Pittaya Chaikham

Comparison of dynamic viscoelastic and physicochemical properties of pressurised and pasteurised longan juices with xanthan addition

Physical and biochemical properties of pressurised and pasteurised longan juices with various xanthan additions, such as viscoelastic behaviour, colour L (lightness), -a(*) (greenness), b(*) (yellowness), ΔE (total different colours) and BI (Browning Index) parameters, polyphenol oxidase (PPO) activity, ascorbic acid, gallic acid, ellagic acid, total phenols and antioxidant capacity (DPPH assay) were studied. Viscoelastic determination indicated that longan juice with 0.15% xanthan addition was optimal for a fruit drink. Colour parameters showed pressurised longan juice at 500 MPa was brighter and more transparent than fresh and other processed juices. PPO was completely inactivated in pasteurised juices, whereas in pressurised juices at 300 and 500 MPa, the activities were more than 100% and 95-99%, respectively. Bioactive components including ascorbic acid were significantly reduced according to treatment severities, whereas gallic and ellagic acids were relatively stable in all processed juices. Total phenols and DPPH radical-scavenging activity decreased significantly on pasteurisation, but were stable on pressurisation.

Comparison of bioactive components in pressurized and pasteurized longan juices fortified with encapsulated Lactobacillus casei 01

In this study, longan juice was subjected to a high pressure of 500 MPa for 30 min and compared with a juice pasteurized at 90°C/2 min. Probiotic Lactobacillus casei 01 was fortified into both juices and the shelf life of these products was studied. Their bioactive components such as ascorbic acid, gallic acid and ellagic acid were analyzed by High Performance Liquid Chromatography (HPLC). Total phenolic compounds and 2,2-Diphenyl-1-picrythydrazyl radical-scavenging activity were determined by colorimetric and spectrophotometric methods. It was found that the pressurized longan juice retained higher amounts of bioactive compounds than the pasteurized juice. In terms of storage stability, bioactive compounds in both processed juices decreased according to the increase in storage time. The survivability of probiotic L. casei 01 in both processed juices declined from 9 to 6 log CFU/mL after 4 weeks of storage.

Activities of free and encapsulated Lactobacillus acidophilus LA5 or Lactobacillus casei 01 in processed longan juices on exposure to simulated gastrointestinal tract.

BACKGROUND Fruit drinks containing probiotics are gaining interest in the global marketplace. For example, longan juice, containing carbohydrate and various bioactive components, is a potentially health-promoting beverage as well as probiotic carrier for human consumption. In this study, high-pressure and thermal processes were applied to eliminate competitive micro-organisms in longan juice prior to the addition of Lactobacillus acidophilus LA5 or Lactobacillus casei 01. The activities of these probiotics in a simulated gastrointestinal tract were also investigated. RESULTS Encapsulated probiotics could survive in the acidic environment of the stomach and small intestine, while the free cells were completely eliminated. In the colon experiment, the influence of encapsulated L. casei 01 on colon lactobacilli was significantly greater than that of encapsulated L. acidophilus LA5. Both encapsulated probiotics suspended in processed longan juices led to extensive increases in the formation of lactic acid and short-chain fatty acids (SCFA). Acetate was the major SCFA produced by colon bacteria, followed by propionate and butyrate. The discernible clear zone suggested that L. casei 01 provided greater antibacterial activity than L. acidophilus LA5. CONCLUSION Both encapsulated probiotics along with processed longan juice led to significant increases in colon lactobacilli, lactic acid and SCFA formation.

Effects of encapsulated Lactobacillus acidophilus along with pasteurized longan juice on the colon microbiota residing in a dynamic simulator of the human intestinal microbial ecosystem

The effect of encapsulated Lactobacillus acidophilus LA5 along with pasteurized longan juice on the colon microbiota was investigated by applying a dynamic model of the human gastrointestinal tract. Encapsulated L. acidophilus LA5 in pasteurized longan juice or sole encapsulated L. acidophilus LA5 exhibited the efficiency of colonizing the colon and enabling the growth of colon lactobacilli as well as beneficial bifidobacteria but inhibited the growth of fecal coliforms and clostridia. Moreover, these treatments gave rise to a significant increase of lactic acid and short-chain fatty acids such as acetate, propionate, and butyrate. Although acetate displayed the highest quantity, it was likely that after incorporating encapsulated L. acidophilus LA5 plus pasteurized longan juice, quantity of butyrate exceed propionate, and acetate in comparison with their controls. Denaturant gradient gel electrophoresis patterns confirmed that various treatments affected the alteration of microbial community within the simulator of the human intestinal microbial ecosystem.

