude of methods which have been used to determine alcohol content is presented, followed by a more in depth look at how brewers today determine, with suitable accuracy and precision, the alcohol content of their beers.
The Journal of Distilling Science, 2021
The Journal of Distilling Science is the first truly dedicated organ for the publication of peer ... more The Journal of Distilling Science is the first truly dedicated organ for the publication of peer reviewed original works and reviews of relevance to the technological, scientific and production aspects of quality distilled spirits. An official publication associated with the Society of Distilling Scientists and Technologists. The inaugural issue was published in December 2021
Alcoholic strength is the term used to denote the measure of the amount of ethyl alcohol (ethanol... more Alcoholic strength is the term used to denote the measure of the amount of ethyl alcohol (ethanol) in solutions such as beer, cider, kombucha, malt-beverages, RTD cocktail mixes, wines and spirits/liqueurs. It may be reported as percent by mass of solution (% weight/weight – w/w or mass/mass m/m) or as percent by volume (% volume/volume – v/v). These values are expressed at either 60 °F (15.56 °C) or at 20 °C (68 °F) depending on country, regulatory authority or other local requirements.
The distilled beverage industry is creating new products at a rapid pace; at the same time it is ... more The distilled beverage industry is creating new products at a rapid pace; at the same time it is under constant attack from counterfeiters and those who would adulterate or dilute distilled spirits and liqueurs. Recently, it has been discovered that UV-Visible spectroscopy provides a rapid and powerful tool to test the quality of distilled spirits and to detect adulterated and counterfeit products1-5. Distilled spirits are broadly classified as white and aged spirits. As spirits age in the wood they pick up sugars, tannins, other complex biochemical components and color and undergo considerable chemical reactions. This changes the profile of the spirit in complex and still largely unresolved ways. In addition, for some spirit designations coloring, sugar, citric acid and botanicals may be present. Changes in aging and the addition of components may be followed or detected through uvvisible scanning of samples. The SPECTROstar Nano microplate reader can rapidly and precisely measure ...
The ribosomal protein S4 is a translational repressor that binds to a complex mRNA pseudoknot str... more The ribosomal protein S4 is a translational repressor that binds to a complex mRNA pseudoknot structure containing the ribosome binding site for the first gene of the a operon. Either 30S subunits or S4 protein bound to the mRNA causes Moloney murine leukemia virus reverse transcriptase to pause near the 3' terminus of the pseudoknot. There is no competition between subunits and S4 for mRNA binding. The kinetics of forming S4-30S-mRNA complexes are biphasic, and the fraction of mRNA molecules reacting more rapidly decreases as the temperature is increased from 30°C to 40°C. The complex cannot be detected with mRNA mutants that cannot be repressed. We have previously shown similar kinetic behavior for the formation of tRNAIet initiation complexes with tRNAf et, 30S subunits, and mRNA, except that the fraction reacting rapidly increases when the temperature is increased over the same 30-40°C range. Thus the two sets of experiments show that there are two forms of 30S-mRNA complexe...
Journal of the American Society of Brewing Chemists, 2013
This review covers what is, arguably, the world's most widely used food industry-related assa... more This review covers what is, arguably, the world's most widely used food industry-related assay, the ninhydrin reaction, for the determination of the free amino nitrogen content of biological materials, including beverages and foods. This assay, for application to beer and wine samples, was adapted for use in a multi-well format and demonstrated the potential to scale down and run more multi-well tests in brewing quality control testing laboratories. Scaling down brewery laboratory tests reduces demands for expensive reagents, limits waste, and makes for simpler, less expensive disposal, while also giving a faster turnaround of results for many assays. In redefining the ninhydrin free amino nitrogen assay for use with modern instruments, we rediscovered the most efficient reagents and optimal conditions for application of this test in the contemporary brewing laboratory. Six critical parameters for ninhydrin reactions (buffer composition, incubation time, temperature, pH, assay volume, and reducing agent) have been reassessed with a new microwell assay combining all of them, now providing high precision and sensitivity. Finally, new reduced volume and microwell-based FAN assay formats should prove useful to many brewing, enology, distilling, and food laboratories for the routine determination of free or total useable nitrogen, and for further refinement and optimization of this important assay.
BDASLLC WPSP, 2021
The complex microbiome, and metabolically complex fermentation system or "engine" that produces t... more The complex microbiome, and metabolically complex fermentation system or "engine" that produces the beverage known as Kombucha is considered here. With some of the most recent publications dealing with both vinegar (acetic acid) and kombucha production briefly outlined and cited. Kombucha has been produced for 1000's of years, yet still so little is known about it as a complex milieu of living microorganisms and their metabolic products. Acetic acid or a distinct vinegary bite, delivered from drinking kombucha, is considered both necessary and quite sufficient to appeal to many appetites. But where does the vinegar come from? This article delves a little into the details of the acetic acid bacteria that result in such acetic acid (vinegar) production, and with their interplay with the final ethanol levels that are also noted in both non-alcoholic and alcoholic versions of this beverage. These two related biomolecules causing concern over the stable quality production of kombucha.
BDASLLCWPSPNo6Kombucha Update Review, 2021
The ecologically complexmicrobiologically-based, and metabolically complex biochemical beverage, ... more The ecologically complexmicrobiologically-based, and metabolically complex biochemical beverage, Kombucha has become a multi-million-dollar drinks industry business and yet still fraught with much controversy. Are the non-alcoholic versions, below (in the US) 0.5% alcohol by volume (ABV)-expressed at 20 °C? Canada allowing 1% ABV by law for the non-alcoholic versions. Earlier literature did not go into detail about alcohol and, while later academic publications have touched upon this, there is much to be researched on this controversial topic. As presented here, the complex interplay of microorganisms is still little understood at the molecular biochemical level. We need to go way deeper, and to better educate those who believe they can control this massive collection of microorganisms. New literature may lead the way if it is accessible by current day brewers.
Journal of AOAC International, 2016