00:16 Theory of the Analytical Procedure
01:08 Kit Content
01:37 Reagent Preparation
04:44 Milling of Samples
05:40 Weighing of Malt Samples & Extraction of Alpha Amylase
09:12 Weighing of Wheat & Barley Flour & Extraction of Alpha Amylase
11:31 Extraction/Dilution of Microbial Enzyme preparations
14:16 Assay Procedure
100 assays per kit
Prices exclude VAT
Available for shipping
|100 assays per kit
| Short term stability: 2-8oC,
Long term stability: See individual component labels
|> 2 years under recommended storage conditions
|Limit of Detection:
|Total Assay Time:
|~ 30 min
|Cereal flours, fermentation broths and other materials.
|AACC Method 22-02.01, AOAC Method 2002.01, ICC Standard No. 303, RACI Standard Method and CCFRA (Flour Testing Working Group Method 0018)
The Ceralpha Method: α-Amylase test kit is suitable for the specific measurement and analysis of α-amylase in cereal grains and fermentation broths (fungal and bacterial).
Browse the complete list of our enzyme activity assay kits.
- Very cost effective
- All reagents stable for > 2 years after preparation
- Very specific
- Simple format
- Mega-Calc™ software tool is available from our website for hassle-free raw data processing
- Standard included
A novel enzymatic method discriminating wheat pre-harvest sprouting from Late Maturity alpha-amylase.
Mangan, D., Draga, A., Ivory, R., Cornaggia, C., Blundell, M., Howitt, C., McCleary, B. V. & Ral, J. P. (2022). Journal of Cereal Science, 105, 103480.
The primary quality assessor of wheat grain is the Hagberg Falling Number (FN) method. This is a viscometric test surrogate for α-amylase activity. Despite being used for over sixty years, FN has been increasingly scrutinised due to its low throughput, poor reproducibility and inability to differentiate between the causes of low FN including Pre-harvest Sprouting (PHS) and Late Maturity α-Amylase (LMA). Our study describes initial efforts to analyse a specific wheat flour set tailored for the identification of enzymatic candidates that would allow discrimination between PHS and LMA affected grains. Using the sensitive enzyme-coupled assay substrate R-AMGR3, results suggest that α-glucosidase (exo-α-glucosidase) is a potential enzyme marker candidate to specifically detect sprouted but not LMA-affected grain.Hide Abstract
Diastatic power and maltose value: a method for the measurement of amylolytic enzymes in malt.
Charmier, L. M., McLoughlin, C. & McCleary, B. V. (2021). Journal of the Institute of Brewing, In Press.
A simple method for measurement of the amylolytic activity of malt has been developed and fully evaluated. The method, termed the Maltose Value (MV) is an extension of previously reported work. Here, the MV method has been studied in detail and all aspects of the assay (sample grinding and extraction, starch hydrolysis, maltose hydrolysis and determination as glucose) have been optimised. The method is highly correlated with other dextrinising power methods. The MV method involves extraction of malt in 0.5% sodium chloride at 30°C for 20 minutes followed by filtration; incubation of an aliquot of the undiluted filtrate with starch solution (pH 4.6) at 30°C for 15 min; termination of reaction with sodium hydroxide solution; dilution of sample in an appropriate buffer; hydrolysis of maltose with a specific α-glucosidase; glucose determination and activity calculation. Unlike all subsequent reducing sugar methods, the maltose value method measures a defined reaction product, maltose, with no requirement to use equations to relate analytical values back to Lintner units. The maltose value method is the first viable method in 130 years that could effectively replace the 1886 Lintner method.Hide Abstract
Measurement of available carbohydrates in cereal and cereal products, dairy products, vegetables, fruit and related food products and animal feeds: First Action 2020.07.
McCleary, B. V. & McLoughlin, C. (2021). Journal of AOAC International, qsab019.
