Using maltodextrin and state diagrams to improve thermal transitions in tilapia fillet (Oreochromis spp.).

BACKGROUND: Tilapia (Oreochromis spp.) in the form of frozen fillets is one of the fishes with the highest commercial production levels worldwide. However, protein denaturation, membrane rupture, and lipid oxidation are commonly observed in fillets when stored at standard commercial freezing temperatures for long periods. This study proposes, for the first time, the use of maltodextrin and state diagrams to define processing strategies and suitable storage temperatures for fresh and dehydrated tilapia fillets. Differential scanning calorimetry (DSC) was used to study the effect of maltodextrin weight fractions ( W MD ) of 0, 0.4, and 0.8 on the thermal transitions of tilapia fillets as a function of solid mass fractions ( W s ). RESULTS: The glass transition temperature curve ( T g vs . W s ) and characteristic parameters of maximal freeze concentration ( T g ' , T m ' , W s ' ) of tilapia increased significantly with the addition of maltodextrin. Using developed state diagrams, freezing and storage temperatures of -22 °C, -15 °C, and -10 °C (P < 0.05) for long-term preservation were defined for tilapia fillets produced with W MD of 0, 0.4, and 0.8. CONCLUSION: Maltodextrin is an excellent alternative as a cryoprotectant and drying aid to increase the thermal parameters of tilapia fillets by achieving frozen storage temperatures above the standard commercial freezing temperature of -18 °C. © 2023 Society of Chemical Industry.

Evaluation of Two Active System Encapsulant Matrices with Quercetin and Bacillus clausii for Functional Foods.

Currently, demand for functional foods is increasing in the public interest in order to improve life expectations and general health. Food matrices containing probiotic microorganisms and active compounds encapsulated into carrier agents are essential in this context. Encapsulation via the lyophilisation method is widely used because oxidation reactions that affect physicochemical and nutritional food properties are usually avoided. Encapsulated functional ingredients, such as quercetin and Bacillus clausii, using two carrier agents' matrices-I [inulin (IN), lactose (L) and maltodextrin (MX)] and II [arabic (A), guar (G), and xanthan (X) gums)]-are presented in this work. A D-optimal procedure involving 59 experiments was designed to evaluate each matrix's yield, viability, and antioxidant activity (AA). Matrix I (33.3 IN:33.3 L:33.3 MX) and matrix II (33.3 A:33.3 G:33.3 X) exhibited the best yield; viability of 9.7 log10 CFU/g and 9.73 log10 CFU/g was found in matrix I (using a ratio of 33.3 IN:33.3 L:33.3 MX) and matrix II (50 G:50 X), respectively. Results for the antioxidant capacity of matrix I (100 IN:0 L:0M X) and matrix II (0 A:50 G:50 X) were 58.75 and 55.54 (DPPH* scavenging activity (10 µg/mL)), respectively. Synergy between matrices I and II with use of 100IN:0L:OMX and 0A:50G:50X resulted in 55.4 log10 CFU/g viability values; the antioxidant capacity was 9. 52 (DPPH* scavenging activity (10 µg/mL). The present work proposes use of a carrier agent mixture to produce a functional ingredient with antioxidant and probiotic properties that exceed the minimum viability, 6.0 log10 CFU/g, recommended by the FAO/WHO (2002) to be probiotic, and that contributes to the recommended daily quercetin intake of 10-16 mg/day or inulin intake of 10-20 g/day and dietary fibre intake of 25-38 g per day.

Volatile Compounds in Tofu Obtained by Soy Milk Fermentation with Lactobacillus plantarum BAL-03-ITTG and Lactobacillus fermentum BAL-21-ITTG.

Tofu is one of the main foods made with soybeans. The aim of this work was to evaluate the effect of L. plantarum and L. fermentum on the volatile compounds and sensorial profile of fermented tofu during ripening. The soy milk was fermented separately with two native strains (L. plantarum or L. fermentum) until reaching a pH of 5.5, and the fermented tofu was obtained. The tofu obtained by acidification with lactic acid was used as a control and was characterized by microbial survival (L. plantarum, L. fermentum, and P. freudenreichii) for 0, 20, and 40 days of storage at 15 °C. Moreover, the lactic and acetic acid content was determined by high-performance liquid chromatography (HPLC), and the volatile compounds were evaluated by gas. Chromatography-mass spectrometry (GC-MS). The results were analyzed by an ANOVA test (P < 0.05). After storage, the lactic acid bacteria (LAB) survived in the fermented tofu at a concentration higher than 8.0 log CFU/g after 40 days of storage. The shelf life of fermented tofu obtained by acidification was fewer than 20 days because of the presence of fungi and yeasts. The hexanal content was reduced by approximately 96% (P < 0.05) in the tofu obtained by fermentation compared with the control. This process for fermented tofu production employing two native strains could be used for industrial purposes.

