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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

An?lise de ecoefici?ncia do consumo de ?gua e energia na ind?stria de latic?nios no licenciamento ambiental no estado da Bahia

Fonseca, Jos? Carlos Jesus da 11 August 2017 (has links)
Submitted by Jadson Francisco de Jesus SILVA (jadson@uefs.br) on 2018-04-10T23:18:39Z No. of bitstreams: 1 Jose Carlos - Disserta??o - Vers?o Final 2017 B.pdf: 1422782 bytes, checksum: 8058051bfe780cb7972b630af8f1e7e0 (MD5) / Made available in DSpace on 2018-04-10T23:18:39Z (GMT). No. of bitstreams: 1 Jose Carlos - Disserta??o - Vers?o Final 2017 B.pdf: 1422782 bytes, checksum: 8058051bfe780cb7972b630af8f1e7e0 (MD5) Previous issue date: 2017-08-11 / The dairy industry is an example of a system characterized by the association of different production systems: agriculture, livestock, dairy, industrial transformation and product distribution. Dairy products are the food group that includes milk, as well as its processed byproducts, having as main inputs, water and energy. These inputs are essential in the production processes of the dairy industry, as well as the assessment of eco-efficiency through the quantities of water and energy consumed. For this purpose, data from 23 dairy products registered at INEMA from 2006 to 2012 were used, and the average water consumption coefficient of 3.15 LL of processed milk and average effluent generation coefficient of 3.17 LL processed milk. Regarding the energy consumed indicator, the available data were unsatisfactory due to lack of data, which made it impossible to obtain reliable results on consumption. It was concluded that the dairy products licensed in the state of Bahia are less efficient in the use of water and energy inputs in relation to the national industry, as it is in relation to the international industry (benckmarking). It is pointed out that this type of approach is not yet an initiative of the Environmental Agency and that the concept of eco-efficiency is not incorporated in the analyzes of environmental licensing in Brazil. / A industria de latic?nios ? um exemplo de sistema caracterizado pela associa??o de diferentes sistemas de produ??o: agricultura, pecu?ria, explora??o leiteira, transforma??o industrial e distribui??o do produto. Os produtos l?cteos s?o o grupo de alimentos que inclui o leite, assim como os seus derivados processados, tendo como insumos principais, ?gua e energia. Esses insumos s?o essenciais nos processos produtivos da ind?stria de produtos l?cteos, assim como a avalia??o da ecoefici?ncia atraves das quantidades de ?gua e energia consumidas. Para este fim, foram utilizados dados de 23 latic?nios protocolados no INEMA, no per?odo de 2006 a 2012, sendo obtido o coeficiente m?dio de consumo de ?gua de 3,15 L.L de leite processado e coeficiente m?dio de gera??o de efluente de 3,17 L.L leite processado. Quanto ao indicador de energia consumida, os dados disponibilizados foram insatisfat?rios devido ? falta de dados, o que impossibilitou a obten??o de resultados confi?veis sobre o consumo. Concluiu-se que os latic?nios licenciados no estado da Bahia s?o menos eficientes na utiliza??o dos insumos de ?gua e energia em rela??o ? ind?stria nacional, da mesma forma que esta em rela??o ? ind?stria internacional (benckmarking). Indica-se que esse tipo de abordagem ainda n?o ? uma iniciativa do ?rg?o Ambiental e que o conceito de ecoefici?ncia n?o est? incorporado nas an?lises do licenciamento ambiental, no Brasil.
212

Cultures antifongiques applicables comme ferments de bioprotection dans les produits laitiers : sélection, évaluation à l'échelle pilote et identification de composés supports de l'activité / Antifungal microorganisms applicable as bioprotectivecultures in diary products : selection, pilot-scale evaluation and identification of the compounds supporting the activity

Leyva Salas, Marcia 06 November 2018 (has links)
La contamination fongique des produits laitiers est à l’origine de pertes économiques conséquentes et de gaspillage alimentaire. Dans un contexte de demande pour plus de « naturalité », les cultures de bioprotection et leurs métabolites représentent une alternative d’intérêt aux conservateurs chimiques pour lutter contre ces contaminants.Les objectifs de cette thèse étaient i) de sélectionner des micro-organismes présentant une activité antifongique, pour élaborer des cultures de bioprotection applicables dans des produits laitiers, et ii) d’étudier les composés potentiellement supports de l’activité antifongique observée. Dans un premier temps, l’activité antifongique de 32 souches de bactéries lactiques et propioniques a été étudiée en modèles « fromage » et « yaourt ». L’étude de combinaisons de souches et de leur innocuité a conduit à sélectionner 2 combinaisons binaires de lactobacilles (A1 et A3). Leur efficacité et applicabilité a été évaluée à l’échelle pilote en fabrication de crème fraîche et de fromage.Les challenges tests et tests d’usages ont montré que selon le produit laitier, A1 et A3 ont une activité antifongique similaire ou supérieure que les cultures bioprotectrices commerciales. Selon l’inoculum ajouté, ces cultures n’impactent pas les caractéristiques technologiques et organoleptiques des produits laitiers. Des méthodes chromatographiques des composés antifongiques suivies d’analyses statistiques ont permis de mettre en évidence des « cocktails » de 2 à 17 composés, selon la matrice et la culture considérée, qui sont probablement supports de l’activité antifongique.Ces travaux contribuent à une meilleure compréhension des mécanismes d’action de l’activité antifongique et devraient conduire au développement de cultures antifongique pour remplacer les conservateurs dans les produits laitiers. / Fungal contamination of dairy products is responsible for economic losses and food waste. In a context of “preservative-free” product demand, bioprotective cultures and their metabolites represe,t an alternative of interest of chemical preservatives to control these spoilers.The objective of this study was i) to select microorganisms exhibiting an antifungal activity, in order to elaborate bioprotectivecultures applicable in dairy products, and ii) to study the compounds potentially supporting the observed activity. Firstly, the antifungal activity of 32 strains of lactic acid and propionic bacteria screened in cheese model and yogurt. Strain combinaison study and safety assessment led to the selection of 2 binary lactobacilli combinations (A1 and A3). Their efficiency and applicability were then evaluated in pilot-scale productions of sour cream and cheese.Challenge and shelf life tests showed that depending on the dairy product, A1 and A3 have a similar or higher antifungal activity than the commercial bioprotective cultures. In addition, depending of inoculum, A1 and A3 did not impact the technological and organoleptic characteristics. Chromatographic methods and statistical analyses allowed identifying cocktails of 2 to 17 compounds, according to the considered dairy product and culture that probably support the antifungal activity.The obtained results contribute to a better understanding of the antifungal activity action mechanisms and should lead to the development of antifungal cultures to replace preservatives in dairy products.
213