Background: The level of available carbohydrates in our diet is directly linked to two major diseases; obesity and Type II diabetes. Despite this, to date there is no method available to allow direct and accurate measurement of available carbohydrates in human and animal foods. Objective: The aim of this research was to develop a method that would allow simple and accurate measurement of available carbohydrates, defined as non-resistant starch, maltodextrins, maltose, isomaltose, sucrose, lactose, glucose, fructose and galactose. Method: Non-resistant (digestible) starch is hydrolysed to glucose and maltose by pancreatic α-amylase and amyloglucosidase at pH 6.0 with shaking or stirring at 37°C for 4 h. Sucrose, lactose, maltose and isomaltose are completely hydrolyzed by specific enzymes to their constituent monosaccharides, which are then measured using pure enzymes in a single reaction cuvette. Results: A method has been developed that allows the accurate measurement of available carbohydrates in all cereal, vegetable, fruit, food, and feed products, including dairy products. Conclusions: A single-laboratory validation was performed on a wide range of food and feed products. The inter-day repeatability (%RSDr) was <3.58% (w/w) across a range of samples containing 44.1 to 88.9% available carbohydrates. The LOD and LOQ obtained were 0.054% (w/w) and 0.179% (w/w), respectively. The method is all inclusive, specific, robust and simple to use. Highlights: A unique method has been developed for the direct measurement of available carbohydrates, entailing separate measurement of glucose, fructose and galactose; information of value in determining the glycemic index of foods.Hide Abstract
Measurement of available carbohydrates, digestible, and resistant starch in food ingredients and products.
McCleary, B. V., McLoughlin, C., Charmier, L. M. J. & McGeough, P. (2019). Cereal Chemistry, 97(1), 114-137.
Background and objectives: The importance of selectively measuring available and unavailable carbohydrates in the human diet has been recognized for over 100 years. The levels of available carbohydrates in diets can be directly linked to major diseases of the Western world, namely Type II diabetes and obesity. Methodology for measurement of total carbohydrates by difference was introduced in the 1880s, and this forms the basis of carbohydrate determination in the United States. In the United Kingdom, a method to directly measure available carbohydrates was introduced in the 1920s to assist diabetic patients with food selection. The aim of the current work was to develop simple, specific, and reliable methods for available carbohydrates and digestible starch (and resistant starch). The major component of available carbohydrates in most foods is digestible starch. Findings: Simple methods for the measurement of rapidly digested starch, slowly digested starch, total digestible starch, resistant starch, and available carbohydrates have been developed, and the digestibility of phosphate cross‐linked starch has been studied in detail. The resistant starch procedure developed is an update of current procedures and incorporates incubation conditions with pancreatic α‐amylase (PAA) and amyloglucosidase (AMG) that parallel those used AOAC Method 2017.16 for total dietary fiber. Available carbohydrates are measured as glucose, fructose, and galactose, following complete and selective hydrolysis of digestible starch, maltodextrins, maltose, sucrose, and lactose to glucose, fructose, and galactose. Sucrose is hydrolyzed with a specific sucrase enzyme that has no action on fructo‐oligosaccharides (FOS). Conclusions: The currently described “available carbohydrates” method together with the total dietary fiber method (AOAC Method 2017.16) allows the measurement of all carbohydrates in food products, including digestible starch. Significance and novelty: This paper describes a simple and specific method for measurement of available carbohydrates in cereal, food, and feed products. This is the first method that provides the correct measurement of digestible starch and sucrose in the presence of FOS. Such methodology is essential for accurate labeling of food products, allowing consumers to make informed decisions in food selection.Hide Abstract
Prediction of potential malt extract and beer filterability using conventional and novel malt assays.
Cornaggia, C., Evans, D. E., Draga, A., Mangan, D. & McCleary, B. V. (2019). Journal of Institute of Brewing, 125(3), 294-309.
Colourimetric assays were used to measure the activities of six key hydrolases endogenous to barley: β‐glucanase, xylanase, cellulase, α-amylase, beta‐amylase and limit dextrinase. The analysed barley malt samples were previously characterised by 27 conventional malt quality descriptors. Correlations between enzymatic activities and brewing parameters such as extract yield, fermentability, viscosity and filterability were investigated. A single extraction protocol for all six hydrolases was optimised and used for multi‐enzyme analysis using fully automatable assay formats. A regression analysis between malt parameters was undertaken to produce a relationship matrix linking enzyme activities and conventional malt quality descriptors. This regression analysis was used to inform a multi‐linear regression approach to create predictive models for extract yield, apparent attenuation limit, viscosity and filterability using the Small‐scale Wort rapId Filtration Test (SWIFT) and two different mashing protocols – Congress and a modified infusion mash at 65oC (MIM 65oC). It was observed that malt enzyme activities displayed significant correlations with the analysed brewing parameters. Both starch hydrolases and cell wall hydrolase activities together with modification parameters (i.e. Kolbach index) were found to be highly correlated with extract yield and apparent attenuation limit. Interestingly, it was observed that xylanase activity in malts was an important predictor for wort viscosity and filterability. It is envisaged that the automatable measurement of enzyme activity could find use in plant breeding progeny selection and for routine assessment of the functional brewing performance of malt batches. This analytical approach would also contribute to brewing process consistency, product quality and reduced processing times.Hide Abstract
Measurement of Starch: Critical evaluation of current methodology.
