The impact of COVID-19 lockdown on food priorities. Results from a preliminary study using social media and an online survey with Spanish consumers.

This preliminary study describes the impact of the COVID-19 health crisis on people's interests, opinions, and behaviour towards food. Here, the evolution of people's internet searches, the characteristics of the most watched YouTube videos, and Tweeted messages in relation to COVID-19 and food was studied. Additionally, an online questionnaire (Spanish population, n = 362) studied changes in food shopping habits during the lockdown, motivations behind the changes, and perceived reliability of the information received from media. Results showed initial trending searches and most watched YouTube videos were about understanding what COVID-19 is and how the illness can progress and spread. When the official statement of a pandemic was released, trending searches in relation to food and shopping increased. Data retrieved from Twitter also showed an evolution from shopping concerns to the feeling of uncertainty for the oncoming crisis. The answers to the online questionnaire showed reduction of shopping frequency but no changes in shopping location. Products purchased with higher frequency were pasta and vegetables (health motivations), others were purchased to improve their mood (nuts, cheese, and chocolates). Reduced purchasing was attributed to products with a short shelf-life (fish, seafood) or because they were unhealthy and contributed to gained body weight (sugary bakery goods) or mood (desserts). Statements made by experts or scientists were considered by consumers to be the most reliable.

Oral processing and dynamics of texture perception in commercial gluten-free breads.

There is an increasing demand for gluten-free products, with the texture being a critical aspect. The aim of this work was to study the food bolus properties of gluten-free breads in relation to the dynamics of sensations perceived during its consumption. In this study, five-commercial gluten-free breads and two regular breads were analysed for their texture, crumb structure, and moisture content. Bread bolus particle size after three chews, bolus characteristics at the swallowing point, and oral activity were determined. The dynamics of textural sensations during bread consumption was evaluated using the temporal dominance of sensations (TDS) technique. Texture and structure properties vary among gluten-free breads being some of them close to regular breads (crumb with more and smaller cells that shows low hardness and high springiness) that lead to different in-mouth breakdown and TDS patterns. At the beginning, harder breads with low springiness values resulted in hard dominant sensations, in contrast, breads with low hardness and high springiness values were perceived soft and spongy. Breads that fragmented into a greater number of small size particles created crumbly and sandy sensations, characteristic of gluten-free breads with large air cell sizes. Compact sensation appeared in breads with low saliva uptake during bolus formation, while pasty and sticky sensations were related to a cohesive and adhesive bolus, respectively. Not only structure and mechanical properties, but also its oral behaviour in terms of fragmentation and bolus formation can fully explain the dynamics of texture perception of gluten-free breads.

Relating texture perception of cooked ham to the bolus evolution in the mouth.

The aim of the present study was to characterize the dynamics of the bolus formation that take place during mastication of commercial cooked ham samples. In addition, the relationships between these properties and texture perception were studied. Five commercial samples which presented different mechanical properties and moisture contents were studied. Ten participants were asked to chew the cooked ham samples normally and to expectorate the bolus after different chewing periods. Oral activity measurements (chewing time and number of chewing strokes), moisture content, saliva uptake and particle size distribution in the boluses were obtained. Seventeen participants evaluated the sensory perceptions generated over the sample consumption time, using the Temporal Check-All-That-Apply (TCATA) method. The results revealed that the duration of mastication and number of chewing cycles through to swallowing varied significantly among the cooked ham samples and were mainly related to instrumental texture parameters. The pattern of fragmentation under mastication also varied greatly between samples. Sensations of softness and hardness during ham consumption were again linked to instrumental texture parameters (TPA hardness, TPA chewiness and shear force). The perception of fibrousness was related to the degree of fragmentation of the ham in the mouth, and juiciness seemed to be related to the amount of saliva taken up by the product.

How is an ideal satiating yogurt described? A case study with added-protein yogurts.

Protein is recognized as the macronutrient with the highest satiating ability. Yogurt can be an excellent basis for designing satiating food as it is protein-based food product. Five different set-type yogurts were formulated by adding extra skim milk powder (MP), whey protein concentrate (WPC), calcium caseinate (CAS) or a blend of whey protein concentrate with calcium caseinate (CAS-WPC). A control yogurt without extra protein content was also prepared. Differences in sensory perceptions (through CATA questions) were related to the consumers' expected satiating ability and liking scores (of several modalities). In addition, an "Ideal satiating yogurt" was included in the CATA question to perform a penalty analysis to show potential directions for yogurt reformulation and to relate sensory and non-sensory yogurt characteristics to satiating capacity.

