Canning and evaluation procedures should be standardised to ensure that beans selected, based on canning quality, meet the requirements set by the market and processors. For the purpose of evaluating the canning qualities of small white beans in tomato sauce, three small-scale canning techniques were evaluated, one of which was found to deliver a product with quality parameters similar to those of international standards. Using South African small white bean cultivars and the selected method, Teebus, the cultivar used by industry as the standard to indicate acceptable canning quality, displayed better visual appearance and less split beans than with the other two methods. The percentage washed drained weight and texture values of Teebus were also in agreement with international standards. The evaluation procedure for the small white beans after canning was also optimised, by comparing two procedures, which identified texture, visual appearance (scale 1 to 10), splits (scale 1 to 10), hydration coefficient, clumping, size and colour as the statistically most suitable quality parameters. With the aid of the developed method, it was possible to define standard values for South African 'choice' and 'standard' grade beans, which previously was based only on 'visual inspection' by a trained inspection panel.

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The use of laboratory canning techniques to predict the commercial canning quality of dry beans is widely accepted in bean breeding. The validation of laboratory canning procedures is determined by its relationship with commercial practices. Laboratory evaluation of the canning quality of industrially canned beans obtained from retailers stressed that canning quality standards for South African small white beans in tomato sauce need defining. Four small white bean cultivars were canned and evaluated according to laboratory procedures and the same cultivars were supplied to an industrial canner to be canned according to industrial procedures. Different canning parameters used in the laboratory (hydration coefficient, percentage washed drained weight, visual appearance, splits, size, texture and colour) and by industry (water uptake, percentage washed drained weight, splits, size) necessitated the use of multivariate analysis to compare the two sets of data. Canonical variate analyses showed the same groupings of cultivars according to canning quality for laboratory and industrial canning. Laboratory procedures were therefore as successful as industrial procedures in grouping cultivars according to canning quality. For bean breeding purposes, it was also shown that the laboratory canning and evaluation method is able to detect the same environmental and genetic effects on canning quality that also affect industrial canning.

When sorghum hybrids replaced varieties in South Africa, the average malt quality quantified as sorghum diastatic units (SOU) declined. Additionally, malt quality of sorghum needs to be increased if sorghum is to be used as extenders or substitutes for barley malt in the lager beer industry. Trials were carried out in order to study the effect of Xenia and heterosis in F 1 and F2 seeds produced in various hybrid combinations. Large Xenia effects were observed in the F1 but this was entirely lost in the F2 generation. Effectively, most hybrids showed negative heterosis. One R-line seemed to pass on stability in SOU to its offspring. Ways of improving malt quality are discussed.Toe sorghum varieteite met basters in Suid-Afrika vervang is, het die gemiddelde moutkwaliteit, wat as sorghum diastase eenhede (SOU) gekwantifiseer word, gedaal. Ook moet moutkwaliteit van sorghum verhoog word om dit as verlenger of vervanger van garsmout in die lagerbierbedryf te kan benut. Eksperimente is uitgevoer om die effek van Xenia en heterose in die F1 en F2 van verskillende basterkombinasies te bestudeer. Omvangryke Xenia-effekte is in die F1 waargeneem, maar dit het in die F2 generasie heeltemal vE;!rdwyn. Die meeste basters het negatiewe heterose getoon. Een R-Iyn het skynbaar stabiliteit in SOU aan sy nageslag oorgedra. Maniere om moutkwaliteit te verbeter, word bespreek.