Cyanogenic glycosides are a large group of secondary metabolites that are widely distributed in the plant kingdom, including many plants that are commonly consumed by humans. The diverse chemical nature of cyanogenic glycosides means that extraction and analysis of individual compounds can be difficult. In addition, degradation can be rapid under appropriate conditions. Amygdalin is one of the cyanogenic glycosides found, for example, in Apples, Apricots and Almonds. We have developed and applied a high performance liquid chromatographic procedure for amygdalin quantification to investigate extraction efficiency and to determine levels in a range of foods. Our results show that seed from Rosaceae species contained relatively high amounts (range 0.1 -17.5 mg/g) of amygdalin compared to seed from non-Rosaceae species (range 0.01 -0.2 mg/g). The amygdalin content of processed fruit products was very low.

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Gluten-free food products are becoming popular due to increased consumers awareness on celiac disease. In this study, novel gluten-free cookies were produced from 100% germinated and non-germinated brown rice flour, and the blend of rice flour with 25% potato starch. The quality of the cookies was evaluated in terms of proximate composition, physical properties (diameters, weights, thickness and spread ratio), textural properties (dough and cookies hardness) and sensory attributes. Results obtained showed that germination increased the protein contents from 7.92% to 7.99%, ash from 1.29% to 1.38%, total dietary fibre from 5.27% to 6.13% and fat from 2.24% to 2.98% in germinated brown rice flour. Germinated brown rice dough and cookies had lower hardness value compared to non-germinated brown rice dough and cookies. Addition of potato starch to germinated brown rice flour increased the lightness (79.1-78.8) and yellowness (24.6-24.2) colour of the cookies, as well as the spread ratio of the cookies (8.28-8.37). Sensory evaluation results showed that all the cookies were similarly rated in terms of appearance, colour, aroma and taste, with cookies containing 75% germinated brown rice flour and 25% potato starch having the highest sensory score for texture (6.63) and overall acceptability (6.90). This study showed that the blend of germinated brown rice flour and potato starch can be used for the preparation of quality and acceptable gluten -free cookies.

The effect of fermentation on physicochemical properties and oxalate content of cocoyam (Colocasia esculenta) flour was evaluated. The cocoyam, white flesh was cleaned, washed, peeled, sliced into chips of 2-2.5 cm thickness, soaked in tap water and left to ferment for 24 h and 48 h. The fermented cocoyam was then drained, dried in cabinet dryer at 60• C for 24 h and milled. The flour samples were passed through a 45 µm mesh size sieve. Unfermented cocoyam flour was also produced and served as a control. Calcium oxalate and some physicochemical properties of flours from the fermented cocoyam were compared with the unfermented flour. Results showed that fermentation effected a significant reduction in oxalate level (58 to 65%) depending on the fermentation period. The amylose content was higher in 48 h fermented flour (55.52%) than in 24 h (54.55%). Pasting (gelatinization) temperature decreased, and water absorption capacity increased markedly due to fermentation.

Recent increase in gluten allergy has led to high demand for gluten free products such as rice pasta. Although rice grains are rich in bioactive compounds and B vitamins, they are generally low in protein compared to wheat grains. The aim of this study was to determine the quality attributes of soy enriched rice pasta. Five Rice-soy pastas were produced from different blends (10–30%) of soybean flour and rice flour. The proximate composition, cooking quality, colour, texture profile, and sensory attributes of the pastas were determined. Results showed increased in protein (6.7–12.1%), crude fibre (0.8–1.3%), ash (0.6–2.2%) and energy values (379–389 kcal/100g). Fortification improved the colour, reduce cooking time (15.59–15.11 min) but increased cooking loss (7.30–7.49%). The hardness (506–314 g), springiness (1.25–0.71 mm) and chewiness (417–334 g x mm) values decreased while gumminess (417–334 g) increased. Rice pasta enriched with 15% soybean flour was highly ranked for sensory attributes. In conclusion, this study demonstrated that Rice-soy pasta can serve as nutritious alternative to conventional rice pasta, and also add variety to food groups for people suffering from celiac disease.

Summary Bambara groundnut is an underutilised African leguminous crop. This study investigated the effect of annealing on the complexing ability and functionality of Bambara groundnut starch with palmitic acid. Corn starch was included as the reference. Annealing created cracks and pores on the surface of Bambara groundnut and corn starches, respectively. Bambara groundnut starch had significantly higher amylose content, higher peak and final viscosities than corn starch. The peak viscosities of native Bambara groundnut and corn starches significantly reduced with palmitic acid addition. Greater reduction in peak viscosities was observed when the annealed starches were complexed with palmitic acid, suggesting that more palmitic acid was complexed after annealing. This was confirmed by XRD peaks and melting enthalpies. Pasting of native Bambara groundnut and corn starches with palmitic acid resulted in the formation of type I V‐amylose complexes, while type II complexes were formed from annealed starches pasted with palmitic acid.