The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
F. Xavier Malcata - One of the best experts on this subject based on the ideXlab platform.
-
Role of dominant microflora of Picante cheese on proteolysis and lipolysis
International Dairy Journal, 1999Co-Authors: A. Cristina Freitas, Ana I.e. Pintado, Manuela Pintado, F. Xavier MalcataAbstract:Abstract Four species of bacteria ( Enterococcus faecium and E. faecalis, Lactobacillus plantarum and Lb. paracasei ) and three species of yeasts ( Debaryomyces hansenii, Yarrowia lipolytica and Cryptococcus laurentii ) isolated from Picante cheese were assayed for proteolytic and lipolytic activities. The Milk Type (caprine or ovine), the ripening time (0–65 d) and the concentration of NaCl (0–14% (w/v)) have been studied in terms of their effects upon in vitro curdled Milk. Proteolytic and peptidolytic activities were demonstrated to be high for Y. lipolytica , and at much lower levels for the other strains. Milk Type, ripening time and content of NaCl appeared to be statistically significant processing factors in terms of proteolysis. Clear lipolytic activity was detected for Y. lipolytica , but release of free fatty acids to lesser extents was observed for the other strains under study. Ripening time was statistically significant for lipolysis but Milk Type was not. Lipolytic activities were strongly affected by NaCl content and the extent of fat hydrolysis was affected by the increase of NaCl from 0 to 7% (w/v) more than by change from 7 to 14% (w/v). In view of the experimental results, a mixed-strain starter for Picante cheese including Lb. plantarum, E. faecium (or E. faecalis ) and D. hansenii (and/or Y. lipolytica ) is of potential interest.
-
Lipolysis in Picante cheese: Influence of Milk Type and ripening time on free fatty acid profile
Le Lait, 1998Co-Authors: Ana C. Freitas, F. Xavier MalcataAbstract:Changes in the profile of the major free fatty acids (FFA) were assayed by HPLC up to 180 days of ripening in batches of cheeses manufactured with different proportions of ewe's and goat's Milks. Evolution of lipolysis was also monitored by ethanolic titration, and good linear correlations were found between the two methods. For every batch of cheese, concentrations of all FFA exhibited continuous increases throughout the ripening period; levels of total FFA by 180 days of ripening ranged from 50.3 to 62.3 g / kg of fat depending on the cheeseMilk composition; C1o, C16, C18, and C18:1, were the most concentrated FFA throughout the whole ripening period. Values for the short chain FFA (C4, C6, and C8) ranged from 2.8 to 4.5 g / kg of fat; such concentrations, which were not significantly different between batches with different proportions of ewe's and goat's Milks, contributed considerably to the characteristic piquant flavor of Picante cheese
-
Influence of Milk Type, coagulant, salting procedure and ripening time on the final characteristics of Picante cheese.
International Dairy Journal, 1996Co-Authors: A. Cristina Freitas, F. Xavier MalcataAbstract:Abstract Picante da Beira Baixa cheese is a hard, spicy, salty traditional cheese with a minimum ripening time of 120 d that is manufactured in Portugal at a farm level only. The purpose of this work was to study the influence of several manufacturing conditions (viz. mixture of ovine and caprine Milks, source of coagulant, level of NaCl addition, and duration of ripening period) on the final characteristics of this cheese following a (replicated) factorial design. Milk Type proved to be a statistically significant technological parameter in terms of numbers of viable microorganisms of various genera and the extent of proteolysis, probably as a consequence of higher initial contamination of caprine Milk. The Type of coagulant had a major effect on proteolysis: values of water-soluble nitrogen for cheeses coagulated with animal rennet were in general lower than those for cheeses coagulated with plant rennet, but much smaller differences were detected between values of non-protein nitrogen: and breakdown of αs- and β-caseins was more extensive in Picante cheeses manufactured with plant rennet. The level of NaCl was a statistically significant parameter for all microbiological, physicochemical and chemical characteristics measured, an observation that is probably due to its capacity to reduce water activity. Ripening time did not have a significant effect on the numbers of viable staphylococci.
Gilles Feron - One of the best experts on this subject based on the ideXlab platform.
