This study focuses on optimizing the ultrasound-assisted extraction (UAE) of bioactive compounds from purple-fleshed sweet potatoes (PFSP) for potential use as natural colorants. Factors such as time, temperature, and solid-to-liquid ratio were varied using a Box–Behnken Design. The optimal conditions were determined as 75 min, 70 °C, and a 1:15 m/v solid-to-liquid ratio, resulting in 18.372 mg/100 g total anthocyanin (TA) and 151.160 mg GAE/100 g total phenolic content (TPC). The validation yielded 18.822 mg/100 g for total anthocyanin and 162.174 mg GAE/100 g for total phenolic content, showing a 7% difference from predictions. UAE significantly increased TA extraction by 81% and TPC by 93% compared with the conventional method, with a notable reduction in process time from 24 h to 75 min. Additionally, three kinetic models were tested to compare extraction mechanisms, confirming the efficiency of UAE for PFSP bioactive compound recovery. This study proposes the UAE technique as a highly effective means of extracting bioactive compounds from PFSP, offering promising applications across multiple industries.

Cocoa beans contain a variety of nutritional compounds and are rich in biologically active substances. The aim of this study was to utilize cocoa nibs (roasted and unroasted) as the main ingredient in the development of an attractive and convenient product. The produced nibs were analyzed for total phenolics, flavonoids, and antioxidant capacity using DPPH, ABTS, and FRAP methods. The primary phenolic compounds and methylxanthines were analyzed by LC/MS. Subsequently, cereal bars were developed, including a control sample (without nibs) and five formulations containing 41% nibs, using various proportions of roasted and unroasted nibs. The influence of the origin of the beans on the product characteristics was also evaluated. The results showed that the roasting process led to a reduction in epicatechin, caffeine, and caffeic acid. Furthermore, the reduction in total phenolics, flavonoids, and antioxidant capacity after roasting was more pronounced in beans from Bahia compared to those from Espírito Santo. Regarding the cereal bars, the results demonstrated that using cocoa from Bahia, the formulation with a higher proportion of unroasted nibs (F80) significantly increased the total phenolic content (1968.85 mg of gallic acid/100 g) and total flavonoids (39.26 mg of quercetin/100 g). This initial study suggests that the use of cocoa nibs as a functional ingredient in cereal bars may be a viable and advantageous option for creating a product with greater antioxidant potential.