Fermentation of whey-derived matrices by Kluyveromyces marxianus: alcoholic beverage development from whey and fruit juice mixes.

This research paper addresses the hypotheses that Kluyveromyces marxianus can be cultured with good alcohol production on different whey-derived matrices, and that the fermented product can be used in order to develop alcoholic beverages with acceptable sensory characteristics by mixtures with yeast-fermented fruit-based matrices. Growth and fermentative characteristics of Kluyveromyces marxianus LFIQK1 in different whey-derived matrices were explored by culturing (24 h, 30°C) on reconstituted whey, demineralized whey, heat-treated whey and milk permeate media. High lactose consumption, ethanol production and yield were observed. Reconstituted whey matrix was selected for mixing with orange or strawberry juices fermented using Saccharomyces cerevisiae to obtain alcoholic beverages (W-OR and W-ST, respectively). Consumer evaluation of beverages was performed using acceptability and Check-All-That-Apply (CATA) questions. Good acceptance was observed, significantly higher for W-ST than for W-OR. CATA questions gave information about organoleptic characteristics of beverages. Penalty analysis showed W-R and W-ST were positively associated with smooth/refreshing and fruity/natural, respectively. Liking was represented, accordingly with penalty analysis, by natural/refreshing. A novel alternative for utilization of whey and whey-related matrices by alcoholic beverages production with natural ingredients is presented.

Squalene encapsulation by emulsification and freeze-drying process: Effects on bread fortification.

In the present work, squalene (SQ) was encapsulated by a conventional emulsion method using egg white protein nanoparticles (EWPn) as a high molecular weight surfactant, followed by a freeze-drying process to obtain an SQ powder ingredient. EWPn was produced by heat treatment at 85°C, 10 min, and pH 10.5. EWPn showed higher emulsifying activity regarding native egg white protein (EWP), highlighting their potential to be used for the SQ encapsulation by an emulsification process. First, we explored the encapsulation conditions using pure corn oil as an SQ carrier. Conditions were oil fraction (0.1-0.2), protein amount (2-5 wt.%), homogenization pressure (100 and 200 bar), and maltodextrin amount (10-20 wt.%). At 0.15 oil fraction, 5 wt.%. protein concentration, 200 bar homogenization pressure, and 20% maltodextrin, the highest encapsulation efficiency (EE) was reached. Then, according to these conditions, SQ was encapsulated to obtain a freeze-dried powder ingredient for bread formulation. The total and free oil of SQ freeze-dried powder were 24.4% ± 0.6% and 2.6% ± 0.1%, respectively, resulting in an EE value of 89.5% ± 0.5%. The physical, textural, and sensory properties of functional bread were not affected by the addition of 5.0% SQ freeze-dried powder. Finally, the bread loaves showed higher SQ stability than the one formulated with unencapsulated SQ. Hence, the encapsulation system developed was suitable for obtaining functional bread based on SQ fortification.

Applicability of the probiotic Lactiplantibacillus plantarum BFL as an adjunct culture in a dry fermented sausage.

The addition of probiotic bacteria to a meat batter allows the development of functional fermented sausages. The aim of this work was to study the effect of microencapsulated Lactiplantibacillus plantarum BFL (EP) and as free cells (FP) on microbiological, physicochemical, and sensory parameters of fermented sausages during the drying stage and on the product ready for consumption. The microencapsulation of L. plantarum BFL did not improve its viability during the drying stage. In addition, sausages inoculated with L. plantarum BFL (FP and EP) caused lower residual nitrites values, pH values and Escherichia coli counts than the Control (C). However, only the presence of free cells of L. plantarum BFL (FP) caused a decrease in the Enterobacteriaceae and mannitol salt-positive Staphylococcus counts. In the sensory analysis, no significant differences were found in the acceptability of the different sausages. However, the acidity in probiotic sausages (FP and EP) was an attribute that consumers highlighted. The probiotic L. plantarum BFL could adapt and survive at high doses in the matrix of an industrial fermented sausage. Therefore, its use could represent a strategy both for biocontrol of pathogens and for the development of functional meat products.

More than words! A narrative review of the use of the projective technique of word association in the studies of food consumer behavior: Methodological and theoretical implications.

