Quality attributes of different types of cactus pitaya fruits (Stenocereus griseus).

摘要

Pitaya (S. griseus) is a cactus fruit that has been used as a complementary part of diet since ancient times in Southern Mexico. In this region, approximately 30 types of pitayas have been identified but none of them has been characterized for quality attributes. In the present study, six types ('Amarilla', 'Jarra', 'Melon', 'Crema', 'Roja Lisa' and 'Olla') of pitayas were studied to select those with more potential for the fresh or processed market. Samples of mature pitaya fruits were collected for two years (May-June 2002 and June-July 2003) and evaluated for physical, chemical and sensory characteristics. 'Olla' and 'Jarra' types showed the best quality attributes (fruit weight, flesh percentage, total soluble solids and sugar level). Some aroma compounds with herbaceous (aldehydes) and fruity (esters) notes were identified in the six pitaya types, with 'Jarra' showing greater number and amount of volatiles than 'Olla' fruits. The pigments present in the flesh were identified as betalains (betacyanins and betaxanthins) and they differed both qualitatively and quantitatively among the six types, providing characteristic colours to the flesh. Regarding sensory characteristics, only 'Olla' and 'Jarra' fruits were subjected to evaluation by trained panelists and consumers. The trained panelists described the aroma of these two pitaya types as fruity and herbaceous, and detected a bright colour in peel and pulp. Colour and odour variables explained over 80% of variance in the consumers survey. No significant differences in acceptability were found between the two types of pitaya fruits and 73% of the people said they would buy these fruits in the market. 'Olla' and 'Jarra' pitayas will be accepted by middle class Mexican consumers based mostly on pulp colour and fresh aroma..