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The objective of this study was to distinguish between the Tunisian Djebel lamb meat and meat from typical Tunisian production systems (PSs) through the fatty acids (FAs) profile and the stable isotope ratio analysis (SIRA). Thirty-five lambs from three different regions and PSs (D = Djebel, B = Bou-Rebiaa, and O = Ouesslatia) were considered for this purpose. The results demonstrated that the PS and the geographic origin strongly influenced the FA profile of lamb meat. It was possible to discriminate between the Djebel lamb meat and the rest of the dataset thanks to the quantification of the conjugated linoleic acids (CLA) and the branched chain FAs. Moreover, statistically different concentrations of saturated, monounsaturated and polyunsaturated FAs and a different n-6/n-3 ratio were found for grazing (D and BR) and indoor (O) lambs, making it possible to discriminate between them. As for the stable isotope ratio analysis, all parameters made it possible to distinguish among the three groups, primarily on the basis of the dietary regimen (δ(13C) and δ(15N)) and breeding area (δ(18O) and δ(2H)).
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Ácidos Graxos , Carne Vermelha , Ovinos , Animais , Ácidos Graxos/análise , Tunísia , Carne Vermelha/análise , Dieta/veterinária , Carne/análise , Isótopos/análise , Ração Animal/análiseRESUMO
Fatty acids (FAs) metabolism in animals represents an important field of study since they influence the quality and the properties of the meat. The aim of this study is to assess the possibility to discriminate the diets of cows in different animal compartments and to study the fate of dietary FAs in the bovine organism, using carbon isotopic ratios. Five FAs, both essential (linoleic and linolenic) and non-essential (palmitic, stearic, and oleic) in four compartments (feed, rumen, liver, meat) of animals fed two different diets (based on either C3 or C4 plants) were considered. For all compartments, the carbon isotopic ratio (δ13C) of all FAs (with few exceptions) resulted significantly lower in cows fed on C3 than C4 plants, figuring as a powerful tool to discriminate between different diets. Moreover, chemical reactions taking place in each animal compartment result in fraction processes affecting the δ13C values. The δ13CFAs tendentially increase from feed to meat in group C3. On the other hand, the δ13CFAs generally increase from rumen to liver in group C4, while δ13CFAs of rumen and meat are mostly not statistically different. Different trends in the δ13CFAs of the two groups suggested different FAs fates depending on the diet.
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Dieta , Rúmen , Ração Animal/análise , Animais , Isótopos de Carbono/metabolismo , Bovinos , Dieta/veterinária , Ácidos Graxos/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Rúmen/metabolismoRESUMO
The purpose of this study was to address the lack of knowledge regarding the stable isotopic composition of beef from zebu cattle reared in tropical Africa. Sixty beef carcasses belonging to the most common zebu breeds (Goudali, white Fulani, and red Mbororo) were selected and classified according to their subcutaneous fat color (white, cream or yellow). The stable isotope ratios of five bioelements-H, O, C, N, and S-in muscle fractions and the fatty acids composition were analyzed. Zebu meat from Cameroon shows peculiar δ13C values, related to the almost exclusive intake of grazed tropical grasses with photosynthetic cycle C4. It also shows δ2H and δ18O values higher than those reported in other areas of the world and correlated with the isotopic composition of animal drinking water. The white subcutaneous fat ("white type") zebu showed higher δ2H and lower δ13C than the "yellow type", that is correlated with a higher content of polyunsaturated fatty acid (PUFA) and a lower amount of saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA). Multielement analysis seems to provide promising results for tracing the regional origin of Cameroon beef and some aspects of the livestock system, such as the nutritional status of the animals.
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Ácidos Graxos/análise , Isótopos/análise , Carne Vermelha/análise , Animais , Camarões , Bovinos , Geografia , Marcação por IsótopoRESUMO
The microbiota of different types of Italian high-moisture Mozzarella cheese produced using cow or buffalo milk, acidified with natural or selected cultures, and sampled at the dairy or at the mass market, was evaluated using a Next Generation Sequencing approach, in order to identify possible drivers of the bacterial diversity. Cow Mozzarella and buffalo Mozzarella acidified with commercial cultures were dominated by Streptococcus thermophilus, while buffalo samples acidified with natural whey cultures showed similar prevalence of L. delbrueckii subsp. bulgaricus, L. helveticus and S. thermophilus. Moreover, several species of non-starter lactic acid bacteria were frequently detected. The diversity in cow Mozzarella microbiota was much higher than that of water buffalo samples. Cluster analysis clearly separated cow's cheeses from buffalo's ones, the former having a higher prevalence of psychrophilic taxa, and the latter of Lactobacillus and Streptococcus. A higher prevalence of psychrophilic species and potential spoilers was observed in samples collected at the mass retail, suggesting that longer exposures to cooling temperatures and longer production-to-consumption times could significantly affect microbiota diversity. Our results could help in detecting some kind of thermal abuse during the production or storage of mozzarella cheese.
