Bean cotyledons

Table 5.6 shows the total phenolic content (determined using the Folin-Ciocalteu assay) and antioxidant activity (ABTS radical scavenging capacity) of extracts from morama bean seed coat and cotyledon prepared with acidified mefhanol. If is clear fhaf morama bean seed coat and cotyledon have appreciable levels of fofal phenolics and antioxidant activity. These phenolics are concentrated in the seed coat. It has been reported that the morama bean cotyledon contains high levels of the amino acid tyrosine (Maruatona et ah, 2010) which is phenolic in nature and can therefore confribufe fo fhe fofal phenolic content of the cotyledon as determined with the Folin-Ciocalteu assay. 

Van Zyl, J. (2007). Marama bean cotyledon and seed coats Phenolic composition and antioxidant activity. Univerity of Pretoria, Pretoria, South Africa B.Sc. Honours Project Report. 

Beckles et al. (2001) showed the presence of a soluble cytosolic ADPG glucophosphorylase in barley. They then measured the ratio of the levels of ADPG to that of UDPG in the endosperm of many cereal endosperms including that of E. coracana, tomato seeds, bean cotyledon, and roots of yam and taro. The ratio varied from 0.30 to 0.64 (0.38 in the endosperm of Eleusine) and varied from 0.01 to 0.04 in the others. The higher ratio in the cereal endosperm was taken as an index of greater activity of the enzyme in these tissues. 

To press cocoa beans in a Duyvis press, the cocoa bean cotyledons are first pulverized into a fluid-like slurry. The slurry is then heated in an agitated conditioning... 

Van Laar, H. S. Tamminga B.A. Williams M.W.A. Verstegen H.A. Schols. Fermentation characteristics of polysaccharide fractions extracted from the cell walls of soya bean cotyledons. /. Sci. PoodAgric. 2000, 80, 1477-1485. 

Reaction 1 is a transamination reaction to form mercaptopyruvate. A transaminase in higher plants which will utilize cysteine or cystine as the amino donor has never been reported. In fact Forest and Wightman (1972) showed that cystine was not an amino donor to any keto acid tested with extracts of bush bean cotyledons or seedlings. It was unique in this respect in that the only other protein amino acids which acted in this manner were the two imino acids proline and hydroxyproline. 

Bean cotyledons Spinach leaves Spinach leaves Spinach leaves Bean embryos Pea embryos Pumpkin endosperm... 

Of the organic acids (1.2-1.6%), citric, acetic, succinic and malic acid contribute to the taste of cocoa (Table 21.23). They are formed during fermentation. The amount of acetic acid released by the pulp and partly retained by the bean cotyledons depends on the duration of fermentation and on the drying method used. Eight brands of cocoa were found to contain 1.22-1.64% total acids, 0.79-1.25% volatile acids and 0.19-0.71% acetic acid. 

Stymne, S. and Appelqvist L-A. (1980). The biosynthesis of linoleate and alpha-linolenate in homogenates from developing soya bean cotyledons. Plant Sci. Lett. 17,287-294. 

F. Barber and J. E. Thompson, Senescence-dependent Increase in the permeability of liposomes prepared from bean cotyledon membranes. 

K.D. Johnson, M.J. Chrispeels, Substrate specificities of N-acetylglucosaminyl-, fucosyl-, and xylosyltransferases that modify glycoproteins in the Golgi apparatus of bean cotyledons. Plant Physiol, 1987, 84, 1301-1308. 

The fat (cocoa butter) of the cocoa beans is important for chocolate production, as it wDl give chocolate its characteristic texture and mouthfeel, depending on the hardness and melting and solidification (crystallization) behavior of the fat (Asep et al. 2008 Beckett 2009 Afoakwa 2010). Fat makes up slightly more than 50% of the mass of dry unfermented cocoa bean cotyledons Forastero beans possess a higher fat content than Criollo beans. The cocoa butter present in the cocoa beans is... 

Physico-chemical processes within the cocoa beans encompass diffusion, internal destruction (due to acetic acid ingress), and enzymatic processes (Figure 16.5), which are influenced by several environmental factors, such as timing of initial entry of molecules and heat, pH (determined by duration, speed and intensity of acidification), temperature (speed of fermentation), and moisture (speed of fermentation and drying) (Schwan et al. 1995 Thompson et al. 2007,2013). Biochemical and physical changes within the bean cotyledons can be divided into two broad phases. The first... 

K. marxianus, as pectinase producer, and the naturally vigorous yeast, 5. cerevisiae, as ethanol producer, might he a better yeast choice for future defined inocula. Moreover, inoculation of fresh cocoa pulp-hean mass with a K. marxianus hybrid yeast strain with increased pectinolytic activity has shown that it affects the microbial community structure during fermentation, increases by one third the volume of sweatings (and hence naturally increasing aeration), stimulates faster and improved cocoa bean protein degradation, results in reduced cocoa bean cotyledon acidity, and hence positively influences the fermented cocoa bean quality as well as the sensory quality of the chocolates produced thereof (Leal et al. 2008). The enhanced pectinolytic activity of K. marxianus has been confirmed during cocoa bean tray fermentation processes inoculated with a culture of this yeast species (Crafack et al. 2013). 

Biehl, B., Passern, D., and Sagemann, W. (1982a) Effect of acetic add on subcellular structures of cocoa bean cotyledons. J Sci Food AgricJA, 1101-1109. 

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