SmartAnalysis: A sustainable digital-image colorimetry method for ethanol determination in alcohol-based hand sanitizer / SmartAnalysis: Un método sostenible de colorimetría de imagen digital para la determinación de etanol en desinfectante de manos a base de alcohol

Introducción: El consumo de desinfectantes de manos a base de alcohol ha aumentado significativamente después de la pandemia causada por el SARS-CoV-2. A pesar de la conclusión de la emergencia sanitaria declarada por la OMS en 2023, la costumbre de desinfectar las manos con geles sanitizantes a base de etanol ha sido adoptada a nivel mundial por la población. Dado que los métodos generales descritos en los compendios oficiales para la de-terminación del etanol, como la cromatografía de gases o la destilación, son laboriosos y no específicos para geles que contienen carbómero, este trabajo propone un método alternativo basado em la colorimetría de imágenes digitales. Método: La imagen digital (proporcionada por la reacción etanol-fenolftaleína) fue capturada y transformada en una señal analítica basada en el sistema de colores Rojo-Verde-Azul. Las adquisiciones de imágenes se realizaron utilizando un smartphone Samsung Galaxy J6, y las señales se generaron mediante el programa gratuito Photometrix Pro®. El método fue validado de acuerdo con las directrices de la ICH y se aplicó en muestras comerciales. Además, el método propuesto fue evaluado por su impacto ambiental utilizando la herramienta Índice del Proceso Analítico Verde (GAPI). Se generaron pictogramas utilizando el programa gratuito ComplexGAPI®.Resultados: El canal verde mostró una respuesta lineal en las curvas de calibración para concentraciones de etanol que van desde el 5 hasta el 40 % (p/p) en medio ácido. El método demostró linearidad, precisión, exactitud y robustez. Conclusiones: El método propuesto presentó como principales ventajas el uso de dispositivos de bajo costo y fáciles de manejar, así como un consumo reducido de reactivos, de acuerdo con los principios de la química analítica verde. (AU)

Introduction: The consumption of alcohol-based hand sanitizers has increased significantly after the pandemic caused by SARS-CoV-2. Despite the conclusion of the health emergency declared by the WHO in 2023, the habit of sanitizing hands with ethanol-based gel sanitizers has been globally adopted by the population. Since general methods described in official compendia for ethanol determination such as gas chromatography or distillation are laborious and not-specific to carbomer-containing gels, this work proposes an alternative method based on digital image colorimetry. Method: The digital image (provided by ethanol-phenolphthalein reaction) was captured and transformed into an analytical signal based on the Red-Green-Blue system. The image acquisitions were performed using a Samsung Galaxy J6 smartphone, and the signals were generated using the Photometrix Pro® free program. The method was validated in accordance with ICH and applied in commercial samples. Additionally, the proposed method was eval-uated for its environmental impact using the Green Analytical Process Index (GAPI) tool. Pictograms were generated using the ComplexGAPI® free program. Results: Green channel exhibited a linear response in the calibration curves for ethanol concentrations ranging from 5 to 40 % (w/w) in acidic medium. The method showed linearity, precision, accuracy, and robustness. Conclusions: The proposed method presented as main advantages the use of low-cost and easy-to-handle devices and reduced reagent consumption, in accordance with green analytical chemistry principles. (AU)

Green technologies applied to low-NaCl fresh sausages production: Impact on oxidative stability, color formation, microbiological properties, volatile compounds, and sensory profile.

The influence of different concentrations of NaCl (2.5% and 1.75%), basic electrolyzed water (BEW), and ultrasound (US, 25 kHz, 159 W) on the quality of fresh sausages was studied. During storage at 5 °C, TBARS, pH, Eh, aw, nitrous pigments, and bacterial evolution were evaluated at three specific time intervals: 1d, 15d, and 30d. At the same time, the volatile compounds and sensory profile were specifically assessed on both the 1d and 30d. Notably, sausages with 1.75% NaCl and BEW displayed higher pH values (up to 6.30) and nitrous pigment formation, alongside reduced Eh (as low as 40.55 mV) and TBARS values (ranging from 0.016 to 0.134 mg MDA/kg sample), compared to the 2.5% NaCl variants. Protein content ranged between 13.01% and 13.75%, while lipid content was between 18.23% and 18.86%, consistent across all treatments. Psychrotrophic lactic bacteria showed a significant increase in low-NaCl sausages, ranging from 5.77 to 7.59 log CFU/g, indicative of potential preservative benefits. The sensory analysis favored the TUSBEW70 treatment for its salty flavor on the 30th day, reflecting a positive sensory acceptance. The study highlights that employing US and BEW in sausage preparation with reduced NaCl content (1.75%) maintains quality comparable to higher salt (2.5%) counterparts. These findings are crucial for meat processing, presenting a viable approach to producing healthier sausages with reduced sodium content without compromising quality, aligning with consumer health preferences and industry standards.

