Aspectos tecnológicos e sensoriais do iogurte de soja enriquecido com cálcio

O objetivo deste trabalho foi verificar a viabilidade de enriquecimento do iogurtede soja com cálcio, para que o produto apresentasse níveis deste mineral equivalentes ou superiores aos encontrados nos iogurtes tradicionais e mantivesse as propriedades tecnológicas e sensoriais adequadas. Foram testados cinco sais: carbonato, citrato, fosfato, gliconato e lactato de cálcio, na concentração de 600mg de cálcio elementar/l. Os produtos foram avaliados quanto ao tempo de fermentação, pH, acidez titulável, viscosidade, consistência, concentração de cálcio e propriedades sensoriais (testes de diferença do controle e aceitação). A adição de cálcio ao iogurte de soja na forma de citrato, fosfato, carbonato, gliconato e lactato de cálcio, apesar de provocar alterações na acidez titulável, viscosidade e consistência, não conferiu propriedades sensoriais indesejáveis ao produto e o tempo de fermentação não excedeu aos verificados nos processos industriais convencionais. Desta forma todos os sais testados se mostraram viáveis para o processo de enriquecimento do iogurte de soja com cálcio.

Whey And Soy Protein Supplements Changes Body Composition In Patients With Crohn's Disease Undergoing Azathioprine And Anti-tnf-alpha Therapy.

Crohn´s disease (CD) is a chronic transmural inflammation of the gastrointestinal tract of unknown cause. Malnutrition associated with active CD has been reduced although obesity has increased. Dietary strategies such as those with high-protein have been proposed to reduce body fat. This study compares the effects of two supplements on the nutritional status of CD patients. 68 CD patients were randomized in two groups: whey protein group (WP) and soy protein group (SP). Using bioimpedance analysis, anthropometry and albumin and pre-albumin dosages the nutritional status was measured before starting the intervention and after 8 and 16 weeks. The disease activity was determined by Crohn's Disease Activity Index and serum C-reactive protein dosage and dietary intake by 24h dietary recalls. Forty-one patients concluded the study and both supplements changed body composition similarly. Triceps skin fold thickness (p< 0.001) and body fat percentage (p=0.001) decreased, whereas mid-arm muscle circumference (p=0.004), corrected arm muscle area (p=0.005) and body lean percentage (p=0.001) increased. For Crohn's disease patients undergoing anti TNF-alpha and azatioprine therapies, supplementation with whey and soy proteins changes body composition through reduction of body fat and thus contributes to control inflammation.

Effects of isoflavone-supplemented soy yogurt on lipid parameters and atherosclerosis development in hypercholesterolemic rabbits: a randomized double-blind study

Background: There is increasing interest in natural treatments to control dyslipidemia and reduce the risk of cardiovascular disease. Previous studies have demonstrated the beneficial effects of soy yogurt fermented with Enterococcus faecium CRL 183 and of dietary isoflavones on the lipid profile. The purpose of the present study was to investigate the effects of isoflavone-supplemented soy yogurt, fermented with E. faecium CRL183, on lipid parameters and atherosclerosis development in rabbits with induced hypercholesterolemia. Methods: Forty-eight rabbits were randomly assigned to eight groups fed on the following diets for 60 days: C - control; IY - isoflavone-supplemented soy yogurt; H - hypercholesterolemic (1.0% cholesterol wt/wt diet); HY - hypercholesterolemic plus soy yogurt; HIY - hypercholesterolemic plus isoflavone-supplemented soy yogurt; HP - hypercholesterolemic plus placebo; HI hypercholesterolemic plus isoflavone and HE - hypercholesterolemic plus pure culture of E. faecium CRL 183. Serum lipids and autoantibodies against oxLDL (oxLDL Ab) were analyzed on days 0, 30 and 60 of the treatment and the atherosclerotic lesions were quantified at the end of the experiment. Results: Soy yogurt, soy yogurt supplemented with isoflavones and placebo promoted significant reductions in total cholesterol level (38.1%, 27.0% and 26.6%, respectively). Significant increases in serum HDL-C concentration relative to group H were detected in animals that ingested soy yogurt, with or without the isoflavone supplement (55.2%), E. faecium culture (43.3%) or placebo (35.8%). Intake of soy yogurt and soy yogurt supplemented with isoflavones prevented the rise of oxLDL Ab during the study period. The extent of atherosclerosis in the thoracic and abdominal aortas was reduced in the HIY, HY and HP groups. However, when the whole aorta was analyzed, animals treated with soy yogurt supplemented with isoflavones exhibited the greatest reduction (51.4%, P < 0.05) in atherosclerotic lesion area, compared to group H. Conclusion: Soy yogurt could be consumed as an alternative means of reducing the risk of cardiovascular disease by improving the lipid profile and inhibiting oxLDL Ab formation. Our findings also suggest that isoflavone supplementation may enhance the antiatherosclerotic effect of soy yogurt.

