RESUMO
This research assessed the popcorn quality parameters and nutritional properties of 5 oily maize (Zea mays var. 'Everta') hybrids under several thermal treatments (hot air, microwave, and wet cooking). Grains contained 2.16-4.51 % crude fat and 11.08-12.94 % protein, displayed a similar amount of individual p-coumaric and ferulic acid derivatives (p > 0.05) (free: 3.61-40.53 µg/g; bound: 1621.75-1970.94 µg/g), and total phytosterols ranging from 8.76 to 13.17 µg/g. Hot air- and wet cooking-treated grains showed the highest expansion volume (121.5-133.1 mL), and there were no differences in yield and residual percentage (p < 0.05). PCA analysis clustered samples 1 and 3 as the most influential on bound phenolics, expansion time, yield, and popped grains weight, mostly under hot air and wet cooking treatments. Spearman's correlations outlined the potential of the grains' total and bound phenolics on popping quality (weight and expansion time: 0.50-0.90). Results suggested the oily hybrids' nutritional potential and suitability to produce high-quality popcorn.
RESUMO
Cancer is one of the main chronic degenerative diseases worldwide. In recent years, consumption of whole-grain cereals and their derivative food products has been associated with a reduced risk of various types of cancer. The main biomolecules in cereals include proteins, peptides, and amino acids, all of which are present in different quantities within the grain. Some of these peptides possess nutraceutical properties and exert biological effects that promote health and prevent cancer. In this review, we report the current status and advances in knowledge regarding the bioactive properties of maize peptides, such as antioxidant, antihypertensive, hepatoprotective, and anti-tumor activities. We also highlight the potential biological mechanisms through which maize bioactive peptides exert anti-cancer activity. Finally, we analyze and emphasize the potential applications of maize peptides.
RESUMO
Eleven experimental and three commercial white quality protein maize (QPM) hybrids and two regular endosperm controls were planted at Celaya, Guanajuato, Mexico with the aim of comparing grain physical characteristics, protein quality, lime-cooking and tortilla making properties. All genotypes were planted under irrigation using a density of 80,000 plants/ha and fertilized with 250 kg N-60 P-60 K per hectare. When compared with the controls these QPM genotypes had lower test (77.4 vs. 76.5 kg/hL) and 1,000 kernel weights (327 vs. 307 g), softer endosperm texture (2.5 vs. 1.8 where 1 = soft, 2 intermediate and 3 hard endosperm), lower protein (10.0 vs. 8.0%), higher nixtamal water uptake after 30 min lime-cooking (50.0 vs. 53.1% moisture) and lower pericarp removal scores. The lower thousand-kernel weight and softer endosperm texture observed in the QPM genotypes lowered the optimum lime-cooking time as estimated with regression equations. Most QPM genotypes had higher amounts of lysine, tryptophan and albumins/globulins when compared with the controls. QPMs HEC 424973, HEC 774986 and HEC 734286 had the best grain traits for nixtamalization and therefore the best potential for industrial utilization. The commercial use of these QPM hybrids should benefit Mexicans who depend on tortillas as the main staple.