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Bactérias/isolamento & purificação , Queijo/microbiologia , Microbiologia de Alimentos , Microbiota/genética , Animais , Bactérias/classificação , Bactérias/genética , Biodiversidade , Búfalos , Bovinos , Queijo/análise , Análise por Conglomerados , DNA Bacteriano/genética , Metagenômica , Leite/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
BACKGROUND: One of the main constraints established by organic legislation that limits the development of the rearing of young bulls is the ban on the use of genetically modified organisms (GMO). Most of the worldwide cultivated soybean is GMO, therefore the use of alternative protein sources should be evaluated. In this study, the effect of dietary substitution of soybean with pea (Pisum sativum L.) on carcass characteristics and meat quality of dual purpose young bulls reared following the organic method was investigated. RESULTS: Twenty-four young bulls of Rendena breed were randomly assigned to two diet treatments differing in protein supplement (soybean (SB) or field pea (FP)). Carcass characteristics and meat chemical composition, colour, cooking loss and Warner-Bratzler shear force did not differ between groups. Regarding meat fatty acid composition, SB showed higher concentrations of C18:0 and C18:1 t and lower C16:1n-9c, C14:0, C17:1n-9c and C18:1n-9c than FP. In descriptive sensory analysis, trained judges were not able to differentiate meats from SB and FP, which also had similar overall liking expressed by consumers. CONCLUSION: The results of this study indicate that FP can replace SB in the diet of dual purpose young bulls with only a minor influence on fatty acid composition and no effect on carcass characteristics and meat quality. © 2017 Society of Chemical Industry.
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Ração Animal/análise , Bovinos/metabolismo , Suplementos Nutricionais/análise , Glycine max/metabolismo , Carne/análise , Pisum sativum/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cruzamento , Bovinos/crescimento & desenvolvimento , MasculinoRESUMO
BACKGROUND: This study investigated the sensory properties and acceptability of different Protected Designation of Origin (PDO) dry-cured hams. For each PDO, two genotypes were selected: IL×LW (reference hybrid) and Goland (commercial hybrid). RESULTS: According to descriptive analysis, genetic variance affected few attributes describing Toscano and San Daniele ham sensory quality. The commercial hybrid Parma ham was distinct from the traditional one, the Goland genotype being significantly higher in red color, saltiness, dryness and hardness and showing a lower intensity of pork-meat odor/flavor and sweetness than the IL×LW genotype. Consumer acceptance was mainly influenced by the PDO technology. A genotype effect on acceptance was only observed in Toscano ham. Principal component regression analysis revealed that Toscano ham was the preferred sample. Considering that the consumers involved were from Tuscany, it is likely that Toscano ham was preferred owing to their higher familiarity with this product. CONCLUSION: Sensory properties of ham samples were better discriminated according to their PDO than their genotype. Likewise, consumer liking was more affected by the specific PDO technology than by genetic type. Toscano ham was the most preferred and most familiar product among Tuscan consumers, indicating that familiarity with the product was the best driver of dry-cured ham preference.
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Comportamento do Consumidor , Manipulação de Alimentos/métodos , Genótipo , Carne/análise , Sensação , Sus scrofa/genética , Animais , Cruzamento , Cultura , Humanos , Itália , Produtos da Carne/análise , Olfato , Especificidade da Espécie , PaladarRESUMO
The main elemental constituents (H, C, N, O, and S) of bio-organic material have different stable isotopes (2 H, 1 H; 13 C,12 C; 15 N,14 N; 18 O,17 O,16 O; 36 S, 34 S, 33 S, and 32 S). Isotopic ratios can be measured precisely and accurately using dedicated analytical techniques such as isotope ratio mass spectrometry (IRMS). Analysis of these ratios shows potential for assessing the authenticity of food of animal origin. In this review, IRMS analysis of food of animal origin and variability factors related to stable isotope ratios in animals are described. The study also lists examples of application of stable isotope ratio analysis to meat, dairy products, fish, and shellfish and emphasizes the strengths and weaknesses of the technique. Geographical, climatic, pedological, geological, botanical, and agricultural factors affect the stable isotope ratios (SIR) of bio-elements, and SIR variations are ultimately incorporated into animal tissue through eating, drinking, breathing, and exchange with the environment, being recorded in the resulting foods. SIR analysis was capable of determining geographical origin, animal diet, and the production system (such as organic/conventional or wild/farmed) for pork, beef, lamb, poultry, milk, butter, cheese, fish, and shellfish. In the case of the hard PDO (protected designations of origin) cheeses Grana Padano and Parmigiano Reggiano it is also used in real-life situations to assess the authenticity of grated and shredded cheese on the market.