Effects of milk supplementation with skim milk powder, whey protein concentrate and sodium caseinate on acidification kinetics, rheological properties and structure of nonfat stirred yogurt

Milk supplementation with milk proteins in four different levels was used to investigate the effect on acidification and textural properties of yogurt. Commercial skim milk powder was diluted in distilled water, and the supplements were added to give different enriched-milk bases; these were heat treated at 90 degrees C for 5 min. These mixtures were incubated with the bacterial cultures for fermentation in a water bath, at 42 degrees C, until pH 4.50 was reached. Chemical changes during fermentation were followed by measuring the pH. Protein concentration measurements, microbial counts of Lactobacillus bulgaricus and Streptococcus thermophilus, and textural properties (G`, G ``, yield stress and firmness) were determined after 24 h of storage at 4 degrees C. Yogurt made with milk supplemented with sodium caseinate resulted in significant properties changes, which were decrease in fermentation time, and increase in yield stress, storage modulus, and firmness, with increases in supplement level. Microstructure also differed from that of yogurt produced with milk supplemented with skim milk powder or sodium caseinate. (C) 2009 Elsevier Ltd. All rights reserved.

Effect of ingestion of soy yogurt on intestinal parameters of rats fed on a beef-based animal diet

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Intake of isoflavone-supplemented soy yogurt fermented with Enterococcus faecium lowers serum total cholesterol and non-HDL cholesterol of hypercholesterolemic rats

The aim of this study was to obtain an isoflavone-supplemented soy yogurt, fermented with Enterococcus faecium CRL 183 and Lactobacillus helveticus ssp jugurti, with suitable sensory properties and to assess the effects of the final product on blood lipids in hypercholesterolemic rats. Four isoflavone supplementation procedures were tested, in which the isoflavone was added at these stages: (1) before heat-treatment; (2) after heating and before fermentation; (3) after fermentation and (4) in the okara (by-product of soy milk) flour stirred into the fermented product when consumed. The products were subjected to a test of sensory acceptability. To assess their potential hypocholesterolemic properties in vivo, four groups of rats were used: control (C), hypercholesterolemic (H), hypercholesterolemic plus fermented product (HF) and hypercholesterolemic plus isoflavone-supplemented fermented product (HFI). Hypercholesterolemia was induced in rats of groups H, HF and HFI by feeding them on a commercial rat chow to which cholesterol and cholic acid had been added. Total, HDL and non-HDL cholesterol and triglycerides were measured in the blood of the rats. No significant sensorial differences were detected among the samples of soy yogurt supplemented with isoflavones at various processing stages. Rats fed a fermented soy product enriched with isoflavones (HFI group) had significantly (P < 0.05) less serum total cholesterol (15.5%) compared with rats fed a hypercholesterolemic diet (H group). Non-HDL cholesterol was less (P < 0.05) in rats fed a fermented soy product enriched or not with isoflavones (27.4 and 23.2%) compared to H group. The HDL-C and triglyceride concentrations did not differ significantly among the groups. It was possible to obtain an isoflavone-supplemented soy yogurt with satisfactory sensory characteristics. The resulting supplemented soy yogurt was capable of producing a lipid-lowering effect in hypercholesterolemic rats, relative to the animals that did not consume this product.

Effects of isoflavone-supplemented soy yogurt on lipid parameters and atherosclerosis development in hypercholesterolemic rabbits: a randomized double-blind study

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antibiosis associated to Lactobacillus acidophilus growth .2. Optimization of some culture parameters in whey and soy milk medium

Whey supplemented with soy milk has been used as a low-cost alternative in the growth of Lactobacillus acidophilus for the production of antimicrobial compounds. Response Surface Metodology has been employed in order to study the effects of initial pH, incubation temperature and soy milk rate for supplementation in the production of antimicrobial substance. It has been observed that both tested microrganisms used (S. aureus and E. coli) were inhibited by antimicrobial substance produced by L. acidophilus. The results obtained with E. coli inhibition did not follow the employed statistical model. on the other hand, when the tested microorganism S. aureus was used, the best inhibition results have been obtained when L. acidophilus was incubated at 36.80 degrees C in whey with 5.6 initial pH and 31,90% (v/v) rate supplemented with soy milk. The analysed antimicrobial substances were nor acids neither hidrogen peroxid.

Optimization of yogurt production using demineralized whey

The effect of three independent fermentation variables: demineralized whey powder (0.0; 1.5 and 3.0%), lactic culture concentration (1.0; 2.0 and 3.0%) and mix treatment temperature (85; 90 and 95°C) was studied. Fermentation time to reach pH 4.3, instrumental consistency and appearance, visual consistency and taste of the product were evaluated. Product consistency increased as mix treatment temperature increased and demineralized whey powder decreased. The powder had a stronger influence on instrumental consistency than did temperature. Appearance was better when whey powder was used at 1.4 to 1.6%. Visual consistency decreased as whey powder increased but addition of demineralized whey powder did not negatively affect yogurt flavor.