Relating dynamic perception of reformulated cheese pies to consumers' expectations of satiating ability.

Designing satiating food is not an easy task. Food reformulation is normally done by altering the proportion of basic ingredients or by adding new minor ingredients. In general, the texture varies concomitantly with these changes, altering the way the food is processed orally and the complete eating experience. This highlights the interest of discovering how variations in minor ingredients influence texture and how this affects the dynamics of the oral trajectory. Six cheese pie formulations were prepared: basic recipe (Base), no egg (-Egg), no corn starch (-Corn starch) no sugar (-Sugar), added diary cream (+Cream) and extra skimmed milk powder (+Milk powder). Temporal dominance of sensations was used to show that the appearance and disappearance of each texture sensation dominance experienced in the mouth during the eating process differed among the six pies, as did their relation to the consumers' expectation of satiating capacity scores and to the changes in composition. Two extreme behaviors were found: suppression of egg/addition of extra milk powder made the pies initially drier and harder, while suppression of corn starch/addition of cream gave the samples a soft, moist early sensation. The former elicited higher expectations of satiating capacity. In addition, overall liking, liking evolving with time (dynamic liking) and the level of several key texture attributes' divergence from those of an "ideal" cheese pie were evaluated on bipolar just-about-right scales and through penalty analysis to gain insights into potential directions for reformulating acceptable pies.

Relating the effects of protein type and content in increased-protein cheese pies to consumers' perception of satiating capacity.

Since proteins have been shown to have the highest satiation-inducing effects of all the macronutrients, increasing the protein level is one of the main strategies for designing foods with enhanced satiating capacity. However, few studies analyze the effect that protein addition has on the texture and flavor characteristics of the target food item to relate it to the expected satiating capacity it elicits. The present work studied cheese pies with three levels of soy and whey proteins. Since the protein level altered the rheological behavior of the batters before baking and the texture of the baked pies, the feasibility of adding several protein levels for obtaining a range of final products was investigated. A check-all-that-apply questionnaire containing 32 sensory and non-sensory characteristics of the samples was given to consumers (n = 131) who also scored the perceived samples' satiating capacity. The results showed that the type and content of protein contributed distinctive sensory characteristics to the samples that could be related to their satiating capacity perception. Harder and drier samples (high protein levels) were perceived as more satiating with less perceptible sweet and milky cheese pie characteristic flavors. Soy contributed an off-flavour. These results will contribute to a better understanding of the interrelation of all these factors, aiding the development of highly palatable solid foods with enhanced satiating capacities.

High hydrostatic pressure treatment provides persimmon good characteristics to formulate milk-based beverages with enhanced functionality.

High hydrostatic pressure (HHP) applied during food processing can improve the retention of food quality attributes and nutritional values in comparison with pasteurization. Persimmon is a good source of bioactive compounds but it is a seasonal fruit that cannot be consumed throughout the year. The aim of this work was to compare the HHP and pasteurization treatments to formulate milk-based beverages containing this carotenoid rich ingredient and to evaluate their performance in these beverages. The carotenoid and tannin contents of persimmon were determined and the microstructure and rheology of the new milk-based persimmon beverages were examined. The results showed that HHP treatment favoured the release of carotenoids from the fruit matrix and precipitation of the tannins. The milk-based beverages prepared with the high-pressure persimmon presented the best rheological properties because unlike the untreated and pasteurized persimmon milk-based beverages, they did not form a gel-like structure or separate out.

Active compounds and distinctive sensory features provided by American ginseng (Panax quinquefolius L.) extract in a new functional milk beverage.

American ginseng (Panax quinquefolius L.) has recognized neurocognitive effects, and a ginsenoside-rich extract of the root of the plant has been shown to improve cognitive functions in young adults. This study aimed at assessing the chemical and sensory profiles of a UHT-treated, low-lactose functional milk containing American ginseng. Individual ginsenosides in the milk were analyzed by HPLC. Descriptive sensory analysis was performed by a trained panel to quantitatively document sensory changes resulting from the addition of ginseng and the UHT process on flavored and unflavored milks. Consumer acceptance of the product was also investigated. Total ginsenoside content in the UHT-treated milk enriched with the ginseng extract after UHT process treatment was 7.52 mg/100 g of milk, corresponding to a recovery of 67.6% compared with the content in the unprocessed extract. The intake of 150 to 300 mL of this ginseng-enriched milk provides the amount of total ginsenosides (11.5 to 23 mg) necessary to improve cognitive function after its consumption. Both the presence of ginsenosides and their thermal treatment affected some sensory properties of the milk, most notably an increase in bitterness and metallic taste, the appearance of a brownish color, and a decrease in milky flavor. Levels of brown color, bitterness, and metallic taste were highest in the industrially processed ginseng-enriched milk. The bitterness attributable to ginseng extract was reduced by addition of vanilla flavor and sucralose. A consumer exploratory study revealed that a niche of consumers exists who are willing to consume this type of product.

