RESUMO
The jerivá (Syagrus romanzoffiana) and the macaúba (Acrocomia aculeata) are palm trees of the Arecaceae family, widely distributed in tropical and subtropical areas of Latin America, which have a low production cost and high productivity throughout the year. Due to the high content of lipids, their fruits have been used for oil extraction, which generates byproducts such as the pulps and the kernel cakes, a nutritionally rich byproduct that can be added into human food and, may have prebiotic potential. Therefore, the objective of this work was to characterize and evaluate the prebiotic potential of jerivá pulp (JP), macaúba pulp (MP), jerivá kernel cake (JC) and macaúba kernel cake (MC). For this, the fruits characterization was carried out through proximate composition, phenolic compounds content, and antioxidant activity, besides evaluating the antimicrobial and fermentative capacity of Bifidobacterium lactis, Lactobacillus casei, and Lactobacillus acidophilus against Escherichia coli. Jerivá and macaúba pulps and kernel cakes presented high levels of dietary fiber (20.45% JP, 37.87% JC, 19.95% MP and 35.81% MC) and high antioxidant activity, especially JP, which also showed the high values found for ABTS and DPPH (2498.49 µMTrolox·g-1 fruit and 96.97 g fruit·g-1 DPPH, respectively), has a high total phenolic content (850.62 mg GAE·100 g-1). Also, JP promoted a better growth of probiotic strains and a more relevant pH reduction when compared to the commercial prebiotic FOS. However, MP, JC, and MC were also able to favor the growth of the strains. Probiotic microorganisms were able to use JP, MP, JC, and MC and produced short-chain fatty acids such as lactic, propionic, butyric, and acetic acid, capable of promoting health benefits. Therefore, the byproducts from jerivá and macaúba oil extraction have characteristics that indicate their prebiotic potential, and maybe interesting components to increase the nutritional value of foods.
Assuntos
Arecaceae , Frutas , Antioxidantes/análise , Frutas/química , Humanos , Valor Nutritivo , PrebióticosRESUMO
Macauba (Acrocomia aculeata) kernel oil is rich in short- and medium-chain saturated and unsaturated fatty acids, the most abundant of which are lauric and oleic acids. The oil also has high oxidative stability and contains bioactive compounds. Like other oils rich in lauric acid, Macauba kernel oil is solid at low temperatures but has a low solid fat content at room temperature. The hypothesis of this study is that the thermal and textural characteristics of Macauba kernel oil can be modified by fractionation. Fractions were obtained and analysed with respect to their fatty acid profile, oxidative stability, crystallization and melting profile, firmness and physical state at different temperatures. The fatty acid profiles of the fractions remained virtually unchanged, but the oxidative stability of stearins was greater than that of oleins. An increase in the percent enthalpy of crystallization and melting at lower temperatures was observed in oleins, with a consequent decrease in solid fat content, firmness and oxidative stability (compared with stearins) without a relevant change in the fatty acid profile, suggesting that triacylglycerols with unsaturated fatty acids were prevalent in positions sn1 and sn3 in oleins and in position sn2 in stearins. Thus, it was possible to obtain an olein with 26% less solid fat at 25 °C that was 22% less firm and that remained liquid until 3 °C below the oil, as well as a 23% firmer stearin.