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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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The objective of this study was to evaluate the effect of rosemary essential oil encapsulation using whey protein isolate (WPI) and inulin as encapsulation matrix on the shelf‐life extension of Minas frescal cheese. Essential oil in bulk and microencapsulated forms were added to cheese at concentrations of 0.5% and compared with control treatment (cheese without rosemary essential oil). The aerobic mesophilic microorganism counting cheese with added microencapsulated rosemary essential oil was lesser than that in cheese subjected to other treatments, thus implying that microencapsulated oil has antimicrobial effects. Microencapsulated rosemary essential oil enabled a microbial reduction of 1.36 log cycles after 3 days of storage and 0.73 log cycles after 15 days of storage compared to the control treatment. The microencapsulation process did not alter the chemical composition of the rosemary essential oil and was effective in controlling the acidity of the cheese. Therefore, rosemary essential oil can be used as a potential biopreservative in cheese. Practical Applications Microencapsulation by spray‐drying process maintained the original profile of the bulk rosemary essential oil and the drying process did not alter the oil chemical profile; thus, microencapsulated oil is emerging as a useful alternative for application in the food industry. Essential oil in bulk and microencapsulated forms were added to cheese at concentrations of 0.5% and compared with control treatment (cheese without rosemary essential oil). Microencapsulated rosemary essential oil was able to control the proliferation of mesophilic bacteria in Minas frescal cheese, promoting a delay in the microorganism growth during storage, thereby extending the product shelf life. Thus, the findings of our study show that microencapsulated rosemary essential oil can be used as a potential biopreservative in Minas frescal cheese.

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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.

This work evaluates fresh-cut carrots (FCC) coated with montmorillonite (MMT) subjected to passive modified atmosphere packaging. Carrots were sanitized, cooled, peeled and sliced. Half of the FCC were coated with MMT nanoparticle film and the other half were not. All FCCs were packed in a polypropylene rigid tray, covered with a polypropylene rigid lid or sealed with polyethylene + propylene film, in four treatments (RL, rigid lid; RLC, rigid lid + coating; ST, sealed tray; STC, sealed tray + coating). FCCs were stored at 4 °C and were analyzed weekly for 4 weeks (total antioxidant activity by 2,2-diphenyl-1-picryl hydrazyl method and the β-carotene/linoleic acid, phenolic compounds, organic acids and volatile compounds). The use of coating film with starch nanoparticles and a modified atmosphere leads to the preservation of the total antioxidant activity, the volatile and organic acids of FCC.

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