Effect of linear and branched fructans on growth and probiotic characteristics of seven Lactobacillus spp. isolated from an autochthonous beverage from Chiapas, Mexico.

The effect that the fructans of Cichorium intybus and Agave salmiana have on health, as well as on the growth of some Lactobacillus species, has been demonstrated. The aim of this work was to evaluate the effect of linear and branched fructans on the growth of seven strains and some probiotic characteristics. The molecular identification of seven strains was performed. Moreover, the growth, resistance to antibiotics and simulated gastrointestinal conditions were also evaluated when these microorganisms were grown in a culture medium containing agave and chicory fructans. The strains were identified as Lactiplantibacillus plantarum, Lactiplantibacillus pentosus, Lactiplantibacillus fabifermentans and Lactiplantibacillus paraplantarum. The results suggest that the seven Lactobacillus strains were able to grow using agave (branched) and chicory (linear) fructans. The linear and branched fructans statistically influenced the kinetic parameters. The specific growth rate varied between 0.270 and 0.573 h-1 and the generation time between 1.21 and 2.45 h for all strains and culture media. All strains showed a growth of 9 Log CFU/mL in all the culture media. Production of lactic, acetic, propionic, butyric, formic and succinic acid was influenced by linear and branched fructans (p < 0.05). All the strains survived simulated gastrointestinal conditions greater than 83%. The resistance of Lactobacillus against ciprofloxacin and rifaximin was significantly affected by linear and branched fructans, but survival to gastrointestinal conditions was not affected by the type of substrate. These results highlight the use of the seven strains, which have probiotic potential; therefore, these could be applied in several biotechnological products.

Influence of Prebiotic Activity of Agave salmiana Fructans on Mucus Production and Morphology Changes in Colonic Epithelium Cell of Healthy Wistar Rats.

The beneficial health of evaluating prebiotic effect by the consumption of Agave salmiana fructans (A. salmiana fructans) was assessed in the epithelium of the cecum and proximal colon of Wistar rats fed at different doses for 35 days with regards to mucus production, morphological cell changes, and the serum concentration of tumor necrosis factor-α (TNF-α). Results showed a significant increase in mucus-secreting cells (P < 0.05) and a normal structure with preserved crypts, without morphological damage to colonic cells for a dose of 12.5% (w/w) with respect to the control and the other doses evaluated. The concentration of pro-inflammatory cytokine TNF-α was decreased significantly (P < 0.05) in the groups with doses of 10 and 12.5% (w/w) at 7 and 35 days, respectively. This effect was positively correlated with the reduction of inflammation in epithelial cells. This study provides direct evidence of the effects of the A. salmiana fructans on the colonic epithelium, demonstrating that a diet supplemented with 12.5% of fructans for 35 days exerts health benefits through the strengthening of the mucosa layer, which favors the adherence of the bacterial population and suppresses inflammation.

Physicochemical Properties, Antioxidant Capacity, Prebiotic Activity and Anticancer Potential in Human Cells of Jackfruit (Artocarpus heterophyllus) Seed Flour.

The general aim of this study was to evaluate physicochemical properties, prebiotic activity and anticancer potential of jackfruit (Artocarpus heterophyllus) seed flour. The drying processes of jackfruit seeds were performed at 50, 60 and 70 °C in order to choose the optimal temperature for obtaining the flour based on drying time, polyphenol content and antioxidant capacity. The experimental values of the moisture ratio during jackfruit seed drying at different temperatures were obtained using Page's equation to establish the drying time for the required moisture between 5 and 7% in the flour. The temperature of 60 °C was considered adequate for obtaining good flour and for performing its characterization. The chemical composition, total dietary fiber, functional properties and antioxidant capacity were then examined in the flour. The seed flour contains carbohydrates (73.87 g/100 g), dietary fiber (31 g/100 g), protein (14 g/100 g) and lipids (1 g/100 g). The lipid profile showed that the flour contained monounsaturated (4 g/100 g) and polyunsaturated (46 g/100 g) fatty acids. Sucrose, glucose, and fructose were found to be the predominant soluble sugars, and non-digestible oligosaccharides like 1-kestose were also found. The total polyphenol content was 2.42 mg of gallic acid/g of the sample; furthermore, the antioxidant capacity obtained by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) was 901.45 µmol Trolox/100 g and 1607.87 µmol Trolox/100 g, respectively. The obtained flour exhibited good functional properties, such as water and oil absorption capacity, swelling power and emulsifier capacity. Additionally, this flour had a protective and preventive effect which is associated with the potential prebiotic activity in Lactobacillus casei and Bifidobacterium longum. These results demonstrate that jackfruit seed flour has good nutritional value and antioxidant and prebiotic activity, as well as potential protective effects and functional properties, making it an attractive food or ingredient in developing innovative functional products.