-
Salt release monitoring with specific sensors in "in vitro" oral and digestive environments from soft cheeses
Talanta, 2012Co-Authors: Larisa Lvova, Patrick Mielle, Christian Salles, Sylvain Denis, C. Vergoignan, Aurélien Barra, Corrado Di Natale, Roberto Paolesse, Pierre Temple-boyer, Gilles FeronAbstract:The objective of the present work is to demonstrate the interest and the feasibility of the measurement of NaCl concentrations in soft cheeses and in particular an in vitro digestion process by the use of chemical sensors. The analyzed matrices were the commercial Italian mozzarella cheeses and domestic cheese base models. The classification of mozzarellas was performed according to their salinity, while the breakdown of cheese base models has been followed both at initial steps of digestion in artificial mouth dispositive mimicking the oral sphere and in a gut-imitating digester (TIM-1). During the breakdown of soft cheese in the digester, the estimated values for Na+ concentration using mono-Na-ISEs showed correlation coefficients values about 0.907 and 0.832 compared to Ionic Chromatography (IC) reference values, with an important relative error (about 30-40%). The use of ISE array system combining several electrodes, in particular electrodes showing more selectivity to Cl- and Na+ ions, showed the best results for Na+ concentration estimation, with good correlations both in calibration (R=0.962) and in validation (R=0.952) steps. For cheese digestion in the artificial mouth, good correlations for Na+ concentration were observed using single Na-ISE compared to IC with coefficients ranking between 0.93 and 0.96 for both the calibration and validation steps. Moreover, a fair correlation between chloride ions measured with CI-ISE2 and Na+ (R=0.96) was found. The best results were obtained with the use of ISEs array combining, in particular, Cl- and Na+ detections. The salinity of commercial mozzarella cheese samples, as far as originally utilized Milk Type (cow or buffalo), were also satisfactory determined with developed ISE array.
-
An Application of Specific Sensors For The Monitoring of NaCl in Soft Cheeses
2011Co-Authors: Larisa Lvova, Patrick Mielle, Christian Salles, Sylvain Denis, C. Vergoignan, Aurélien Barra, Corrado Di Natale, Roberto Paolesse, Pierre Temple-boyer, Gilles FeronAbstract:The commercial sensors and protoType ISEs array (Ion Selective Electrodes array) were utilized for NaCl concentration measurements in soft cheeses, in particular in vitro gut process and in commercial Italian mozzarella cheeses. The values obtained from the sensors were compared with HPLC analysis. The results showed the feasibility of the ISE array application to monitor NaCl in soft cheese during the breakdown in the digester. The best results were obtained with the use of ISEs array combining, in particular, Cl− and Na+ detections. The salinity of commercial mozzarella cheese samples and the originally utilized Milk Type (cow or buffalo) were also satisfactory determined with the developed ISE array.
A. Cristina Freitas - One of the best experts on this subject based on the ideXlab platform.
-
Role of dominant microflora of Picante cheese on proteolysis and lipolysis
International Dairy Journal, 1999Co-Authors: A. Cristina Freitas, Ana I.e. Pintado, Manuela Pintado, F. Xavier MalcataAbstract:Abstract Four species of bacteria ( Enterococcus faecium and E. faecalis, Lactobacillus plantarum and Lb. paracasei ) and three species of yeasts ( Debaryomyces hansenii, Yarrowia lipolytica and Cryptococcus laurentii ) isolated from Picante cheese were assayed for proteolytic and lipolytic activities. The Milk Type (caprine or ovine), the ripening time (0–65 d) and the concentration of NaCl (0–14% (w/v)) have been studied in terms of their effects upon in vitro curdled Milk. Proteolytic and peptidolytic activities were demonstrated to be high for Y. lipolytica , and at much lower levels for the other strains. Milk Type, ripening time and content of NaCl appeared to be statistically significant processing factors in terms of proteolysis. Clear lipolytic activity was detected for Y. lipolytica , but release of free fatty acids to lesser extents was observed for the other strains under study. Ripening time was statistically significant for lipolysis but Milk Type was not. Lipolytic activities were strongly affected by NaCl content and the extent of fat hydrolysis was affected by the increase of NaCl from 0 to 7% (w/v) more than by change from 7 to 14% (w/v). In view of the experimental results, a mixed-strain starter for Picante cheese including Lb. plantarum, E. faecium (or E. faecalis ) and D. hansenii (and/or Y. lipolytica ) is of potential interest.
-
Influence of Milk Type, coagulant, salting procedure and ripening time on the final characteristics of Picante cheese.
