Testing for sensory threshold in drinking water with added calcium: a first step towards developing a calcium fortified water

Background: Food fortification is an effective strategy that has been recommended for improving population calcium inadequate intakes. Increasing calcium concentration of water has been proposed as a possible strategy to improve calcium intake. The objective of this study was to determine the sensory threshold of different calcium salts added to drinking water using survival analysis. Methods: We performed the triangle test methodology for samples of water with added calcium using three different calcium salts: calcium chloride, calcium gluconate and calcium lactate. For each salt, a panel of 54 consumers tested seven batches of three water samples. Data were adjusted for chance and sensory threshold was estimated using the survival methodology and a discrimination of 50%. Results: The threshold value estimation for calcium gluconate was 587 ± 131 mg/L of water, corresponding to 25% discrimination, for calcium lactate was 676 ± 186 mg/L, corresponding to 50% discrimination, and for calcium chloride was 291 ± 73 mg/L, corresponding to 50% discrimination. Conclusions: These results show that water with calcium added in different salts and up to a concentration of 500 mg of calcium/L of water is feasible. The calcium salt allowing the highest calcium concentration with the lowest perceived changes in taste was calcium gluconate. Future studies need to explore stability and acceptability over longer periods of time.

Anti-Biofilm Formation of an Adhesive Containing Calcium Salts of Acidic Monomers against Oral Candida Related to Root Caries

The proportion of older people within the general population is expanding due to the decline of birth rate and the increase of life expectancy. Increasing elderly populations, which is retaining its teeth longer, leads to oral health problems, for example, root caries. The main etiological factor for the initiation and development of root caries is the appearance of cariogenic biofilm. The acid-producing and acid-tolerant bacteria and oral yeast, such as Candida albicans are the major contributors in root caries formation. A new generation of adhesives is developed with several modifications for the prevention of dental caries by incorporating antimicrobial components. The aim of this study was to investigate the antimicrobial effect of adhesive containing calcium salt of acidic monomers on the biofilm formation of oral Candida related to root caries. In the experiments, the flat-bottom surfaces of 96-well plate were painted with an adhesive containing calcium salts of 4-methacryloxyethyl trimellitic acid (CMET) and 10-methacryloyloxydecyl dihydrogen calcium phosphate (MDCP) (Bio-Coat, CA, Sun Medical, Japan). Then they were LED light-cured and coated with sterile saliva at 37 °C for 60 min. The biofilm formation was made by adding of Candida albicans (ATCC 10238 and two clinical strains) suspensions (107 colony forming unit/mL) and incubated at 37°C for 24 h. The amount of vital biofilm was determined by WST-8 Microbial Cell Counting Kit (Dojindo Molecular Technologies, USA). All experiments were done in triplicate and repeated three times. Statistical analysis was performed using Student’s t-test. The results clearly showed that adhesive could significantly inhibit biofilm formation of all tested Candida compared with a control. This suppressive effect was not different among the strains of Candida. The percentages of vital biofilm reduction were 25% to 40%. The ability of this adhesive to suppress biofilm of oral yeast may be its antimicrobial property of acidic monomer or the effect of calcium ion within the adhesive, which can alter Candida cell morphology, and influence their structures or process of biofilm formation. In conclusion, an adhesive containing calcium salts of acidic monomers could significantly inhibit biofilm formation of C. albicans. This adhesive could be effectively applied to exposed root surfaces to prevent or inhibit the progression of root caries. Further studies are necessary to clarify the effect on multispecies biofilm, on long-term activity, and in vivo conditions.

Effects of Calcium Salts on the Physicochemical Quality of Cured Beef Sausages during Manufacturing and Storage: A Potential Calcium Application for Sausages with Alginate Casings

The impacts of adding calcium chloride (CaCl2) and calcium lactate (CaLac) with different concentrations (0%, 0.2%, 0.4%, and 0.7%) on the physicochemical properties of cured beef sausages were investigated in this study. Meat color, pH, lipid oxidation, and cooking loss were measured at respective manufacturing stages (ground beef, raw chopped batter, and after cooking). Additionally, meat color, pH, lipid oxidation, nitrosylhemochrome, residual nitrite, and texture profiles of vacuum-packaged sausages were evaluated during seven days of storage. Compared with the control (no Ca added), both calcium salts resulted in deteriorative color and texture properties, and promoted pH decline, cooking loss, and lipid oxidation of sausages during manufacturing and storage. However, increased calcium salt addition led to the reduction of residual nitrite over time. Compared to CaCl2 addition, 0.2–0.4% CaLac resulted in greater redness and oxidative stability and softer texture. These results may be useful when considering calcium salt additions in sausages, for the purpose of co-extruded sausages coated with alginate where Ca salts are used to form the casing during the co-extrusion of the sausages.

