Peppers are a very popular ingredient in many dishes, either as the fruit itself or as derived products. They are not only consumed because of their organoleptic characteristics, but also because of their high content of bioactive compounds. The aim of this work was to determine the optimal time to harvest the Bolilla pepper, based on the capsaicinoid concentration in the pericarp and placenta at two different plant maturities (young and adult), in order to maximize their potential biological properties. In the case of the pericarp, the maximum capsaicinoid concentration was reached at 30 days post-anthesis (dpa) (with values of 1565.98 and 2158.82 µmol/kg, for the young and adult plant, respectively), while in the placenta it was registered at 41 dpa with greater values (5898.12 and 2349.67 µmol/kg). In either case, from that moment on, there was a drastic reduction in the capsaicinoid content. With regard to the capsaicinoid content levels in the pericarp, this was greater in older plants, while the placenta presented greater content in younger plants, which is of considerable importance from an economic point of view. This work allows a better selection of the final product, taking full advantage of its beneficial effects on health and taste, which would be very interesting for analytical laboratories or industries.

Barley (Hordeum vulgare L.) is one of the major cereal crops worldwide. It is grown not only to be used as fodder but also for human consumption. Barley grains are a great source of phenolic compounds, which are particularly interesting for their health-promoting antioxidant properties, among other benefits. Two extraction methods, namely ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), have been optimized and compared by using Box–Behnken design (BBD) to determine both the antioxidant power and the phenolic compound levels of the extracts. Three variables have been assessed based on these designs: solvent composition (% MeOH in water), temperature (°C), and sample-to-solvent ratio (mg sample mL−1 solvent). The solvent composition used and the interaction between the solvent and the temperature were the most significant variables in terms of recovery of phenolic compounds and antioxidant capacity of the extracts. Short extraction times, a high precision level, and good recoveries have been confirmed for both methods. Moreover, they were successfully applied to several samples. Significant differences regarding the level of phenolic compounds and antioxidant power were revealed when analyzing three different barley varieties. Specifically, the amounts of phenolic compounds ranged from 1.08 to 1.81 mg gallic acid equivalent g−1 barley, while their antioxidant capacity ranged from 1.35 to 2.06 mg Trolox equivalent g−1 barley, depending on the barley variety. Finally, MAE was found to be slightly more efficient than UAE, presenting higher levels of phenolic compounds in the extracts.