International Dairy Journal, 1996Co-Authors: A. Cristina Freitas, F. Xavier MalcataAbstract:Abstract Picante da Beira Baixa cheese is a hard, spicy, salty traditional cheese with a minimum ripening time of 120 d that is manufactured in Portugal at a farm level only. The purpose of this work was to study the influence of several manufacturing conditions (viz. mixture of ovine and caprine Milks, source of coagulant, level of NaCl addition, and duration of ripening period) on the final characteristics of this cheese following a (replicated) factorial design. Milk Type proved to be a statistically significant technological parameter in terms of numbers of viable microorganisms of various genera and the extent of proteolysis, probably as a consequence of higher initial contamination of caprine Milk. The Type of coagulant had a major effect on proteolysis: values of water-soluble nitrogen for cheeses coagulated with animal rennet were in general lower than those for cheeses coagulated with plant rennet, but much smaller differences were detected between values of non-protein nitrogen: and breakdown of αs- and β-caseins was more extensive in Picante cheeses manufactured with plant rennet. The level of NaCl was a statistically significant parameter for all microbiological, physicochemical and chemical characteristics measured, an observation that is probably due to its capacity to reduce water activity. Ripening time did not have a significant effect on the numbers of viable staphylococci.
Mark D. Deboer - One of the best experts on this subject based on the ideXlab platform.
-
Longitudinal evaluation of Milk Type consumed and weight status in preschoolers
Archives of disease in childhood, 2013Co-Authors: Rebecca J. Scharf, Ryan T. Demmer, Mark D. DeboerAbstract:Objective To evaluate relationships between Type of Milk consumed and weight status among preschool children. Design Longitudinal cohort study. Setting The Early Childhood Longitudinal Study, Birth Cohort, a representative sample of US children. Participants 10 700 US children examined at age 2 and 4 years. Main outcome measures Body mass index (BMI) z score and overweight/obese status as a function of Milk Type intake. Results The majority of children drank whole or 2% Milk (87% at 2 years, 79.3% at 4 years). Across racial/ethnic and socio-economic status subgroups, 1%/skim Milk drinkers had higher BMI z scores than 2%/whole Milk drinkers. In multivariable analyses, increasing fat content in the Type of Milk consumed was inversely associated with BMI z score (p Conclusions Consumption of 1%/skim Milk is more common among overweight/obese preschoolers, potentially reflecting the choice of parents to give overweight/obese children low-fat Milk to drink. Nevertheless, 1%/skim Milk does not appear to restrain body weight gain between 2 and 4 years of age in this age range, emphasising a need for weight-targeted recommendations with a stronger evidence base.
Maryanne Drake - One of the best experts on this subject based on the ideXlab platform.
-
The influence of automatic associations on preference for Milk Type.
Journal of dairy science, 2020Co-Authors: W.s. Harwood, Maryanne DrakeAbstract:ABSTRACT In recent decades, organic Milk has been an exception to the trend of decreased fluid Milk consumption in the United States. However, the reasons behind consumer preference for organic Milk over conventional and other Milk Types are ill-defined. The objective of this study was to use an implicit association test (IAT) and primed and unprimed preference testing to determine if fluid Milk consumer preferences for Milk Types are influenced by implicit biases and, if so, to define these biases within the context of the consumer sensory experience. Self-reported fluid Milk consumers (n = 473) participated in online IAT exercises where pairwise comparisons of Milk Types (conventional, organic, local, pasture-raised) were measured on both positive and negative dimensions related to cow-welfare, sustainability, health, trust, safety, and quality. Latency times from IAT responses were subsequently transformed into standardized D-scores to categorize bias effect sizes. Additionally, fluid Milk consumers (n = 174) participated in preference tests that compared commercial Milks representing different Milk Types through presentations where Milk Type was shown (primed) or hidden (unprimed). Following preference tests, consumers were asked to explain their preferred sample using check-all-that-apply tasks. Analysis of IAT results showed that conventional Milk was more associated with negative dimension descriptors compared with organic, local, and pasture-raised Milks. Additionally, a positive bias in favor of organic Milk was expressed when compared with pasture-raised Milk offerings; however, no differences were found in pairwise comparisons of other nonconventional Milk Type pairings, suggesting that consumers may conflate these designations. Blinded preference testing showed that Milk preferences were largely dictated by flavor, with consumers differentiating Milk Types based upon flavors related to packaging, pasteurization method, and feeding systems. In primed evaluations, consumers generally expressed preferences that aligned with their explicit beliefs, and flavor considerations appeared to be a secondary differentiator of preference. Based on these results, conventional Milk is associated with negative implicit beliefs related to production and product quality more often than other Milk Types, which was reflected in IAT evaluations and primed preference tests. However, the blinded tastings suggested that conventional Milk was preferred, or competitive with, other Milk Types based on flavor alone. Findings from this study suggest consumer differentiation and preference of Milks is significantly affected by perceptions and beliefs related to Milk Type. In particular, conventional Milk was associated with relatively few unique belief descriptions, indicating strict utilitarian consumer categorization. Organic and local Milks were comparatively associated with greater care for nutrition, sustainability, animal welfare, and local farm support. These results demonstrate a need for greater education related to conventional Milk offerings to dispel factors influencing negative implicit bias. Furthermore, improving product narrative via label information and alignment with locality and regionality were identified as possible opportunities for improving consumer sentiments related to conventional Milk. A more thorough understanding of these attributes may reinforce stated beliefs more effectively and stave off consumer losses to plant-based alternatives that fulfill similar beliefs.
