Cellulose at the nanoparticle scale has been studied as a reinforcement for biodegradable matrices to improve film properties. The goal has been to investigate the properties of starch/gelatin/cellulose nanocrystals (CNC) films. Eleven treatments were considered using RCCD (rotatable central composite design), in addition to four control treatments. For each assay, the following dependent variables were measured: water vapor permeability (WVP), thickness, opacity and mechanical properties. The microstructure and thermal properties of the films were also assessed. Increases in gelatin and CNC concentrations lead to increases in film thickness, strength and elongation at break. The films containing only gelatin in their matrix displayed better results than the starch films, and the addition of CNC had a positive effect on the assessed response variables. The films exhibited homogeneous and cohesive structures, indicating strong interactions between the filler and matrix. Films with low levels of gelatin and CNC presented the maximum degradation temperature.

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The use of lignocellulosic raw materials in bioethanol production has been intensively investigated in recent years. However, for efficient conversion to ethanol, many pretreatment steps are required prior to hydrolysis and fermentation. Coffee stands out as the most important agricultural product in Brazil and wastes such as pulp and coffee husk are generated during the wet and dry processing to obtain green grains, respectively. This work focused on the optimization of alkaline pretreatment of coffee pulp with the aim of making its use in the alcoholic fermentation. A central composite rotatable design was used with three independent variables: sodium hydroxide and calcium hydroxide concentrations and alkaline pretreatment time, totaling 17 experiments. After alkaline pretreatment the concentration of cellulose, hemicellulose, and lignin remaining in the material, the subsequent hydrolysis of the cellulose component and its fermentation of substrate were evaluated. The results indicated that pretreatment using 4% (w/v) sodium hydroxide solution, with no calcium hydroxide, and 25 min treatment time gave the best results (69.18% cellulose remaining, 44.15% hemicelluloses remaining, 25.19% lignin remaining, 38.13 g/L of reducing sugars, and 27.02 g/L of glucose) and produced 13.66 g/L of ethanol with a yield of 0.4 g ethanol/g glucose.

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Coffee is one of the most important agricultural products in Brazil. More than 50 % of the coffee fruit is not used for the production of commercial green coffee and is therefore discarded, usually ending up in the environment. The goal of this work was to select an efficient process for obtaining coffee pulp extract and to evaluate the use of this extract in bioethanol production. The effects of heat treatment and trituration on the yield and composition of the extract were investigated by measuring the amounts of reducing sugars, starch, pectin, and phenolic compounds. The extraction process was most efficient at room temperature using grinding followed by pressing. Five different fermentation media were tested: sugarcane juice or molasses diluted with water or with coffee pulp extract and a medium with only coffee pulp extract. Batch fermentations were carried out at 30 °C for 24 h, and samples were taken to obtain measurements of the total reducing sugars, cell count, and ethanol concentration. The addition of coffee pulp extract did not influence the fermentation or yeast viability, and it can thus be mixed with sugarcane juice or molasses for the production of bioethanol, with a yield of approximately 70 g/L.

Pequi, murici and sweet passionfruit are typical fruits from Brazilian Cerrado, which stand out for their sensory attributes such as color, flavor and aroma, in addition to their high nutritional value. Their seeds are by-products from the industrial processing of juices, pulps, jellies, and others, and have great exploitation potential due to their high oil content and the presence of bioactive compounds. The present work aimed to evaluate the chemical composition of pequi almonds, and of murici and sweet passionfruit seeds, and also to quantify the total phenolic compounds, carotenoids, anthocyanins and antioxidant activity by the scavenging activity of •DPPH method. Concerning the chemical composition, pequi almonds presented the highest concentration of lipids (50%), followed by sweet passionfruit (30%) and murici seeds (15%). The almonds from pequi fruit showed the greatest content of protein (33.3%) followed by sweet passionfruit seeds (15%), which presented the highest amount of fiber (41.3%). Murici seeds exhibited the highest content of carbohydrates (46.4%). Pequi almonds had the greatest content of the following minerals, potassium, magnesium, sulfur, manganese, zinc, copper, iron, and sodium, and anthocyanins (14.4 mg CYG/100 g d.b.). Sweet passionfruit seeds presented the greatest amount of calcium, and also had the highest carotenoid content (9 mg/100 g d.b.). Murici seeds showed the highest potential for bioactive compounds, with 404 mg GAE/100 g d.b. and 81% of scavenging activity for the •DPPH. The results demonstrated that the studied seeds have the potential to be sources for new product development, such as oil.

Recently, many researches have become available in order to value agroindustrial waste and by-products through processes that exploit these wastes and transform them into new value-added products. Thus, this study aimed to assess the chemical composition (proximate analysis, mineral profile, pectic substances, carbohydrates), fatty acid profile, and bioactive compounds of two major exotic fruit wastes (seeds), marolo and soursop, largely found in one of the richest Brazilian biomes, the Savannah. Soursop and marolo seeds showed significant fat (295.1 and 311.3 g kg-1 d.b., respectively), protein (149.9 and 188.7 g kg-1 d.b., respectively), and fiber (426.7 and 351.1 g kg-1 d.b., respectively) contents. Marolo seeds were found to be the richest in phenolic compounds (32043.1 mg GAE kg-1 d.b.) and also presented the highest DPPH• scavenging activity (91.25%). The major phenolic compound found in marolo and soursop seeds was rutin. Among the fatty acids found in both seeds, the ones with unsaturated chains were predominant, such as oleic acid (48.54% for marolo, and 40.35% for soursop seeds). The seeds analyzed were found to be sources of Cu and Mg. Marolo and soursop seeds were found to be a good source of nutritional compounds and an alternative to obtain compounds of interest to be used in the development of food produce, pharmaceutical, and cosmetic products.