McCleary, B. V., Charmier, L. M. J. & McKie, V. A. (2018). Starch‐Stärke, 71(1-2), 1800146.
Most commonly used methods for the measurement of starch in food, feeds and ingredients employ the combined action of α‐amylase and amyloglucosidase to hydrolyse the starch to glucose, followed by glucose determination with a glucose oxidase/peroxidase reagent. Recently, a number of questions have been raised concerning possible complications in starch analytical methods. In this paper, each of these concerns, including starch hydrolysis, isomerisation of maltose to maltulose, effective hydrolysis of maltodextrins by amyloglucosidase, enzyme purity and hydrolysis of sucrose and β‐glucans have been studied in detailed. Results obtained for a range of starch containing samples using AOAC Methods 996.11 and 2014 .10 are compared and a new simpler format for starch measurement is introduced. With this method that employs a thermostable α-amylase (as distinct from a heat stable α-amylase) which is both stable and active at 100°C and pH 5.0, 10 samples can be analysed within 2 h, as compared to the 6 h required with AOAC Method 2014.10.Hide Abstract
Measurement of α-Amylase in Cereal, Food and Fermentation Products.
McCleary, B. V. & Sturgeon, R. (2002). Cereal Foods World, 47, 299-310.
In General, the development of methods for measuring α-amylase is pioneered in the clinical chemistry field and then translated to other industries, such as the cereals and fermentation industries. In many instances, this transfer of technology has been difficult or impossible to achieve due to the presence of interfering enzymes or sugars and to differences in the properties of the enzymes being analysed. This article describes many of the commonly used methods for measuring α-amylase in the cereals, food, and fermentation industries and discusses some of the advantages and limitations of each.Hide Abstract
Measurement of α-amylase activity in white wheat flour, milled malt, and microbial enzyme preparations, using the ceralpha assay: Collaborative study.
McCleary, B. V., McNally, M., Monaghan, D. & Mugford, D. C. (2002). Journal of AOAC International, 85(5), 1096-1102.
This study was conducted to evaluate the method performance of a rapid procedure for the measurement of α-amylase activity in flours and microbial enzyme preparations. Samples were milled (if necessary) to pass a 0.5 mm sieve and then extracted with a buffer/salt solution, and the extracts were clarified and diluted. Aliquots of diluted extract (containing α-amylase) were incubated with substrate mixture under defined conditions of pH, temperature, and time. The substrate used was nonreducing end-blocked p-nitrophenyl maltoheptaoside (BPNPG7) in the presence of excess quantities of thermostable α-glucosidase. The blocking group in BPNPG7 prevents hydrolysis of this substrate by exo-acting enzymes such as amyloglucosidase, α-glucosidase, and β-amylase. When the substrate is cleaved by endo-acting α-amylase, the nitrophenyl oligosaccharide is immediately and completely hydrolyzed to p-nitrophenol and free glucose by the excess quantities of α-glucosidase present in the substrate mixture. The reaction is terminated, and the phenolate color developed by the addition of an alkaline solution is measured at 400 nm. Amylase activity is expressed in terms of Ceralpha units; 1 unit is defined as the amount of enzyme required to release 1 µmol p-nitrophenyl (in the presence of excess quantities of α-glucosidase) in 1 min at 40°C. In the present study, 15 laboratories analyzed 16 samples as blind duplicates. The analyzed samples were white wheat flour, white wheat flour to which fungal α-amylase had been added, milled malt, and fungal and bacterial enzyme preparations. Repeatability relative standard deviations ranged from 1.4 to 14.4%, and reproducibility relative standard deviations ranged from 5.0 to 16.7%.Hide Abstract
Analysis of feed enzymes.
McCleary, B. V. (2001). “Enzymes in Farm Animal Nutrition”, (M. Bedford and G. Partridge, Eds.), CAB International, pp. 85-107.
