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This study investigated the effect of a 50% reduction in sodium nitrite and the addition of nisin (200 mg/kg) and different concentrations (0, 0.5%, 0.75%, and 1%) of jabuticaba peel extract (JPE) on the main attributes affected by this chemical additive in Bologna-type sausages. The modified treatments showed approximately 50% lower residual nitrite than the control throughout the storage (60 days at 4 °C). The proposed reformulation did not affect the color (L*, a*, and b*), and the ΔE values (< 2) demonstrated high color stability during storage. Physicochemical (TBARS and volatile compounds) and sensory analyses performed to evaluate oxidative stability indicated that JPE exhibited antioxidant activity comparable to sodium nitrite. The microbiological quality of the reformulated products was similar to the control, but further studies should be conducted to assess the effect of this reformulation strategy on the growth of pathogenic microorganisms impacted by nitrite.

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Olive pomace oil is obtained when a mixture of olive pomace and residual water is subjected to a second centrifugation. This oil has small amounts of phenolic and volatile compounds compared with extra-virgin olive oil. This study aimed to promote the aromatization of olive pomace oil with rosemary and basil using ultrasound-assisted maceration (UAM) to increase its bioactive potential. For each spice, the ultrasound operating conditions (amplitude, temperature, and extraction time) were optimized through central composite designs. Free fatty acids, peroxide value, volatile compounds, specific extinction coefficients, fatty acids, total phenolic compounds, antioxidant capacity, polar compounds, and oxidative stability were determined. After obtaining the optimal maceration conditions assisted by ultrasound, pomace oils flavored with rosemary and basil were compared to pure olive pomace oil. Quality parameters and fatty acids showed no significant difference after UAM. Rosemary aromatization by UAM resulted in a 19.2-fold increase in total phenolic compounds and a 6-fold increase in antioxidant capacity, in addition to providing the most significant increase in oxidative stability. Given this, aromatization by ultrasound-assisted maceration is an efficient method to increase, in a short time, the bioactive potential of olive pomace oil.

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Pecan nuts, a healthy food, have shown an increased demand for consumption. Therefore, there must be a certain level of care to avoid quality losses, which are primarily influenced by storage conditions and time. This study evaluates the effects of long-term controlled atmosphere (CA) storage with low O2 partial pressure (pO2 - 2 kPa), combined or not with high CO2 (pCO2 - 40 or 80 kPa), carnauba wax coating (CW), and ambient atmosphere (AMB; control) at 10 and 20 °C, on unshelled 'Barton' pecan nut quality. Color, water activity (Aw), moisture content (MC), and oxidation markers, such as peroxide value (PV), acidity value (AV), TBARS, and volatile compounds (VC) were evaluated. Storage up to twelve months at 10 °C and with CA (regardless of the temperature) ensured higher luminosity and color parameter b* ("golden") and a lower a* parameter ("reddish"). The MC ranged from 2.8 to 3.6%, irrespective of storage conditions, for up to twelve months, which is suitable. The AMB at 10 °C ensured lower AV, TBARS, and PV compared to the CW treatment. Furthermore, CA with low pO2 and high pCO2, even at 20 °C, guaranteed lower AV, TBARS, and PV. Storage at 20 °C increased characteristic VCs of lipid oxidation (aldehydes, acids, alcohols, ketones, lactones, and esters, especially with CW coating). However, all conditions at 10 °C and with pCO2 (even associated at 20 °C) reduced the presence of these VCs. The CW used as a coating on the pecans did not show satisfactory results and should not be recommended for pecan storage at these applied conditions. Our findings showed that low pO2 and high pCO2 maintain better pecan quality than O2 ambient (20 kPa), even at temperatures above refrigeration (20 °C). Nevertheless, there were no significant differences between 40 and 80 kPa CO2.

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This study aimed to evaluate the effects of controlled atmosphere (CA) storage at a low oxygen partial pressure (pO2; 2 kPa of O2) and low pO2 associated with high pCO2 (2 kPa O2 + 15 kPa CO2) in relation to ambient atmospheric conditions (control), at different temperatures, on shelled 'Barton' pecan nuts quality after storage. Color, respiration rates, moisture content (MC), and oxidation markers, such as peroxide value (PV), acidity value (AV), and volatile compounds (VC), were evaluated. During six months of storage, the MC decreased in all CA treatments, and treatments at 10 °C had the lowest AVs and PVs. However, the treatment with high pCO2 levels also guaranteed lower AVs at 20 °C. The color parameter b* (yellow), which is related to the golden appearance of pecans and is a highly desirable visual attribute in the commercialization of nuts, was maintained high in treatments at 10 °C with CA treatments until six months of storage. The VCs, characteristic of lipid oxidation (aldehydes, acids, alcohols, and ketones), increase in all treatments with prolonging storage. When pCO2 was associated to 10 °C at six month of storage, it showed a larger area in the acids and unsaturated aldehyde classes, while it was relevant for alcohols, lactones, and esters at 20 °C, with sweet characteristics, including ethyl ethanoate, ethyl hexanoate, and butyrolactone. Thus, this study shows another advance in the storage techniques of shelled pecans, pointing to alternatives for reducing energy costs in the cooling chain.

