Relationship between quality characteristics of cactus pear nopalitos for use as an alternative vegetable source in South Africa

More than 820 million people in the world are suffering from hunger and 1.3 billion from food insecurity. In Africa, food insecurity is rising because of population increase, global warming, and desertification. There is a need for drought-resilient crops that are less impacted by climate change as only climate-smart food systems can lead to food security. Nopalitos are a source of sustainable, economic, and nutritious food and could be an essential feed source to livestock and humans alike. However, farmers and consumers need to know when nopalitos are at their best eating quality. Good quality nopalitos are bright green, thin, soft, fresh-looking, and not too sour or slimy. This paper aims to determine the relationship between the different quality attributes of nopalitos to identify the good quality nopalitos. Data were obtained and correlated from cactus pear nopalitos of two cultivars (Fusicualis and Morado), between 9 cm and 24 cm in length, harvested in two seasons (autumn and spring) and over two years. Morphology (length, weight, width, diameter, surface area, and volume), texture (firmness and compressibility), colour (L*, a*, b*, C* and h°), turgidity, and sliminess (moisture content, mucilage yield, and viscosity) and gustatory (percentage titratable acidity, pH and total soluble solids) were correlated. Nopalito size, texture, colour, acidity, and mucilage yield, and viscosity were interconnected. A high correlation was found between nopalitos that were smaller in length, thinner in diameter, volume, and surface area as they had a softer texture, brighter greener colour, less sliminess, and lower acids. In contrast, nopalitos with longer, thicker, higher volume and surface area had more rigid texture, yellower green colour, sliminess, and higher acids. Young nopalitos have best eating quality because they demonstrate the most quality characteristic.