Word association (WA) is a projective and powerful technique that consists of the spontaneous generation of words from specific stimuli. This technique is used in sociology and psychology studies; however, in the Consumer and Food Science area has gained importance since it allows to explore beliefs, expectations, or attitudes in the context of food consumption behavior. The aim of this work is to present a current status on the use of this technique in the studies of food consumption behavior. A narrative review of the literature was carried out with articles published in four databases: ScienceDirect, Wiley Online Library, Emerald Insight, and Taylor & Francis. Seventy-four articles that show the use of the WA technique in different cultures were selected. WA technique has been applied in different countries, however, it has been primarily used in Latin America. WA has been applied mainly to decipher consumers' perceptions towards different aspects of food, although some works show that WA serves to understand beliefs, expectations, impressions, attitudes, and even to conceptualize different categories of food from the language of consumers. Some theoretical and methodological implications are discussed regarding the use and application of this projective technique.

Cross-cultural representations of gastronomy among consumers in two Latin American countries.

Gastronomy is one of the cultural emblems of each region and represents the way each society feeds. The aim of this article was to understand the cross-cultural representations of the concept of gastronomy among consumers in Argentina (ARG) and Mexico (MEX). A survey in which 479 consumers of both countries were recruited (ARG = 249, MEX = 230), who had to complete a word association task, was designed. Words were grouped into categories and the differences in the frequency of mention were analyzed with the Chi Square test. Furthermore, results were analyzed to identify the central core and the peripheral areas of the social representations. Cognitive Salience Index (CSI) was calculated to determine the most important representations. The representations of the gastronomy concept in both countries indicate a strong link to culture, food, pleasure by eating and sensory characteristics of foods and dishes. However, the field of representation, the hierarchy of representations and the cognitive and attitudinal importance were different among Mexican and Argentine consumers, which suggests that gastronomy promotion campaigns for both countries should be oriented according to consumers' perceptions.

Identifying consumers' profile and factors associated with the valorization of pulque: A traditional fermented beverage in Central Mexico.

The aims of this work were to (i) identify the consumers' profile of pulque through their consumption frequency and their sensory perception of this beverage and (ii) identify the factors that contribute to the valorization of pulque among Mexican consumers. A survey was designed and conducted with 221 consumers in pulque-selling locations (pulquerías) in a place of Central Mexico. Consumers were characterized according to their consumption frequency. Factors associated with the valorization of pulque were identified through Binary Logistic Regression model. Two types of consumers were identified: Frequent Consumers and Not Frequent Consumers. Both groups were comprised mostly of men, including students with medium to high levels of education. However, the first group showed more traditional and conservative behavior patterns since there was a higher proportion of consumers with a low educational level (p < 0.05) and they had more years of consumption, spend more time in the selling locations, and preferred "natural pulque." The second group of consumers was comprised mostly (p < 0.05) of women, including students with a high educational level who prefer "cured pulque." In this sense, our results showed that gender and time spent in the pulquerías together with sensory, cultural, and functional characteristics associated with the beverage influence its valorization among consumers. These results can help both producers and marketers to classify segments of consumers according to their preferences and consumption patterns in order to revalorize the pulque market. Finally, it is necessary to highlight that young consumers with high educational level show interest in this beverage, since for years its consumption has been associated with low-income populations.

Evaluation of autochthonous cultures to improve the cheese flavor: A case study in hard cheese model.

The characterization of autochthonous cultures based on their contribution to cheese flavor is an additional selection criterion for their use in cheese making. The objective of the present work was to assess the ability of three strains of mesophilic lactobacilli: Lactobacillus casei 72 (Lc72), L. paracasei 90 (Lp90), and L. plantarum 91 (Lp91), one strain of thermophilic lactobacillus: L. helveticus 209 (Lh209), and the thermophilic-mesophilic combinations, to grow and produce aroma compounds in a hard cheese model. Microbiological counts, pH, and the profiles of carbohydrates, organic acids, and volatile compounds were analyzed during incubation for 14 days at 37 ℃. The population of mesophilic lactobacilli reached levels around 8.0 log CFU ml-1 at three days, but then decreased until ∼7.0 log CFU ml-1 toward 14 days. Thermophilic lactobacillus population reached and maintained levels around 7.7 log CFU ml-1 during incubation. Carbohydrates were absent in the hard cheese model, and so no change in the pH values and in the levels of lactic acid was detected. Mesophilic lactobacilli, inoculated individually or in association with Lh209, metabolized the citric acid and produced ethanoic acid. The profiles of volatile compounds of mesophilic lactobacilli (characterized mainly by butan-2-one, 3-hydroxybutan-2-one, 3-methylbutan-1-ol, hexan-1-ol, 2-phenylethanol, and ethanoic acid) were different from the profile of thermophilic lactobacillus Lh209 (characterized mainly by heptan-2-one, ethyl acetate, isoamyl hexanoate, pentan-1-ol, decanoic acid, and 2- and 3-methylbutanal). Cooperative effects in the production of compounds related to cheese flavor, such as 3-hydroxybutan-2-one, ethyl butanoate, ethanol, pentan-2-ol, hexan-1-ol, benzeneacetaldehyde, 2-phenylethanol, and heptanoic acid, were largely evidenced between Lh209 and Lp91; in a lesser extent, cooperative effects were also found for Lh209+Lp90 for the following compounds: 3-hydroxybutan-2-one, isoamyl acetate, and ethanoic acid. Of the mesophilic lactobacilli strains evaluated, Lp91 and Lp90 would be interesting candidates for its use as adjunct cultures in hard cheeses to improve and diversify the flavor.

