Determination of the contents of A- and B-starches in barley using Low Angle Laser Light Scattering

Abstract

BOHAČENKO I., CHMELÍK J., PSOTA V. (2006): Determination of the contents of A-and B-starches in barley using Low Angle Laser Light Scattering. Czech J. Food Sci., 24: 11-18.A method was proposed for the determination of the contents of A-and B-starches in barley and for the use in plant breeding stations and brewing/malting laboratories. A combination was used of classical methods (incl. crushing of barley kernels by a roll crusher, steeping in 0.02M HCl, repeated rubbing and filtering through the sieve of 0.08 mm), and novel pieces of know-how (treatment with β-glucanase and cellulase, alkalisation at pH = 10.0 and centrifugation of crude starch suspension through the layer of CsCl). In this way, barley starch of high purity was obtained at a very low loss, using Low Angle Laser Light Scattering for the determination of the size distribution of starch granules. The boundary of the particle size between the peaks of A-starch and B-starch (7 µm) was evaluated from the distribution curves, while the contents of A-and B-starches were calculated from the cumulative curves. As a whole, the method was internally validated and for its repeatability and uncertainty of measurement the stimates of standard deviation s = 1.56 and confidence interval L 1,2 = x ± 1.9% were established, respectively. Taking into account the generally well known difficulties associated with the extraction of substances from biological materials, in this case the separation of starch from barley kernels, we believe that the proposed method will bring satisfactory results in practice.

Beer-brewing powered by controlled hydrodynamic cavitation: Theory and real-scale experiments

“…The sugar concentration in the wort during mashing and before fermentation was measured in Brix percentage degrees by means of a refractometer (Hanna Instruments, Padova, Italy, model HI 96811, scaled from 0% to 50% Brix, resolution 0.1%, precision ±0.2% in the 0-80°C temperature range, and automatic temperature compensation in the 0-40°C range). Brix readings were then converted to starch extraction efficiency (Bohačenko et al, 2006).…”

“…0% to 50% Brix, resolution 0.1%, precision ±0.2% in the 0-80°C temperature range, and automatic temperature compensation in the 0-40°C range). Brix readings were then converted to starch extraction efficiency (Bohačenko et al, 2006).…”

Development of Barley (Hordeum vulgareL.) Lines with Altered Starch Granule Size Distribution

“…These aggregations make extract turbid, clog filters, and increase wort production cost . Thus, development of malting barley lines with reduced small starch granules should make the malting process more efficient …”

“…24 Thus, development of malting barley lines with reduced small starch granules should make the malting process more efficient. 25 In this report, we describe identification of a Japanese genotype, Kinai Kyoshinkai-2 (KK-2), with a lower ratio between small and large starch granules numbers. To study the extent genetics determined the KK-2 starch granule phenotype, a cross was made between KK-2 and a normal starch granule genotype CDC Kendall and led to the development of lines with large variations in starch granule size distributions.…”

Gluten-Free Beer via Hydrodynamic Cavitation Assisted Brewing of Barley Malts

“…Brix readings were then converted to starch extraction efficiency (Bohačenko, Chmelík, & Psota, 2006).…”