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Abundance of native pastures makes Cameroon's western highland savannah (WHS) a hotspot for low-input beef-type cattle. Dumbo Ranch is central to cattle seed stock multiplication in WHS and holds that Dermatophilus congolensis infection undermines production. The bovine BoLA-DRB3 has been variously demonstrated as the principal gene of the major histocompatibility locus associated with immunity and resistance to dermatophilosis in cattle. We studied the profile of dermatophilosis prevalence in zebu Goudali (G) and its Simmental composite, SimGoud (SG), at Dumbo Ranch and determined the distribution of a dermatophilosis-associated susceptibility allele of the BoLA-DRB3 gene by allele-specific polymerase chain reaction (PCR). We recorded a 42 % prevalence of dermatophilosis in the studied cohort (337 animals). Dermatophilosis was more common in older cattle than in cattle ≤36 months (p ≤ 0.05). G was more affected compared to SG, because of the prevalence of the disease in the oldest animals and the age distribution of the experimental subjects. No susceptible homozygote was observed. About 85 and 15 % of the cohort carried the homozygous resistant and heterozygous condition, respectively. This genotype distribution was not affected by cattle type. The study confirms the presence of dermatophilosis among G and SG cattle in WHS. However, there was no correlation between the presence of the disease-associated susceptible allele considered and clinical manifestation. Screening for this dermatophilosis resistance-associated allele of BoLA-DRB3 gene appeared not useful for selection of G and SG in WHS.
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Infecções por Actinomycetales/veterinária , Criação de Animais Domésticos , Doenças dos Bovinos/epidemiologia , Suscetibilidade a Doenças/veterinária , Bactérias Gram-Positivas/imunologia , Dermatopatias Bacterianas/veterinária , Infecções por Actinomycetales/epidemiologia , Alelos , Animais , Camarões/epidemiologia , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/genética , Doenças dos Bovinos/imunologia , Feminino , Genótipo , Antígenos de Histocompatibilidade Classe II/genética , Masculino , Reação em Cadeia da Polimerase , Prevalência , Dermatopatias Bacterianas/epidemiologia , Clima TropicalRESUMO
European consumers are more and more aware of the credence attributes of foods, particularly of those of animal origin. The aim of the paper was to assess whether the information about production system may modify the consumer liking of cheese. Montasio PDO cheese (MC), usually made by milk from indoor reared cows of different breeds, was processed from pure milk of Italian Simmental (IS) cows (ISMC) or of IS cows grazing on mountain pasture (ALP-ISMC). A consumer test was carried out in two sessions on 60-d ripened cheeses. In the first, both cheeses were tasted by Montasio consumers in blind condition (Perceived liking, PL). Then the respondents were asked to read information about the breed and the rearing system and to give their Expected liking (EL). Two weeks after, in the second session, the same consumers tasted the two cheeses with the linked information (Actual liking, AL). Despite the similar PL average score (ISMC: 21±2·3 vs. ALP-ISMC: 23±2·2 points on Labelled Affective Magnitude scale, P>0·05), it was possible to identifying consumers' clusters with differential liking for the two types of Montasio PDO, that were characterised by different physico-chemical properties. Consumers express a high EL for ISMC (38±2·6 points) and even more for ALP-ISMC (61±2·5 points). The AL of ISMC (35±2·1 points) was similar and statistically not different from the EL (complete assimilation of information about breed). For ALP-ISMC the assimilation was complete for consumers (29%) who have expressed a positive PL for it, at least twice as much than ISMC. For the rest of consumers, both information and intrinsic properties play a significant role in the AL of the pasture-derived cheese.