Consumo de produtos lácteos informais, um perigo para a saúde pública. Estudo dos fatores relacionados a esse consumo no município de Jacareí - SP / Consumption of informal dairy products, a hazard for public health. Study of factors related to this consumption at the city of Jacareí – SP

Sousa, Danielle Daher Pereira de 06 December 2005 (has links)
Com o objetivo de estabelecer associações entre as características dos consumidores de produtos lácteos com a preferência pelo produto lácteo formal ou informal, as razões para essa preferência, o hábito de fervura do leite dentre os consumidores de informal, os principais produtos lácteos consumidos, o conhecimento sobre as doenças transmitidas pelo leite e derivados e o significado do carimbo do Serviço de Inspeção, para que pudessem servir de base para ações futuras de intervenção para a redução do consumo de informais, realizou-se um levantamento utilizando um questionário semi-estruturado, com 29 questões, aplicado a 465 consumidores em diferentes pontos comerciais do município de Jacareí, no período de novembro de 2004 a fevereiro de 2005. Os resultados mostraram associação entre o consumo do produto informal e as características: sexo masculino, local de moradia zona rural, renda familiar acima de R$ 1.040,00, mais de 4 pessoas morando no domicílio, compra de ambulantes, compra na zona rural e o conhecimento sobre a possibilidade do produto lácteo poder causar doenças. Associada ao consumo de produtos formais esteve apenas a variável compra em supermercado.Os produtos lácteos informais mais consumidos foram o leite fluido, queijo minas frescal, manteiga e iogurte. Dos consumidores de leite fluido 7,4% consomem leite informal sem ferver. As principais razões para o consumo do informal foram: ser mais puro, mais fresco, mais barato, mais forte, ter confiança em quem vende o produto, não ter diferença do industrializado, ser mais saudável e mais saboroso. Para os derivados formais, obteve-se primeiro a praticidade, seguida pela segurança ou procedência, higiene, não encontrarem do produtor, ser tratado ou testado, o costume, o sabor e o preço. Aproximadamente 17% dos consumidores alegaram procurar pelos carimbos da Inspeção na embalagem ao comprar leite ou derivados, no entanto nenhum consumidor se lembrou dos carimbos quando perguntados o que observavam na embalagem no ato da compra de produtos industrializados. Os meios de divulgação de informação escolhidos, em ordem de freqüência, foram: TV, rádio e através das escolas do ensino fundamental. Conclui-se que o consumo de produto lácteo informal independe de qualquer das variáveis estudadas, embora haja maior freqüência de consumo de informais entre homens, entre as pessoas que moram na zona rural, famílias com renda mais alta, maior número de pessoas por domicílio, quando há compra de ambulantes ou na zona rural e entre as pessoas que alegam ter conhecimento de que o leite transmite doenças; 7,4% dos entrevistados estão expostos ao risco de contrair alguma zoonose ou outra doença pelo consumo de leite cru sem ferver. A população precisa ser esclarecida sobre as reais diferenças entre os produtos industrializados e os informais, bem como sobre os órgãos que atestam a qualidade dos alimentos. A redução do risco será alcançada quando governo e indústria trabalharem, sistemática e continuamente, para mudar paradigmas e motivar mudança de hábitos / Intending to establish associations between dairy product consumers’ characteristics and the preference for a formal or informal dairy product, the reasons for this preference, the habit of boiling the milk among the informal product’s consumers, the main consumed dairy products, knowledge about milk and dairy product borne diseases and the meaning of the Inspection Service’s seal, so they could be a base for future intervention actions to reduce informal product consumption, a survey was carried out using a 29-question semi-structured questionnaire applied to 465 consumers at different points of sale in the city of Jacareí-SP-Brazil from November 2004 to February 2005. The results showed an association between the consumption of the informal product and the following characteristics: male, rural area residence, family income above R$ 1,040.00, more than 4 residents, purchase from street vendors, purchase in the rural area and knowledge that the dairy product can cause diseases. Only the supermarket purchase variable was associated to formal product consumption. The most consumed informal dairy products were: liquid milk, fresh white cheese, butter and yogurt. 7.4% of the liquid milk consumers consume raw milk without boiling it. The main reasons for consuming the informal dairy product were: for being purer, fresher, cheaper, stronger, for trusting who sells the product, for not being different from the industrialized product and for being healthier and tastier. For the formal dairy products, first came practicality, then safety or origin, hygiene, not finding from the producer, being treated or tested, custom, taste and price. About 17% of the consumers said they look for the Inspection seals on the package when they buy milk or dairy products; however no consumer remembered the seal when asked what they observed on the package upon buying industrialized products. The chosen disclosure means, in order of frequency were: TV, radio and through middle schools. The conclusion is that the consumption of informal dairy products does not depend on any of the studied variables, although there is a higher frequency of informal dairy product consumption among men, among those who live in the rural area, families with higher income, higher number of residents per house, when purchased from street vendors and in the rural area and among people who say they know that milk spreads diseases; 7.4% of those interviewed are exposed to the risk of getting some zoonosis or other disease by consuming raw not-boiled milk. The population must be informed about the real differences between industrialized and informal dairy products, as well as about the authorities that certify food quality. Risk reduction will be reached when the government and industry systematically and continuously work to change paradigms and motivate habit changes
214

