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The influence of regular air cold storage (7°C and 85 AE 5% RH) followed by ripening at shelf-life conditions (19-21°C and 65 AE 5% RH), on bioactive compounds of Hass avocados was investigated. Results showed that the content of mannoheptulose and perseitol decreased significantly already during cold storage and ripening period. The fatty acid profile and contents of tocopherols (a-and b-tocopherol) and phytosterols (b-sitosterol, stigmasterol, campesterol) remained unchanged from day 0 to edible ripeness. Total phenolics, hydrophilic and lipophilic antioxidant capacity remained unchanged during cold storage and increased during the ripening period. At edible ripeness, significant amounts of phenolic acids, p-coumaric and caffeic and their derivatives were synthesised. Our results demonstrated that regular air cold storage for up to 37 days followed by ripening at shelf-life conditions enhances the phenolic compounds and mainly the hydrophilic antioxidant capacity without affecting the remaining bioactive compounds in Hass avocado.

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Background and objectives Tarwi is a legume that grows in the Andean region of Peru. This grain is characterized by having a high protein content (~42%). In order to generate added‐value products from this resource, the possibility of obtaining tarwi protein hydrolyzates (TPH) with in vitro bioactive properties was evaluated using Alcalase, Neutrase, and Flavourzyme enzymes, acting alone or in combination for up to 240 min. The in vitro evaluated properties were as follows: antioxidant (ABTS assay), antidiabetic (α‐amylase, α‐glucosidase and dipeptidyl peptidase IV (DPP‐IV) inhibition), and antihypertensive (angiotensin‐converting enzyme‐I (ACE) inhibition). Findings The TPH obtained from the different enzyme treatments exhibited important antioxidant, antidiabetic (specially for DPP‐IV inhibition), and antihypertensive properties. One‐stage treatment using Alcalase for 240 min and two sequential stage treatments with Alcalase–Neutrase for 180 min presented the highest ABTS antioxidant activity and lowest IC50 values for DPP‐IV and ACE corresponding to 2.0–1.95 µmol TE/mg, 2.14–2.61 and 0.16–0.11 mg/ml, respectively. Conclusions The results of this research demonstrate that TPH exhibit in vitro multifunctional bioactive properties. Significance and novelty TPH could potentially be used in the prevention or management of chronic diseases related to the development of oxidative processes, diabetes, and hypertension.

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Background and objectives This study investigated the in vitro antioxidant and angiotensin I‐converting enzyme (ACE‐I) inhibitory properties of quinoa (QPH) and kiwicha (KPH) protein hydrolysates. Findings Enzymatic treatments with Neutrase for 120 min for quinoa and sequential Alcalase‐Neutrase hydrolysis for 240 min for kiwicha protein, both at 50°C, presented high antioxidant activities and ACE‐I inhibition (1.50 and 1.67 μmol TE/mg of protein and 89.2 and 72.8%, respectively) and the lowest IC50 values (0.08 and 0.29 mg/ml, respectively). After simulated gastrointestinal digestion (pepsin–pancreatin), both protein hydrolysates did not display significant changes in their antioxidant and ACE‐I inhibition properties. Conclusions The in vitro antioxidant and antihypertensive properties (ACE‐I inhibition) of QPH and KPH obtained via enzymatic hydrolysis using food‐grade commercial enzymes were demonstrated. In addition, tested in vitro bioactive properties did not change after simulated gastrointestinal digestion. Significance and novelty The results of this research might be used to obtain QPH and KPH with bioactive properties and/or as starting material for subsequent processes of separation and purification to obtain bioactive peptides.

The effect of roasting ofPlukenetia huayllabambanaseeds on the fatty acids, tocopherols, phytosterols, and phenolic compounds was evaluated. Additionally, the oxidative stability of the seed during roasting was evaluated through free fatty acids, peroxide, andp-anisidine values in the seed oil. Roasting conditions corresponded to 100, 120, 140, and 160°C for 10, 20, and 30 min, respectively. Results indicate that roasting temperatures higher than 120°C significantly affect the content of the studied components. The values of acidity, peroxide, andp-anisidine in the sacha inchi oil from roasted seeds increased during roasting. The treatment of 100°C for 10 min successfully maintained the evaluated bioactive compounds in the seed and quality of the oil, while guaranteeing a higher extraction yield. Our results indicate thatP. huayllabambanaseed should be roasted at temperatures not higher than 100°C for 10 min to obtain snacks with high levels of bioactive compounds and with high oxidative stability.

Yacon (Smallanthus sonchifolius) root is an important source of fructooligosaccharides (FOS). This study evaluated the influence of the blanching and drying processes on the sugars, FOS and colour of the obtained flour. Blanching in boiling water of 5 mm slices for 6 min allowed to inactivate 95% of polyphenol oxidase and peroxidase activity. Blanching solutions containing ascorbic, citric and lactic acid were detrimental in terms of FOS retention (68.2-87.4%) due to hydrolysis mainly of GF3, GF4 and GF5 FOS, and also important losses of reducing sugars (RS) were observed (69.5-87.4% retention). Blanching treatments that included ascorbic acid/CaCl 2 prevented RS and FOS losses and improved colour of the obtained flour. The drying tested temperatures of 50-80°C did not affect the RS retention and FOS losses associated to hydrolysis and the use of 80°C rapidly reduced the water content and minimised browning reactions yielding flours with excellent colour characteristics with high FOS content that can be derived to the elaboration of prebiotic containing functional foods or for the extraction and purification of FOS. Drying process evaluationAfter optimisation of the blanching process described above, different drying temperatures were tested that corresponded to 50, 65 and 80°C, respectively, under the same conditions described above. For each corresponding drying temperature, a not blanched control sample was obtained. All treatments were carried out in triplicate. Analysis carried out included water content, RS, FOS and colour. Analytical determinationsWater content was determined in a vacuum oven until constant weight was obtained according to the 925.45-A method (AOAC, 1995). The pH of the blanching solutions and obtained flours was carried out