Viability of Lactobacillus acidophilus La-5 added solely or in co-culture with a yoghurt starter culture and implications on physico-chemical and related properties of Minas fresh cheese during storage

The effect of a probiotic culture of Lactobacillus acidophilus (La-5), added solely or in co-culture with a starter culture of Streptococcus thermophilus, on texture, proteolysis and related properties of Minas fresh cheese during storage at 5 degrees C was investigated. Three cheese-making trials were prepared and produced with no addition of cultures (T1 - control), supplemented with La-5 (T2), and with La-5 + S. thermophilus (T3). Viable counts of La-5 remained above 6.00 log cfu g(-1) during the whole storage for T2, reaching 7.00 log cfu g(-1) on the 14th day. For T3, the counts of La-5 remained above 6.00 log cfu g(-1) after 7 days of storage. Due to the presence of S. thermophilus, T3 presented the highest proteolytic index increase and titratable acidity values. Nevertheless, these results and S. thermophilus addition had no influence on viability of La-5 which presented satisfactory populations for a probiotic food. Moreover, the use of a yoghurt culture for the production of Minas fresh cheese T3 supplemented with La-5 resulted in a good quality product, with a small rate of post-acidification, indicating that traditional yoghurt culture could be employed in co-culture with La-5 to improve the quality of this cheese. (C) 2008 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Influence of Lactobacillus paracasei and inulin on instrumental texture and sensory evaluation of fresh cream cheese

The influence of the addition of a potential probiotic culture of Lactobacillus paracasei and of the prebiotic fiber inulin on the texture profile and on the sensory evaluation of probiotic and synbiotic fresh cream-cheeses was monitored. Three cheese-making trials were prepared in quintuplicate, all supplemented with a Streptococcus thermophilus starter culture (T1, T2 and T3). L. paracasei subsp. paracasei was added to T1 and T2, and inulin, to T2. The instrumental texture profile was determined after 1, 7, 14 and 21 days of storage of the cheeses. Sensory evaluation was performed after 7 days of storage. The presence of Lactobacillus paracasei in cheeses T1 and T2 and of inulin in cheeses T2 did not alter the texture profile significantly. Cheeses T1 were the least preferred in the sensory evaluation and differed signifcantly from T2 and T3, due to acidic taste, according to panelists. On the other hand, T2 was the most preferred one, though not significantly different from T3. The addition of the prebiotic ingredient inulin to fresh cream cheese processed with a potentially probiotic Lactobacillus paracasei strain resulted in a product with appropriate features and with aggregated functional properties.

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.

LACTOBACILLUS ACIDOPHILUS AND BIFIDOBACTERIUM SP IN CO-CULTURE IMPROVE SENSORY ACCEPTANCE OF POTENTIALLY PROBIOTIC PETIT-SUISSE CHEESE

Sensory acceptance of four trials of probiotic petit-suisse cheese was investigated. Cheeses were prepared using Streptococcus thermophilus TA 040 as starter not supplemented with any probiotic culture (T1-control), Lactobacillus acidophilus La-5 (T2), Bifidobacterium animalis subsp. lactis BL04 (T3) and L. acidophilus + B. animalis subsp. lactis (T4). Sensory acceptance tests were performed after 7 and 14 days of storage at 4 +/- 1 degrees C, using a 9-point hedonic scale to evaluate flavour, texture and overall acceptability. The population of La-5 and BL04 remained at 7.0 log CFU g(-1) and at 8.0 log CFU g(-1), respectively, during storage for up to 28 days. After 7 and 14 days of storage, cheese T4 presented the highest sensory acceptance for all attributes evaluated and differed significantly from the other cheeses (P<0.05). After 14 days of storage, cheese T3 presented the lowest acceptance and differed significantly from the other cheeses (P<0.05). The supplementation of petit-suisse cheese T4 with both La-5 and BL04 in co-culture with a starter culture resulted in a product with high probiotic populations during storage and excellent sensory acceptance. The results also showed that, when added separately, La-5 and BL04 did not affect the sensory acceptability of petit-suisse cheese.