Propriétés antifongiques de bactéries lactiques isolées de laits crus / No

Delavenne, Emilie 16 March 2012 (has links)
Les produits laitiers fermentés tels que les yaourts, les laits fermentés et les fromages frais, occupent une place importante dans l’économie française. La stabilité de ces produits et leurs chances d’exportation sont cependant limitées par de fréquentes altérations fongiques. De plus, l’augmentation des résistances de certains champignons aux conservateurs chimiques ainsi que la forte demande des consommateurs pour des produits dépourvus d’additifs poussent les industriels à en réduire l’ajout. Dans ce contexte, il est nécessaire de développer des alternatives innovantes, telle que la bio-conservation. Les bactéries lactiques, utilisées depuis des millénaires dans la fermentation de nombreux aliments, et généralement reconnues comme inoffensives pour la santé, sont potentiellement de bonnes candidates pour la bio-conservation. Dans le but d’obtenir une ou deux souches de bactéries lactiques antifongiques, capables d’être compétitives au sein de produits laitiers fermentés tels que le yaourt, une collection de bactéries lactiques antifongiques a d’abord été constituée. Pour cela, un criblage de colonies isolées de laits crus de vache, de chèvre et de brebis a été effectué sur une période d’une année. Ce criblage, ciblé contre 4 champignons communément retrouvés dans les produits laitiers contaminés, a abouti à l’isolement de 1235 colonies de bactéries lactiques antifongiques. Ceci a permis d’évaluer la biodiversité des bactéries lactiques antifongiques d’une part, et celle des champignons, d’autre part, dans ces échantillons de lait, afin d’observer une éventuelle corrélation entre la présence de champignons et l’expression des activités antifongiques. L’influence de l’origine du lait, de la période d’échantillonnage, du milieu d’isolement et du champignon ciblé, sur le pourcentage de colonies actives isolées a été mise en évidence. Parmi les champignons ciblés, Pénicillium expansum était le plus facilement inhibé, et la majorité des colonies ont été isolées durant la troisième période d’échantillonnage, majoritairement sur les milieux à base de MRS. Les laits de vache et de chèvre se sont révélés être des réservoirs de bactéries lactiques antifongiques, contrairement aux laits de brebis. La majorité des bactéries lactiques antifongiques isolées et identifiées appartenait au genre Lactobacillus, majoritairement du groupe Lb. casei. Onze isolats, dont 10 appartenant au groupe Lb. casei, ont été sélectionnés selon l’intensité de leur activité antifongique et leur spectre d’action sur milieu MRS. Certaines de leurs propriétés technologiques ont été caractérisées, en vue de leur utilisation comme cultures protectrices dans des produits laitiers fermentés. Leur activité antifongique a également été testée dans le lait et dans le yaourt, contre 6 contaminants fongiques communément responsables d’altérations dans les yaourts. Une souche, Lb. harbinensis K.V9.3.1Np, a révélé de fortes activités antifongiques dans le yaourt contre 6 cibles fongiques. Les études complémentaires effectuées ont permis de montrer que la variation de certains paramètres technologiques (présence ou absence de saccharose, temps de fermentation) n’avait pas d’influence sur l’activité antifongique de cette souche. La découverte du potentiel antifongique de Lb. harbinensis K.V9.3.1Np est innovante. Cette espèce, isolée pour la première fois en 2005 d’un produit fermenté végétal, n’avait encore jamais été décrite comme présentant des activités antimicrobiennes. Sa forte activité antifongique dans le yaourt fait de Lb. harbinensis K.V9.3.1Np un bon candidat pour la bioconservation de produit(s) laitier(s) fermenté(s). / Fermented dairy products such as yogurt, fermented milks and fresh cheeses are of great importance in the French economy. The stability of these products and export opportunities are however limited by frequent fungal spoilages. In addition, the increase of fungal resistances to Chemical preservatives and the strong consumer demand for products deprived of Chemical additives are pushing manufacturers to reduce the quantities of added Chemical preservatives in these products. In this context, it is necessary to develop alternatives to classical food preservation methods, such as biopreservation. Lactic acid bacteria (LAB), used for millennia for diverse food fermentations, and generally recognized as safe for human health, can potentially be used for biopreservation. In order to select 1 or 2 LAB strains with antifungal activity capable to compete in fermented dairy products such as yogurt, a collection of antifungal LAB was first created. This was done by screening colonies isolated from cow, goat and ewe raw milk samples over a one-year period. This screening step, targeted against 4 fungi found in contaminated dairy products, resulted in the isolation of 1235 antifungal colonies. The biodiversity of the isolated antifungal LAB was then determined along with that of the fungi found in the different raw milks, in order to observe a possible correlation between the presence of fungi and the expression of antifungal activities. The influence of milk origin, sampling period, isolation medium and targeted fungus on the percentage of isolated active colonies was highlighted and clearly showed that both cow and goat milks were reservoirs of antifungal LAB. Among the targeted fungi, P. expansum was more easily inhibited, and the majority of colonies were isolated during the third sampling period, mainly on MRS-based media. The majority of identified antifungal LAB belonged to the genus Lactobacillus, mainly to the Lb. casei group. Eleven isolates, including 10 belonging to the Lb. casei group, were selected from these lactobacilli, according to their activity level and action spectrum in MRS medium. Some of their technological properties were characterized for their potential use as protective cultures in fermented dairy products and their antifungal activity was tested in milk and yogurt. To do this, 6 fungal contaminants commonly encountered in yogurt spoilage were used. A particular strain, Lb. harbinensis K.V9.3.1Np, showed a strong antifungal activity in yogurt. Additional experiments showed that the variation of technological parameters (presence or absence of sugar, fermentation time) had no influence on the antifungal activity of this strain. This is the first time that an antifungal potential has been observed for Lb. harbinensis, a species isolated for the first time in 2005 from a fermented vegetable product. Because of its effectiveness in yogurt, Lb. harbinensis K.V9.3.1Np is a promising strain for biopreservation of fermented dairy product(s).
215