Enzymes are added to animal feed to increase its digestibility, to remove anti-nutritional factors, to improve the availability of components, and for environment reasons (Campbell and Bedford, 1992; Walsh et al., 1993). A wide-variety of carbohydrase, protease, phytase and lipase enzymes find use in animal feeds. In monogastric diets, enzyme activity must be sufficiently high to allow for the relatively short transit time. Also, the enzyme employed must be able to resist unfavourable conditions that may be experienced in feed preparation (e.g. extrusion and pelleting) and that exist in the gastrointestinal tract. Measurement of trace levels of enzymes in animal feed mixtures is difficult. Independent of the enzyme studied, many of the problems experienced are similar; namely, low levels of activity, extraction problems inactivation during feed preparation, non-specific binding to other feed components and inhibition by specific feed-derived inhibitors, e.g. specific xylanase inhibitors in wheat flour (Debyser et al., 1999).Hide Abstract
Sheehan, H. & McCleary, B. V. (1988). Biotechnology Techniques, 2(4), 289-292.
A procedure for the measurement of fungal and bacterial α-amylase in crude culture filtrates and commercial enzyme preparations is described. The procedure employs end-blocked (non-reducing end) p-nitrophenyl maltoheptaoside in the presence of amyloglucosidase and α-glucosidase, and is absolutely specific for α-amylase. The assay procedure is simple, reliable and accurate.Hide Abstract
Measurement of cereal α-Amylase: A new assay procedure.
McCleary, B. V. & Sheehan, H. (1987). Journal of Cereal Science, 6(3), 237-251.
A new procedure for the assay of cereal α-amylase has been developed. The substrate is a defined maltosaccharide with an α-linked nitrophenyl group at the reducing end of the chain, and a chemical blocking group at the non-reducing end. The substrate is completely resistant to attack by β-amylase, glucoamylase and α-glucosidase and thus forms the basis of a highly specific assay for α-amylase. The reaction mixture is composed of the substrate plus excess quantities of α-glucosidase and glucoamylase. Nitrophenyl-maltosaccharides released on action of α-amylase are instantaneously cleaved to glucose plus free p-nitrophenol by the glucoamylase and α-glucosidase, such that the rate of release of p-nitrophenol directly correlates with α-amylase activity. The assay procedure shows an excellent correlation with the Farrand, the Falling Number and the Phadebas α-amylase assay procedures.Hide Abstract
Characterisation of physicochemical parameters and antibacterial properties of New Caledonian honeys.
Bucekova, M., Godocikova, J., Gueyte, R., Chambrey, C. & Majtan, J. (2023). Plos one, 18(10), e0293730.
Honey is an attractive natural product with various health benefits. A few honey-based commercial products have successfully been adopted in clinics to improve wound healing. However, screening of other potential sources of medical-grade honey, in particular, honeys from territories with high floral species diversity and high endemicity, is highly needed. The goal of this study was to characterise the physicochemical and antibacterial properties of New Caledonian honey samples (n = 33) and to elucidate the major mechanism of their antibacterial action. Inhibitory antibacterial activity of honeys against Staphylococcus aureus and Pseudomonas aeruginosa was determined with a minimum inhibitory concentration (MIC) assay. Enzymatic activity of glucose oxidase and the content of hydrogen peroxide (H2O2) in honey samples were analysed. Furthermore, total protein content of honeys together with their electrophoretic protein profiles were also determined in the study. The antibacterial efficacy of 24% of the tested honey samples was slightly superior to that of manuka honey with unique manuka factor 15+. The antibacterial activity of catalase-treated honey sample solutions was significantly reduced, suggesting that H2O2 is a key antibacterial compound of diluted honeys. However, the kinetic profiles of H2O2 production in most potent honeys at a MIC value of 6% was not uniform. Under the experimental conditions, we found that a H2O2 concentration of 150 μM in diluted honeys is a critical concentration for inhibiting the growth of S. aureus. In contrast, 150 μM H2O2 in artificial honey solution was not able to inhibit bacterial growth, suggesting a role of phytochemicals in the antibacterial activity of natural honey. In addition, the continuous generation of H2O2 in diluted honey demonstrated an ability to counteract additional bacteria in re-inoculation experiments. In conclusion, the tested New Caledonian honey samples showed strong antibacterial activity, primarily based on H2O2 action, and therefore represent a suitable source for medical-grade honey.Hide Abstract
Quantifying techno-functional properties of ingredients from multiple crops using machine learning.
