Browsing by Author "Mamaril, Eden F."

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    Instability of nata formation by Acetobacter acetisubsp. xylinumand a new nata-producing isolate using seaweed pulp extract
    (DMMMSU, 2017-12-01) Mamaril, Eden F.; Galvez, Gerry N.
    A total of nine(9) isolates from nata starter/ mother liquor and five (5) isolates from fresh seaweed pulp extract (SPE) were isolated and screened for ability to produce/ form nata pellicle in glucose-yeast extract (GYE), Hassid and barker broth(HBB) and coconut water media (CWM). The best isolates EM23 from SPE and EFM from nata starter/ mother liquor proved to be stable in producing nata up to 4thtransfer in sterile and up to 2ndtransfer in non-sterile seaweed pulp extract medium (PEM).Contaminants significantly affected the formation of nata. Nata yields and total plate counts of the isolates decreased with increased total bacterial and yeast counts. Yeast species formed films on the surface of fermenting medium thus competed with the nata organisms for both space and oxygen. Contaminants were identified to be Candida, Saccharomyces, Acetobacter, Bacillus, Leuconostocand Pediococcus. The buildup of these contaminants was accompanied with increases in pH and alcohol levels and increase in total acidity of the medium.
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    Nata formation using Averrhoa bilimbi (Kamias) fruit juice as substrate
    (Don Mariano Marcos Memorial State University – South La Union Campus, 2011-03) Abarcar, Alvin E.; Mamaril, Eden F.; Villanueva, Prescilita M.; Calicdan, Theresa R.; Aspiras , Ofelia E.; Peralta, Tessie Q.
    Growth conditions for nata formation using kamias fruit juice as substrate for the nata producing organism Acetobacter aceti subsp. xylinum were determined. Thickness (mm) and weight (mg) were monitored on nata formed using five (5) amounts of inoculum, four (4) juice concentration, six (6) pH levels and five (5) amounts of sugar. Nata formed in the culture substrate after 10-day incubation at room temperature were sensorily evaluated as raw and cooked samples. The thickest and heaviest nata was formed in 25% juice concentration with 25% inoculum. Thickness and weight of nata increase with increase in the amount of inoculum from 5%-25% in 25% juice concentration. The thickest nata was likewise formed in substrates with 12% and 14% sugar at pH 4.5 and 5.0. Significant interactions were reflected among pH level and amount of sugar on the weight of nata. Acceptability of raw nata was generally perceived to be "slightly better than nata de coco. Likewise, the cooked nata was perceived to be "much better" than the reference sample-nata de coco.
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    Screening and characterization of agar of selected Agarophytes of La Union
    (DMMMSU, 2017-12-01) Mamaril, Eden F.
    Agars of five (5) agarophytes of Balaoan and three (3) agarophytes of Sto. Tomas, La Union were screened and characterized based on yield (%), gelling and melting temperatures (°C), gel strength (g/cm2), rupture force (g), cohesiveness (g)and sulfate content (%). Agars of Balaoan agarophytes significantly differed in all physico-chemical properties considered. Gelling temperature, gel strength, rupture force, cohesiveness and sulfate content significantly differed among Sto. Tomas agarophytes. Agars of Gelidiella acerosa of both sources were comparable in terms of yield melting temperature and sulfate content. Likewise, agars of G. coronopifolia were comparable in yield, gelling and melting temperatures, gel strength, rupture force, cohesiveness and sulfate content. Relationships existed among the physicochemical properties ranged from negative weak to positive strong.