Today, one speaks of fourth range or minimally processed products to refer to fresh fruit and vegetables that have been washed, cut up and packaged before they are marketed.
As this researcher explained, "a few years ago it was discovered that sulphites could cause health problems in certain sectors of the population, so their use was banned in foods that could be consumed directly, like fruit and vegetables. In the case of potatoes, which are not eaten raw, sulphites continue to be used, so my thesis has focussed on finding alternative substances".
The thesis is entitled "Estudio de estrategias para la conservación de patatas (cv.Monalisa) mínimamente procesadas" (Study of strategies to preserve minimally processed potatoes [cv. Monalisa]). The study assessed various preserving techniques as alternatives to the use of sulphites to maintain the quality of minimally processed potatoes stored for a fortnight at 4 degrees Celsius. To prevent the product turning brown, natural solutions and/or their by-products were used. When monitoring the browning, the results indicated that "both the solution combining 4-Hexylresorcinol with ascorbic acid and the extracts of green tea and garlic studied can be used as anti-browning agents for preservation purposes in a refrigerated state over a 14-day period". As regards the texture modifiers studied, used in combination with the selected anti-browning solution, "a short, low-temperature thermal shock was used which maintained product quality over at least 14 days".