Molecular identification of naturally occurring bacteriocinogenic and bacteriocinogenic-like lactic acid bacteria in raw milk and soft cheese

Lactic acid bacteria ( LAB) are currently used by food industries because of their ability to produce metabolites with antimicrobial activity against gram-positive pathogens and spoilage microorganisms. The objectives of this study were to identify naturally occurring bacteriocinogenic or bacteriocinogenic-like LAB in raw milk and soft cheese and to detect the presence of nisin-coding genes in cultures identified as Lactococcus lactis. Lactic acid bacteria cultures were isolated from 389 raw milk and soft cheese samples and were later characterized for the production of antimicrobial substances against Listeria monocytogenes. Of these, 58 (14.9%) LAB cultures were identified as antagonistic; the nature of this antagonistic activity was then characterized via enzymatic tests to confirm the proteinaceous nature of the antimicrobial substances. In addition, 20 of these antagonistic cultures were selected and submitted to genetic sequencing; they were identified as Lactobacillus plantarum (n = 2) and Lactococcus lactis ssp. lactis (n = 18). Nisin genes were identified by polymerase chain reaction in 7 of these cultures. The identified bacteriocinogenic and bacteriocinogenic-like cultures were highly variable concerning the production and activity of antimicrobial substances, even when they were genetically similar. The obtained results indicated the need for molecular and phenotypic methodologies to properly characterize bacteriocinogenic LAB, as well as the potential use of these cultures as tools to provide food safety.

Manufacture of low-sodium Minas fresh cheese: Effect of the partial replacement of sodium chloride with potassium chloride

We investigated the effect of sodium reduction by partial substitution of sodium chloride (NaCl) with potassium chloride (KCl) on the manufacture of Minas fresh cheese during 21 d of refrigerated storage. Four treatments of low-sodium Minas fresh cheese were manufactured, with partial replacement of NaCl by KCl at 0, 25, 50, and 75% (wt/wt), respectively. The cheeses showed differences in the content of moisture, ash, protein, salt, and lipid contents, as well as on the extent of proteolysis and hardness throughout the storage period. However, no difference was observed among treatments within each storage day tested. The partial substitution of NaCl by KCl decreased up to 51.8% the sodium concentration of the cheeses produced. The consumer test indicated that it is possible to manufacture a low-sodium Minas fresh cheese that is acceptable to consumers by partial substitution of NaCl by KCl at 25% (wt/wt) in the salting step.

Effect of inulin and Lactobacillus paracasei on sensory and instrumental texture properties of functional chocolate mousse

BACKGROUND: This study evaluated the effect of a potentially probiotic bacteria (Lactobacillus paracasei subsp. paracasei LBC 82), added solely or together with the prebiotic ingredient inulin on instrumental texture attributes and sensory properties of a functional chocolate mousse during storage at 4 +/- 1 degrees C for up to 28 days. RESULTS: The addition of Lactobacillus paracasei resulted in a firmer and more adhesive chocolate mousse. This effect was intensified with the presence of inulin in the synbiotic formulation (5.24 N and -0.956 N, respectively, for firmness and adhesiveness after 28 days of storage) (P < 0.05). L. paracasei population did not vary (P > 0.05) during storage (always between 7.27 and 7.35 log cfu g(-1)), both for the probiotic and the synbiotic mousses. Synbiotic mousse differed from control and probiotic mousses during storage with respect to the color attribute. Moreover, both probiotic and synbiotic mousses presented taste, aroma and texture perceptions which were different from one another and from the control mousse after 14 and 21 days of storage. CONCLUSION: The use of inulin, together with the potentially probiotic strain of Lactobacillus paracasei subsp. paracasei, is advantageous, conferring potentially symbiotic potential to the chocolate mousse, as well as favorable texture and sensory properties. (c) 2008 Society of Chemical Industry.

Sensory evaluation of probiotic Minas fresh cheese with Lactobacillus acidophilus added solely or in co-culture with a thermophilic starter culture

Sensory acceptance of formulations of probiotic Minas fresh cheese was investigated. Cheeses were prepared and supplemented with Lactobacillus acidophilus (T1 - probiotic), Lactobacillus acidophilus + Streptococcus thermophilus (T2 - probiotic + starter) or produced with no addition of cultures (T3 - control). Sensory acceptance tests were performed after 7 and 14 days of storage at 5 degrees C, using a 9-point hedonic scale (1 = dislike extremely; 9 = like extremely). After 7 days, no significant difference was detected among cheeses T1, T2 and T3 (P > 0.05). After 14 days, cheeses T1 and T2 presented higher acceptance and differed significantly from cheeses T3. Cheeses T3 presented significant difference between 7 and 14 days of storage (P < 0.05), whereas probiotic cheeses T1 and T2 were stable in the same period (P > 0.05). The addition of L. acidophilus, either solely or in co-culture with a thermophilic starter culture, resulted in good acceptance of Minas fresh cheese, improving sensory performance of the product during storage.