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The objective of this work was to evaluate the effect of different photo-cycles on the growth and biochemical profile of Scenedesmus obliquus CPCC05, focusing on food interest compounds. The photo-cycle conditions were separated into three groups: long-term photo-cycles (24:0, 22:2, 20:4, 18:6, 12:12, and 10:14 (h:h)), frequency photo-cycles (2, 4, 8, 12, 24, and 48 times per day (t/d)), and short photo-cycles (0.91:0.09, 0.83:0.17, 0.75:0.25, and 0.50:0.50 (s:s)) of light:dark, respectively. The results showed these microalgae can store enough energy to support cell growth for continuous periods of up to 2 h in the dark, without affecting the productivity of the process. This 2 h, when divided into 2 cycles per day (2 t/d), showed the best growth condition (3700 mg L-1), generation time (14.40 h), and maximum biomass productivity (21.43 mg L h-1). This photo-cycle of 2 t/d was also the best condition for the production of total sterols. However, the values of polyunsaturated fatty acids, lipid content, and amino acids obtained higher yields in the short photo-cycle of 0.75:0.25. Thus, the modulation of light cycles becomes an important tool for boosting and directing the production of target molecules in phototrophic cultures of microalgae.

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Apples have a continuous hydrophobic layer that covers the surface of the fruit, which is called the cuticle. The effects of 1-methylcyclopropene (1-MCP) on the cuticular wax layer of apples were reported after cold storage, although the interaction between 1-MCP and dynamic controlled atmosphere (DCA) is not yet known. Therefore, this study aimed to analyze the effects of 1-MCP on the wax composition and metabolism of 'Maxi Gala' apples after storage in a controlled atmosphere (CA) and dynamic controlled atmosphere based on chlorophyll fluorescence (DCA-CF) and respiratory quotient (DCA-RQ; RQ = 1.3 and 1.5). The 1-MCP treatment effectively decreased ethylene production for CA and DCA-CF treatments, while in DCA-RQ treatments produced no effect. The average extracted cuticular wax content of 'Maxi Gala' apples was 16.65 g m-2 and no differences in storage conditions or 1-MCP application were observed. Alkanes, alcohols, fatty acids, aldehydes, and terpenoids were identified in the chemical composition of the cuticular waxes, being alkanes and fatty acids the predominant ones. Moreover, 1-MCP decreased fatty acid and 10-nonacosanol concentrations in the fruit. Fruit with the 1-MCP application and stored in DCA had lower α-farnesene concentrations. The wax compositions of the DCA-stored apples with and without 1-MCP were similar. However, 1-MCP treatment resulted in a greater mass loss in fruit stored in DCA.

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The aim of this study was to evaluate sapota-do-Solimões (Quararibea cordata Vischer) during ripening, verifying physical, chemical and sensory parameters, bioactive and volatile compounds. The pulps were obtained from fruits from the city of Tefé, AM, Brazil and collected at three different ripening stages: unripe (U); ripe collected from the tree (R); and ripe collected from the ground (RG). The biometric and quality parameters, total carotenoids, total phenolic compounds, chemical composition, fatty acids and volatile profiles were analyzed. The sapota-do-Solimões fruits showed positive correlation with evolution of ripened stage of the variables water activity (0.977-0.996), pH (6.53-7.04), soluble solids (8.53-12.65%), total sugars (4.26-7.98%), reducing sugars (0.99-3.14%), non-reducing sugars (3.11-4.60%) and total carotenoids (0.67-1.24 µg/g). Longitudinal and transversal diameters and fruit mass were higher in RG compared with the other ripening stages. The lipids contents increased from 0.16% for U to 0.30% for RG. The palmitic (47.1-86.4), stearic (3.1-5.9), oleic (44.4-131.1) and vaccenic (25.3-37.7) increased while palmitoleic (16.4-10.0) and linoleic (6.6-3.5) decreased. A total of 86 volatile compounds were identified, of which 57 were found in U fruits, 54 in R fruits and 68 in RG fruits. The classes most relevant found were alcohols, aldehydes, esters, ketones, furans and terpenes. An increase in the terpenes (0.4-5.6%) from U fruit to RG fruit showed potentials odoriferous characteristics, as well the increased furans (2.3-20.9%) from U fruit to RG fruit that characterized a sweet and fruity aroma. Consumers didn't detect differences in sensory attributes of the analyzed R and RG fruits. The data showed that the chemical and volatile composition of the fruit was influenced by the ripening stage of the pulp. This is the first time that a study about ripening in sapota-do-Solimões has been reported.

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