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Blanching, a pre-processing procedure, is usually carried out to inhibit enzymatic and other reactions which contribute to loss of quality prior to processing of green leafy vegetables. In this work the effect of hot water, steam and microwave blanching on peroxidase inactivation, colour changes, ascorbate degradation and changes in phenolic content of C. esculenta leaves was studied. Hot water and steam blanching were carried out in boiling water and steam, respectively, for 10, 20, 30, 60 and 120 s while microwave blanching was carried out for 5, 10, 15, 20 and 30 s. Peroxidase inactivation was faster in microwave blanched leaves. A 90% inactivation of peroxidase was achieved within 15 s of microwave blanching compared to 120 s and 30 s of hot water and steam blanching, respectively. The highest change in colour (ΔE) and chroma was observed after 20 s of microwave and steam blanching, respectively, although the changes were not significant. All the different blanching techniques resulted in ascorbate degradation, although higher losses were observed with hot water blanching compared to steam and microwave blanching.

Rice is the fastest growing food source in Ghana. The country, however, imports about 70 per cent of its rice requirement due to low volumes of production and poor grain quality of domestic rice compared to imported ones. In the study, 10 popular imported rice brands on the Ghanaian market were characterised for grain quality traits including grain dimensions, apparent amylose content, gelatinisation temperature, paste viscosity properties, and aroma using physiochemical properties and DNA markers. The rice brands came from Asia and the USA. The rice type from Asia was found to be Jasmine-styled aromatic long grained with low amylose content and gelatinisation temperature, whereas those of USA were conventional long grain with intermediate amylose content and gelatinisation temperature. These findings were confirmed through DNA marker analyses, with the rice types from Asia and the USA revealing the presence of the TAC and GCC of the waxy gene SNP haplotypes, respectively. The implication for rice breeding in Ghana is discussed.Original scientific paper. Received 29 Oct. 14; revised 03 Aug 15.

Scab resistance is one of the most important goals of apple breeding, typically achieved by time-consuming and expensive conventional breeding techniques. Cisgenesis, which is the genetic modification of a recipient organism with genes from a crossable—sexually compatible—organism, is a promising tool for plant breeding to develop disease resistance in a rapid way. A cisgenic, scab-resistant line of the apple variety ‘Gala’ expressing the native apple scab resistance gene Rvi6 (formerly HcrVf2) under control of its own regulatory sequences has been recently developed. In this paper, we present the results from a phenotypic, molecular and biochemical evaluation of clonal replicates of this line (C11.1.53). The phenotype (shoot length, shoot diameter, internode length, number of leaves, leaf length and leaf width) of C11.1.53 was compared to that of the Gala parental background over a period of 108 days. Only a few statistically significant differences were detected, which are probably due to small differences in the quality of the budwood used for grafting rather than effects related to the presence of the cisgene. As the expression of a resistance gene can affect the downstream cascade of plant defence responses, a selection of apple defence-related genes was analyzed by quantitative real-time PCR analysis. These genes are also known as major allergen genes in apple. Even if three out of ten apple allergen genes tested in the leaves differed in the cisgenic line compared to both Gala (background) and ‘Florina’ (the variety from which the Rvi6 gene was cloned), using 2D-PAGE, we were unable to find any significant difference in the expressed proteomes of the leaves of C11.1.53 compared to Gala. Results are discussed in the context of a possible use of cisgenic lines for fruit crop improvement.