Time orientation and risk perception moderate the influence of sodium warnings on food choice: Implications for the design of communication campaigns.

The inclusion of sodium warnings on food packages has been proposed as a means to encourage population to reduce sodium intake. However, consumers who focus on today rather than tomorrow or consumers who downplay or underestimate risks might pay little attention to warnings. The aim of the present study was to explore whether time orientation and perceived risk of sodium consumption may moderate the influence of sodium warnings on food choices. An online study involving 498 Uruguayan participants was carried out. Participants evaluated pairs of bread packages differing in three 2-level variables (sodium warning, type of bread and brand) and were asked to indicate the one they would choose if they were in a supermarket. Then, they answered a scale on 'consideration of future consequences' adapted to eating habits, and responded to statements measuring perceived risk of sodium consumption. Results revealed that sodium warnings had a significant effect on participants' choices. However, the efficacy of warnings was moderated by time orientation and risk perception. A focus on immediate consequences and thinking that the risk associated with sodium consumption can be compensated, decreased the efficacy of the sodium warning. These results provide experimental evidence of the potential of warnings to discourage consumption of products with high sodium content and suggest that communication campaigns accompanying the introduction of warnings should promote a future-oriented vision on eating habits, raise risk awareness and stress that the risks are not easily compensated.

In vivo study of the immunomodulatory capacity and the impact of probiotic strains on physicochemical and sensory characteristics: Case of pasta filata soft cheeses.

Nowadays, there is a great interest of food industries on the development of innovative dairy products containing probiotic bacteria. Beyond yoghurt, cheeses could be a suitable matrix for the incorporation of probiotics. This work aimed to study the impact of the addition of two probiotic lactobacilli (L. rhamnosus GG and L. acidophilus LA5), either individually or combined, on the physicochemical and sensory characteristics of pasta filata soft cheeses and to evaluate the immunomodulating capacity of the product using an in vivo model. Four cheese types were produced: CC (control cheese); L-C (added with L. acidophilus LA5); GG-C (added with L. rhamnosus GG) and GGL-C (added with both probiotics). No differences in gross composition were found. An increase in secondary proteolysis was observed in GGL-C cheeses which correlated with a greater bitter and aftertaste. On the contrary, the L-C cheese received the highest overall quality score. The translocation assay was negative. Moreover, the three experimental cheeses were able to modulate the immune system of mice by reducing the secretion of pro-inflammatory cytokines in the intestine, downregulating the levels of interleukin (IL)-10 and increasing the secretion of Secretory Immunoglobulin A (S-IgA). No synergistic effect was detected when both probiotics were added.

Sensory product characterisations based on check-all-that-apply questions: Further insights on how the static (CATA) and dynamic (TCATA) approaches perform.

Check-all-that-apply (CATA) questions have become one of the most popular methods for sensory characterisation with consumers. Temporal CATA (TCATA) is an extension of the former that takes into account the dynamic nature of sensory perception. The aim of the present work was to expand the methodological comparison of CATA and TCATA questions, considering the characterisation of solid products that undergo substantial oral processing when consumed. Five studies involving a total of 731 consumers were conducted with different product categories: dried apricots, peas, cheese, bread and milk chocolate. A between-subjects experimental design was used to compare the static and dynamic versions of CATA questions. For comparison purposes, TCATA data were analysed as CATA by collapsing the data into four fixed time intervals (quarters). The four quarters of TCATA were compared to results from CATA considering the frequency of use of the terms, sample discrimination, and product configurations. The temporal aspect of TCATA did not largely modify the average citation proportion of terms or the maximum citation proportion for individual terms. Significant differences among samples were established for most of the terms in both CATA and TCATA evaluations, albeit some subtle differences between the two methods were found. These differences were dependent on the product category and the specific sensory characteristics that were relevant for describing the focal samples. The largest differences were found for Study 5 (milk chocolate), for which TCATA identified a few additional insights on the evolution of similarities and differences among samples. However, in most cases general findings were virtually identical for both methodological approaches. In light of these results, the extra effort of using a dynamic sensory characterisation method compared to a static one, may, in many instances, not be warranted.

