Comparison of hyperspectral imaging and spectrometers for prediction of cheeses composition.

Artisanal cheeses are part of the heritage and identity of different countries or regions. In this work, we investigated the spectral variability of a wide range of traditional Brazilian cheeses and compared the performance of different spectrometers to discriminate cheese types and predict compositional parameters. Spectra in the visible (vis) and near infrared (NIR) region were collected, using imaging (vis/NIR-HSI and NIR-HSI) and conventional (NIRS) spectrometers, and it was determined the chemical composition of seven types of cheeses produced in Brazil. Principal component analysis (PCA) showed that spectral variability in the vis/NIR spectrum is related to differences in color (yellowness index) and fat content, while in NIR there is a greater influence of productive steps and fat content. Partial least squares discriminant analysis (PLSDA) models based on spectral information showed greater accuracy than the model based on chemical composition to discriminate types of traditional Brazilian cheeses. Partial least squares (PLS) regression models based on vis/NIR-HSI, NIRS, NIR-HSI data and HSI spectroscopic data fusion (vis/NIR + NIR) demonstrated excellent performance to predict moisture content (RPD > 2.5), good ability to predict fat content (2.0 < RPD < 2.5) and can be used to discriminate between high and low protein values (∼1.5 < RPD < 2.0). The results obtained for imaging and conventional equipment are comparable and sufficiently accurate, so that both can be adapted to predict the chemical composition of the Brazilian traditional cheeses used in this study according to the needs of the industry.

Thiamine, cysteine and xylose added to the Maillard reaction of goat protein hydrolysate potentiates the formation of meat flavoring compounds.

A protein hydrolysate of goat viscera added with xylose, cysteine, and thiamine under different pH was used to prepare a meat flavoring. Goat viscera hydrolysate and flavoring were subjected to analysis of physicochemical characteristics, amino acid profile, sugars, fatty acids, and volatile profile. Meat aroma characteristics were initiated in the hydrolysate, in which Strecker's pyrazines and aldehydes were identified, which also had fatty acids and amino acids available for the formation of 96 volatile compounds in the flavorings via lipid manipulation, Maillard occurrence, Strecker manipulation and interactions among these means. Maillard reaction products with intense meat aroma, such as 2-methyl-3-furanthiol, 2-furfurylthiol and, bis(2-methyl-3-furyl) disulfide were isolated only in the flavoring at pH 4. In contrast, the flavoring at pH 6 showed a higher concentration than all the other compounds, providing a lower meat characteristic, but an intense sweet, fatty and goat aroma.

Influence of the freezing level on atmospheric rivers in High Mountain Asia: WRF case studies of orographic precipitation extremes.

Atmospheric rivers (ARs) reach High Mountain Asia (HMA) about 10 days per month during the winter and spring, resulting in about 20 mm day-1 of precipitation. However, a few events may exceed 100 mm day-1, providing most of the total winter precipitation and increasing the risk of precipitation-triggered landslides and flooding, particularly when the height of the height of the 0 ∘C isotherm, or freezing level is above-average. This study shows that from 1979 to 2015, integrated water vapor transport (IVT) during ARs that reach Western HMA has increased 16% while the freezing level has increased up to 35 m. HMA ARs that have an above-average freezing level result in 10-40% less frozen precipitation compared to ARs with a below-average freezing level. To evaluate the importance of these trends in the characteristics of ARs, we investigate mesoscale processes leading to orographic precipitation using Advanced Weather Research and Forecasting (ARW-WRF) simulations at 6.7 km spatial resolution. We contrast two above- and below- average freezing level AR events with otherwise broadly similar characteristics and show that with a 50-600 m increase in freezing level, the above-average AR resulted in 10-70% less frozen precipitation than the below-average event. This study contributes to a better understanding of climate change-related impacts within HMA's hydrological cycle and the associated hazards to vulnerable communities living in the region.

Unveiling the bioactivity and bioaccessibility of phenolic compounds from organic coffee husks using an in vitro digestion model.

