The effect of irradiation (dose levels of 0, 2.5, 5, 10 and 20 kGy) on nutritive (amino acids, and protein digestibility) and anti-nutritional characteristics [total phenols (PH), tannins (TA), phytic acids (PA) and oxalate (OX)], level of anti-nutrients in vitro digestibility (IVPD) and protein digestibilty corrected amino acid score (PDCAAS) of sorrel seeds (Hibiscus sabdariffa) , were examined. The results showed that amino acids content were significantly (p < 0.05) enhanced by the irradiation up to the dose of 10 kGy in comparison with the control sample. Radiation processing significantly (p < 0.05) reduced the levels of total phenols, tannins, phytic acids and oxalate. IVPD and PDCAAS were significantly enhanced in a dose- dependent manner, relative to unirradiated control sample. The data sets for each dose level exhibited high correlation coefficient between dose and PH, TN, PA, OX and IVPD. We conclude that the overall dose of 10 kGy is very effective for hygienation and quarantine purposes and does not adversely affect the nutritional quality of sorrel seeds.

The potential use of quality protein transgenic maize (genetically modified maize with the cDNA of amarantin) for preparation of flour and tortillas through an extrusion lime cooking process was investigated. Tortillas from extruded transgenic maize flour had similar physicochemical and sensory properties than those from the commercial brand MASECA™; however, the former had the highest (P < 0.05) protein content (12.91 vs 8.93%, db), essential amino acids content, calculated protein efficiency ratio (C-PER; 2.27 vs 0.90) and protein digestibility corrected amino acid score (PDCAAS; 55.54 vs 30.18%) and therefore they were nutritionally better. The use of transgenic maize for flour and tortilla preparation through an extrusion lime cooking process may have a positive impact on the nutritional status of people from countries where maize is the basic staple food. It also represents an alternative process to nixtamalization that requires little energy and water, it does not generate wastewater, and all components of the maize kernel are retained.

Poster Reference Number: PO2580 | Background and objectives: Portugal has the largest consumption of rice 15.8 kg/capita/year, in Europe. The present work aims to evaluate: rice nutritional profile, namely proximate, amino acid and mineral composition; arsenic content, as the most abundant contaminant and, compositional differences between varieties, year and place of harvest. Methods: Samples were collected from the most representative national rice producers. Analysis was carried out by following analytical methods: proximate by AOAC methods; amino acids by UPLC-DAD; starch, and amylase by enzymatic methods; mineral analysis by ICP-OES including copper, manganese, iron, zinc, magnesium, calcium, sodium, phosphorus and potassium and arsenic content by ICP-MS. Results: Analyzed rice showed higher amylopectin (54.7 ± 7.3 g/100g) content than amylose (33.5± 3.8 g/100g) and total protein content of 7.1 ± 0.3 g/100g a low content of fiber and fat (<1 g/100 g) was found. The most abundant essential amino acids were aromatic amino acids with a 7.5% of total protein. The most abundant minerals were potassium and phosphorus with levels ranging from 91 mg/100g to 107 mg/100g.The arsenic content was determined by ICP-MS and the values were below 600 µg/kg. Conclusions: Crop place showed to be the major source of variation in amino acid content. With respect to protein quality, cysteine, lysine, sulfur amino acids and isoleucine were considered limiting with protein digestibility corrected amino acids scores (PDCAAS) lower than 1. To assure the nutritional requirements for amino acids and subsequent protein synthesis, rice consumption must be followed by other food groups (e.g pulses, meat products) in order to provide the other essential amino acids. Rice contribution for mineral intake ranged from 3% DRI (iron and potassium) to 36 % DRI (manganese). In this study, a very weak correlation between arsenic levels and amino acid content was observed.