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UV radiation was combined with the incorporation of fish protein hydrolysates to improve the performance of active bio-based films for food packaging. UV radiation was not used previously to enhance the packaging performance of blend films of starch/protein, and fish protein hydrolysates were not incorporated in bio-based polymer surfaces previously. Rice starch and fish proteins (from Whitemouth croaker muscle) were utilized to prepare films by the casting technique, which were UV-radiated under different exposure times (1, 5, and 10 min). The packaging performance of the films was determined according to the mechanical and barrier performance, solubility, and color. Fish protein hydrolysates (from Argentine croaker muscle) were then incorporated into the films (bulk structure or surface). The results showed that UV radiation for 1 min increased the tensile strength and modified the optical properties of films. It also altered the structure of the polymeric matrix, as demonstrated by the microstructure and thermal analysis, in agreement with the data obtained in packaging properties. The evaluation of antioxidant capacity through 2,2-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and reducing power indicated that incorporating fish protein hydrolysates either in the films’ bulk structure or film surface promoted antioxidant properties; control films (produced with rice starch/fish proteins without hydrolysates) also presented antioxidant potential. According to the peroxide value and thiobarbituric acid reactive substance (TBARS) assays, control films and the films containing hydrolysates in their bulk structure or on the surface could prevent the lipid oxidation of Italian salami. Thus, combining UV radiation to shape the characteristics of bio-based materials with fish protein hydrolysates to reduce lipid oxidation contributes to the performance of active bio-based films for food packaging.

A 60-day feeding trial was conducted to evaluate the effects of including pumpkin seeds and pomace in the diets of Pacific white shrimp Penaeus vannamei, and the effects of these supplements on growth performance, body composition, and total polyphenol, flavonoid and carotenoid contents, as well as on total antioxidant activity, and body color parameters. Five diets were evaluated: pumpkin seeds (PS) at 50 and 100 g·kg−1, pumpkin pomace (PP) at 50 and 100 g·kg−1, and a control treatment. Pacific white shrimp (P. vannamei) juveniles (0.60 ± 0.01 g) were stocked in 15 tanks (310 L), containing 30 shrimps per tank, and the treatments were randomly distributed in triplicate. At the end of the experiment, shrimps were euthanized, weighed, and dissected for further analyses. The inclusion of PS in the diets impaired growth performance, reduced the total flavonoid content and had a pro-oxidative effect on muscle. The inclusion of PP in the diets did not affect growth performance, improved the feed conversion ratio, increased the total flavonoid content in the diets and hepatopancreas, and improved the antioxidant activity of the feeds and shrimp muscle. The total carotenoid content of the feeds increased with the inclusion of PS or PP in the diets; however, the total carotenoid content of shrimp increased only in those fed PP diets. Shrimp fed with PS diets showed a yellowish color and higher saturation when fresh and a reddish color and yellow hue angle after cooking. Shrimp fed PP diets turned reddish and yellowish, both when fresh and after cooking. The inclusion of PS in P. vannamei diets is not recommended; however, PP can be included at 100 g·kg−1 without affecting the growth parameters. Further studies evaluating the inclusion of higher PP levels in shrimp diets are recommended.

Microbial development, enzymatic action, and chemical reactions influence the quality of untreated natural orange juice, compromising its organoleptic characteristics and causing nutritional value loss. Active low-density polyethylene (LDPE) films containing green tea extract (GTE) were previously prepared by a blown film extrusion process. Small bags were prepared from the produced films, which were then filled with fresh orange juice and stored at 4 °C. Ascorbic acid (AA) content, sugar content, browning index, color parameters, pH, total acidity (TA) and microbial stability were evaluated after 3, 7, and 14 days of storage. The packaging containing GTE maintained the microbial load of fresh juice beneath the limit of microbial shelf-life (6 log CFU/mL) for the bacterial growth, with a more prominent effect for LDPE with 3%GTE. Regarding yeasts and molds, only the CO_LDPE_3GTE package maintained the microbial load of fresh juice below the limit for up to 14 days. At 14 days, the lowest levels of AA degradation (32.60 mg/100 mL of juice) and development of brown pigments (browning index = 0.139) were observed for the packages containing 3% of GTE, which had a pH of 3.87 and sugar content of 11.4 g/100 mL of juice at this time. Therefore, active LDPE films containing 3% of GTE increase the shelf-life of fresh juice and can be a promising option for storage of this food product while increasing sustainability.