Bonding Reactions of Dental Self-Adhesive Cements with Synthetic Hydroxyapatite as a Function of the Polymerization Protocol

Objectives. This study evaluated the influence of the cement composition and different polymerization protocols on the bonding chemical interaction of self-adhesive cements with synthetic hydroxyapatite. Materials and Methods. Two commercial self-adhesive resin cements (RelyX U200 and Maxcem Elite) were selected, manipulated, mixed with hydroxyapatite dry powder (HAp), dispensed into molds, and distributed into three groups according to polymerization protocols: immediate photoactivation (IP); delayed photoactivation, 10 min self-curing and light-curing (DP); and chemical activation (CA, no light exposure). The detailed chemical information, at atomic scale, on the surface and deeper into the bulk of self-adhesive cement/hydroxyapatite mixtures was evaluated with X-ray photoelectron spectroscopy (XPS). Results. Chemical elements were detected in both cements, such as Na, O, Ca, C, P, and Si. Other elements were detected in minor concentrations. RelyX U200 exhibited the most intense formation of calcium salts products when the cement/HAp mixtures were photoactivated (immediate or delayed). RelyX U200/HAp mixture under delayed photoactivation (DP) also exhibited higher binding energy between calcium moieties of the HAp and methacrylates in the cement. A higher energy difference in the interaction of HAp with the cement comparing the bulk and surface areas was observed when RelyX U200 underwent the delayed photoactivation protocol. Maxcem Elite exhibited an increased chemical reactivity when either chemically activated or immediately photoactivated and a higher binding energy of the carboxyl groups bonded to the calcium of HAp when chemically activated. Conclusions. The interaction of cements with hydroxyapatite is chemical in nature and leads to the formation of calcium salts, which may favor better integrity and longevity of adhesive restorations. The polymerization protocol affects the chemical interaction in mixtures of self-adhesive cements and hydroxyapatite, influencing the formation of these salts and the establishment of intermolecular interactions between the HAp and the cements.

Effects of the association between whole cottonseed and calcium salts of fatty acids on nutrient intake, feedlot performance, and carcass characteristics of Bos indicus animals offered a high-concentrate diet

This experiment evaluated the effects of feeding whole cottonseed (WC) and/or calcium salts of fatty acids (CSFA) on dry matter intake (DMI), performance, and carcass characteristics of Bos indicus animals receiving a high-concentrate diet during the finishing phase. On day 0, 96 Nellore bulls were blocked according to initial shrunk body weight (BW; 302 ± 26.7 kg) into group pens (4 animals/pen) and, within blocks, pens were randomly assigned to receive: 1) 15% of WC and 2% of CSFA [dry matter (DM) basis] of palm, cottonseed, and soybean oil (15WC; n = 6), 2) 10% of WC and 3% of CSFA (DM basis) of palm, cottonseed, and soybean oil (10WC; n = 6), 3) 5% of WC and 4% of CSFA (DM basis) of palm, cottonseed, and soybean oil (5WC; n = 6), and 4) 0% of WC and 5% of CSFA (DM basis) of palm, cottonseed, and soybean oil (0WC; n = 6). Diets were formulated to be isocaloric, isonitrogenous, and isolipidic. Experimental period lasted 108 days, whereas dry matter intake (DMI) was evaluated daily and blood samples and carcass measurements were obtained on days 0, 55, and 108 of the study. Upon slaughter on day 109, steaks were collected for determination of the chemical and fatty acid (FA) profile of the meat. No treatment effects (P ≥ 0.35) were observed on DMI, performance, average daily gain (ADG), carcass ultrasound measurements, and chemical variables of the steak. Nonetheless, including WC into the diets increased C12:0, C16:0, C16:1 trans-9, C17:0, C18:0, C18:1 cis-9, C18:2 cis-9,cis-12, C18:3 cis-9,cis-12,cis-15, saturated, and unsaturated FA intake (P < 0.01). Moreover, adding WC increased DMI fluctuation and feed efficiency (P = 0.03), but decreased marbling (P ≤ 0.03). A treatment × day interaction was observed (P < 0.01) for serum leptin concentration, as 10WC animals had greater leptin concentration on d 103 vs. other treatments (P < 0.01). Regarding steak FA profile, WC addition into the diet increased C18:2 cis-7,trans-9 and C18:3 cis-9,cis-12,cis-15 (P < 0.001), whereas saturated FA was quadratically affected (P = 0.02) and unsaturated FA was reduced for 15WC (P < 0.04). In summary, increasing levels of CSFA into isolipidic finishing diets containing WC did not negatively impact feedlot performance, but reduced feed efficiency and increased marbling scores of Bos indicus bulls, demonstrating its feasibility as a technology to improve carcass traits of low-marbling animals.

