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Introduction: Andean lupin seeds are under-exploited sources of nutrients and bioactive compounds. Materials and methods: seeds were debittered to remove toxic alkaloids, partially defatted with 70% ethanol, dried at 60°C and milled. The defatted flour was suspended in water adjusted at pH 7 with 1N NaOH. The protein extract was filtered and spray-dried. Enriched yoghurts were obtained with the addition of lupin protein concentrate at 0.5, 1 and 1.5%. The chemical and fatty acid composition, the contents of polyphenols and flavonoids as well as the antioxidant activity were determined. The microbial quality and physicochemical properties (pH values, lactic acid content and percentage of syneresis) were evaluated in yoghurts during 28 days of storage. Results: Andean lupin concentrate showed high protein and carbohydrate contents (69% and 20%), unsaturated fatty acids (77%) mainly oleic, linoleic and α-linolenic acids as well as low atherogenic and thrombogenic indexes (0.07 and 0.44). The addition of the lupin protein concentrate at 1.5% into yoghurts increased the protein content. Enriched yoghurts showed higher unsaturated fatty acids, total polyphenol and flavonoid contents as well as lower atherogenic and thrombogenic indexes compared to the control. The lupin protein concentrate increased the ABTS radical scavenging activity, the ferric reducing power and the total antioxidant activity in yoghurts. Enriched and control yoghurts showed similar lactic acid bacterial counts. The counts for total and thermotolerant coliforms were under three MPN/mL and yeast and molds under 10 CFU/ mL. The pH values in enriched products were higher at days 1 and 7 of storage (4.82 and 4.95) compared to the control sample (4.72 and 4.85). The lactic acid content increased in all formulations at day 21. Enriched yoghurts showed lower syneresis than the control. Conclusions: Yoghurts enriched with lupin protein concentrate could represent nutritive and functional alternatives to prevent chronic diseases when consuming in a healthy diet.

In this study it is proposed the introduction of an expansion gas in high pressure water to maximize the cavitation caused by the application of ultrasound to improve the extraction of phenolic compounds from pomegranate peel. Different combinations of ultrasound power (US-Pwr), expansion gas initial pressure (N2-Pi), system pressure (SP) and particle size of sample were evaluated using water as solvent. The use of US-Pwr and N2-Pi individually or combined improved the extraction process proving higher yields. SP was an important parameter affecting extraction yield, showing an inverse relation between its increase and extraction yield. Although higher yields were produced with samples with smaller particles, the combination of ultrasound and expansion gas had a positive effect on the process independently of particle size, promoting an increase of 20-26% in yield. These results suggest an enormous potential to be explored with the introduction of an expansion gas in pressurized liquids in processes assisted by ultrasound for the extraction of phenolic compounds from natural products using green solvents.

The objective of this work was to evaluate the on-line coupling of pressurized liquid extraction with an adsorbent for the simultaneous extraction and separation of flavonols of black tea, producing a concentrated extract that could be used as ingredient for the production of functional bakery products. After the evaluation of different adsorbents, extraction temperatures and solvents, a two-stage process was developed which was capable of producing three extracts: one with high concentration of gallic acid (78.97 ± 5.49 mg/L), another one with high concentration of caffeine (109.72 ± 3.15 mg/L) and a highly concentrated flavonol extract (322.0 ± 4.50 mg/L). The developed method uses greener solvents (water and ethanol) and is capable of producing higher flavonol (~50%) yields than conventional methods. The introduction of the flavonol extract in the dough can be used for the development of functional bakery since compounds were stable under processing conditions.