Influence of nutritional knowledge on the use and interpretation of Spanish nutritional food labels.

UNLABELLED: The present study analyzed the nutritional knowledge of Spanish consumers and its relationship with the correct use of food labels. Consumers were asked about their nutritional knowledge and some functional foods and about their understanding of food labeling and their use of it to select healthy food. A 2-part questionnaire was employed. The 1st part concerned their knowledge of nutritional facts, including their knowledge about macronutrients and perception of certain functional foods, while the 2nd part addressed some questions regarding food labels. The results revealed no statistically significant differences in nutritional knowledge by either age or gender, but a direct relationship with educational level. The association between nutritional knowledge and the perception and understanding of food labeling showed that the nutritional label rarely influenced the food purchases of the group with low nutritional knowledge, who considered that this information was too technical. More than half of the consumers did not consider the calorie or sugar content important for selecting food. In addition, the group with low nutritional knowledge stated that they never or rarely looked at the food labels to check whether it was low-fat food that they were buying. PRACTICAL APPLICATION: Knowing the status of the consumer's nutritional knowledge allows health campaigns to be designed; considering the influence of cultural factors and the perception of food labeling is very useful for promoting better nutritional information.

Evaluation of yogurt and various beverages as carriers of lactic acid bacteria producing 2-branched (1,3)-ß-D-glucan.

Probiotic cultures are increasingly being incorporated into a wide variety of food products. Although lactobacilli and bifidobacteria are the most frequently used, other lactic acid bacteria (LAB) have been reported to be potential probiotics. Of these, the cider isolates Pediococccus parvulus (strains 2.6 and CUPV22) and Lactobacillus suebicus CUPV221 produce a 2-branched (1,3)-ß-d-glucan exopolysaccharide that decreases serum cholesterol levels and affects the activation of human macrophages. For this reason, these 3 strains were incorporated into yogurt, orange juice, and 2 juice-milk beverages to evaluate the effect of the food matrix on the resistance of these strains to simulated gastrointestinal tract conditions. Our results showed that incorporation of the LAB did not significantly affect the physical and rheological properties of the food matrices tested. When incorporated in yogurt, LAB strains population decreased by 2 to 3 log orders of magnitude during the shelf life of the product (28 d). However, no significant decrease was observed in the juice and juice-milk beverages during the same storage period, except for Lb. suebicus, whose viability decreased by 3 log orders of magnitude. When strains were subjected to gastrointestinal tract conditions, a decrease in the survival was observed at the lower pH (1.8). However, incorporation of these LAB strains into orange juice increases their resistance to lower pH conditions, thus improving survival to gastrointestinal stress. Moreover, a protective effect was observed for P. parvulus CUPV22 and 2.6 to gastric stress in juice-milk beverages and to gastrointestinal stress in yogurt. Lactobacillus suebicus CUPV221 did not survive when incorporated into yogurt and juice-milk beverage.

Sensory properties determined by starch type in white sauces: effects of freeze/thaw and hydrocolloid addition.

The effect of 5 types of starch (rice, potato, waxy corn, corn, and modified waxy corn) on the sensory properties of white sauces was studied. A comparative study was also made of variations resulting from freezing/thawing and effect of replacing 0.15% starch with 2 nonstarchy hydrocolloids, xanthan gum (XG), or locust bean gum (LBG) in samples to be frozen. The sensory properties were studied through descriptive analysis by a panel of 10 trained judges. Principal components analysis and cluster analysis were used to group each of the samples according to the scores for consistency, resilience, graininess, thickness, heterogeneity, creaminess, and mouth coating, the sensory attributes which were chosen to define the sauces under study. Significant differences were found between the different starches employed: the rice and modified starches presented similar behavior to each other, as did the potato starch and corn starch, while the waxy starch sauce stood apart from the rest because of its resilience. The freeze/thaw cycle had the greatest effect on the corn-starch sauce, increasing its graininess and heterogeneity values owing to retrogradation. Adding XG or LBG to the sauces subjected to a period of freezing/thawing did not have a significant effect on the sensory attributes of the reheated sauces made with rice, potato, or waxy or modified starch, but lower graininess and heterogeneity values were observed in the sauce made with corn starch.