Understanding consumers' perception and consumption motives towards amaranth in Mexico using the Pierre Bourdieu's theoretical concept of Habitus.

The aim of this work was to study, from a sociological approach, the perception and consumption motives of amaranth in Mexico using Pierre Bourdieu's theoretical concept of Habitus. A survey was conducted in Mexico City with 610 consumers. Socioeconomic information of gender, age, cultural and economic capitals as internal dispositions that generate social differentiation processes were collected. Consumers' perception was identified using an open question through which participants mentioned why they consider the consumption of amaranth to be good. Words, phrases or comments mentioned were grouped into categories through the lemmatization process, and analysed with Global, Per-Cell Chi Square tests and Correspondence Analysis. A Food Choice Questionnaire was used to identify consumption motives of amaranth through Exploratory Factor Analysis and Cluster analysis to identify groups of consumers according to their consumption motives. Results indicated eight categories that reflect consumers' perception towards amaranth (Health and well-being, Functionality, Mitigate hunger, Nutritional components, Nutrition, Feeding, Traditional food and Energy), which converge upon traditionality and functionality. Consumption motives were differentiated into "food as form" and "food as function". Cluster analysis showed distinction in the perception and taste for amaranth. Gender, age, cultural capital and willingness to buy novel food products with added amaranth are markers that reflect internal dispositions of consumers according to their class adscription, and therefore represent their Habitus.

Effect of storage temperature on the chemical, microbiological, and sensory characteristics of pasta filata soft cheese containing probiotic lactobacilli.

The aim of this study was to manufacture pasta filata cheeses added with two probiotic lactobacilli: Lactobacillus rhamnosus GG and Lactobacillus acidophilus LA5, either individually or combined, and to evaluate the effect of the storage temperature (4 and 12 °C) on their chemical, microbiological, and sensorial characteristics. Three cheese types were made: (i) G: containing L. rhamnosus GG, (ii) L: containing L. acidophilus LA5, and (iii) GL: containing both probiotic strains. Gross composition, pH, microbiological, and sensory characteristics were determined. No differences in gross composition were found among them. pH values remained above 5.2 in cheeses stored at 4 °C. However, a postacidification was observed in cheeses ripened at 12 °C. L. acidophilus LA5 was not able to grow, while L. rhamnosus GG grew 1.5 log10 CFU/g in G and GL cheeses stored at 12 °C, reducing the pH from day 8 onwards. These results emphasize the importance of the storage temperature since the good characteristics of probiotic cheeses are kept if the cold-chain is respected. Thus, the selection of probiotics, together with the food matrix and the starter, should be carefully evaluated.

Influence of the culture preparation and the addition of an adjunct culture on the ripening profiles of hard cheese.

The aim of this work was to evaluate the impact of two factors on the ripening profiles of hard cooked cheeses: (F1) the growth medium for the primary and adjunct cultures, constituted by autochthonous strains: Lactobacillus helveticus 209 (Lh209) and Lactobacillus paracasei 90 (Lp90), respectively, and (F2) the addition of L. paracasei Lp90 as adjunct culture. Four types of cheeses were made: W and M cheeses in which only Lh209 was added after its growth in whey and MRS, respectively; Wa and Ma cheeses in which both strains (Lh209 and Lp90) were added after their growth in whey and MRS, respectively. Physicochemical and microbial composition, proteolysis and profiles of organic acids and volatile compounds were analyzed. According to the methodology of the cultures preparation, W and Wa cheeses showed a higher level of secondary proteolysis and lower level of primary proteolysis (P < 0·05), lower content of citric and acetic acids and higher amount of propionic acid (P < 0·05), in comparison with M and Ma cheeses. The incorporation of Lp90 increased the secondary proteolysis (P < 0·05), decreased the citric acid (P < 0·05), and increased the propionic acid only when was added after their growth in whey (P < 0·05). Both factors significantly modified the percentages of the volatile compounds grouped in chemical families; in addition, for the half of the compounds detected, significant differences were found. Based on the obtained results, the use of Lp90 as an adjunct in hard cooked cheeses, and the preincubation of the cultures in whey are strategies to accelerate the cheese ripening and to enhance the production of some characteristic compounds of this type of cheeses, such as propan-2-one, hexan-2-one, 2- and 3-methyl butanal, heptan-2-ol, acetic and 3-methylbutanoic acids and 3-hydroxy butan-2-one.

