OPUNTIA PROCESSING AND USES: FOODS AND NATURAL INGREDIENTS FROM CACTUS PEAR AND CLADODES - Carmen Sáenz

Depto. de Agroindustria y Enología, Facultad de Ciencias Agronómicas, Universidad de Chile, Santiago, Chile

The Opuntia genus are plants with many industrial uses, mainly for the food industry, but also with a potential for the natural ingredients industry. The fruits and the cladodes reveal a group of components with functional properties, the study of which has only recently commenced. The fiber, vitamins, mucilage and some antioxidants (betalains, ascorbic acid, etc) are some of the compounds that can be extracted and added to other foods, thereby constituting an advantage to the foods prepared with cactus pear or cladodes. Another attractive characteristic of this plant is the possibility of having different fruit colors (green or white, yellow, orange, red and purple). Some technological characteristics of the fruit, i.e. low acidity, high pH and high soluble solids content are a challenge for its processing, since the fruit seems to be a good medium for the growth of microorganisms. The instability of pigments, mainly the green ones (chlorophylls), during thermal treatments are another problem to solve. Fruit is mainly consumed fresh, but their processing, as in other fruits, add value. In this crop the more possibilities of processing there are, the better. Some of the latest studies refer to minimally processed fruit, presenting the consumer with peeled fruit and the option of domestic preparation. Some techniques applied towards the processing of cactus pear and cladodes, are commonly used to preserve other fruits and vegetables, i.e. until now dehydration is only used experimentally to prepare fruit leathers, with a low aw, as products which provide energy.  Some experience exists in terms of canned fruits and concentrated juices or nectars consisting of pure cactus pear, or with cactus pear blended with other fruit juices as an alternative. Preparation of syrups from cactus pear juice, to be used as liquid sugar has also been studied. This, together with different kinds of marmalades, etc., are some of the products that can be obtained, or are actually commercialized, from Opuntia in some countries. The cladodes, mainly young cladodes (10-12 cm), known as “nopalitos” in México and the south of the U.S.A., and prepared in a pickled or salted form have a high acceptance as vegetable and are added to many dishes. Nopalitos are also offered as a candied snack. At present there are some efforts underway to introduce this manner of consumption of cladodes in some south American countries. Some of the natural ingredients obtained from the fruits and the cladodes are pigments, as betalains, hydrocolloid (mucilage) from the cladodes, as well as fibre (nopal flour) that can be blended with wheat flour for the preparation of biscuits. For most of the technologies and different products mentioned above there are flow-sheets and specifications that will be presented and discussed.