Shedding Light on the Volatile Composition of Broa, a Traditional Portuguese Maize Bread

Abstract

In Portugal, maize has been used for centuries to produce an ethnic bread called broa, employing traditional maize varieties, which are preferred by the consumers in detriment of commercial hybrids. In order to evaluate the maize volatiles that can influence consumers’ acceptance of broas, twelve broas were prepared from twelve maize varieties (eleven traditional and one commercial hybrid), following a traditional recipe. All maize flours and broas were analyzed by HS-SPME-GC-MS (headspace solid-phase microextraction) and broas were appraised by a consumer sensory panel. In addition, the major soluble phenolics and total carotenoids contents were quantitated in order to evaluate their influence as precursors or inhibitors of volatile compounds. Results showed that the major volatiles detected in maize flours and broas were aldehydes and alcohols, derived from lipid oxidation, and some ketones derived from carotenoids’ oxidation. Both lipid and carotenoids’ oxidation reactions appeared to be inhibited by soluble phenolics. In contrast, phenolic compounds appeared to increase browning reactions during bread making and, consequently, the production of pyranones. Traditional samples, especially those with higher contents in pyranones and lower contents in aldehydes, were preferred by the consumer sensory panel. These findings suggest that, without awareness, consumers prefer broas prepared from traditional maize flours with higher contents in health-promoting phenolic compounds, reinforcing the importance of preserving these valuable genetic resources.

New Insights into Identification, Distribution, and Health Benefits of Polyamines and Their Derivatives

“…CPAs have been reported to be widely present in the Poaceae and Solanaceae families, such as barley, wheat, rice, maize, potato, tomato, Lycium berry, bee pollen, and their related food products (Table ). − So far, about 80 different types of CPAs have been identified in edible plants (Table ), including 12 conjugated putrescine, 2 conjugated cadaverine, 39 conjugated spermidine, 20 conjugated spermine, and 8 conjugated agmatine. Notably, bee pollen is evidenced to possess abundant CPAs; ,,, for example, the 31 CPAs and their 33 cis–trans isomers were observed in 20 types of monofloral bee pollen, constituting nearly half of the total identified CPAs in foods .…”