Carbohydrate fruit ripening

Obviously inspired by these projects, Moyna et al, [80] investigated the dissolution of banana pulp in [bmim]Cl via 13C NMR spectroscopy. They found substantial variations in the carbohydrate composition for different samples which could potentially be used for the analysis of fruit ripening. 

Changes in molecular weight and carbohydrate composition of cell wall polyuronide and hemicellulose during ripening in strawberry fruit... 

Application of ethylene-,4C to plants resulted in only a 2.4% conversion into soluble carbohydrates, 11% into ether-soluble materials, 6.9% into phytol, 31.7% into cellulose and lignin, and 9.6% into soluble protein and non-protein material, mainly phosphates. 9 Treatment of detached fruit (such as apples, bananas, peaches, figs, and pears) with synthetic auxins, especially (2,4,5-trichlorophenoxy) acetic acid, speeded up ripening, as indicated by color, taste, softness, and starch breakdown. 7 Other fruits have been similarly ripened, 8 and the treatments are effective both on climacteric and non-climacteric fruit. 

This inhibition of the interactions between tannins and salivary protein by carbohydrates has been proposed to contribute to the loss of astringency during ripening of some fruits (Luck et al. 1994 Ozawa et al. 1987 Taira et al. 1997). 

Nogata, Y., Yoza, K., Kusumoto, K. and Ohta, H. 1995. Changes in molecular weight and carbohydrate composition of cell wall polyuronide and hemicellulose during ripening in strawberry fruit, in Pectins and Pectinases, eds., J. Visser and A.G.J. Voragen, Amsterdam Elsevier, pp. 591-596. 

Vierhuis, E., Schols, H.A., Beldman, G. and Voragen, A.G.J. 2000. Isolation and characterisation of cell wall material from olive fruit (Olea europaea cv koroneiki) at different ripening stages, Carbohydr. Polym., 43(1) 11—21. 

Circumstantial evidence suggests that the complexation of polyphenols with proteins is modified by carbohydrates, other phenols and nitrogen-containing metabolites. Correspondingly the influence of polyphenols on the properties of plant materials - for example the changes in astringency of fruits as they ripen or in storage - is substantially modified. 

In the higher plants and particularly the fruits, the polyols appear to function as reserve carbohydrate, the amount present being seasonal and becoming less as the sugars increase during the ripening process. 

Enzymes that cleave polysaccharides are of interest for plant foods. Examples are processes that occur in the ripening of fruit (cf. 18.1.3.3.2), in the processing of flour to cakes and pastries (cf 15.2.2.1), and in the degradation of cereals in preparation for alcoholic fermentation (cf 20.1.4). In addition, enzymes of this t) e are used in food technology (cf 2.7.2.2) and in carbohydrate analysis (cf Table 2.16 and 4.4.6). The following hydrolases are of special importance. 

During ripening of fruits, significant changes occur in the carbohydrate fraction. For example, between picking and onset of decay in apples about 20% of the available carbohydrates have been utilized. 

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