Flavor development of cheddar cheese under different manufacturing practices

Lemus, Freddy Mauricio 19 September 2012 (has links)
Cheddar Cheese samples (good cheese, weak cheese, cheese made with pasteurized milk, cheese made with heat-shocked milk, cheese from production plant A, cheese from production plant B, cheese made with adjunct culture, and cheese made without adjunct culture), were evaluated during the ripening stage. Proteolysis was studied by a fractionation scheme, resulting in an insoluble fraction analyzed by urea polyacrylamide gel electrophoresis (Urea-PAGE), and a soluble fraction which was further investigated through water soluble nitrogen (WSN), trichloroacetic acid soluble nitrogen (TCA-SN) and phosphotungstic acid soluble nitrogen (PTA-SN) analyzed by total Kjeldahl nitrogen content (TKN). Reversed phase high performance liquid chromatography (RP-HPLC) was used to study the peptide profile of the water soluble fraction. Lipolyisis was studied by levels of individual free fatty acids determined through gas chromatography-flame ionization detection (GC-FID) after isolation employing solid phase extraction (SPE). Volatile sulfur compounds were studied using head space solid phase micro-extraction (SPME) coupled with gas chromatography-pulsed flame photometric detection (PFPD). It was found that Urea-PAGE is capable to differentiate samples according their age, but cannot discriminate samples regarding the treatment assessed, quality or origin of the samples. However, measurements of total Kjeldahl Nitrogen (TKN) of the WSN, TCA-SN, and PTA-SN fractions, and the principal component analysis of the RP-HPLC peptide profile of the WSN fraction, revealed differences in the rate and pattern of proteolysis for each one of the manufacturing cases. Good cheese, cheese produce in plant TCCA, cheese made in plant CRP with adjunct culture isolated from plant TCCA cheese, and cheese made with heat-shocked milk developed higher level of total nitrogen for the WSN, TCA-SN and PTA-SN fractions, indicating that primary and secondary proteolysis were faster for these samples. This is supported by a PCA model with three principal components that account for the 80-83% of the variability of the data from the RP-HPLC peptide profile analysis, which discriminates the samples according to age and manufacturing practice. In addition, FFA profiles demonstrated higher levels of low and medium chain free fatty acids for good cheese, cheese produce in plant TCCA, cheese made in plant CRP with adjunct culture, and cheese made with heat-shocked milk samples, which suggest faster lipolysis during ripening. The Volatile Sulfur Compounds (VSC) analysis showed higher levels of DMS and MeSH and lower levels of H2S, suggesting faster catabolism of sulfur containing amino acids in good cheese, cheese produce in plant TCCA, cheese made in plant CRP with adjunct culture, and cheese made with heat-shocked milk. / Graduation date: 2013
216

Ενεργειακή αξιοποίηση ληγμένων γαλακτοκομικών προϊόντων των μέσω αναερόβιας συγχώνευσης με αγροτοκτηνοτροφικά απόβλητα και παραγωγή εδαφοβελτιωτικού υψηλής προστιθέμενης αξίας με χρήση γαιοσκώληκων