Inulin and oligofructose improve sensory quality and increase the probiotic viable count in potentially synbiotic petit-suisse cheese

The influence of inulin, oligofructose and oligosaccharides from honey, combined in different proportions, on the consumers` sensory acceptance, probiotic viable count and fructan content of novel potentially synbiotic petit-suisse cheeses was investigated. Probiotic populations varied from 7.20 up to 7.69 log cfu g(-1) (Bifidobacterium animalis subsp. lactis) and from 6.08 up to 6.99 log cfu g(-1) (Lactobacillus acidophilus). The highest fructan contents were achieved by the cheese trials containing oligofructose and/or inulin (above 8.90 g 100 g(-1)). The control trial showed the lowest mean acceptance (6.63) after 28 days of refrigerated storage, whereas the highest acceptance (7.43) was observed for the trial containing 10 g 100 g(-1) oligofructose. Acceptance increased significantly during storage (P < 0.05) only for cheeses supplemented with oligoftuctose and/or inulin. Cheeses containing honey did not perform well enough compared to the cheeses with addition of inulin and/or oligofructose, and the best synbiotic petit-suisse cheese considering sensory and technological functional features was that containing oligofructose and inulin combined, therefore encouraging the commercial product use. (c) 2007 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Prevalence and characterization of Enterococcus spp. isolated from Brazilian foods

Enterococci can be used in the food industry as starter or probiotic cultures. However, enterococci are also implicated in severe multi-resistant nosocomial infections. In this study, the prevalence of enterococci in selected Brazilian foodstuffs (raw and pasteurized milk, meat products, cheeses and vegetables) was evaluated. Phenotypic and PCR protocols were used for species identification. Tests for production of gelatinase, haemolysin, bacteriocin and bile salt hydrolysis were done with all enterococci isolates, whereas molecular determination of virulence markers (genes esp, gel, ace, as, efaA, hyl and cylA) and antibiotic resistance was checked only for Enterococcus faecium and Enterococcus faecalis isolates. The antibiotic-resistant isolates were assayed for biofilm formation and adhesion to mammalian cells. From the 120 food samples analyzed, 52.5% were positive for enterococci, meat and cheese being the most contaminated. E. faecium was the predominant species, followed by E. faecalis, E. casseliflavus and Enterococcus gallinarum. Phenotypic tests indicated that 67.7% of isolates hydrolyzed bile salts, 15.2% produced bacteriocin, 12.0% were beta-hemolytic and 18.2% produced gelatinase. Antibiotic resistance (gentamicin, tetracycline and erythromycin) and genes encoding for virulence traits were more frequent in E. faecalis than in E. faecium. Three E. faecium isolates were resistant to vancomycin. Among antibiotic-resistant isolates, 72.4% of E. faecalis were able to form biofilm and 13.8% to adhere to Caco-2 cells. Antibiotic-resistant E. faecalis and E. faecium isolates were grouped by RAPD-PCR and a scattered distribution was noted, indicating that resistance was not related to a particular clone. The spread of virulence/resistance traits in isolates of the two species and different RAPD-types suggest the pathogenic potential of both species. By contrast, the recovery of bacteriocinogenic E. faecium isolates with no virulence traits suggests their potential for biotechnological applications. In conclusion, our results showed that enterococci from Brazilian foods present important dualist aspects for food safety. (C) 2008 Elsevier Ltd. All rights reserved.

Nuclear Quadrupole Resonance: A Technique to Control Hydration Processes in the Pharmaceutical Industry

Pharmaceuticals can exist in many solid forms, which can have different physical and chemical properties. These solid forms include polymorphs, solvates, amorphous, and hydrates. Particularly, hydration process can be quite common since pharmaceutical solids can be in contact with water during manufacturing process and can also be exposed to water during storage. In the present work, it is proved that NQR technique is capable of detecting different hydrated forms not only in the pure raw material but also in the final product (tablets), being in this way a useful technique for quality control. This technique was also used to study the dehydration process from pentahydrate to trihydrate.

Warehouse, PNG Coffee Industry Board Office and Warehouse, Goroka

View of exterior wall to warehouse.

Downpipes, PNG Coffee Industry Board Office and Warehouse, Goroka

Detailed view of downpipes and drainage grill.

PNG Coffee Industry Board Office and Warehouse, Goroka

View past tiered amphitheatre and offices above to air strip beyond.

View along western elevation, PNG Coffee Industry Board Office and Warehouse, Goroka

View past timber blinds to balcony and timber sunscreens.