Jabuticaba peel extract and nisin: A promising combination for reducing sodium nitrite in Bologna-type sausages.

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.

Do ultrasound form spontaneously nitrous pigments in nitrite-free pork meat batter?

The effects of ultrasound (US) on myoglobin modification, nitrous pigment formation, color, and total and free sulfhydryl content in nitrite-free pork meat batter were assessed. Five treatments were elaborated: Control (without US); TUS10'12 and TUS20'12 (sonication at 25 kHz, at 12 °C for 10 and 20 min, respectively); TUS10'18 and TUS20'18 (sonication at 25 kHz, at 18 °C for 10 and 20 min, respectively). Sonication for 20 min at 12 °C increased OxyMb and DeoxyMb pigments while reducing MetMb levels. This US condition also yielded higher red color indices and lower yellow color indices. Moreover, TUS20'12 exhibited enhanced nitrous pigment formation and decreased FerrylMb and free sulfhydryl (SH) values, indicating reduced oxidation in OxyMb and DeoxyMb pigments. In conclusion, the findings demonstrate that US can impart a cured color to nitrite-free meat products.

Raspberry Extract as a Strategy to Improve the Oxidative Stability of Pork Burgers Enriched with Omega-3 Fatty Acids.

Hydrogelled emulsions (HEs) of linseed oil and pea protein (PP) were produced with four levels (0, 5, 7.5, and 10%) of raspberry extract obtained by a green extraction technique (microwave hydrodiffusion and gravity-MHG). HEs were applied in burgers to replace 50% of pork backfat content. The products' technological, nutritional, oxidative, microbiological, and sensory properties were evaluated. Besides reducing the fat level by approximately 43%, the reformulation reduced the n-6/n-3 PUFA ratio to healthy levels, decreased the diameter reduction by 30%, and increased the cooking yield by 11%. Including 7.5 and 10% of raspberry extract in the HEs decreased the oxidative defects caused by the enrichment of the burgers with omega-3 fatty acids. In addition, the raspberry extract did not cause alterations in the mesophilic aerobic count and the burgers' sensory profile.

Carcass traits and meat quality of lambs slaughtered during different seasonal conditions.

This study was conducted to evaluate the effects of slaughtering feedlot Texel lambs during different climatic conditions on carcass and meat quality traits. Twenty castrated male Texel lambs (21.8 ± 0.62 kg) were distributed to two treatments according to the climatic conditions during the finishing period and at pre-slaughter: warm season (WS; mean temperature of 23.4 °C and 77.5% relative humidity) and cool season (CS; mean temperature of 14.9 °C and 79.5% relative humidity). During the pre-slaughter, thermal comfort was evaluated through the variables: respiratory frequency, rectal temperature, temperature of the ocular region, and temperature-humidity index (THI). After the finishing period, lambs were slaughtered, and carcass and meat quality traits were assessed. The THI values indicate that animals harvested in the WS spent 13 h of the day under potential thermal discomfort conditions in the week before slaughter and in the pre-slaughter period, whereas lambs harvested in the CS did not experience any thermal discomfort. Slaughter weight, carcass weight, carcass dressing, and backfat thickness were greater (P ≤ 0.03), whereas cooling losses were lower (P < 0.01) for lambs slaughtered in the CS. Moreover, thawing losses were lower (P < 0.01), whereas cooking losses were greater (P < 0.01) for lambs harvested in the CS. Lambs slaughtered in the CS also showed greater meat redness, yellowness, and chroma values (P < 0.05). Although carcass traits were affected by the greater thermal discomfort exposure, meat quality of lambs was less impacted by the climatic conditions at slaughter.

Food potential of Scenedesmus obliquus biomasses obtained from photosynthetic cultivations associated with carbon dioxide mitigation.