Σταυρόπουλος, Κωνσταντίνος 30 March 2015 (has links)
Στην παρούσα εργασία, μελετήθηκε η διεργασία αναερόβιας χώνευσης ληγμένων γαλακτοκομικών προϊόντων καθώς και η συγχώνευσή τους με αγροτοκτηνοτροφικά απόβλητα. Αρχικά πραγματοποιήθηκε ο χαρακτηρισμός των αποβλήτων και των ληγμένων γαλακτοκομικών προϊόντων που χρησιμοποιήθηκαν. Σε επόμενο στάδιο έλαβαν χώρα πειράματα Βιοχημικού Μεθανογόνου Δυναμικού (BMP) με σκοπό τον καθορισμό του μεθανογόνου δυναμικού και την αξιολόγηση των υποστρωμάτων που αργότερα θα χρησιμοποιούνταν στους μεθανογόνους CSTR αντιδραστήρες. Μελετήθηκε έτσι η επίδραση της αύξησης της ποσότητας επεξεργασμένων και ανεπεξέργαστων γαλακτοκομικών προϊόντων που αντιστοιχούσε σε αύξηση της οργανικής φόρτισης με προσθήκη γαλακτοκομικών προϊόντων για τα συστήματα συνεχούς λειτουργίας. Σύμφωνα με τα πειράματα BMP, τα υποστρώματα με οξινισμένα γαλακτοκομικά προϊόντα σημείωσαν υψηλότερα ποσοστά παραγωγής μεθανίου. Η μέγιστη απόδοση που υπολογίστηκε αντιστοιχεί σε 634.06 mL CH4/g VSadd και αφορά το μίγμα του διβάθμιου συστήματος με τη μέγιστη ποσότητα γαλακτοκομικών - οργανικής φόρτισης. Στη συνέχεια έγινε σύγκριση της λειτουργίας μονοβάθμιου και διβάθμιου συστήματος επεξεργασίας μιγμάτων αγροτοκτηνοτροφικών αποβλήτων και ληγμένων γαλακτοκομικών προϊόντων. Όσον αφορά το διβάθμιο σύστημα, αυτό αποτελούταν από έναν οξεογόνο και ένα μεθανογόνο αντιδραστήρα. Σχετικά με τον οξεογόνο CSTR αντιδραστήρα μελετήθηκε η παραγωγή υδρογόνου με αξιοποίηση ληγμένων γαλακτοκομικών προϊόντων (93% γάλακτος - 5% γιαουρτιού - 2% αναρής) σε μεσόφιλες συνθήκες, pH 5.7 και σε δύο υδραυλικούς χρόνους παραμονής HRT 3d και 6d. Για HRT 3d σημειώθηκε παρεμπόδιση του συστήματος λόγω συσσώρευσης γαλακτικού οξέος. Η αύξηση του HRT σε 6 ημέρες ήταν αρκετή ώστε να αποφευχθεί η συσσώρευση του γαλακτικού οξέος και να διατηρηθεί ο μικροβιακός πληθυσμός με σκοπό να υπάρχει αξιοσημείωτη παραγωγή υδρογόνου. Η μέγιστη απόδοση σε υδρογόνο επιτεύχθηκε για υδραυλικό χρόνο παραμονής 3 ημερών και υπολογίστηκε ίση με 0.757 mol H2 / mol καταναλισκόμενων υδατανθράκων, ενώ η απόδοση σε υδρογόνο ήταν ελαφρώς χαμηλότερη για HRT 6d (0.676 molH2 /mol καταναλισκόμενων υδατανθράκων). Στη συνέχεια συγκρίνοντας τη λειτουργία των δύο μεθανογόνων αντιδραστήρων παρατηρούνται σημαντικές διαφορές στην παραγωγικότητα σε βιοαέριο και μεθάνιο. Ειδικότερα, ο μεθανογόνος αντιδραστήρας του διβάθμιου συστήματος ανέδειξε υψηλότερους ρυθμούς παραγωγής βιοαερίου και μεθανίου σε όλα τα μελετώμενα σενάρια. Συγκεκριμένα, όσον αφορά το διβάθμιο αντιδραστήρα οι συντελεστές απόδοσης μεθανίου αυξάνονται με αύξηση του οργανικού φορτίου, με μεγαλύτερη τιμή αυτή των 513.51 mL CH4/g VSadd για την περίπτωση επεξεργασίας του μίγματος με την υψηλότερη οργανική φόρτιση. Από την άλλη μεριά, ο μονοβάθμιος αντιδραστήρας παρουσιάζει την μέγιστη απόδοση σε μεθάνιο για την περίπτωση της αύξησης της οργανικής φόρτισης κατά 40% και υπολογίστηκε ίση με 261.08 mL CH4/g VSadd. (όταν ο αντίστοιχος συντελεστής απόδοσης στο διβάθμιο είναι 386.07 mL CH4/g VSadd). Η μέση περιεκτικότητα του βιοαερίου σε μεθάνιο σε και για τους δύο αντιδραστήρες ανέρχεται σε 63.48%. Επιπλέον αξίζει να σημειωθεί ότι και για τους δύο μεθανογόνους αντιδραστήρες δεν παρουσιάστηκε παρεμπόδιση στη λειτουργία τους παρά τα υψηλά επίπεδα αμμωνίας, τα οποία αγγίζουν τα όρια παρεμπόδισης στο στάδιο της μεθανογένεσης (Hansen et al., 1998), (Benabdallah El Hadj et al., 2009). Τα παραπάνω αποτελέσματα υποδεικνύουν ότι για την επεξεργασία των συγκεκριμένων αποβλήτων-προϊόντων μέσω της διαδικασίας της αναερόβιας συγχώνευσης προτιμάται η χρήση του διβάθμιου συστήματος. Η άποψη αυτή ενισχύεται και αν υπολογίσει κάποιος και τα οφέλη από την παραγωγή του υδρογόνου μέσω της οξεογένεσης των ληγμένων γαλακτοκομικών προϊόντων. Κρίνοντας από τα χαρακτηριστικά των εκροών των μεθανογόνων αντιδραστήρων καλό θα ήταν να εφαρμοστούν στη συνέχεια περαιτέρω μέθοδοι επεξεργασίας τους για μεγαλύτερη μείωση του οργανικού φορτίου ή/και εκμετάλλευση της πλούσιας απορροής σε αμμωνία και φώσφορο για παραγωγή πλούσιων εδαφοβελτιωτικών. Έτσι στη συνέχεια μελετήθηκε η περαιτέρω επεξεργασία του υγρού κλάσματος της απορροής μέσω συστήματος μεμβρανών διήθησης και η επεξεργασία του στερεού κλάσματος με τη διαδικασία του vermin-composting για παραγωγή εδαφοβελτιωτικού. Στο τελικό διήθημα από τις μεμβράνες υπολογίστηκε μείωση του COD κατά 86.4% και των στερεών κατά 51.5% και έτσι μπορεί να χρησιμοποιηθεί στην άρδευση γεωργικών εκτάσεων, ενώ το συμπύκνωμα για να καλύψει απαιτήσεις σε νερό κατά τη διαδικασία της κομποστοποίησης (π.χ. έλεγχος υγρασίας). Το τελικό προϊόν της κομποστοποίησης είναι σταθεροποιημένο και πλούσιο σε Ν, P, Κ συστατικά. Συγκεκριμένα υπολογίστηκε πως το τελικό εδαφοβελτιωτικό διέθετε ολικό άζωτο (TKN) αυξημένο κατά 85.92%, ολικό φώσφορο (ΤΡ) κατά 52.44% και ολικό κάλιο (ΤΚ) κατά 123.7%. Τέλος έλαβε χώρα η μελέτη της επίδρασης του pH στην παραγωγή υδρογόνου από ληγμένα γαλακτοκομικά απόβλητα σε αντιδραστήρα συνεχούς λειτουργίας (CSTR) και σε μεσόφιλες συνθήκες (37οC) με υδραυλικό χρόνο παραμονής HRT 6d. Τα εξαγόμενα αποτελέσματα έδειξαν πως η μέγιστη απόδοση σε παραγωγή υδρογόνου σημειώθηκε για τιμή pH 5 και ήταν ίση με 1.268 mol H2/mol CHκαταν.. Ο ρυθμός παραγωγής υδρογόνου που μετρήθηκε σε αυτό το pH ήταν 0.851 LH2/LR•d. Το γαλακτικό οξύ ανιχνεύθηκε ως το κυρίαρχο ενδιάμεσο προϊόν, ενώ το βουτυρικό ως το κυρίαρχο τελικό μεταβολικό προϊόν σε όλα τα CSTR πειράματα μελέτης της επίδρασης του pH. Η αυξημένη παραγωγή υδρογόνου παρατηρήθηκε ότι συνδέεται κυρίως με την κατανάλωση του γαλακτικού οξέος με ταυτόχρονη παραγωγή του βουτυρικού οξέος και υδρογόνου. Ύστερα από λήψη και επεξεργασία αρκετών εργαστηριακών αποτελεσμάτων σχεδιάστηκε και κατασκευάστηκε πιλοτική μονάδα παραγωγής βιοαερίου από επεξεργασία των παραπάνω αποβλήτων – γαλακτοκομικών προϊόντων. Η λειτουργία της μονάδας έδωσε μία μέση απόδοση σε μεθάνιο ίση με 353 mL CH4/g VSadd (πολύ κοντά σε συμφωνία με την αντίστοιχη εργαστηριακής κλίμακας (312 mL CH4/g VSadd). / This study focused on the valorization of End of Life Dairy Products (EoL-DPs) and agro-industrial wastes (such as Cheese Whey (CW), Liquid Cow Manure (LCM), Poultry Waste (PW), Pig Manure (PM) and Slaughter House Wastes (SHW)). Especially, this work deals with the anaerobic co-digestion of EoL-DPs with agrowastes. Therefore, initially the physicochemical characterization of the waste streams and EoL-DPs took place. Subsequently, Biochemical Methane Potential tests took place in order to determine the methane production and the suitability of a given organic substrate during its anaerobic decomposition. The BMP assay has proved to be a relatively simple and reliable method to obtain the extent and rate of organic matter conversion to methane. Different mixtures of agro wastes with acidified or not EoL-DPs were subjected. The BMP batch tests with acidified EoL-DPs presented higher methane production rates. The maximum methane production rate was 634.06 mL CH4 /g VSadd and was related to the mixture of the two stage system with the maximum percentage of treated EoL-DPs. Anaerobic digestion experiments were carried out in parallel in a two-stage and a single-stage anaerobic system. The two-stage system consisted of an acidogenic CSTR-type reactor (R1-A) fed with a mixture of EoL-DPs (93% milk-5% yogurt-2% cheese) operating at controlled pH (5.7) and a methanogenic one (R1-M) operated at a slightly alkaline uncontrolled pH (between 7-8) at a Hydraulic Retention Time (HRT) of 37 days. The single-stage system consisted of a methanogenic CSTR type reactor (R2) treating a waste mixture with the same composition as R1-M, using untreated EoL-DPs, at HRT of 37 d. All three reactors were operated under mesophilic conditions (37oC). The first phase of continuous operation aimed at optimizing the performance of the acidogenic reactor by testing the system at different HRTs, i.e. 3 and 6 days. Operating R1-A at an initial HRT of 3d resulted to a gradual increase and accumulation of lactic acid (25g/L) in the reactor and to a zero biogas and hydrogen production. HRT was thus increased to 6d aiming to recover the system’s performance. The maximum hydrogen yield 0.757 mol H2/mol carbohydrate consumed was achieved at HRT 3d, whereas hydrogen yield was slightly lower at the higher HRT 6d (0.676 mol H2/mol carbohydrate consumed) The performance of the two methanogenic reactors (R1-M and R2) was compared using raw or pasteurized SHW (70o C for 1 h) and different levels of added EoL-DPs (acidified or not respectively). Both biogas and methane productivities were increased when pasteurized SHW and high concentration of EoL-DPs was used. Concerning the methanogenic reactor of the two stage sytem (R1-M) presented higher methane yields with increasing the organic loading. The maximum calculated methane yield was 513.51 mL CH4/g VSadd and was related to the case of maximum treated organic loading. On the other hand R2 noted the maximum methane yield for the case of a 40% increment of organic loading with a value of 261.08 mL CH4/g VSadd (while the corresponding methane yield for R1-M was 386.07 mL CH4/g VSadd). The average content of methane in the biogas for both reactors was 63.48%. It’s worth noting that no inhibition was observed in the performance of both R1-M and R2 despite the prevailing high concentration of ammonia (~4 g/L) (Hansen et al., 1998), (Benabdallah El Hadj et al., 2009). All the experiment data suggest that the two-stage system exhibited a higher performance for the treatment of these types of wastes than the single-stage system. The energetic performance of the two-stage system is even higher than the single-system’s if hydrogen production during acidogenesis is taken into account. In the present work, the final effluent, obtained from the anaerobic digestion treating a mixture of agro-wastes and EoL-DPs was treated further because of the fact that was not fit for recycling or disposal to the environment. For this purpose the application of a membrane system aimed at purifying the liquid fraction of anaerobic effluent, while the solid fraction treated further in a vermicomposting procedure by the use of epigeic earthworms i.e. Eisenia foetida. By using UF and NF membranes the COD dropped at 86.4%, whereas 51.5% removal of solids was observed, resulted in a final permeate stream of high quality and suitable for irrigation. Finally, concerning the compost procedure, an important increase by 85.92% in nitrogen (TKN), 52.44% in total phosphorus (TP) and 123.7% in total potassium (TK) content was observed in the vermireactor. Finally, the effect of pH during acidogenesis of the EoL-DPs mixture in the biological production of hydrogen and volatile fatty acids was investigated. CSTR acidogenic experiments of the dairy liquid mixture (93% milk – 5% yoghurt – 2% cheese) were performed at controlled pH values (4, 4.5, 4.7, 5, 5.3, 5.7), using a solution of 6N NaOH and KOH, under mesophilic conditions (37ºC) and a hydraulic retention time (HRT) of 6 days. The obtained results showed that the optimum conversion of substrate to hydrogen and the maximum hydrogen yield of 1.268 moles H2/ moles equivalent glucose was observed at pH= 5. The biogas produced from the acidogenic reactor consisted exclusively of hydrogen and carbon dioxide and was free of methane. The hydrogen production at pH 5 was fluctuating with a mean value of 0.851 L L-1reactor d-1 at steady state. Lactic acid was detected as the main intermediate acid, while the butyric acid as the main final volatile fatty acid. The increased hydrogen production was observed that is primarily associated with the consumption of lactic acid with simultaneous production of butyric acid and hydrogen. A pilot biogas plant was designed after the analysis of the experiments’ data. Pilot plant consists of two bioreactors and operates as a two stage system of anaerobic digestion of EoL-DPs and agrowastes. The operation of pilot plant promises similar performance in terms of methane yields (353 mL CH4/g VSadd – while the laboratory one was calculates at 312 mL CH4/g VSadd).
217