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Cruzamento , Bovinos/crescimento & desenvolvimento , Bovinos/genética , Queijo , Comportamento do Consumidor , Animais , Queijo/análise , Queijo/classificação , Fenômenos Químicos , Rotulagem de Alimentos , Preferências Alimentares , Humanos , Itália , Leite , Reologia , PaladarRESUMO
Dairy cattle in the Alps are traditionally maintained on high altitude pastures during summer. In recent decades, however, many farmers prefer to maintain the cows always indoor with a hay-based diet. Many authors have shown that the forage type is able to modify the characteristics of milk and cheese. Recently the product specification of PDO Montasio allowed differentiation between mountain cheeses and other products. Aim of this trial is to study the effect of rearing system on the characteristics of milk and cheese produced in this context. One hundred and twenty Simmental dairy cows were considered, 60 grazed on high altitude pasture, and 60 kept indoor and fed a hay-based diet. Cheese production was repeated in two periods (early July and late August) and ripened two and six months. Pasture-derived milk and cheese presented higher fat and lower protein content than hay-derived ones. Rearing systems also affected cheese colour. Textural parameters, hardness, gumminess and chewiness were found to be higher in pasture-derived cheese. In addition, it showed lower level of total saturated fatty acids, and higher level of mono and polyunsaturated fatty acids than hay-derived cheeses. Consumers perceived the difference of cheeses in terms of colour and holes, but they express a similar overall liking. More limited effects of period and ripening time were observed.
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Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Queijo/análise , Abrigo para Animais , Leite/química , Animais , Queijo/normas , Indústria de Laticínios/métodos , Ácidos Graxos/química , Feminino , Análise de Alimentos , Análise de Componente PrincipalRESUMO
Alpine pastures have not yet been extensively studied with regard to the presence of alkaloids in herbaceous plants. In this work the alkaloid profiles were characterised from a selection of 62 herbs collected from alpine pastures in north-eastern Italy. High-performance liquid chromatography coupled to a hybrid quadrupole-orbitrap mass spectrometer was used to evaluate the presence of 41 different alkaloids and quantify them using a targeted approach. Provisionally, 118 alkaloids were identified, including both free and glycosylated forms, making use of a homemade database and a suspect screening approach. rucifoline, gramine, heliotrine, lycopsamine, seneciphylline, and veratramine were quantified with concentrations ranging from 6 to about 100 µg kg-1 in 6 plants. Herbaceous plants belonging to the most well-represented plant families (Poaceae, 9 species; Asteraceae, 7; Lamiaceae, 6) showed distinct and characteristic alkaloid profiles and were correctly reclassified with an average accuracy of 85% (Partial Least Squares - Discriminant Analysis).
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Alcaloides , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Alcaloides/análise , Extratos Vegetais/química , Plantas , Cromatografia Líquida de Alta Pressão/métodosRESUMO
The development of balanced, healthy, ready-to-consume, and easy-to-prepare products has led to the development of new food technologies. Despite their high commercial value, bullfrog (Aquarana catesbeiana) carcasses result in low yields, with the thighs being the most marketed in comparison to other carcass portions. In this sense, liver pâté is a traditional food consumed worldwide, mainly in European countries, and may be prepared by incorporating bullfrog meat by-products and certain viscera. In this context, the aim of the present study was to develop a pâté product based on a mixture comprising 50% grounded bullfrog torso meat and 50% liver paste, with each treatment incorporating 10% liver paste increments, totaling five final mixtures. The nutritional compositions and physicochemical, microbiological, and toxicological characteristics of each mixture were assessed. The dry matter percentage of the prepared product was determined to be 27.00%, while mineral content was 1.45%, lipid content was 4.00%, and total protein content was 20.00%. Finally, microbiological counts were in agreement with current food safety regulations. The developed pâté serves as a standard, recycling underused industrial materials, adding value to the production chain at low operational costs, creating a more accessible market, and promoting the popularization of this type of meat.
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Cull dairy cows are important contributors to total beef production in the USA and in Europe. Hempseed cake is a by-product of oil production and it is rich in unsaturated fatty acids (FA). This study aimed to investigate the effect of adding hempseed cake to the diet of Italian Simmental (IS) cull dairy cows on performances and meat quality. Twenty-six cull dairy cows were divided into three dietary groups: hay-based, corn silage-based and pasture-based diets. Within each group, the animals were equally divided into two treatments according to the protein source of the concentrate: hempseed cake (HEMP) or soybeans meal (SB). The trial lasted four months. HEMP showed similar in vivo performance and carcass characteristics, such as average daily gain (p > 0.05) and dressing percentage (p > 0.05), compared with SB. Meat characteristics, such as ether extract content and Warner−Bratzler shear force, were also similar between experimental groups (p > 0.05). Considering FA composition, HEMP showed similar saturated FA and polyunsaturated FA content (p > 0.05) but lower desirable fatty acids (p < 0.05) content and a tendentially lower hypocholesterolemic/hypercholesterolemic ratio (p < 0.10) than SFA. Hempseed cake can substitute soybean in the diet of cull dairy cows without effects on performance or meat quality.