Microalgae are photosynthetic microorganisms that stand out from conventional food sources and ingredients due to their high growth rate and adaptability. In addition to being highly sustainable, significant concentrations of proteins, lipids, and pigments accumulate in their cell structures from photosynthesis. Hence, this study sought to evaluate the food potential of Scenedesmus obliquus biomasses obtained from photosynthetic cultures enriched with 3, 5, 10, 15, 20, and 25% carbon dioxide (CO2) (v/v). Cultivations with 3, 5, and 10% CO2 showed greater amino acids and proteins synthesis; the protein content reached values above 56% of the dry biomass and high protein quality, due to the presence of most essential amino acids at recommended levels for the human diet. The highest concentrations of chlorophylls were found in cultures with 15, 20, and 25% CO2 (24.2, 23.1 and 30.8 mg g-1, respectively), although the profiles showed higher percentages of degradation compounds. Carotenoid concentrations were three times higher in cultures with 3, 5, and 10% CO2 (25.3, 22.7 and 18.1 mg g-1, respectively) and all-trans-ß-carotene was the major compound. Lipid synthesis was intensified at higher CO2 enrichment; the percentages obtained were 14.8% of lipids in the culture with 15% CO2, 15.0% with 20% CO2, and 13.7% with 25% CO2. In addition, greater polyunsaturated fatty acids accumulation and a significant reduction in the n6/n3 ratio were also observed at the highest CO2 concentrations. Our findings showed that CO2 treatments significantly altered all compounds concentrations in S. obliquus biomasses, which presented satisfactory composition for application in foods and as ingredients.

Effect of ultrasound application on the growth of S. xylosus inoculated in by-products from the poultry industry.

A wide variety of by-products are produced by the industry when animals are slaughtered. However, the proteins present in these by-products, are not being fully useable, in the elaboration of value-added products. Staphylococcus xylosus is commonly used as a starter culture in meat products subjected to ripening for a long period, as it produces proteolytic and lipolytic enzymes that improve the sensory quality of the products. Ultrasound (US) has been arousing interest in the meat industry, as it reduces processing time and also improves the technological and sensory quality of meat products. However, the stimulate effect of US on the growth of S. xylosus in by-products from the poultry industry is still unknown. Thus, this study aimed to evaluate the stimulate effect of US on the growth of S. xylosus inoculated in by-products from the poultry industry. S. xylosus was inoculated (5.63 log CFU/g) in sterilized by-products from the poultry, which were then sonicated at 37 °C for 0, 15, 30, and 45 min according to the following parameters: frequencies of 130 and 35 kHz, amplitudes of 50% and 80% and normal and degas operating modes. The sonicated samples were incubated at 37 °C for 0, 24, 48, and 72 h. Soon after sonication, no stimulate effect of US was observed on the growth of S. xylosus. However, after 24 h of incubation, the samples sonicated for 15 and 30 min in normal mode, at 35 and 130 kHz, and amplitudes of 50 and 80% exhibited better stimulate effect at the growth S. xylosus counts (p < 0.01) when compared to the Control, with values of 8.23 and 7.77 log CFU/g, respectively. These results can be exploited to obtain new added-value products, having as raw material by-products from the poultry industry.

Combined effect of ultrasound and basic electrolyzed water on the microbiological and oxidative profile of low-sodium mortadellas.

Ultrasound (US) and basic electrolyzed water (BEW) are considered emerging technologies; however, few studies have addressed the combination of both technologies in emulsified meat products. This study aimed to evaluate the individual and combined effect of US (25 kHz; 175 W; 20 min) and BEW (pH 10.99; -92.33 mV) on the microbiological and oxidative profile of low-sodium mortadellas (30% of NaCl reduction) stored for 90 days at 5 °C. The use of BEW alone increased the pH and reduced the redox potential of mortadellas, while the US did not affect these parameters. The combined application of US and BEW reduced the lactic acid bacteria counts by up to 0.36 log CFU/g. In addition, BEW stimulated the growth of lipolytic bacteria. The treatments subjected to US application alone showed a lower growth rate of lipolytic bacteria, lower lipid and protein oxidation, and higher ΔE* values. Therefore, the application of US and BEW may be a promising strategy to improve the microbiological and oxidative quality of mortadella during storage.

The isolated or combined effects of dynamic controlled atmosphere (DCA) and 1-MCP on the chemical composition of cuticular wax and metabolism of 'Maxi Gala' apples after long-term storage.