CLA as a nutraceutical molecule: concentration in foods, estimation of intake in Italy and genetic factors affecting thesynthesis in animal tissue

CICOGNINI, FRANCESCA MARIA 19 February 2014 (has links)
Gli isomeri del CLA (Acido Linoleico Coniugato) potrebbero avere effetti benefici sulla salute in relazione al raggiungimento di un determinato intake, ma, per quanto ci è dato sapere, non esiste letteratura in Italia riguardante l'effettiva quantità di CLA negli alimenti e al relativo intake nell'uomo. Quindi è stata condotta una quantificazione degli isomeri c9,t11 e t10,c12 negli alimenti disponibili sul mercato italiano, seguita da una stima dell'intake di questi isomeri in una coorte della popolazione italiana attraverso un diario alimentare. Lo step successivo del progetto di ricerca, dovuto al livello molto basso di CLA trovato negli alimenti, è stato di investigare i fattori genetici che influenzano il CLA nella carne, per poter aumentare la concentrazione finale di CLA per il consumatore finale. Quindi gli obiettivi del lavoro sono stati: la stima dell'effettivo intake di CLA in Italia attraverso una completa analisi della concentrazione di c9,t11 e t10,c12 nei prodotti lattiero-caseari e carnei comunemente disponibili, e una valutazione dei fattori genetici coinvolti nella sintesi di CLA nella carne. / CLA could exert some healthy properties in relation to a needed daily intake, but, at our knowledge, no literature in Italy is currently available on the effective CLA amount in foods and on the relative intake in humans. Thus a quantification of c9,t11 and t10,c12 CLA isomers in foods available in Italy large retail-scale trade was performed, followed by an estimation of the isomers intake in a cohort of the Italian population by a food diary. Background 6 The following step of the research project, due to the very low concentration of CLA found in foods, investigated genetic factors affecting CLA in meat, in order to enhance its concentration for final consumers. Thus the aims of the present work were to estimate the effective CLA intake in Italy through a complete analisys of c9,t11 and t10,c12 concentrations in dairy and meat products commonly purchasable, and an evaluation on the genetic factors involved in CLA synthesis in meat.
218

Hurdle technologies: microbial inactivation by pulsed electric fields during milk processing.

