There are two types of milk whey obtained from cheese manufacture: sweet and acid. It retains around 55% of the nutrients of the milk. Milk whey is considered as a waste, creating a critical pollution problem, because 9 L of whey are produced from every 10 L of milk. Some treatments such as hydrolysis by chemical, fermentation process, enzymatic action, and green technologies (ultrasound and thermal treatment) are successful in obtaining peptides from protein whey. Milk whey peptides possess excellent functional properties such as antihypertensive, antiviral, anticancer, immunity, and antioxidant, with benefits in the cardiovascular, digestive, endocrine, immune, and nervous system. This review presents an update of the applications of milk whey hydrolysates as a high value-added peptide based on their functional properties.

Films from three different bloom strength were prepared and dried at three different temperatures (20 8C, 40 8C and 60 8C) to investigate whether the differences in ordering and aggregation during film formation, under controlled drying conditions, reflect changes in their mechanical properties. Results showed that Young's modulus (E) was not significantly (p 0.05) influenced by the drying regime because it remained around 3.0 GPa. Film A-270 dried at 20 8C showed higher fracture properties when compared with the same sample dried at 40 8C and 60 8C. Brittleness followed: 60 8C 4 40 8C 4 20 8C. A-100 was sensitive to 60 8C because there was no formation of a continuous network. Films with higher bloom index showed improved fracture properties, it followed A-270 4 A-160 4 A-100. Films reflected lower degree of crystallinity (*0%) as the drying temperature increased; the higher the crystallinity (*33%), the better the fracture properties. Films formed at 40 8C and 60 8C showed mostly an amorphous structure.Keywords: gelatin; film; fracture properties; Young's modulus; drying temperature; crystallinity Pelı´culas con tres diferentes grados de firmeza de gel fueron elaborados y secados a tres diferentes temperaturas (20 8C, 40 8C y 60 8C) para investigar si las diferencias en reorganizacio´n y agregacio´n durante la formacio´n de pelı´cula bajo condiciones de secado controladas refleja cambios en sus propiedades meca´nicas. Los resultados mostraron que el mo´dulo de Young (E) de las pelı´culas no fue influenciado significativamente (p 0,05) por el re´gimen de secado debido a que e´ste permanecio´alrededor de 3,0 GPa. La pelı´cula A-270 secado a 20 8C mostro´mejores propiedades de fractura en comparacio´n a la misma muestra pero secada a 40 8C y 608. La rigidez en pelı´culas siguio´la tendencia: 60 8C 4 40 8C 4 20 8C. A-100 fue sensitiva a 60 8C porque no hubo formacio´n de una red continua. Las pelı´culas con alto nivel de firmeza de gel mostro´mejores propiedades de fractura, esta tendencia mostro´A-2704A-1604A-100. Las pelı´culas reflejaron bajo grado de cristalinidad (*0%) mientras que la temperatura de secado se incrementaba, cuanto ma´s alta la cristalinidad (*33%) mejores fueron las propiedades de fractura. Pelı´culas formadas a 40 8C y 60 8C mostraron una estructura amorfa.

The extraction of lycopene was carried out with three types of vegetable oils (grape, extra virgin olive, and peanut) by means of two methods: agitation and high-intensity ultrasound with a frequency of 20 kHz at an amplitude of 80% with periods of 40 s of sonication for 20 min at a temperature of 40 °C. The antioxidant determination by inhibition of ABTS and DPPH radicals showed no significant differences (p > 0.05) for inhibition of the ABTS radical in native oils and oils with lycopene. However, the radical DPPH showed that the native oils presented significant differences (p ≤ 0.05) compared to the samples with lycopene. FTIR spectra revealed the characteristic functional groups of lycopene exhibiting two characteristic peaks at 2923 cm−1 and 2957 cm−1. The DSC thermograms showed that the higher the degree of oil unsaturation, the lower the melting temperatures. Olive oil was the least unsaturated with the highest amount of oleic fatty acid. Grapeseed oil reported the lowest melting temperature at around −24.64 °C. Extra virgin olive oil showed the lightest values (L* = 41.08 ± 0.45) of brightness, and the peanut oil with lycopene was the darkest (L* = 16.72 ± 0.05). The extraction of lycopene from organic wastes treated with agitation and ultrasound was satisfactory reducing the use of conventional solvents. However, extraction with olive oil under agitation showed the best results.

Waste generated from the agro-food industry represents a concerning environmental, social and economic issue. The Food and Agriculture Organization of the United Nations defines food waste as all food that decreases in quantity or quality to the extent that it is thrown out by food service providers and consumers. The FAO reports that 17% of worldwide food production may be wasted. Food waste may include fresh products, food close to the expiration date discarded by retailers and food products from household kitchens and eating establishments. However, food waste offers different possibilities to extract functional ingredients from different sources, such as dairy, cereals, fruits, vegetables, fibers, oils, dye and bioactive compounds. The optimization of agro-food waste as an ingredient will help in the development and innovation of food products to generate functional food and beverages to prevent and treat several diseases in consumers.

Silver nanoparticles were successfully synthesized using Thuja orientalis aqueous extract and AgNO3 as a precursor. UV–Vis showed a distinct absorption peak at 424 nm attributed to silver nanoparticles due to their surface plasmon resonance. Atomic absorption analysis reflected an increase in the concentration of nanoparticles in relation to the progress of the synthesis, obtaining a peak concentration value of 15.7 mg/L at 50 min. The FTIR spectra revealed the characteristic functional groups of phytomolecules involved in the silver–ion binding process, such as R–O–H (3335 cm−1) O=C–OH (2314 cm−1) and C—C=C (1450 cm−1). At 50 min, zeta potential showed the stability of the nanoparticles with the value of −21.73 mV. TEM micrographs revealed the formation of spherical nanoparticles with an average size of about 85.77 nm. Furthermore, films incorporated with nanoparticles exhibited a Tg from 66.42 °C to 73.71 °C and Tm at 103.31 °C. Films from the G22 formulation presented excellent antibacterial properties inhibiting the growth of Staphylococcus aureus. Thuja orientalis aqueous extract could be a low-cost, eco-friendly, and efficient reducing and capping agent for the synthesis of nanometric-sized Ag particles. Gelatin films with nanoparticles are expected to have high potential as an active food packaging system.