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.

Green microsaponification-based method for gas chromatography determination of sterol and squalene in cyanobacterial biomass.

Sterol analysis of complex matrices can be very laborious. To minimize the existing drawbacks, a new micro-method of sterols and squalene determination in cyanobacteria was developed and applied to monitor their production of Phormidium autumnale cultured heterotrophically. Sample extraction/saponification and GC analysis of the target compounds were optimized separately using Plackett-Burman design (PB) followed by a central composite rotational design (CCRD). The most influential variables were identified to maximize compound recovery. Chloroform presented the highest capability to extract all target compounds with a horizontal shaker table (HST) for homogenization in the saponification step. For the pretreatment, a small amount of chloroform was used for 90 min at 50 °C and 6 min for the saponification time. The sample introduction in the GC injector was studied by evaluating pressure and injector temperature. High response for sterols and squalene were obtained between 19 and 23 psi and at 310 °C of injection temperature. The new method was able to determine different sterol concentrations: 0.2-0.6 mg kg-1 of squalene, 5-18 mg kg-1 of stigmasterol, 6 mg kg-1 of cholesterol, and 3 mg kg-1 of ß-sitosterol, showing high analytical performance and fulfilling all steps, thus proving to be a promising technique.

Addition of microencapsulated soybean molasses to pasta formulations / Efeito da adição de microcápsulas do melaço de soja em massas alimentícias

ABSTRACT: This study investigated the production of pasta with the addition of microencapsulated soybean molasses and its effect on the physicochemical, sensory, and microbiological characteristics and shelf life of the product. Three formulations were prepared, as follows: F1, control pasta; F2, pasta made with free extract; and F3, pasta made with soybean molasses microparticles, which were characterized in terms of their pH, water activity, color measurements, sensory evaluation, microbiological characterization, and shelf life via determination of the phenolic compounds remaining during a 28 day storage. The cooked pasta containing the microparticles retained 25% of the original phenolics up to 14th day of storage, meanwhile, the raw pasta presented 15% of the original phenolics up to the 21st day of storage. Good sensory acceptability was observed for all pasta containing the microparticles, with no differences from the control pasta; however, pasta made with free extract was less accepted when compared to the other types. The addition of microparticles did not change the microbiological profile, pH, water activity, or color of the pasta.

RESUMO: Este trabalho teve como objetivo desenvolver massas alimentícias adicionadas de microcápsulas de melaço de soja e avaliar o efeito das microcápsulas sobre as características físico-químicas, sensoriais, microbiológicas e vida de prateleira. As formulações das massas foram, controle (F1), com extrato livre (F2) e com microcápsulas (F3), foram realizadas as análises de pH, atividade de água, cor, análise sensorial, microbiológica e vida de prateleira dos fenólicos por 28 dias. As massas cozidas contendo microcápsulas permaneceram com 25% de fenólicos até o 14º dia, e as massas cruas com 15% de fenólicos até o 21° dia de armazenamento. As massas com microcápsulas mostraram boa aceitabilidade não diferindo da massa controle, entretanto as massas com o extrato livre mostraram menor aceitação em relação às demais. A adição das microcápsulas não alterou a parte microbiológica, pH, atividade de água e cor das massas.

Combining In-Tip Reaction and Infrared Thermal Imaging for Fast and Portable Enthalpimetric Analysis.

In this work, the in-tip thermal infrared enthalpimetry (in-tip TIE) method is proposed for fast enthalpimetric analysis. In this method, the reactions inside the tips of a multichannel pipette were combined with temperature monitoring by an infrared camera. The filter paper was used inside the tips to retain reagents as solutions (wetted paper mode) or as solids (dried paper mode) to perform neutralization, redox, or precipitation reactions. The dried reagents inside the tips were obtained by oven drying a solution retained in the filter paper. The determination of the total acidity of the vinegar, ascorbic acid in vitamin C tablets, and chloride in soy sauces and saline inhalation solutions was performed as examples of the application of the proposed method. The agreement with reference methods ranged from 98 to 107%. The use of reagents dried inside the tip was feasible, leading to a simple aspiration of sample solution within the 12 tips of the pipette to perform a rapid analysis (1 min). Therefore, up to 720 measurements in 1 h were feasible for in-tip TIE over up to 12 measurements for the reference methods. Moreover, miniaturization reduced reagent consumption and residue generation. For example, for in-tip TIE, only 3.6 mL of residues was generated (n = 12) over 60-240 mL in reference methods (n = 3). Contrarily to other TIE methods, no microplates or stirring was required, opening possibilities for field analysis since the multichannel pipette and the infrared camera are both operated with batteries.