Rodriguez Gonzalez, Oscar 25 January 2011 (has links)
The application of non-thermal processes pulsed electric fields (PEF) and cross-flow micro-filtration (CFMF) continuous to be studied with the purpose of controlling microorganisms in milk. Trends suggesting increased adoption include the study of Food Safety Objectives as a safety criterion, the promotion of sustainable processing, and the implementation of hurdle strategies. While the advance of gentle processing is counteracted by the risk of enhanced resistance due to microbial stress response, several techniques can be applied to quantitatively assess its impact. The objective of this project was to evaluate the effectiveness of microbial inactivation by PEF and CFMF at various steps of milk processing including shelf-life, its comparison with high temperature short time (HTST) pasteurization, and the quantitative assessment of the cross protection resistance to PEF of Escherichia coli O157:H7. Some differences in mesophilics inactivation were observed in milks (fat contents between 1.1% and 3.1%). Increasing the PEF inlet temperature decreased the treatment time by three or two-fold. The combination of CFMF/PEF yielded similar microbial reductions as CFMF/HTST. Higher inactivation of the coliforms was achieved in homogenized cream (12% fat) compared to non-homogenized. The linear relation between electrical conductivity and nutrient content (fat and solids content) was established. In a parallel study the PEF/CFMF sequence resulted in higher inactivation of mesophilics compared to CFMF/PEF and HTST. The shelf life was acceptable for CFMF/PEF and HTST after 7 days, while enterics and psychrotrophs grew more after PEF/CFMF, thermodurics did after HTST. The growth and stress of Escherichia coli O157:H7 in lactose containing broths was monitored by absorbance and fluorescence expression of stress reporters. Growth was explained using a secondary model, and stress response using mechanistic and probabilistic models. PEF inactivation was evaluated following the Weibull distribution after the cells reached stationary phase or maximum fluorescence expression. Similar resistances were observed within the cells grown in lactose broth at 10, 25 or 40°C, as within stressed cells (starved or cold shocked). Cells grown at 45 °C were more resistant compared to the cells grown in acid, high salt concentration while the ones grown at cold temperatures were the weakest. / Dairy Farmers of Ontario, Natural Sciences and Engineering Research Council.
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LÁCTEOS: ATRIBUTOS VALORIZADOS NA COMPRA, PERFIL DE ÁCIDOS GRAXOS E EFEITOS DO ÁCIDO LINOLÉICO CONJUGADO NO METABOLISMO LIPÍDICO / DAIRY PRODUCTS: ATTRIBUTES VALUED IN PURCHASING, FATTY ACIDS PROFILE AND EFFECTS OF CONJUGATED LINOLEIC ACID ON LIPID METABOLISM

Fuke, Gitane 13 November 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The relationships between nutrition and health have been studied throughout recent years as a result of the growing concern about the population s health. Consumers are increasingly more demanding about the quality of food consumed, inclusively worrying about attributes that go beyond the presence of nutrients and food security, but also concerning about health benefits. The following research aimed to understand which consumer perceptions about the role of animal fats in health and attributes are valued in buying dairy products, determining the levels of conjugated linoleic acid in milk produced in the state of Rio Grande do Sul as well as assessing the antiatherogenic potential of conjugated linoleic acid. In the first chapter of the thesis it was analyzed the behavior of consumers before the purchase of milk, where it is observed that 83% of respondents consume milk and crucial aspects for the consumer is the relationship price and taste. There is a good perspective on buying products with higher levels of conjugated linoleic acid and bringing benefits to consumer s health. Due to the wide and varied range of dairy products, consumer was induced to become more demanding about the quality of the product offered. In Chapter 2, it was determined the fatty acid profile in dairy (milk, cheese, and butter) produced in the state of Rio Grande do Sul and it was found that the composition was similar in both types of milk products produced in Rio Grande do Sul, including as to the presence of conjugated linoleic acid. CLA levels varied according to regions and seasons studied, which showed higher levels in the southern portion of the state and in the spring and winter. The CLA content in milk products produced in southern Brazil have higher values than those reported for dairy products from other countries, including those of temperate climate, which show higher values of this constituent. In chapter, it was assessed the effect of different lipid sources and antiatherogenic potential of conjugated linoleic acid in rabbits fed a diet containing butter, margarine, soybean oil, and synthetic CLA. The results, through hierarchical cluster analysis, showed similar variables in animals that consumed butter and soybean oil + CLA and another group with margarine and soy oil. HDL levels were higher in the treatment that received diet with conjugated linoleic acid and LDL was reduced. The reasons TC:HDL and LDL:HDL significantly increased in the group that consumed margarine. The inclusion of CLA, even at low levels, such as 0.1% in the diet of rabbits exerts inhibitory effect on atherogenesis, since lower levels of LDL cholesterol and higher levels of HDL cholesterol are associated with decreased cardiovascular risk. / As relações entre nutrição e saúde vêm sendo estudadas nos últimos anos, como consequência da preocupação da população com a saúde. Os consumidores estão mais exigentes em relação à qualidade dos alimentos consumidos, preocupando-se com atributos que vão além da presença de nutrientes e segurança alimentar, mas que apresentam também benefícios à saúde. Objetivou-se com o trabalho, entender qual a percepção do consumidor sobre o papel da gordura animal na saúde e os atributos valorizados na compra de produtos lácteos, determinar o perfil de ácidos graxos com ênfase no ácido linoleico conjugado em lácteos produzidos no Rio Grande do Sul e avaliar o potencial antiaterogênico do ácido linoléico conjugado. No primeiro capítulo da tese analisou-se o comportamento dos consumidores frente à compra de lácteos, observa-se que 83% dos entrevistados consomem leite e os aspectos mais importantes são a relação preço e sabor. Existe uma boa perspectiva em relação à compra por produtos com teores mais elevados de ácido linoléico conjugado e que tragam benefícios a saúde do consumidor. Em função da grande e variada oferta de produtos lácteos, induziu o consumidor a tornar-se mais exigente em relação à qualidade do produto oferecido. No capítulo 2 determinou-se o perfil de ácidos graxos em lácteos (leite, queijo e manteiga) produzidos no Rio Grande do Sul e, verificou-se que a composição foi semelhante entre os tipos de produtos lácteos produzidos, inclusive quanto a presença do ácido linoléico conjugado. Os níveis de CLA variaram conforme as regiões e estações climáticas estudadas, onde apresentaram maiores teores na região Sul do Rio Grande do Sul e nas estações da primavera e inverno. O conteúdo em CLA de produtos lácteos produzidos na região Sul do Brasil possuem valores superiores aos relatados para produtos lácteos de outros países, inclusive naqueles de clima temperado, os quais demonstram maiores valores deste constituinte. No capítulo 3 avaliou-se o efeito de diferentes fontes lipídicas e o potencial antiaterogênico do ácido linoléico conjugado em coelhos alimentados com dietas contendo manteiga, margarina, óleo de soja e CLA sintético. Os resultados, através da análise de agrupamento hierárquico, acusaram semelhança nas variáveis dos animais que consumiram manteiga e óleo de soja+CLA e outro grupo pela margarina e óleo de soja. Os níveis de HDL foram maiores no tratamento que recebeu dieta com ácido linoléico conjugado e o LDL foi reduzido. As razões CT:HDL e LDL:HDL apresentaram aumento significativo no grupo que consumiu margarina. A inclusão de CLA, mesmo em níveis baixos, como 0,1% na dieta de coelhos exerce efeito inibitório sobre a aterogênese, pois como observado nesta pesquisa, os menores níveis de colesterol LDL e maiores níveis de colesterol HDL estão associados a diminuição de risco cardiovascular.
220