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One of the crucial public health problems today is the emerging and re-emerging of multidrug-resistant (MDR) bacteria coupled with a decline in the development of new antimicrobials. Non-typhoidal Salmonella (NTS) is classified among the MDR pathogens of international concern. To predict their MDR potentials, 23 assembled genomes of NTS from live cattle (n = 1), beef carcass (n = 19), butchers' hands (n = 1) and beef processing environments (n = 2) isolated from 830 wet swabs at the Yaounde abattoir between December 2014 and November 2015 were explored using whole-genome sequencing. Phenotypically, while 22% (n = 5) of Salmonella isolates were streptomycin-resistant, 13% (n = 3) were MDR. Genotypically, all the Salmonella isolates possessed high MDR potentials against several classes of antibiotics including critically important drugs (carbapenems, third-generation cephalosporin and fluoroquinolone). Moreover, >31% of NTS exhibited resistance potentials to polymyxin, considered as the last resort drug. Additionally, ≤80% of isolates harbored "silent resistant genes" as a potential reservoir of drug resistance. Our isolates showed a high degree of pathogenicity and possessed key virulence factors to establish infection even in humans. Whole-genome sequencing unveiled both broader antimicrobial resistance (AMR) profiles and inference of pathogen characteristics. This study calls for the prudent use of antibiotics and constant monitoring of AMR of NTS.
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Cathepsin B activity was measured during processing in hams originating from the main Italian prosciutto PDOs: Parma, San Daniele and Toscano. Sixty-five heavy pig thighs, from sixty-five Italian large white x Italian Landrace pigs bred and slaughtered in the same conditions were considered. Five thighs represented the post-mortem control time. The other 60 were distributed one plant per PDO, following a balanced plan. The thighs were sampled at the biceps femoris in groups of four per plant in the following ripening phases: salting, resting, drying, greasing, end of curing. The activity of the Cathepsin B (U/g protein) was determined by means of fluorescence measurements. The Cathepsin B ripening trend of the various PDOs was significantly different, particularly during the initial and mid-curing stage. This activity correlates with the proteolysis index through a PDO dependent pattern, indicating that different processing conditions can influence the quality of prosciutto, since they determine its biochemical development.
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The contribution of dietary fatty acids to the quality of the meat and their path through the bovine organism is currently the subject of a lot of research. Stable isotope ratio analysis represents a powerful tool for this aim, one that has not been studied in depth yet. In this work, for the first time, the carbon isotopic ratios of six fatty acids (myristic 14:0, palmitic 16:0, stearic 18:0, oleic 18:1n-9, linoleic 18:2n-6 and linolenic 18:3n-3 acids) in different matrixes (diet, rumen, duodenal content, liver and loin) were analysed through gas chromatography combustion isotope ratio mass spectrometry. Moreover, the quantification of the single fatty acids was carried out, providing important information supporting the carbon isotopic ratio results. The variation in the concentration of the fatty acids in the different matrices depends on the chemical modifications they undergo in the sequential steps of the metabolic path. GC-C-IRMS turned out to be a powerful tool to investigate the fate of dietary fatty acids, providing information about the processes they undergo inside the bovine organism.
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Isótopos de Carbono/análise , Fracionamento Químico/métodos , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Marcação por Isótopo , Animais , Bovinos , Dieta , Duodeno/metabolismo , Fígado/metabolismo , Rúmen/metabolismoRESUMO
Tannins are compounds able to form complexes with proteins limiting their ruminal degradation and thus the synthesis of some odour-active compounds may be inhibited. Tannins are broadly divided in condensed tannins (CT) and hydrolysable tannins (HT). The study aimed to assess the influence of dietary inclusion of three commercial tannin extracts, namely mimosa (Acacia mearnsii; CT), chestnut (Castanea sativa; HT) or tara (Caesalpinia spinosa; HT) on volatile profile and flavour of meat and kidney fat from lambs. Comisana male lambs were divided into four groups (n = 9 each) and fed for 75 days with a concentrate-based diet (CON) or CON supplemented with 4% of one of the tannin extracts. Tannins reduced "pastoral" odour in perirenal fat of lambs the meat of which was characterized by a very low perception of this attribute. It may be assumed that p-cresol and 8-methylnonanoic acid mostly contributed to "pastoral" odour expression in the diet without condensed or hydrolysable tannins.