Effect of a new emulsifier containing sodium stearoyl-2-lactylate and carrageenan on the functionality of meat emulsion systems.

The emulsion capacity and stability of a new emulsifier containing sodium stearoyl lactylate plus iota carrageenan (SSL/iC) in comparison to caseinate and soy isolate was analysed. The emulsion capacity and stability of SSL/iC in oil/water (O/W) model system emulsions was higher than shown by caseinate and soy isolate. However, the O/W emulsion stability was negatively affected by sodium chloride addition, but positively affected by an increase in temperature. Meat batters were made with caseinate, soy isolate, and SSL/iC at the minimum concentration that showed a good performance (>75% stability) in the O/W emulsions. The emulsifier SSL/iC produced high cook yields and good stability when used in meat batters. However, the cooked meat batters containing SSL/iC showed texture characteristics highly detrimental to the sensory analysis. On the other hand, the addition of 2% potato starch reduced the differences in texture parameters among the samples made with the different emulsifiers.

Textural and sensory characteristics of whole and skimmed flavored set-type yogurt during long storage.

A study of refrigerated storage (10 degrees C for 91 d) of whole and skimmed flavored set-type yogurt was made. Comparison with storage at 20 degrees C for 21 d and 30 degrees C for 3 d (accelerated) was also carried out. Refrigerated storage yogurts were assessed by a trained panel and by a consumer panel. Trained-panel scores were correlated to instrumental data, and the acceptability data for long storage were studied using consumer criteria. In all cases, after-storage pH values barely changed over storage time, indicating that the yogurt samples did not develop much acidity under any of the storage conditions studied. The profile of the instrumental texture curves obtained corresponded to a firm gel, which broke after a plunger penetrated the sample, and the firmness values of the whole yogurt were lower than for the skimmed yogurt under all the storage conditions studied. From a microbiological point of view, the viability of the yogurts was adequate at the different storage times and temperatures studied, although those stored at 10 degrees C for long periods would not comply with some countries' minimum requirements. Logistic regression of the data from a 50-consumer sensory evaluation showed that the probability of the whole yogurt being accepted after 91 d storage at 10 degrees C was around 40%, whereas for the skimmed yogurt it was only 15%, largely because the skimmed yogurt developed certain negative attributes at an earlier stage of storage than the whole yogurt.

Postmortem meat quality and sex affect textural properties and protein breakdown of dry-cured ham.

Texture measurements by instrumental texture profile analysis (TPA) and protein degradation analysis by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) were performed on 30 dry-cured hams resulting from four different post-mortem meat qualities categories (PSE, RSE, RFN and DFD). The main differences were observed in dry-cured hams from PSE and RFN meat qualities. Penetration force (80%), hardness, springiness, cohesiveness and chewiness, were significantly lower (P<0.05) in PSE than in RFN quality classes. The rate of the ripening process was affected as a higher proteolysis and absence of fragments at 150 and 85 KDa in PSE in relation to RFN classes, and with an intermediate proteolysis of RSE and DFD classes. The effect of sex was observed as a significant (P<0.05) low hardness in the hams obtained from female pigs. The duration of the ripening, for a better uniformity in dry-cured ham production, should be adapted to the initial pH and to drip loss parameters of the raw material.

Effect of lyophilization on the mechanical characteristics of a large particle and on the behavior of immobilized bacterial spores.

The mechanical stability of the carrier and the behavior of the sensor element of a time-temperature integrator (TTI) after lyophilization and storage for 60 days at room temperature were studied. The results indicated that particles containing added starch at concentrations from 2 to 12% had good handling characteristics for use as TTI carriers, although mechanical resistance was lower by comparison with freshly prepared particles. Lyophilization reduced the number of viable microorganisms by 17 to 25%, depending on the length of the storage period. Variations were also observed in the count of surviving microorganisms after heating at 121 degrees C for 12 min. These variations, expressed as decimal reductions in the number of microorganisms, might reflect an effect of lyophilization on the thermal resistance of the immobilized spores.