BACKGROUND: The large quantities of by-products generated in the coffee industry are a problem. Studies related to the biological potential of organic coffee husks are still limited. The aim of this work was to investigate the occurrence of phenolic compounds in organic coffee husks and to evaluate their potential as a source of bioactive dietary components. RESULTS: To achieve this objective, three extracts were prepared, namely extractable polyphenols (EPs), hydrolyzable non-extractable polyphenols (H-NEPs), and non-extractable polyphenols (NEPs). These extracts were characterized and evaluated for their bioactive properties after simulated gastrointestinal digestion. The results show that the extraction process affected the occurrence of phenols from coffee peels, especially for caffeic acid, gallic acid, and chlorogenic acid. The free and bound polyphenols found in the extracts and digests not only showed antioxidant properties against 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals but were also strongly bioavailable and had good anticoagulant potential. CONCLUSION: These results highlight the potential health benefits of phytochemicals from coffee husks and open new perspectives for the use of such compounds in dietary supplements. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Oxidative stability of white striping chicken breasts: effect of cold storage and heat treatments.

This study aimed to investigate the level of lipid and protein oxidation in poultry breasts with severe white striping (WS; striation thickness > 1 mm) and nonaffected meats (N; normal breast) during storage under refrigeration (1°C for 14 d) and freezing (-18°C for 90 d). WS presented higher lipid content, although no difference in protein content was detected, compared to normal broiler breast (N). Regarding oxidative damages, a reduction in malondialdehyde and carbonyl protein, hexanal, octanal and nonanal levels, alongside the interaction of these compounds with other compounds in raw, roasted, and reheated breasts was observed under refrigerated storage (14 d). Freezing storage promotes an increase in carbonyls proteins, hexanal, octanal and nonanal levels at 45 d of storage in poultry meats and subsequent decrease, indicating the evolution of oxidative reactions. Regardless of the type of storage, in general, breasts with WS myopathy have higher levels of lipid and protein oxidation.

Deciphering the underlying mechanisms of the oxidative perturbations and impaired meat quality in Wooden breast myopathy by label-free quantitative MS-based proteomics.

The study aimed to investigate biochemical mechanisms occurred in Wooden breast (WB) chicken meat, with attention to the impact on meat quality. Commercial chicken breasts were classified as Normal (N, n = 12), WB-M (moderate degree; focal hardness on cranial region, n = 12) and WB-S (severe degree; extreme and diffused hardness over the entire surface, n = 12). Samples were analyzed for physico-chemical properties, oxidative damage to lipids and proteins, and discriminating sarcoplasmic proteins by using a Q-Exactive mass spectrometer. WB meat presented impaired composition and functionality and higher levels of lipid and protein oxidation markers than N meat. The proteomic profile of WB-S presents a dynamic regulation of the relevant proteins involved in redox homeostasis, carbohydrate, protein and lipid metabolisms. Proteomics results demonstrate that the physiological and metabolic processes of muscles affected by WB myopathy are involved in combating the inflammatory process and in repairing the damaged tissue by oxidative stress.

Quality of Brazilian stingless bee honeys: Cephalotrigona capitata/mombucão and Melipona scutellaris Latrelle/uruçu.

Honeys produced by stingless bees Cephalotrigona capitata and Scutellaris Latrelle in the Caatinga and Atlantic Forest biomes were characterized in terms of chemical composition, antioxidant activity and phenolic, volatile and sensory profile. 'Mombucão' honey showed higher water activity, acidity, % sucrose and % organic acids, while 'uruçu' honey showed the highest % fructose and glucose. Nineteen phenolic compounds and flavonoids were quantified, with emphasis on epicatechin gallate, myricetin, quercetin and procyanidin A2. 'Mombucão' honey stood out with the highest to antioxidant activity. A total of 133 volatile compounds were identified in honeys, with emphasis on terpenes (41) and esters (26). 'Mombucão' honey presented a differentiated sensory profile and was characterized by the prevalence of acid and citrus aroma and flavor, while 'uruçu' honey presented a more characteristic sweet and woody aroma and flavor. The variability in the composition of honeys probably resulted from bee species, floral species and geographic origins.

Juá (Ziziphus joazeiro Mart.) mucilage and juá by-product phenolic extract improve quality parameters and retain bioactive compounds in fresh-cut pineapple during storage.

This study evaluated the effects of coatings with juá mucilage (JM), juá mucilage incorporated with phenolic extract from juá (JMPE), and juá mucilage with gum arabic (JM-GA) on quality parameters, bioactive compounds and antioxidant activity of fresh-cut pineapple during 9 days at 5 ± 1 °C. JM and JMPE coatings were effective in reducing enzymatic activity, consequently reducing changes in fruit color compared to uncoated fresh-cut pineapple (C). JM coating was more efficient in reducing metabolic activity with the lowest conversion of sugars into glucose, fructose and organic acids. In addition, JMPE coating showed the highest retention of phenolics. On the other hand, JM had a minor reduction in antioxidant activity in FRAP (39.55 %) and ORAC (33.46 %) assay compared to other coatings (p ≤ 0.05). Findings indicate that JM and JMPE are promising for application to preserve the overall quality and to extend the shelf life of fresh-cut pineapple.

