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The modification of the starches aims to change the properties of these polymers making them more suitable for specific applications. Therefore, the objective of this study was to modify potato and rice starch using the hydrolysis process with hydrochloric acid (HCl) and the esterification process with citric acid (CA), both acids at different concentrations and reaction time. To verify if the modifications were effective, the physicochemical changes (solubility, swelling power, gel strength and amylose content), thermal, morphological and pasting properties were evaluated. The applied modifications reduced the swelling power, solubility and amylose content of starches. The strength of the gel was reduced with the modifications for the rice starch and increased for the potato starch. Regarding the pasting properties, modified starch RS1 (modified rice starch using 0.1 M HCl) and PS3 (modified potato starch using 2% CA) showed a tendency to reduce retrogradation. Structurally, X-ray evaluation indicated reduced crystallinity. Thermal analyses showed that gelatinization temperatures were increased for all treatments, while gelatinization enthalpies were reduced indicating greater thermal stability of the modified starches. Therefore, modified starches have distinct characteristics that can be used for specific processes that requiring starches with different properties from the conventional ones.

Active packaging produced from biodegradable polymers and essential oil could have a great value to food industries. This study aimed to evaluate the effect of the addition of oregano essential oil (OEO) on rice starch films and its application as packaging for fish fillets. Several concentrations of OEO were added to the films, the film added with 4.5% OEO showed lower permeability to water vapor 3.7 g mm kPa(−1) m(−2) day(−1), intermediate solubility of 24% and high tensile strength (4.4 MPa) while the standard film (without the addition of OEO) presented 8.8 g mm kPa(−1) m(−2) day(−1), 25.8% and 2.2 MPa, respectively. Packed fish fillets with the active film showed an increase in its shelf life when compared to the standard film. Packaged fish fillets in OEO films showed greater resistance (13.4 N), less oxidation (1.65 mg malonaldehyde/kg of sample) and less microbiological growth 10(7) CFU/g in 6 days of storage, while packaged fish fillets in standard film showed lower resistance (10.4 N), higher oxidation (1.88 mg malonaldehyde/kg of sample) and higher microbiological growth 10(8) CFU/g. Thus, the active packaging developed had the capacity to increase the shelf life of a perishable product that has great interest of food industries. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-020-04668-z) contains supplementary material, which is available to authorized users.

Conventional biosurfactants have high production costs. Therefore, the use of low-cost carbon sources for their production is attractive for industry. The ability to remain stable under various environmental conditions further extends industrial application. Here we aimed to evaluate the stability of a new lipopeptide produced by Corynebacterium aquaticum using fish residue as an unconventional energy source. The biosurfactant was produced using 3% fish residue, 2% of the microorganism, and mineral medium. Biosurfactant characterization was performed by thin layer chromatography (TLC), as well as by testing its infrared, surface tension, emulsifying activity, and ionic character. The stability of the biosurfactant was evaluated by testing its surface tension at a range of temperatures, pH, and saline concentrations, as well as after 6 months of storage. The biosurfactant was characterized as a lipopeptide due to its retention time, which was coincident with the amino acid and lipid chains obtained in the TLC analysis, being confirmed by some regions of absorption verified in the infrared analysis. The surface tension and emulsifying activity of the biosurfactant were 27.8 mN/m and 87.6%, respectively, and showed anionic character. The biosurfactant was stable at temperatures of 20 to 121 °C, in saline concentrations of 1 to 7%, and at pH close to neutrality. Based on our findings, it is possible to use unconventional sources of energy to produce a lipopeptide biosurfactant that can act under various environments.

Biosurfactants are amphipathic compounds formed by a hydrophilic and hydrophobic component, this characteristic confers to these compounds the possibility of several applications. The aim of this study was to produce biosurfactants from different industrials wastes using Corynebacterium aquaticum and Corynebacterium spp. CCT 1968 and study the application in paint removal. The production of biosurfactants was evaluated through surface tension, emulsifying activity and character ionic. The analyses were carried out at 0, 24, 48 h. The biosurfactants that presented lower surface tension and higher emulsifying activity were applied in insoluble paint. The microorganism Corynebacterium aquaticum showed efficient biosurfactant production when using fish and bagasse residues as carbon source. The surface tension obtained for these treatments was 27.8 and 33.9 mN/m and emulsifying capacity was 87.6 and 61.6%, respectively. The Corynebacterium spp. CCT 1968 produced biosurfactants only in the medium containing fish waste (28.5 mN/m). The biosurfactants produced by both microorganisms showed anionic character. The applied biosurfactants showed potential use in solubilization and paint removal. Therefore, the residues of fish and sugarcane bagasse showed efficient as carbon sources to obtain biosurfactants. In addition, the preliminary paint removal application presented great results that can be explored in the future.

Food waste is a great problem nowadays; while many people are starving around the world, tons of food is wasted every day. An efficient way to preserve food is using industrial processes such as heat, cold, drying, fermentation, irradiation, high pressure, pulsed electric fields and modified atmosphere, among others, but it is also possible to use active packaging (AP) to extend the shelf life of food products. This packaging uses active compounds, as antimicrobial and antioxidants that could be released over time in the food and its products and increase their shelf life. Active packaging can be produced from agroindustrial wastes from which it is possible to extract proteins, carbohydrates, and lipids. These materials could be used to develop biodegradable and edible packages. The current chapter discusses existing and innovative packaging solutions to minimize food waste.

Biossurfactantes sao substâncias tensoativas com inumeras aplicacoes. A producao de biossurfactantes a partir de 5, 10 e 15% de soro de queijo foi realizada por Bacillus subtilis e Corynebacterium aquaticum na concentracao de 2% e meio mineral minimo. O cultivo foi realizado a 200 rpm, 30oC por 48 h. Para os residuos de corvina ( Micropogonias furnieri ) foram realizados 2 planejamentos experimentais fatoriais 3 2 , onde foram avaliadas a influencia dos micro-organismos (2%) e a concentracao de pescado 0,83, 1,66 e 2,50%. Um dos planejamentos foi realizado em biorreatores com chicanas e sem chicanas. As condicoes de cultivo foram, agitacao de 200 rpm, 30oC por 72 h. Os cultivos que utilizaram o soro de queijo como substrato obtiveram baixa reducao da tensao superficial. Nos cultivos com residuos de pescado houve reducao da tensao superficial para valores proximos de 24 mN.m -1 nos biorreatores com chicanas e 27 mN.m -1 para os sem chicanas. O melhor resultado foi obtido nos biorreatotes com chicanas onde foi utilizada a concentracao de 0,83% de pescado e o micro-organismo Corynebacterium aquaticum , obtendo 23,74 mN.m -1 de tensao superficial, sendo o valor obtido menor do que valor do biossurfactante mais referenciado na literatura, a Surfactina , que possui tensao de 27 mN.m -1 .