A Study on the suitability of unmalted sorghum as a brewing adjunct

Grain samples of thirteen sorghum cultivars with diverse chemical composition were assessed for their suitability as brewing adjuncts based on proximate analysis. Sieving analysis of the grain as well as hot water extractables (HWE), hot water extractable protein (HWEP) and free amino nitrogen (FAN) were also determined. Cultivars with high starch and amylose contents together with low protein and fat percent are better suited as adjuncts depending on their hot water extracts and hot water extractable protein yields. Large variations in the uniformity of grain size were found, two of these cultivars (CSV-14R and M 35-1) had highest grain size. Cultivars CSH-5, CSV-11 and CSV-13 among the released cultivars were identified as better adjuncts which could be used along with barley malt for brewing lager beer

Role of soluble, cell wall bound phenolics, tannin and flavonoid contents in maize resistance to pink stem borer Sesamia inferens Walker

The pink stem borer Sesamia inferens Walker is an important pest of winter maize which causes significant yieldlosses. In an attempt to identify the biochemical basis of resistance against S. inferens, total soluble phenolics, boundphenolics, cell wall-bound hydroxycinnamic acids-p-coumaric acid (p-CA), ferulic acid (FA), total tannin contentand total flavonoid contents, were measured in leaf at 10, 20 days after germination (DAG); stem at 20, 40 DAG;pith and rind tissues at 60 DAG (stem differentiated). From the present study, it was found that bound phenolics,p-CA, ferulic acid and total tannin contents contribute to the maize defense mechanism against S. inferens. Totalbound phenolic content showed negative correlation with Leaf Injury Rating (LIR). Highly significant strong positivecorrelation (+0.9750) was observed between LIR and total soluble phenolics in leaf tissue at 20 DAG. Similarlyhighly significant strong positive correlation between LIR and total tannins (+0.9354**) and flavonoids (+0.9582**)in pith at 60 DAG was observed. Further, a strong significant positive correlation was also observed between LIRand p-CA (+0.9199*) in pith at 60 DAG and total ferulic acid (+0.9051*) in rind at 60 DAG. The significant strong negativecorrelation between LIR and p-CA (-0.8441*) in stem at 40 DAG was observed. The total bound phenolicsin rind at 60 DAG (0.756), in leaf at 20 DAG (0.681), and total soluble phenolics in the stem at 20 DAG (0.685) showedhigher loadings with PC1, PC2, and PC3, respectively. Genotype-by-biochemical factor biplot showed that thedata of biochemical parameters measured in different tissues and stages could be able to group the genotypesaccording to their reaction to S. inferens

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Not AvailableA simple, sensitive and indirect spectrophotometric method for the determination of protein precipitable polyphenols (tannins) has been developed, based on the ability of the polyphenols to precipitate the synthetic, brown coloured azo-pro- tein, bovine serum albumin±benzidine conjugate (BSA±benzidine, mole ratio 1:7), which shows an absorption maxima at 405 nm. The amount of unprecipita- ted BSA±benzidine is measured directly at 405 nm, which is inversely related to the polyphenol concentration. Tannic acid was used as a reference standard. The microassay was performed in citrate/phosphate bu er (0.1 m), pH 4.8. The method was found to be linear in the range of 5±150 g (3±88 nmol) of tannic acid (y=1.0+(ÿ0.007)x; r=ÿ0.989). Spiking studies carried out with various levels of tannic acid (0.01, 0.1 and 1.0%) indicated a recovery in the range of 94± 101% and 94±98% in rice and sorghum samples, respectively. Free phenolics, when added in the range of 50±150 g (catechin, chlorogenic acid, ferulic acid, ca eic acid and p-coumaric acid) had no in¯uence on the protein precipitation in the microassay. Also spectral analysis of free phenolics and acid-methanolic sor- ghum extracts showed no interference in the present method. The conjugate was found to be stable over a period of 24 weeks in a freeze-dried condition and at 4 C, with <5% deterioration in aqueous condition. The microassay method developed has been used for the quantitation of protein precipitable polyphenols in various sorghum (Sorghum bicolor L. Moench) genotypes and compared with the widely used Folin±Denis chemical method of analysis.Not Availabl

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Not AvailableCultivars of sorghum with different endosperm ch aracteristicwse res tudiedw ith regardt o developmenotf alpha-amylasaeft er differentd urationso f steepinga nd germinationa t 30o C. The optimum alpha-amylaasect ivitiesin all cultivarsw ere observeadf ters teepinfgo r 20h . Thea lpha-amylaascet ivityi ncreaserda pidly,b ut at differenmt agnitudesin, mostc ultivarsd uringg erminationr,e achinga peaka ctivity at 96h . After 120h , howevera, ctivityw asr educeds ignificantlyS. teepingfo r 20h followedb y germinationfo r 96h wasf oundt o bet he optimalm altingc onditionf or comparativeev aluationo fdiverses orghumc ultivarsA. three-t o four-foldv ariation in alpha-amylaasen dd iastatica ctivitiesw aso bserveadm ong2 9w hites eedeIdn dian cultivarsA. lpha-amylasaec tivitya ndd iastatica ctivityw eref oundt o bes ignificantly correlate(dr :0.88) in these cultivars.Not Availabl