Produção de extrato da amêndoa da castanha de caju em pó e incorporação em iogurte.

Abstract

The water-soluble extract of cashew nut almond is a product rich in proteins and lipids, with excellent flavor and high added value. Transformed into powder, it maintains its best characteristics and acquires the advantages of mass and volume reduction, in addition to becoming suitable for nutritional and sensory enrichment of other products to which it is incorporated. The objective of this work was to produce hydrosoluble extract of cashew nut almonds (HECNA) and convert it into powder after drying by three methods: convective drying, freeze drying and spray drying; evaluate the physical, physical-chemical and functional properties of the liquid extract and the powder extract; prepare yoghurts formulated with the addition of powder extract in different concentrations and evaluate it under cold storage conditions. To obtain the HECNA, the cashew nut almonds (CNA) were crushed in a 1:6 ratio (almond: water), then the mixture was sieved to separate the HECNA from the residue. The cashew nut almonds and the water-soluble extract were characterized according to the parameters of water content, water activity, color, proteins, lipids, total soluble sugars, reducing sugars, non-reducing sugars, ash, pH, total titratable acidity, ascorbic acid , fatty acid profile; in powder extracts the same analyzes were carried out and the yield and mineral profile were determined; hygroscopicity, apparent density, compacted density, Carr index (CI), Hausner factor (HF), angle of rest, solubility and morphology. In convective drying, a drying kinetics study was carried out at temperatures of 50, 60, 70 ° C and the Diffusion Approximation, Two Term Exponential, Two Terms, Logarithmic, Henderson and Pabis, Page and Lewis models were adjusted to the data experimental. Lyophilization was carried out for a period of 72 hours at a temperature of -55 oC and spray drying performed at temperatures of 150, 170 and 190 oC. The water adsorption isotherms in the powder extracts were determined at 25 oC and the models of GAB, Peleg, Oswin, Henderson, Halsey and Smith were adjusted to the experimental data. The powder with the highest lipid content, the best fatty acid profile, the best CI and HF values, that is, greater fluidity and less cohesiveness, was selected to be used in yogurt formulations, which were prepared with the selected powder extract, consisting of: F1 - control, 0% addition; F2 - with the addition of 5% of the powdered extract; F3 - addition of 10% of the powdered extract; F4 - with the addition of 15% of the powdered extract. The yogurts were stored at 5 ° C for 28 days, evaluating the pH, total titratable acidity, proteins, lipids, water retention capacity and syneresis. Lipids and proteins stood out as major constituents in CNA and HECNA. The main fatty acid that makes up the lipids in CNA and HECNA is oleic acid, corresponding to about 61% of total fatty acids. The Diffusion Approximation model was the one that best fitted the experimental data of the drying kinetics of the HECNA; and the Peleg model was the one that best fitted the water adsorption isotherms of the powder extracts. At the end of the storage of the yoghurts, all formulations presented values of pH, acidity, proteins close to the beginning of storage; the water holding capacity has decreased; the F4 yoghurt showed greater gel stability, less whey separation and higher apparent viscosity during storage.