Efficacy of polymer coating of probiotic beads suspended in pressurized and pasteurized longan juices on the exposure to simulated gastrointestinal environment

Abstract Alginate-coated Lactobacillus acidophilus LA5 or Lactobacillus casei 01 was recoated with either 0.1–0.5% (w/v) alginate or 0.05–0.15% (w/v) poly-L-lysine (PLL) plus 0.2% (w/v) alginate or 5–15% (w/v) gelatin, after which they were determined for survivability in gastric or bile longan juices. The morphology of encapsulated probiotic cells illustrated that recoated beads with 0.5% alginate showed a more compact surface and a greater protective effect than other recoating materials. The recoated beads with 0.5% alginate and 0.05–0.15% PLL plus 0.2% alginate of both strains showed the highest viability in gastric longan juice. In bile longan juice, only 0.5% alginate showed the best protection for both recoated beads. When considering the storage stability, encapsulated L. acidophilus LA5 exhibited a higher viable count than those of the free cells, whereas L. casei 01 showed equivalent viability of both free and double-coated cells. Based on the impact of pressurization or pasteurization, both processed juices gave rise to equivalent survivability of the probiotic cells during storage.

Effect of encapsulated Lactobacillus casei 01 along with pressurized-purple-rice drinks on colonizing the colon in the digestive model.

The objective of the study was to examine the influence of encapsulated Lactobacillus casei 01 combining with two types of pressurized-purple-rice drinks on colonizing the colon using a simulator of the human intestinal microbial ecosystem. Subsequently, the metabolic products of colon bacteria and various microflora were determined. The finding revealed that acetate which was the predominant short-chain fatty acid (SCFA) was found in both proximal and distal colons, while the combination of encapsulated L. casei 01 and germinated-purple-rice drinks gave rise to highest formation of SCFA. Significant impact of rice drinks could be observed on reducing ammonia production. The quantitative polymerase chain reaction analysis demonstrated that encapsulated L. casei 01 and encapsulated L. casei 01 plus rice drinks markedly increased concentration of colon lactobacilli and bifidobacteria by 2 and 1 log 16S rRNA gene copies/mL, respectively. On the contrary, undesirable bacteria such as clostridia and coliforms were significantly reduced with the influence of encapsulated L. casei 01 plus purple-rice drinks.

Physical and chemical properties of Nam Prig Noom, a Thai green-chili paste, following ultra-high pressure and thermal processes

A study of processing green-chili pastes (Nam Prig Noom) by pressurization (100–600 MPa/30–50°C/20 min), pasteurization (90°C/3–5 min) or sterilization (121°C/4 min), subsequently, their physical, biochemical and microbiological qualities as well as the sensory acceptance were assessed. It was found that pressure at low levels (100–300 MPa) could improve activities of enzyme peroxidase (POD), polyphenoloxidase (PPO) and lypoxygenase (LOX) in the chili paste by more than 100%, while pressures above 500 or 300 MPa combined with heat would significantly inactivate these enzyme activities. Both color parameters and enzyme activities illustrated that though some enzymatic browning occurred with the pressurized products indicated by b* (yellowish) parameter, the magnitude of these browning was still milder than those thermally treated products indicated by−a* (greenness) and L (lightness) parameters, presumably as a consequence of the Maillard reaction. Moreover, the sensory scores were found in accordance with color parameters, firmness and capsaicin contents.

Biochemical and Antioxidative Properties of Unprocessed and Sterilized White and Black Sesame By-product from Northern Thailand

The objective of this research was to determine the effects of sterilization on storage stability of white and black sesame by-products. Results showed that sterilization at 120 0C for 10 min had no effect on proximate compositions and mineral contents of both sesame seed cakes, but the significant reductions of thiamine, riboflavin, sesamin, sesamolin, total phenolic compounds and antioxidant capacity (DPPH and FRAP assays) were observed. During the storage at 37 0C, all bioactive components and antioxidant properties apparently tended to decrease when the storage time rose. At the end of storage, PV (peroxide value) and TBARS (thiobarbituric acid-reactive substances) values of stored black sesame seed cakes were shown to be significantly lower than that in white sesame seed cakes. This study may suggest the application of black and white sesame seeds cakes as functional food ingredients in the future production. Current research in Nutrition and Food Science Journal Website:www.foodandnutritionjournal.org ISSN: 2347-467X, Vol. 5, No. (3) 2017, Pg. 196-205 CoNTACT Pittaya Chaikham pittaya.chaikham@gmail.com Faculty of Science and Technology, Phranakhon Si Ayutthaya Rajabhat University, Phranakhon Si Ayutthaya 13000, Thailand

Impact of encapsulated Lactobacillus casei 01 along with pasteurized purple-rice drinks on modulating colon microbiome using a digestive model

Abstract The prospect of Lactobacillus casei 01 and pasteurized purple-rice drinks on modulating colon microbiome by using a simulator of the human intestinal microbial ecosystem was investigated. Accordingly, L. casei 01 alone and with pasteurized purple-rice drink were administered into the proximal and distal colons. In consequence, some colon bacteria and their metabolic activities were examined. The results showed that upon modulating the colon microbiota by L. casei 01 alone with pasteurized germinated-purple-rice drink in the distal colon, acetate and propionate (short-chain fatty acids) were equivalently elevated but other treatments performed differently. Based on the profile of colon microbiota, most treatments stimulated the highest number of lactobacilli followed by bifidobacteria, while other undesirable bacteria were moderately diminished. In overall, larger gelatinized starch in the rice drinks enabled by pasteurization triggered off better modulating impact than by pressurization.