Gebruiksaanwijzing FPP (Figuur Plot Programma) : herziene programma versie (6.1)

Doel van dit onderzoek was: Grafieken tekenen, met behulp van HP plotter, van lijnen waarvan de functie niet bekend is. Er wordt een gebruiksaanwijzing gegeven van een Basic-Plus-2 programma, voor een digital PDP 11 computer om grafieken te plotten zonder regressielijnen te berekenen. De middelbare fout (m.f.) wordt als een vertikaal lijnstuk weergegeven. Om grafieken te kunnen plotten zonder regressie toe te passen is FPP (Figuur Plot Programma) gemaakt. Het programma construeert uit de meetgegevens inclusief middelbare fout een grafiek waarbij de meetpunten verbonden zijn door een rechte lijn en met de middelbare fout als vertikaal lijnstuk. Het programma construeert een figuur welke in principe bedoeld is op om papier van A3 formaat te plotten. De gegevens kunnen via het toetsenbord worden ingevoerd of uit een DATA bestand gelezen worden in de volgorde als gegeven in hoofdstuk 4. Wanneer symbolen over elkaar zouden vallen wordt een symboolverschuiving berekend. De berekende verschuivingen worden met de originele gegevens in een nieuw bestand geplaatst zodat indien gewenst een andere verschuiving toegepast kan worden. Dit nieuwe bestand kan na eventuele correcties ook door het programma gelezen worden. Er worden dan geen nieuwe posities berekend, maar uit dit bestand overgenomen

Application of food irradiation processes to developing countries

The losses in potato tubers during storage are mainly due to sprouting and rotting. Gamma irradiation effectively inhibits sprouting and extends the storage life of potatoes. Rotting can not be controlled within the sprout inhibition close range, but irradiation increases, however, the rot by disturbing the resistance mechanism. For this reason storage experiments were carried out with combination treatments of heat, calcium salicylate, salicylic acid and irradiation. Before treatment the potatoes were artificially damaged and infected with Fusarium sulfurium. After the combined treatments the potatoes were stored at 10 degrees C, 85% RH in order to study the mould growth. It appeared from the results that irradiation with 1 kGy has some effect on the delay of rot. The best results were obtained with a combined treatment of heat with 50 degrees C and irradiation of 1 kGy. A treatment with different concentrations of salicylic acid or calcium salicylate alone or in combination with irradiation has hardly an effect on the prevention of rot caused by Fusarium sulfurium. The results obtained with the combination of chemicals and irradiation are not in agreement with previous research

Application of food irradiation processes to developing countries

Sprouting of- and fungal attack on tuber, bulb and foot products is a common problem to most countries. Sprouting can be delayed by storage at low temperature, and partly prevented by a proper use of chemical sprout inhibitors. Cooling is, however, energy consuming, expensive and not practicabie everywhere. Chemicals are cheaper, but their application is not always reliable, especially at temperatures higher than 15'C. Moreover in some countries the application of chemical inhibitors is prohibited. From research it has been proven that sprout inhibition can also be achieved by an irradiation treatment. However, this treatment can induce rot during storage, especially in (semi)tropical countries. The appearance of rot in potatoes depends of different factors like irradiation dose, postharvest irradiation time, wound healing, dormancy period, storage temperature etc. To solve this rot problem these factors have to be studied. In relation to this probem the following research was set up with the aim: study the effect of a postharvest and postponed irradiation treatment with different doses on sprouting, rot incidence, wound healing, chemical and sensory properties of potatoes. In the framework of this project two experiments were started in September 1985 with the potato cultivar "Bintje". One experiment was focussed on the sprout inhibition and the other on the control of rot. These experiments have been finished at July 1986