Lie-Piang, A., Hageman, J., Vreenegoor, I., van der Kolk, K., de Leeuw, S., van der Padt, A. & Boom, R. (2023). Current Research in Food Science, 7, 100601.
Food ingredients with a low degree of refining consist of multiple components. Therefore, it is essential to formulate food products based on techno-functional properties rather than composition. We assessed the potential of quantifying techno-functional properties of ingredient blends from multiple crops as opposed to single crops. The properties quantified were gelation, viscosity, emulsion stability, and foaming capacity of ingredients from yellow pea and lupine seeds. The relationships were quantified using spline regression, random forest, and neural networks. Suitable models were picked based on model accuracy and physical feasibility of model predictions. A single model to quantify the properties of both crops could be created for each techno-functional property, albeit with a trade-off of higher prediction errors as compared to models based on individual crops. A reflection on the number of observations in each dataset showed that they could be reduced for some properties.Hide Abstract
Comparative analysis of malt quality and starch characteristics of three South Korean barley cultivars.
Park, J., Chung, H. J., Park, H. Y., Park, H. J. & Oh, S. K. (2023). Food Science and Biotechnology, 1-11.
In this study, malt was produced in pilot-scale facilities and conditioned using three barley (Hordeum vulgare L.) cultivars in South Korea (Heugho, Hopum, and Kwangmaeg). Quality and starch characteristics were compared. The starch content was considerably reduced in all malts. Coleoptile elongation was higher in Heugho (HHM; 85.7% ± 12.6%) and Hopum (HPM; 83.9% ± 10.7%) than in Kwangmaeg (KMM; 78.1% ± 9.9%) malt. Malt yield ranged from 81.8 to 84.9%, with no significant difference. All samples presented type A crystallinity, and granules showed discoid shapes. After malting, the mono- and di-saccharide contents (not including sucrose) were increased. The fermentable sugar level was the highest in HHM, whereas non-fermentable sugar was the highest in KMM. These results suggest that HPM enables efficient scarification based on the rapid degradation of starch, while Heugho barley and HHM have a high potential for beer and malt production, respectively.Hide Abstract
Barley yield and malt quality affected by fall and spring planting under rainfed conditions.
Saygili, I. (2023). PeerJ, 11, e15802.
Background: As a result of the changing climate characteristics, it is necessary to reevaluate the planting time for crop plants. The aim of the present study was to determine the quality characteristics of malting barley cultivars in fall and spring plantings. Methods: Sixteen malting barley cultivars were used. Two fall-planted and two spring-planted trials were conducted in two consecutive years. The field trials were carried out in a randomized complete block design with four replications in Tokat province of Turkey under rainfed conditions. Results: Grain yields varied between 4.38 and 5.71 t/ha in fall-planted trials and between 3.12 and 4.89 t/ha in spring-planted trials. Malt extracts were between 77.0% and 78.0% kg in fall-planted trials and between 73.9% and 76.9% in spring-planted trials. Alpha amylase activities ranged from 77.9 to 81.4 Ceralpha unit (CU)/g in fall-planted trials and from 80.8 to 100.9 CU/g in spring-planted trials. Diastatic power ranged from 194.5 to 331.1 Windisch-Kolbach unit (°WK) in fall-planted trials and from 129.0 to 259.8 °WK in spring-planted trials. GGE biplot analysis indicated that winter barley cultivar Durusu and facultative barley cultivar Ince-04 were the best with consistent grain yields while Ince-04 was the best with stable malt extract across the trials. In scatter plot graphics, winter barley cultivars Durusu, Aydanhanim, Yildiz and facultative Ince-04 had superior performance in fall-plantings for grain yield and malt extract. In spring planting, facultative Ince-04 had higher performance than those of other cultivars. In spring plantings, facultative or winter barley cultivars that do not have strong vernalization requirement had better yield and malt quality. Appropriate planting time and cultivars can allow a better use of available water in malt barley production under rainfed conditions. Lastly, instead of evaluating the grain yield or malt quality alone, it would be best to evaluate the target product (malt extract percentage) obtained from a particular region, process, or production methodology.Hide Abstract