Experimental data and predictive equation of the specific heat capacity of fruit juice model systems measured with differential scanning calorimetry.

Specific heat capacity ( C P ) is regarded as a fundamental parameter for the design, operation, and optimization of the heat transfer equipment widely used in the food industry. Using the calorimetric ASTM E1269-11 standard procedure, the C P -temperature ( C P ( T ) ) curves of fruit juice model systems prepared at different mass fractions of fructose/glucose/sucrose/citric acid/pectin and water were measured. Thus, experimental data of C P for solid samples in crystalline and amorphous states from -80 °C up to the melting temperature range and for aqueous samples from -80 to 110 °C were generated. In the tested temperature interval, the C P of crystalline, amorphous, and aqueous samples were found to be in the ranges of 0.037 ± 0.020 to 5.61 ± 0.04; 0.061 ± 0.004 to 3.12 ± 0.19, and 0.363 ± 0.05 to 3.24 ± 0.14 kJ/kg °C, respectively. Also, a generalized empirical equation based on the type and concentration of components was developed to predict the C P ( T ) curves of the studied samples. The proposed equation exhibited a low error sum of squares (SSE <  57.3) and a high coefficient of determination (R2 > 0.927). An analysis of variance (ANOVA) was performed with a confidence level of 95% (p < 0.05). The C P ( T ) curves were influenced by temperature, thermal transitions, water, solid types, and compound interactions. Glucose was one of the solids that most significantly influenced the C P values of samples. PRACTICAL APPLICATION: The experimental specific heat capacity data and empirical equation proposed in this study are relevant to the design, evaluation, and optimization of heat transfer equipment involved in many foods and biochemical industrial processes such as cryopreservation, frozen storage, freezing, chilling, drying, and the cooking of hard candies.

Effects of Agave Fructans, Inulin, and Starch on Metabolic Syndrome Aspects in Healthy Wistar Rats.

Healthy Wistar rats were supplemented during 20 weeks with commercial inulin (I) and Agave tequilana fructans (CAT), experimental fructans from A. tequilana (EAT) and A. salmiana (AS) mature stems, rice starch 10% (RS), and standard feed for rodents (C). Feed intake was kept steady, but with I, body weight and abdominal adipose tissue (6.01 g) decreased at the end. Glucose (mg/dL) (C, 120.52; I, 110.69; CAT, 105.75; EAT, 115.48; AS, 101.63; and RS, 121.82), total cholesterol (C, 89.89; I, 64.48; CAT, 68.04; EAT, 68.74; AS, 68.04; and RS, 82), and triglycerides (C, 84.03; I, 59.52; CAT, 68.56; EAT, 59.08; AS, 75.27; and RS, 81.8) kept being normal and without differences between fructans. At the end, there was a significant increase in lactic acid bacteria when the I and AS groups were compared to the C group (C, 9.18; I, 10.64; CAT, 10.34; EAT, 10.36; AS, 10.49; and RS, 9.62 log 10 CFU/g of feces). In addition, with fructans, there was an accelerated process in feces emptiness, Lieberkühn crypts kept their morphology, and there was an increment of goblet cells.

Thermal Study of Polyols for the Technological Application as Plasticizers in Food Industry.

In this work is presented the complete thermal analysis of polyols by direct methods such as simultaneous thermogravimetric and differential thermal analyzer (TGA-DTA), differential scanning calorimetry (DSC), modulated DSC (MDSC), and supercooling MDSC. The different thermal events in the temperature range of 113⁻553 K were identified for glycerol (GL), ethylene glycol (EG), and propylene glycol (PG). Boiling temperature (TB) decreased as GL > EG > PG, but increased with the heating rate. GL showed a complex thermal event at 191⁻199 K, identified as the glass transition temperature (Tg) and devitrification temperature (Tdv), and a liquid⁻liquid transition (TL-L) at 215⁻221 K was identified as the supercooling temperature. EG showed several thermal events such as Tg and Tdv at 154 K, crystallization temperature (Tc) at 175 K, and melting temperature (Tm) at 255 K. PG also showed a complex thermal event (Tg and Tdv) at 167 K, a second devitrification at 193 K, and TL-L at 245 K. For PG, crystallization was not observed, indicating that, during the cooling, the liquid remained as an amorphous solid.