Barley starch isolation

McDonald, M.L. and Stark, J.R. 1988. A critical examination of procedures for the isolation of barley starch. J. Inst. Brew. 94 125-132. 

Vasanthan, T., Bhatty, R.S., Tyler, R.T., and Chang, P. 1997. Isolation and cationization of barley starches at laboratory and pilot scale. Cereal Chem. 74 25-28. 

The loaf volumes of breads baked from wheat starch coming from different classes of wheat, be it hard red winter, hard red spring, soft red winter or soft white, were similar.436 By contrast, club wheat starch produced a larger loaf volume and durum wheat starch a smaller loaf volume. Other investigators found a range in the loaf volumes of breads baked from wheat starches isolated from different classes of wheat.437 Fractionation and reconstitution studies revealed that rye and barley starches can substitute for wheat starch in producing bread of satisfactory volume. Starches from... 

Table 16.3 Gelatinization parameters of isolated small and large granu normal, waxy and high-amylose barley starches les of...

The wide range in T0, Tp, Tc and AH among genotypes (Table 16.2) could be attributed to differences in cultivars,39,49,52 growth conditions,49,58 and thermal and mechanical conditions employed during starch isolation.66 DSC parameters of barley starches are generally lower than those reported for normal, waxy and high-amylose maize starches examined under identical conditions.28... 

Studies of the rate of the hydrolysis of dextrins isolated from a reaction mixture after the extensive hydrolysis of starch by maltase-free malted barley alpha amylase, led Myrback11 to conclude that the flattening of the reaction curves with this amylase is not due to equilibrium between the amylase and the products of the hydrolysis. As indicated above, similar conclusions have been reached for pancreatic amylase and for the amylase of Aspergillus oryzae.41,7a... 

The French physiologist Anselme Payen (1795-1871) isolates diastase from barley. Diastase catalyzes the conversion of starch into sugar, and is an example of the organic catalysts within living tissue that eventually come to be called enzymes. 

In green algae and in leaf cells of higher plants, ADP-Glc PPase has been demonstrated to reside in the chloroplast (82). More recently, using plastids isolated from maize and barley endosperm (83-85), the existence of two ADP-Glc PPases, a plastidial form, and a major cytosolic form were found. Subsequently, cytosolic forms of ADP-glucose pyrophosphorylase have been found in wheat (86, 87) and rice (88). Because starch synthesis occurs in plastids, it was proposed that in cereal endosperms, synthesis of ADP-Glc in the cytosol requires the involvement of an ADP-Glc carrier in the amyloplast envelope (85). Subsequently, characterization of the ADP-Glc transporter has been reported for maize endosperm (89, 90), barley endosperm (91), and wheat endosperm (92). 

A range of methods have been described in the literature, and we shall consider them in the following order (1) the methods developed at the Food Research Institute-Norwich (FRIN), to isolate cell walls from a range of vegetables and fruits (runner beans, potatoes, cabbage and apples), cereals (oats, wheat and rye) and cereal products (wheat bran and rye biscuits), and lignified tissues (parchment layers of runner bean pods) (2) the special techniques, which may include wet sieving steps, used for the isolation of cell walls from potatoes, wheat endosperm, and wheat and barley aleurone layers (3) alternative methods for the isolation of cell walls from starch and protein-rich products (rice) and (4) methods used for the isolation of cell walls from suspension-cultured tissues. 

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