Functional and morphologic dysfunctions in the airways of rats submitted to an experimental model of obesity-exacerbated asthma.

The obesity-exacerbated asthma phenotype is characterized by more severe asthma symptoms and glucocorticoid resistance. The aim of this study was to standardize an obesity-exacerbated asthma model by a high glycemic level index (HGLI) diet and ovalbumin (OVA) sensitization and challenges in Wistar rats. Animals were divided into groups: control (Ctrl), obese (Ob), asthmatic (Asth), obese asthmatic (Ob + Asth) and obese asthmatic treated with dexamethasone (Ob + Asth + Dexa), and in vivo and in vitro functional and morphological parameters were measured. After HGLI consumption, there was an increase in body weight, fasting blood glucose, abdominal circumferences, body mass index and adiposity index. Respiratory function showed a reduction in pulmonary tidal volume and ventilation. In isolated tracheas, carbachol showed an increase in contractile efficacy in the Ob, Ob + Asth and Ob + Asth + Dexa, but mostly on Ob + Asth. Histological analysis of lungs showed peribronchovascular inflammation and smooth muscle hypertrophy and extracellular remodeling on Ob + Asth and Ob + Asth + Dexa. An obesity-exacerbated asthma model was successfully established. Therefore, this model allows further molecular investigations and the search for new therapies for the treatment and relief of symptoms of patients with obesity-induced resistant asthma.

Oxidative stability of chicken burgers using organic coffee husk extract.

The antioxidant capacity of organic coffee husk extract (Coffee arabica L.) added to chicken burgers was evaluated. Two formulations were prepared: with addition of the extract (100 and 200 ppm CAE/kg), in addition to control formulations without the addition of antioxidant, and with the addition of synthetic antioxidant. The products were characterized by physical and chemical analysis and analyzed for oxidative stability during 45 days of storage under freezing. The addition of extract in the proportion of 200 ppm CAE/kg of hamburger revealed efficacy against lipid oxidation equivalent to treatment with a synthetic antioxidant. As for protein oxidation, there was no pro or antioxidant influence in the treatments. The addition of organic coffee husk extract to chicken hamburgers is thus indicated, being considered as a potential natural additive. In addition, the use of coffee husks helps to minimize the lager amounts of agro-industrial by-products generated by the coffee industry.

Winter and spring atmospheric rivers in High Mountain Asia: climatology, dynamics, and variability.

Atmospheric rivers (ARs) that reach the complex terrain of High Mountain Asia (HMA) cause significant hydrological impacts for millions of people. While ARs are often associated with precipitation extremes and can cause floods and debris flows affecting populated communities, little is known about ARs that reach as far inland as HMA. This paper characterizes AR types and investigates dynamical mechanisms associated with the development of ARs that typically affect HMA. Combined empirical orthogonal function (cEOF) analysis using integrated water vapor transport (IVT) is applied to days where an AR reaches HMA. K-means cluster analysis applied to the first two principal components uncovered three subtypes of AR events with distinct synoptic characteristics during winter and spring months. The first subtype increases precipitation and IVT in Western HMA and is associated with a zonally oriented wave train propagating within the westerly jet waveguide. The second subtype is associated with enhanced southwesterly IVT, anomalous upper-level cyclonic circulation centered on 45 ∘ E, and precipitation in Northwestern HMA. The third subtype shows anomalous precipitation in Eastern HMA and southwesterly IVT across the Bay of Bengal. Interannual variations in the frequency of HMA ARs and relationships with various teleconnection patterns show that western HMA AR subtypes are sensitive to well-known remote large-scale climate factors, such as the El Niño Southern Oscillation, Arctic Oscillation, and the Siberian High. These results provide synoptic characterization of the three types of ARs that reach HMA and reveal the previously unexplored significance of their contribution to winter and spring precipitation. Supplementary Information: The online version contains supplementary material available at 10.1007/s00382-021-06008-z.

Improving the poor texture and technological properties of chicken wooden breast by enzymatic hydrolysis and low-frequency ultrasound.