-
Validation of fluid Milk consumer segments using qualitative multivariate analysis.
Journal of dairy science, 2020Co-Authors: W.s. Harwood, Maryanne DrakeAbstract:ABSTRACT Consumption of fluid Milk in the United States has declined in recent years. To increase appeal and meet ever-changing consumer demands, several product features have been introduced to the fluid Milk market. As such, it is imperative to assess consumer sentiments from both quantitative and qualitative perspectives to better understand the effect of various product offerings. The objectives of this study were to identify fluid Milk consumer segments that were characterized by preference for specific product features and to verify those sentiments using qualitative multivariate analysis (QMA). An adaptive choice-based conjoint survey (n = 719) was designed to explore consumer desires regarding the fat content, package Type, shelf life, label claims, and prices of commercial Milks. Part-worth utilities from the conjoint task were subsequently clustered, revealing 4 unique consumer segments. Representative consumers from each cluster (n = 18 total) were selected to participate in a 4-wk QMA study, consisting of a home-usage test followed by focus groups and projective mapping. Nine commercial Milks representing various pasteurization methods, label claims, and packaging Types were used within the study. When analyzed by segment, significant differences in conjoint utilities for specific product features were identified. Overall, price was the largest differentiator of segments, followed by fat content, shelf life, and Milk designation. Several of the segmental differences were confirmed in the QMA study, with sentiments regarding price and Milk Type (i.e., conventional, organic, local) consistent between conjoint survey and QMA for each consumer group. Within the projective mapping exercise, intrinsic sensory properties, price, and quality perception were the primary differentiators for fluid Milks. Comments from QMA journal entries and focus groups revealed that consumer segments with preferences for nonconventional Milk Types were primarily motivated by the belief that organic, local, or pasture-raised Milks were superior in sensory quality and congruent with personal values. Overall, QMA was an effective means for verifying conjoint-derived consumer groups and provided a contextual support for conjoint insights. Joint conclusions drawn from the components of this study may serve to guide marketing campaigns and new product development for fluid Milk processors.
-
APPLICATION OF ETHNOGRAPHY AND CONJOINT ANALYSIS TO DETERMINE KEY CONSUMER ATTRIBUTES FOR LATTE‐STYLE COFFEE BEVERAGES
Journal of Sensory Studies, 2012Co-Authors: S.m. Jervis, K. Lopetcharat, Maryanne DrakeAbstract:The objective of this study was to examine and compare ethnography and conjoint analysis to identify the factors that influence choice of latte-style coffee beverages. Ethnographical data were collected at four of the top producers of latte-style beverages. Attributes measured by the conjoint survey included location of purchase, Milk Type, fat content, sweetener Type and additional flavor. Consumer responses (n = 721) from the conjoint survey showed that the most important attributes in determining latte beverage purchase intent were location and Milk Type, followed by fat content, sweetener and additional flavor. Segmentation of respondents based upon patterns in utility scores showed three distinct groups. Segment 1 (n = 185) called the “indulgents” was influenced by Milk Type and sweetener Type. Segment 2 (n = 200), “location consumers,” was influenced by a coffee house. Segment 3 (n = 336), “health conscious,” was calorie and health conscious. Ethnographical observations identified and described the consumer segments based upon patterns of behaviors and were in alignment with consumer responses to survey questions. Ethnography coupled with choice-based conjoint provided a robust technique for understanding consumer choices of latte-style coffee beverages. PRACTICAL APPLICATIONS Choice-based conjoint analysis is a quantitative survey technique designed to collect large amounts of information from consumers in a realistic scenario format. Ethnography is a qualitative research tool that provides insight to consumer consumption and purchase behaviors that may not be readily acquired by quantitative approaches. These behaviors can be just as important as the product attributes themselves in determining liking and purchase. Coffee companies will be able to utilize the results to better target the attributes that are driving consumer choice.