Influence of carrageenan and total solids content on the rheological properties of lactic beverage made with yogurt and whey

The purpose of this work was to study the influence of carrageenan level (X 1) and total solids content of yogurt/whey mixture (X 2) on starter culture fermentation time, physicochetnical properties (pH, fat and total solids contents) and rheological characteristics of lactic beverages using response surface methodology. The physicochemical characteristics of the lactic beverages were similar to those of commercial products. All beverages showed non-Newtonian fluid behavior with thixotropy and yield stress. The total solids content of the lactic beverages had a greater influence on the rheological behavior of these products than the carrageenan level. Wide ranges of consistency measurements were observed by varying the stabilizer level and total solids content.

Effects of refrigeration, freezing and replacement of milk fat by inulin and whey protein concentrate on texture profile and sensory acceptance of synbiotic guava mousses

The effects of refrigeration, freezing and substitution of milk fat by inulin and whey protein concentrate (WPC) on the texture and sensory features of synbiotic guava mousses supplemented with the probiotic, Lactobacillus acidophilus La-5, and the prebiotic fibre oligofructose, were studied. The frozen storage (-18 +/- 1 degrees C), followed by thawing at 4 degrees C before the analyses, and the complete replacement of the milk fat by inulin plus WPC, led to significant differences in the instrumental texture parameters of mousses (P < 0.05). Nonetheless, these changes did not affect the sensory acceptability of the products studied. The frozen storage may be employed to extend the shelf-life of synbiotic guava mousses. Additionally, to obtain a texture profile similar to the traditional product, the simultaneous addition of inulin and WPC is recommended only for the partial replacement of milk fat in refrigerated and frozen mousses, and the total proportion of both ingredients together should not exceed 2.6%. (C) 2010 Elsevier Ltd. All rights reserved.

Sensory evaluation and physicochemical optimisation of soy-based desserts using response surface methodology

The objective of this study was to develop a dessert that contains soy protein (SP) (1%, 2%, 3%) and guava juice (GJ) (22%, 27%, 32%) using Response Surface Methodology (RSM) as the optimisation technique. Water activity, physical stability, colour, acidity, pH, iron, and carotenoid contents were analysed. Affective tests were performed to determine the degree of liking of colour, creaminess, and acceptability. The results showed that GJ increased the values of redness, hue angle, chromaticity, acidity, and carotenoid content, while SP reduced water activity. Optimisation suggested a dessert containing 32% GJ and 1.17% SP as the best proportion of these components. This sample was considered a source of fibres, ascorbic acid, copper, and iron and garnered scores above the level of `slightly liked` for sensory attributes. Moreover, RSM was shown to be an adequate approach for modelling the physicochemical parameters and the degree of liking of creaminess of desserts. (C) 2010 Elsevier Ltd. All rights reserved.

Acidification rates of probiotic bacteria in Minas frescal cheese whey

The acidification rates of Lactobacillus delbrueckii subsp. bulgarieus (Lb), Lactobacillus acidophilus (La), Lactobacillus rhamnosus (Lr), and Bifidobacterium animalis subsp. lactis (Bl) in co-culture with Streptococcus thermophilus (St) were studied in Minas frescal cheese whey. Effects of the co-culture composition and the final pH values on the kinetic parameters of acidification, post-acidification and counts of health promoting micro-organisms were also studied. Fermentation time to reach pH 4.5 was longer when St-Lr co-culture was used, while St-Lb had the shortest fermentation time when compared with the other co-culture combinations. All products showed development of acidity during the storage period and lowest values had been observed employing St-Bl co-culture. The technological interest of using M. frescal cheese whey for the production of a probiotic lactic beverage is discussed in this article. (C) 2007 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Yogurt from UHT milk: a review

Continuous heat treatment by UHT processing has attracted interest as an alternative to the batch-heating method conventionally used in the production of yogurt. Several studies have been conducted on the manufacture of yogurt from milk heated by UHT processes and have compared it with the conventional method. This paper reviews the characteristics of yogurt made from UHT milk, including its apparent viscosity, gel strength, microstructure, syneresis (water-holding capacity) and flavour, as well as the behaviour of yogurt cultures in the UHT-treated pre-mix.

Antibiosis associated to Lactobacillus acidophilus growth .1. Strain selection and study of an alternative medium using whey

The production of antimicrobial compounds of some strains of Lactobacillus acidophilus has been studied. They have been grown in whey supplemented with soy milk. It has been found that the production of compounds is able to inhibit the growing of both target bacteria analysed: Staphylococcus aureus and Escherichia coli. The results showed a significant variation (p>0.05) depending on the strain of L. acidophilus and on the level of supplementation utilized. Most of the inhibition observed resulted from the presence of the lactic acid produced. It has also been found the production of other antimicrobial compounds showing inhibitory capacity. The action of these compounds was influenced by the substract pH.