Wooden breast (WB) is a recurrent myopathy in fast-growing birds, which alters the appearance, functionality, and the texture of the breast muscle. The objectives of this study were (i) to evaluate the effect of a combined use of papain enzyme and ultrasound on the texture of WB chicken using response surface methodology and (ii) to assess the effect of marinating on the quality of WB chicken meat. Full factorial experimental design method was used to obtain the ideal conditions to soften the WB meat. The independent variables were the concentration of papain (0.1%-0.3%) and the time in ultrasonic bath (10-30 min); shear force (SF) was the dependent variable. The optimum results were obtained at a concentration of 0.2% papain and 20 min on ultrasound. Papain enzyme had a great influence on the texture of WB meat, reducing its hardness. However, the effect of the ultrasound time on the SF response was not observed. The marinated WB meat showed similar SF values and texture profile than those from normal (N) meat, with reduction in the parameters of protein and lipid oxidation. The use of papain without ultrasound bath proved to be an efficient means for improving the tenderness of WB breasts. PRACTICAL APPLICATION: This study shows the efficiency of the application of two technological procedures (enzymatic treatment and ultrasound) to improve the texture profile and technological properties of chicken breasts affected by the wooden breast myopathy. The economic loss caused by the world-wide occurrence of wooden breast is enormous, and the application of papain has been found to counteract the impaired properties of this abnormal chicken breasts. Since papain is already widely used in the food industry to tenderize meat, its application in improving the quality of WB meat is straightforward.

Reimagine fire science for the anthropocene.

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical changes to ecosystems, fire danger is increasing, and fires are having increasingly devastating impacts on human health, infrastructure, and ecosystem services. Increasing fire danger is a vexing problem that requires deep transdisciplinary, trans-sector, and inclusive partnerships to address. Here, we outline barriers and opportunities in the next generation of fire science and provide guidance for investment in future research. We synthesize insights needed to better address the long-standing challenges of innovation across disciplines to (i) promote coordinated research efforts; (ii) embrace different ways of knowing and knowledge generation; (iii) promote exploration of fundamental science; (iv) capitalize on the "firehose" of data for societal benefit; and (v) integrate human and natural systems into models across multiple scales. Fire science is thus at a critical transitional moment. We need to shift from observation and modeled representations of varying components of climate, people, vegetation, and fire to more integrative and predictive approaches that support pathways toward mitigating and adapting to our increasingly flammable world, including the utilization of fire for human safety and benefit. Only through overcoming institutional silos and accessing knowledge across diverse communities can we effectively undertake research that improves outcomes in our more fiery future.

The mitochondrial-targeted reactive species scavenger JP4-039 prevents sulfite-induced alterations in antioxidant defenses, energy transfer, and cell death signaling in striatum of rats.

Sulfite oxidase (SO) deficiency is a disorder caused either by isolated deficiency of SO or by defects in the synthesis of its molybdenum cofactor. It is characterized biochemically by tissue sulfite accumulation. Patients present with seizures, progressive neurological damage, and basal ganglia abnormalities, the pathogenesis of which is not fully established. Treatment is supportive and largely ineffective. To address the pathophysiology of sulfite toxicity, we examined the effects of intrastriatal administration of sulfite in rats on antioxidant defenses, energy transfer, and mitogen-activated protein kinases (MAPK) and apoptosis pathways in rat striatum. Sulfite administration decreased glutathione (GSH) concentration and glutathione peroxidase, glucose-6-phosphate dehydrogenase, glutathione S-transferase, and glutathione reductase activities in striatal tissue. Creatine kinase (CK) activity, a crucial enzyme for cell energy transfer, was also decreased by sulfite. Superoxide dismutase-1 (SOD1) and catalase (CAT) proteins were increased, while heme oxygenase-1 (HO-1) was decreased. Additionally, sulfite altered phosphorylation of MAPK by decreasing of p38 and increasing of ERK. Sulfite further augmented the content of GSK-3ß, Bok, and cleaved caspase-3, indicating increased apoptosis. JP4-039 is a mitochondrial-targeted antioxidant that reaches higher intramitochondrial levels than other traditional antioxidants. Intraperitoneal injection of JP4-039 before sulfite administration preserved activity of antioxidant enzymes and CK. It also prevented or attenuated alterations in SOD1, CAT, and HO-1 protein content, as well as changes in p38, ERK, and apoptosis markers. In sum, oxidative stress and apoptosis induced by sulfite injection are prevented by JP4-039, identifying this molecule as a promising candidate for pharmacological treatment of SO-deficient patients.

