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A headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC/MS) method was developed to quantify lemon oil components and their degradation products in oil-in-water (O/W) emulsions prepared with sodium caseinate-heated-lactose (NaC-T + Lact) glycoconjugates as wall materials at two pH values (3.0 and 6.8). NaC-T + Lact conjugates had a significantly lower solubility at both pHs. Hydrolysis prior to glycation enhanced the solubility of glycoconjugates. Glycation with lactose did not improve the emulsion activity of NaC, while caseinate glycoconjugates showed much stronger antioxidant activity than the NaC-control sample. This might be due to the presence of melanoidins formed between the sugar and amino acid compounds as supported by the increase in browning intensity. Among the SPME-fibres tested, carboxen/polydimethylsiloxane (CAR/PDMS) provided better results in terms of sensitivity and selectivity for oil lemon components and their degradation products. Storage studies of these emulsions demonstrated that glycated NaC-T + Lact showed protection against peroxidation compared to the control. However, acidic pH conditions altered their stability over storage time. The major off-flavor components (α-terpineol and carvone) were inhibited in emulsions stabilized with glycated NaC, particularly at pH 6.8. The use of NaC-T + Lact conjugates showed improved encapsulation efficiency and stability and could be used as potential food ingredient-emulsifiers for stabilising citrus oils against oxidative degradation in food and beverage applications.

Caryodendron orinocense, Karst., called in Venezuela nogal de Barquisimeto, is an euphorbiaceous tree which grows at the base of the Andes mountains in Venezuela, Ecuador and Colombia, and which has potential as a food source. The fruit is a capsule containing three seeds, with an average weight of 10.2 g for the whole seed or 'nut' and an average weight of the edible portion of 4.9 g. The chemical composition (iron, phosphorus, sodium, potasium, thiamine, riboflavin, ascorbic acid and carotenes) and the antinutritional factors of the whole mature seeds were determined. The seeds presented neither trypsin inhibitors nor haemaglutinating activity. The edible portion contained 33.85% crude fat, and 17.16% protein (N x 6.25) on a dry weight basis and the following amounts of iron, calcium, thiamin and riboflavin: 22.36, 303.91, 0.24 and 0.2 mg/ 100 g, respec tively. These results suggest that the Caryodendron seeds have potential as a source of oil and proteins. Further studies are recommended.