Jabuticaba peel extract obtained by microwave hydrodiffusion and gravity extraction: A green strategy to improve the oxidative and sensory stability of beef burgers produced with healthier oils.

Hydrogelled emulsions (HE) from chia and linseed oils (1:1) were made with different concentrations (0, 6, 8, and 10%) of jabuticaba peel extract (JPE) obtained by microwave hydrodiffusion and gravity (MHG) extraction. Burgers (20% fat) were produced with the replacement of 60% of fat by HEs. The oxidative profile and the sensory quality of raw and cooked burgers were evaluated for 120 days (-18 °C). The JPE exhibited 1.72 mg/mL of phenolic compounds and 57,741.67 µmol TE/mL of antioxidant capacity. In addition, the MHG extraction eliminated the mesophilic bacteria from the jabuticaba peel. The burgers made with HE and without the addition of JPE showed a 5-fold increase in TBARS values when compared to the control. On the other hand, the addition of 10% JPE to HE was effective to maintain the lipid oxidation similar to the control until the 60th day of storage. Besides, the incorporation of JPE into HE reduced the sensory defects caused by the lipid reformulation.

Ultrasound assisted maceration for improving the aromatization of extra-virgin olive oil with rosemary and basil.

Aromatization of extra-virgin olive oil (EVOO) with aromatic plants is commonly used to enrich the oil with aromatic and antioxidant compounds. Ultrasound can be an alternative to accelerate this process. The objective of this work was to determine if ultrasound is able to accelerate EVOO aromatization with rosemary and basil and how it affects the migration of volatile and other compounds, the oxidative stability and the antioxidant capacity of the aromatized products. Ultrasound parameters (amplitude, time, and temperature of extraction) were optimized for each herb with central composite designs. Free fatty acid, peroxide value, K232, K270, ΔK, fatty acid profile, total phenolics, antioxidant capacity, polar compounds, oxidative stability and volatile compounds profile were evaluated in all samples. Physical effects of ultrasound on the herbs were observed by scanning electron microscopy. In the optimization, variables related to the oxidative processes were minimized and compounds migration and oxidative stability were maximized. Results were 70.09% amplitude, 36.6 min and 35 °C for rosemary and 95.98% amplitude, 9.9 min and 30 °C for basil. These conditions were compared to 7 and 15 days of conventional maceration (CM). Aromatization of EVOO with rosemary, both by ultrasound assisted maceration (UAM) or CM, improved total phenolics, terpenes, esters, ketones, stability and induction times, as well as decreased the values for the quality parameters. The use of UAM accelerated the process to 37 min. However, aromatization with basil by CM increased the values for the quality parameters and reduced the total phenolics, the antioxidant capacity and the induction and stability times. UAM with basil reached better results than those observed for CM, in only 10 min. In conclusion, rosemary is more appropriate than basil for EVOO aromatization, and UAM was the best choice to accelerate the processes when compared to CM.

Microwave-Induced Combustion in Disposable Vessels: A Novel Perspective for Sample Digestion.

A novel system for sample digestion was proposed based on microwave-induced combustion in disposable vessels (MIC-DV) for trace elements determination by inductively coupled plasma optical emission spectrometry (ICP-OES). As a proof of concept, botanical samples were digested by MIC-DV for further determination of Al, Cr, Cu, Fe, Mn, Sr, and Zn. The system consists of a quartz holder (a modified version of conventional MIC) placed inside disposable polypropylene (PP) vessels. The quartz holder was carefully designed to avoid excessive heating and damaging of the vessel walls. For the combustion, the PP vessels containing the quartz holder and sample were placed in a specially designed metallic rotor that prevents the heating of absorbing solution and allows the use of a domestic microwave oven for sample ignition. After combustion, the digestion vessel was shaken to ensure the analytes' absorption. The single-vessel principle was fulfilled, since no further dilution or liquid transfer was required and the same PP vessel used for digestion allowed solution storage until element determination. The influences of absorbing solution (diluted HNO3 and water) and sample mass (10 to 30 mg) were evaluated. By using the proposed MIC-DV system, low volumes of diluted absorbing solutions (5 mL of 1 mol L-1 HNO3) were possible, allowing the use of low reagent amounts and low energy consumption, since microwave irradiation is used only for sample ignition. The agreement with certified values ranged from 92 to 108% for all analytes, whereas the precision was below 15%. All of these advantages, combined with the use of low-cost disposable vessels and instrumentation, make MIC-DV suitable to be used for research and routine analysis.