Pinpointing oxidative stress behind the white striping myopathy: depletion of antioxidant defenses, accretion of oxidized proteins and impaired proteostasis.

BACKGROUND: This study aimed to investigate the molecular mechanisms involved in the onset of the white striping (WS) myopathy with particular attention to the role of oxidative stress and protein oxidation in the loss of meat quality. RESULTS: It was found that WS-M (moderate degree; white stripes <1 mm thickness) and WS-S (severe degree; white stripes >1 mm thickness) breast presented higher pH, hardness, redness, lipid, and collagen content, and lower lightness than normal breast. Compared with the latter, WS-S had a more severe loss of protein thiols (70.7% less thiols than in N), reduced activity of antioxidant enzymes such as catalase (23 versus 40 U g-1 ), glutathione peroxidase (0.21 versus 0.54 U g-1 ), and superoxide dismutase (56 versus 73 U g-1 ), and consequently, had greater accretion of thiobarbituric acid reactive substances (0.64 versus 0.22 mg MDAkg-1 muscle), allysine (3.1 versus 1.9 nmol mg-1 protein) and Schiff base structures (645 versus 258 fluorescent units). The analysis of sarcoplasmic proteins revealed that muscles severely affected by the myopathy suffered a chronic impairment of physiological (upregulation of sarcoplasmic reticulum Ca2+ ATPase, sarcalumenin and calsequestrin-2) and metabolic processes (downregulation of pyruvate kinase, creatine kinase, and l-lactate dehydrogenase). CONCLUSION: The overexpression of ribonuclease / angiogenin inhibitor 1 and Kelch-like proteins in WS chicken breasts indicates altered protein turnover plausibly mediated by oxidative stress and accumulation of oxidized proteins. © 2020 Society of Chemical Industry.

Occurrence of wooden breast and white striping in Brazilian slaughtering plants and use of near-infrared spectroscopy and multivariate analysis to identify affected chicken breasts.

White Striping (WS) and Wooden Breast (WB) are emerging poultry myopathies that occur worldwide, affecting the quality of meat. The aim of this study was to evaluate the occurrence of N, WS, WB, and WS/WB (myopathies combined) in chicken breast from Brazilian commercial plant, comparing (1) inspection based on visual aspect and palpation of Pectoralis major muscle, and (2) identification of these myopathies by near-infrared Spectroscopy (NIRS). Chickens slaughtered at Brazilian commercial plant at four age ranges (4 to 5, 6 to 7, 8 to 9, and 65 weeks) were inspected. Spectral information was acquired using a portable NIR spectrometer, and classification models were performed using and Successive Projection Algorithm-Linear Discriminant Analysis (SPA-LDA) and Soft Independent Modeling of Class Analogy (SIMCA) to distinguish normal and affected muscles. Results showed that occurrence of myopathies was aggravated by age of slaughter, as chicken slaughtered at 4 to 5 and 65 weeks exhibited 13.6 and 95% of myopathies, respectively. Birds slaughtered at 65 weeks showed no occurrence of WB, isolated or combined with WS. It was not possible to differentiate the WB and WS/WB classes; therefore, those samples were grouped (WB+WS/WB). SPA-LDA model showed greater accuracy (92 to 93%) in identifying Normal (N), WS, and WB+WS/WB groups, compared to SIMCA (89 to 91%). It can be concluded that the level of occurrence of myopathies in meat is directly related to the age of slaughter. This study demonstrated that NIRS combined with SPA-LDA model could be used as a tool to detect myopathies in chicken breast. This technique has potential for application in industrial processing lines as an alternative to the traditional methods of identification. PRACTICAL APPLICATION: This study shows that NIRS combined with chemometric techniques can be used to identify chicken breast myopathies in a wide range of ages at slaughter. In addition to being able to discriminate chicken muscles into subclasses, namely, Normal, WS, and WB/WB+WS, this technique has potential for application in industrial processing lines as it is a portable and nondestructive method. This procedure is emphasized as an alternative to the conventional method of identification based on palpation and visual assessment of muscle.

Impact of chicken wooden breast on quality and oxidative stability of raw and cooked sausages subjected to frozen storage.