Testing for sensory threshold in drinking water with added calcium: a first step towards developing a calcium fortified water

Background: Food fortification is an effective strategy that has been recommended for improving population calcium inadequate intakes. Increasing calcium concentration of water has been proposed as a possible strategy to improve calcium intake. The objective of this study was to determine the sensory threshold of different calcium salts added to drinking water using survival analysis. Methods: We performed the triangle test methodology for samples of water with added calcium using three different calcium salts: calcium chloride, calcium gluconate and calcium lactate. For each salt, a panel of 54 consumers tested seven batches of three water samples. Data were adjusted for chance and sensory threshold was estimated using the survival methodology and a discrimination of 50%. Results: The threshold value estimation for calcium gluconate was 587 ± 131 mg/L of water, corresponding to 25% discrimination, for calcium lactate was 676 ± 186 mg/L, corresponding to 50% discrimination, and for calcium chloride was 291 ± 73 mg/L, corresponding to 50% discrimination. Conclusions: These results show that water with calcium added in different salts and up to a concentration of 500 mg of calcium/L of water is feasible. The calcium salt allowing the highest calcium concentration with the lowest perceived changes in taste was calcium gluconate. Future studies need to explore stability and acceptability over longer periods of time.

Investigation of the dependences of the rheology of calcium alginate solutions on concentration, temperature and shear rate

The main problem: The rheological properties of calcium salts are of theoretical and practical interest for a modern researcher. The theoretical interest is primarily related to the search for general patterns and manifestations of the rheological properties of solutions of calcium salts. The practical component is based on the search for patterns and dependencies of the properties of solutions on the structure and composition of the object of study. Such chemicals as calcium salts are of particular practical interest, they are widely used in various fields, such as the food, chemical and pharmacological industries. Hydrophilic high-molecular solutions of alginates, namely calcium alginate, are actively used in the preparation of soft dosage forms, the manufacture of jelly masses in confectionery, act as thickeners in the food industry. They are characterized by a fairly high percentage of viscosity at low concentrations, bioavailability, prolonging effect, absence of irritating properties, biocompatibility with many polymers, which is especially important in the pharmaceutical industry and medicine. The use of calcium salts for these purposes is currently very promising, since these organic salts have a number of unique properties associated with gelation. Purpose: This paper contains the results of studying the features of the rheology of calcium alginate solutions. A concentration range of 0.1-0.7 % was chosen for the studies, which is sufficient to avoid gelation at room temperature. The dependence of viscosity on concentration, temperature (in the range of 25-45 °C) and shear rate were studied. Methods: Analysis of theoretical sources, observation, comparison of results. The rheological characteristics of the obtained substances were studied using a capillary viscometer. The measurements were carried out in the temperature range of 25-45°C. Results and their significance: it was found that there is a significant dependence of viscosity on concentration and temperature. For concentrations of 0.3 – 0.7 %, a similar type of dependence is observed, in contrast to solutions with a concentration of 0.1 % . Explanations of these dependencies were proposed.

Productive and reproductive performance and blood chemistry on grazing Brahman replacement heifers supplemented with fatty acids and protein

To evaluate the effect of calcium salts of long-chain fatty acids (CaLCFA) and protein supplementation on body weight (BW), average daily gain (ADG), pregnancy rate (PR), and blood chemistry, 57 Brahman heifers with 309.1 ± 3.04 kg BW and 1,010 ± 8.51 days of age, were divided into three BW uniform groups and assigned for 102 days to three treatments under a completely randomized design: 1) grazing forage only (F); 2) F+CaLCFA, and 3) F+CaLCFA+protein-energy mix (CaLCFA+CP) with 453 protein g/kg, containing mainly (g/kg) CaLCFA (200), hydrolyzed feather meal (300), and cornmeal (375). About 0.2 and 1 kg/animal/d of CaLCFA and CaLCFA+CP were offered, respectively, with an average intake of 200 and 192 g/animal/d for the same order of supplements. The breeding period (BP) lasted for 45 days and started 57 days after beginning the supplementation period. Body weight showed a treatment × time interaction (p < 0.01), being different at the end of the BP (348; 338 and 331 kg, respectively for CaLCFA, CaLCFA+CP, and F). Average daily gain (g/d) was higher (p < 0.01) for CaLCFA (358) than for CaLCFA+CP (281), and lower for F (206). Overall, PR was higher (p < 0.05) for CaLCFA+CP (68.4 %) and lower for F (36.8 %). Cholesterol (mg/dL) was higher (p < 0.05) for CaLCFA+CP (139) and lower for F (117). Calcium salts of long-chain fatty acids and CaLCFA+CP supplementation improved BW and ADG of Brahman heifers at first mating, while PR and cholesterol increased only with CaLCFA+CP supplementation.