Effect of ultrasound on proteolysis and the formation of volatile compounds in dry fermented sausages.

Ultrasound (US) is an emerging technology capable of affecting enzymes and microorganisms, leading to the release of amino acids and the formation of volatile compounds. The effect of different exposure times (0, 3, 6, and 9 min) of US (25 kHz, 128 W) on the proteolysis and volatile compounds of dry fermented sausages during processing (day 0 and 28) and storage (day 1 and 120) was investigated. Lower alanine, glycine, valine, leucine, proline, methionine, and tyrosine levels were observed at the beginning of manufacture for the sample subjected to 9 min of US (p < 0.05) when compared to the control. During the storage period, the samples subjected to US exposure for 3 and 6 min exhibited higher free amino acid levels. A greater formation of hexanal, pentanal, and hexanol was observed in the US-treated samples when compared to the control (p < 0.05), as well as other derivatives from the oxidation reactions during the storage. The use of US (25 kHz and 128 W) in the manufacture of dry fermented sausages can affect the proteolysis and the formation of compounds derived from lipid oxidation during the storage.

Rapid, Noninvasive, and Nondestructive Method for Biofilm Imaging on Metallic Surfaces Using Active Thermography.

A simple, rapid, low-cost method was proposed for the imaging of Pseudomonas aeruginosa biofilms on metallic surfaces using an infrared camera. Stainless steel coupons were cooled to generate a thermal gradient in relation to biofilm for active thermography (AT). Both cooling and image acquisition times were optimized and the images obtained with AT were compared with those from scanning electron microscopy. A free software (Thermofilm) was developed for image processing and the results were compared with the software ImageJ, with good agreement (from 87.7 to 103.8%). Images of coupons treated with sanitizer (peracetic acid) were obtained to show the applicability of the proposed method for biofilm studies. All analytical steps could be performed in 3 min in a noncontact, nondestructive, low-cost, portable, and easy-to-use way.

Is it possible to reduce the cooking time of mortadellas using ultrasound without affecting their oxidative and microbiological quality?

This study evaluated the reduction of cooking time of mortadellas using ultrasound (US, 25 kHz) and the effects on the oxidative and microbiological quality of the product. Three cooking conditions were studied: control, cooking time traditionally adopted by the meat industry; TUS and TWUS: cooking with and without US application and 50% reduction of the traditional cooking time, respectively. The application of US did not increase the peroxide, conjugated dienes, and TBARS indices and did not accelerate the protein oxidation. In addition, no significant changes were observed in the color of the mortadellas subjected to ultrasonic-assisted cooking. TUS and control presented a similar mesophilic, psychrotrophic and lactic acid bacteria counts during storage. The ultrasonic-assisted cooking provided a faster increase and higher homogeneity in the internal temperature of the mortadellas. Therefore, the US can be considered a promising technology to improve the cooking process of mortadellas.

Infrared enthalpymetric methods: A new, fast and simple alternative for sodium determination in food sauces.

This work developed a new technique and an application of an existing approach to determine sodium in food sauces, involving enthalpimetric reactions in the infrared. Infrared Thermometric Titration (TT-IR) was utilized, with simple analyzers and low-cost measurement instruments for the acquisition of the surface temperature generated in the sodium precipitation reaction and development of software for the acquisition and processing of data using Raspberry Pi. The sodium was also quantified by Thermal Infrared Enthalpimetry (TIE), a recently developed technique. The rapid and simple quantification of sodium by the TT-IR and TIE showed the possibility of a selective reaction for sodium, using aluminum nitrate, potassium and ammonium fluoride in an acid medium, with reduction of the reagents and without the digestion step in the sample preparation. The results acquired through TT-IR and TIE corroborated the Flame Atomic Emission Spectrometry (FAES) with 96 to 103% and 95 to 102%, respectively.