Characterization of volatile compounds produced by Lactobacillus helveticus strains in a hard cheese model.

Starter cultures of Lactobacillus helveticus used in hard cooked cheeses play an important role in flavor development. In this work, we studied the capacity of three strains of L. helveticus, two autochthonous (Lh138 and Lh209) and one commercial (LhB02), to grow and to produce volatile compounds in a hard cheese extract. Bacterial counts, pH, profiles of organic acids, carbohydrates, and volatile compounds were analyzed during incubation of extracts for 14 days at 37 ℃. Lactobacilli populations were maintained at 106 CFU ml-1 for Lh138, while decreases of approx. 2 log orders were found for LhB02 and Lh209. Both Lh209 and LhB02 slightly increased the acetic acid content whereas mild increase in lactic acid was produced by Lh138. The patterns of volatiles were dependent on the strain which reflect their distinct enzymatic machineries: LhB02 and Lh209 produced a greater diversity of compounds, while Lh138 was the least producer strain. Extracts inoculated with LhB02 and Lh 209 were characterized by ketones, esters, alcohols, aldehydes, and acids, whereas in the extracts with Lh138 the main compounds belonged to aromatic, aldehydes, and ketones groups. Therefore, Lh209 and LhB02 could represent the best cheese starters to improve and intensify the flavor, and even a starter composed by combinations of LhB02 or Lh209 with Lh138 could also be a strategy to diversify cheese flavor.

Influence of chymosin type and curd scalding temperature on proteolysis of hard cooked cheeses.

In this work, we studied the influence of the type of coagulant enzyme and the curd scalding temperature on the proteolysis and residual coagulant and plasmin activities of a cooked cheese, Reggianito, in the interest of reducing ripening time. A two-factor experimental design was applied in two levels: type of coagulant enzyme, bovine chymosin or camel chymosin, and curd scalding temperature, 50 or 56 °C. The experimental treatments were applied in Reggianito cheese making experiments, and the samples were ripened for 90 d at 12 °C. Scalding temperature influenced residual coagulant activity; the cheeses cooked at 50 °C had significantly higher activity than those treated at 56 °C. In contrast, scalding temperature did not modify plasmin activity. Proteolysis was primarily affected by curd cooking temperature because chymosin-mediated hydrolysis of αs1 casein was slower in cheeses treated at 56 °C. Additionally, the nitrogen content in the cheese soluble fractions was consistently lower in the cheeses scalded at 56 °C than those cooked at 50 °C. A significant influence of the type of coagulant enzyme was observed, especially in the nitrogen fractions and peptide profiles, which demonstrated that camel chymosin was slightly less proteolytic; however, these differences were lower than those caused by the scalding temperature.

Technological and probiotic role of adjunct cultures of non-starter lactobacilli in soft cheeses.

The influence of two cheese-isolated Lactobacillus strains on cheese composition, acceptability and probiotic capacity was assessed. Soft cheeses with and without the addition of Lactobacillus plantarum I91 or Lactobacillus paracasei I90 were prepared. Gross composition was assessed and secondary proteolysis was described by soluble fractions and free amino acids profiles. Acceptability was determined by a panel of 98 non-trained consumers. Cheeses harboring added Lactobacillus strains were also studied in vivo to evaluate their probiotic capacity. Gross composition of the cheeses was similar for control and treated (Lactobacillus-added) cheeses. Peptidolysis increased in cheeses with added lactobacilli, which was evidenced by a higher free amino acid content. Overall, the acceptability of the cheeses was good: 65%-80% of the consumers said that they "liked very much" or "liked" the cheeses. Cheeses with L. plantarum I91 showed the highest changes in composition and proteolysis and were the most accepted ones. On the contrary, composition of cheeses with L. paracasei I90 was similar to that of the controls, but these samples were less accepted than cheeses without lactobacilli. The oral administration of cheese containing L. plantarum I91 or L. paracasei I90 proved to be safe and able to enhance the number of IgA + cells in the small intestine lamina propria of mice. The use of selected strains of NSLAB exerted a technological and probiotic role: it contributed to the standardization of cheese quality and induced benefic health effects at the gut mucosa in vivo.