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Taninos Hidrolisáveis/administração & dosagem , Proantocianidinas/administração & dosagem , Carne Vermelha/análise , Acacia/química , Ração Animal/análise , Animais , Dieta/veterinária , Fabaceae/química , Fagaceae/química , Humanos , Masculino , Odorantes , Carneiro Doméstico , Taninos , Paladar , Compostos Orgânicos Voláteis/análiseRESUMO
The present study aimed to assess the effect of information about organic production on Pecorino cheese liking and consumer willingness to pay. Mean scores of perceived liking were similar for organic cheese (OC) and conventional cheese (CC). Expected liking scores were higher for OC than for CC (P<0.001). For OC the expected liking was significantly higher (P<0.001) than the perceived liking expressed in blind conditions (negative disconfirmation), whereas for CC the expected liking was significantly lower (P<0.001) than the perceived liking expressed in blind conditions (positive disconfirmation). Consumers assimilated their liking for OC in the direction of expectations, as the difference actual vs. perceived liking was significant (P<0.001). However the assimilation was not complete, as also the difference actual liking vs. expected liking was significant (P<0.001). Consumers showed a willingness to pay OC (mean+/-se=4.20+/-0.13 euro/100 g) higher than the local retail price for conventional (1.90 euro/100 g) and even organic cheese (3.00 euro/100 g). We conclude that the information about organic farming can be a major determinant of cheese liking and consumer willingness to pay, thus providing a potential tool for product differentiation, particularly for small scale and traditional farms.
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Queijo , Preferências Alimentares , Alimentos Orgânicos , Adulto , Fatores Etários , Queijo/economia , Custos e Análise de Custo , Feminino , Alimentos Orgânicos/economia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The aim of this study was to assess the effect of heat stress on dairy cow performance and on the expression of selected genes involved in milk protein metabolism. Eight Italian Holstein Friesian cows were kept under thermoneutral conditions (temperature-humidity index (THI) < 72, CON) for 8 days and under mild heat stress conditions (72 < THI < 78, HS) for an additional 8 days. The rectal temperature, feed intake, and milk yield were recorded during the last 3 days of the CON and HS periods. During the same time period, milk samples were collected to assess the composition and expression of selected genes involved in milk protein metabolism. Gene expression analyses were performed on somatic cells from milk, which are representative of mammary tissue. In terms of dairy cow performance, HS resulted in lower milk and protein yields and feed intake but higher rectal temperature than for CON (p < 0.05). Under HS, there were greater abundances of HSPA1A (p < 0.05) and BCL2 (p < 0.05), compared to CON, but similar levels of CSN2 (p > 0.05), CSN3 (p > 0.05), HSPA8 (p > 0.05), and STAT5B (p > 0.05) mRNA. Mild heat stress reduced the performance of dairy cows without affecting the expression of genes coding for caseins.
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We aimed to investigate whether the sensitivity to capsaicin had an effect on pungency perception of pasta filata cheeses. In addition, we assessed the effect of several individual variables (gender, age, consumer provenance, PROP status and personality traits) on both consumer liking and choice for pasta filata cheeses. Four pasta filata cheeses at two ripening times and 272 subjects from three different Italian locations were used. Based on sensory data, the PCA discriminated sweet (ripened at 2 months) from pungent cheeses (ripened at 12 months). Cheese pungency perception increased with increasing sensitivity to capsaicin (P < 0.001). There was no clear relationship between sensitivity to capsaicin or sensitivity to cheese pungency with cheese liking, whereas a number of other aspects, including sensory attributes and individual consumer characteristics, such as consumer provenance (P < 0.001), gender (P < 0.001) and food neophobia (P < 0.05), affected the liking for different pasta filata cheeses. Consumers who were younger (18-30 y.o.; P < 0.05), female (P < 0.001), unfamiliar with pungent foods (P < 0.0001) and consumers from Potenza (P = 0.001) more often declared to prefer sweet over pungent cheese, whereas in terms of real choice supertasters and neophobic subjects chose the sweet option more often (P = 0.01). In conclusion, sensitivity to capsaicin affected pungency perception in pasta filata cheese, whereas no clear relationship was observed between pungency perception and liking. The contribution of cheese and consumer characteristics on cheese liking and choice in addition to pungency, was confirmed by the differences in declared and real choice for sweet or pungent cheeses.