Fruit quality: new insights for biotechnology

At ripening fruits undergo many changes which include the development of color and aroma and improvements in flavor and texture that make them attractive to potential consumers. Fruits provide an important source of health-related substances, plus minerals and vitamins, and the quality of a fruit is influenced by variety, nutritional status, and environmental conditions during plant growth and fruit development. Ripening is considered to be the main process in fruit development, and all studies had been focused on this process which included physicochemical, biochemical, and molecular analysis. With the development of genomic analysis the strategies to study fruit ripening have been changing and now there are new perspectives and opportunities. The objective of this review is to describe the state of the art in the studies related to fruit ripening with emphasis in molecular studies.     

Chemical composition and in vitro starch bioavailability of Phaseolus vulgaris (L) cv Mayocoba

Common beans of the Mayocoba variety were cooked (178 min) and evaluated regarding their chemical composition and starch digestibility in vitro. Mean physical characteristics of the Mayocoba grain were: thousand‐kernel weight, 443.0 (±0.98)g; length, 12.45 mm; width 7.84 mm and thickness, 6.44 mm. Total starch content in Mayocoba bean was 40.24% (dmb). The available starch was 22.87%, whereas resistant starch accounted for 6.4% and retrograded resistant starch represented 3.3% of the cooked seed weight. None of these values changed with storage time. The Mayocoba variety presented values of soluble indigestible fraction of approximately 8.0% and insoluble indigestible fraction of 36%, which did not change with storage. Both simple enzymatic hydrolysis rate and hydrolysis index (HI = 36%) indicated a slow hydrolysis of Mayocoba starch. HI‐based predicted glycemic index was 39%, all of which suggested a ‘slow carbohydrate’ feature for this bean. Copyright © 2004 Society of Chemical Industry