BACKGROUND: Considering (i) the increased incidence of wooden breast (WB) myopathy in broilers, (ii) the poor meat quality in such breasts and (iii) the lack of studies on the industrial use of WBs; the objective of this study was to investigate the quality of chicken sausages made with WB under frozen conditions. Three formulations of chicken sausage [100% normal (N) breast, 100% WB, and 50% N breast + 50% WB] were considered and raw and cooked (70 °C/10 min) sausages were frozen for 180 days and evaluated for their quality and oxidative stability. RESULTS: WB formulations exhibited higher pH, moisture (%), and shear force (SF), associated with lower water holding capacity (WHC) and fat (%). During the freezing period, there was a decrease in WHC and redness (a*) and an increase in cooking loss (CL) and SF for all formulations. Additionally, during freezing, thiobarbituric acid-reactive substances values were higher in raw sausages made with N breast than in sausage made with WB probably due to the higher fat content in the former. Results showed that the products did not reach noticeable rancid levels (<2 mg malondialdehyde/kg) and that WB sausage presented great resistance to oxidation, which suggests that WB sausage can be kept frozen at -20 °C for up to 198 days. CONCLUSION: Using WBs for the manufacture of chicken sausages subjected to freezing is a viable option given their overall quality and resistance to oxidation. © 2020 Society of Chemical Industry.

Causality of Biodiversity Loss: Climate, Vegetation, and Urbanization in China and America.

Essential for directing conservation resources is to identify threatened vertebrate regions and diagnose the underlying causalities. Through relating vertebrates and threatened vertebrates to the rainfall-runoff chain, to the food chain, and to the human impact of urbanization, the following relationships are noticed: (i) The Earth's vertebrates generally show increasing abundance and decreasing threatened species indicator (threatened species number/species abundance) for a higher Normalized Difference Vegetation Index (NDVI) or larger city-size. (ii) Regional vertebrates reveal a notable 'U-shape profile' ('step-like jump') of threatened species indicator occurs in the moderate (high) NDVI regions in China (America). (iii) Positive/green city states emerge in China and are characterized by the lowest threatened species indicators in areas of low to moderate greenness, where the greenness trend of change during the last 30 years is about three times higher in the urbanized areas than over land. (iv) Negative/brown city states emerge in America revealing high threatened species indicators for greenness exceeding NDVI > 0.2, where similar greenness trends are of both urbanized and land areas. The occurrence of green and brown city states suggests a biodiversity change pattern characterized by the threatened species indicator declining from city regimes with high to those with low indicator values for increasing ratio of the city-over-land NDVI trends.

Malondialdehyde interferes with the formation and detection of primary carbonyls in oxidized proteins.

Carbonylation is one of the most remarkable expressions of the oxidative damage to proteins and the DNPH method the most common procedure to assess protein oxidation in biological samples. The present study was elicited by two hypotheses: i) is malondialdehyde, as a reactive dicarbonyl, able to induce the formation of allysine through a Maillard-type reaction? and ii) to which extent does the attachment of MDA to proteins interfere in the assessment of protein carbonyls using the DNPH method? Human serum albumin (HSA), human hemoglobin (HEM) and ß-lactoglobulin (LAC) (5 mg/mL) were incubated with MDA (0.25 mM) for 24 h at 37 °C (HSA and HEM) or 80 °C (LAC). Results showed that MDA was unable to induce oxidative deamination of lysine residues and instead, formed stable and fluorescent adducts with proteins. Such adducts were tagged by the DNPH method, accounting for most of the protein hydrazones quantified. This interfering effect was observed in a wide range of MDA concentrations (0.05-1 mM). Being aware of its limitations, protein scientists should accurately interpret results from the DNPH method, and apply, when required, other methodologies such as chromatographic methods to detect specific primary oxidation products such as allysine.

The impaired quality of chicken affected by the wooden breast myopathy is counteracted in emulsion-type sausages.

The aim of this study was to evaluate the suitability of using chicken meat affected by wooden breast (WB) myopathy in the production of chicken sausages. Compare the technological and sensory properties of such sausages were compared with those produced from normal (N) breast meat. Three types of chicken sausages were elaborated: 100% containing N chicken meat, 100% of WB chicken meat and 50% N/50% of WB meat. The WB chicken meat presented higher values for pH, L*, moisture, cooking loss, shear force, hardness, chewiness, adhesiveness and gumminess; while WHC and protein content were higher for N chicken meat. N and WB chicken sausages presented similar values of WHC, a*, b* color values, protein content and TBARS. QDA indicated no sensory differences between the three sausage formulations, so did the acceptability and purchase intention. Therefore, WB chicken meat may be used to produce chicken sausages combined or not with N chicken meat. Further studies, however, may be required to investigate the nutritional value and digestibility of WB meat and derived products.