Desenvolvimento e caracterização de ricota cremosa elaborada com soro de queijo coalho caprino e bovino

Borba, Karla Kaligia Silva 25 January 2013 (has links)
Made available in DSpace on 2015-04-17T14:49:23Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1363192 bytes, checksum: ee62e38789f57cc271f9412e2af6e956 (MD5) Previous issue date: 2013-01-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The ricotta cheese is a smooth flavor, obtained from the coagulation of the whey proteins in cheese with or without the addition of milk. May be fresh, creamy, aged or cured and can be consumed as cream cheese board or in combination with other ingredients in culinary dishes. The preparation of ricotta is an alternative to reusing whey, a co-product of high nutritional value generated in large quantities during processing of the cheese milk to obtain a curd type. In this study was to develop a base of creamy ricotta cheese curd goat whey (40%) and bovine (40%) as main ingredients, with added goat milk (10%) and bovine (10%). The technological characteristics, physicochemical and sensory texture of creamy ricotta were evaluated during refrigerated storage for 14 days. The yield of the process of getting the creamy ricotta was 7.9% and syneresis ranged from 5 to 7% during the study period. During storage, moisture (73.81 to 74.59), the lipid content (8.83 to 9.08) and total solids (25.63 to 26.19) remained stable (p >0,05), while the protein content and ash varied (p <0,05). The instrumental texture profile characterized the creamy ricotta cheese as an easily deformable, inelastic, cohesive, soft texture and delicate, unchanged after 14 days of storage. In the analyzes of instrumental color was observed reduction of yellowing and green tones during cold storage of 14 days. In Quantitative Descriptive Analysis (QDA) flavor and aroma of creamy ricotta goat were described by the panel as soft, wet appearance and soft texture and creamy. O fatty acid profile showed that the fatty acid content of medium and long chain (C14:0, C16:0, C18:0, C18:1n9c and C18:2n6c) was superior to just short chain acid (C6:0) and capric (C:10) decreased (p <0,05) during storage. Among the 14 identified amino acids, threonine, isoleucine, leucine and phenylalanine were increased during the study period, while methionine, lysine and alanine decreased. The results indicate that the use of the mixture of whey curd goat and bovine as the main ingredient of creamy ricotta mixed is viable and not reflected in negative features in the product, suggesting a promising use for reusing the coproduct. / A ricota é um queijo de sabor leve, obtido a partir da coagulação das proteínas do soro de queijos com ou sem a adição de leite. Pode ser fresca, cremosa, maturada ou defumada e pode ser consumida como queijo cremoso de mesa ou em combinação com outros ingredientes em pratos culinários. A elaboração da ricota constitui uma alternativa para o reaproveitamento do soro, co-produto de elevado valor nutricional gerado em grandes quantidades durante o processamento do leite para obtenção de queijo tipo coalho. No presente estudo foi elaborada uma ricota cremosa a base de soros de queijo coalho caprino (40%) e bovino (40%) como ingredientes principais, com adição de leite integral de cabra (10%) e de vaca (10%). As características tecnológicas, físico-químicas, de textura e sensoriais da ricota cremosa foram avaliadas durante armazenamento refrigerado por 14 dias. O rendimento do processo de obtenção da ricota cremosa foi de 7,9% e a sinerese variou de 5 a 7% no período estudado. Durante o armazenamento, a umidade (73,81-74,59), o teor de lipídios (8,83-9,08) e extrato seco total (25,63-26,19) permaneceram estáveis, (p>0,05), enquanto os teores de proteínas e cinzas variaram (p<0,05). O perfil de textura instrumental caracterizou a ricota cremosa como um queijo facilmente deformável, pouco elástico, coeso, de textura macia e delicada, sem alterações após 14 dias de armazenamento. Nas análises de cor instrumental foi observado amarelecimento e redução dos tons de verde durante o armazenamento refrigerado de 14 dias. O sabor e aroma caprino da ricota cremosa foram descritos pelo painel da Análise Descritiva Quantitativa (ADQ) como suaves, a aparência como molhada e a textura como macia e cremosa. O perfil de ácidos graxos mostrou que o conteúdo de ácidos graxos de cadeia média e longa (C14:0; C16:0; C18:0; C18:1n9c e C18:2n6c) foi superior ao de cadeia curta (C6) e apenas o ácido cáprico (C:10) diminuiu (p<0,05) durante o armazenamento. Dentre os 14 aminoácidos livres identificados, treonina, isoleucina, leucina e fenilalanina tiveram aumento nos teores no período estudado, enquanto metionina, lisina e alanina diminuíram. Os resultados indicam que o uso da mistura de soro de queijo coalho caprino e bovino como ingrediente principal de ricota cremosa mista é viável e não repercute em características negativas no produto, sugerindo um emprego promissor para o reaproveitamento do co-produto.

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