Mohammad Reza Edalatian Dovom; Mohammad Bagher Habibi Najafi; Seyed Ali Mortazavi; Majid Hashemi; Masoud Yavarmanesh
Abstract
The objective of this study was to evaluate lactic flora identification in fresh (one-day) and ripened (90-day) Koozeh cheese samples as one of the raw milk cheeses. In first step, in order to isolate the different genera of Lactic acid bacteria (LAB), selective and differential (corresponding) media ...
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The objective of this study was to evaluate lactic flora identification in fresh (one-day) and ripened (90-day) Koozeh cheese samples as one of the raw milk cheeses. In first step, in order to isolate the different genera of Lactic acid bacteria (LAB), selective and differential (corresponding) media were used as follow: MRS for lactobacilli and pediococci, MRS+ vancomycin for leuconostocs, M17 for lactococci and KAA for enterococci. Totally, 48 single, purified colonies were selected and identified using confirmatory, biochemical and phenotypic tests down to the genus level. Lactobacilli (33.33%), lactococci (12.5%), pediococci (2.08%), enterococci (47.91%) and aerococci (4.16%) were determined as the most abundant genera. At last, carbohydrate fermentation profile using API 50 CH and API 20 STREP kits was used for identification down to species level. Finally, following species were identified: Lactobacillus. plantarum, Lb. brevis, Lb. lindneri, Lb. helveticus, Lb. delbrueckii ssp. delbrueckii, Lb. pentosus, Lb. fermentum, Lactococcus. lactis ssp. lactis, Enterococcus. faecium, Ent. faecalis, Ent. avium, Ent. durans and Aerococcus. viridans. In fresh cheese, the Lactococci and lactobacilli genera were predominant but in ripened cheese the enterococci replaced them. Predominant species in fresh cheese were as follow: Lac. lactis ssp. lactis (44.44%) and Lb. plantarum (22.22%) but Ent. faecium (43.58%), Lb. brevis (12.82%) and Ent. faecalis (7.69%) constituted the major part in ripened cheese. We can mention that these predominant lactic acid bacteria play an important role during ripening and also flavor production in raw milk cheeses like Koozeh. So, more precise identification is very necessary using culture- based molecular and culture- independent methods down to strain level.
Fereshteh Hosseini; Mohammad Bagher Habibi Najafi; Majid Hashemi; Shadi Bolourian; Fereshteh Zaman Zade
Abstract
Macaroni is one of the favorite dishes in Iranian,s family food program. In this study, effects of using different level of curcumin as a natural and functional component extracted from Curcuma Longa plant, against total count , total coliforms, psychrotrophic bacteria, yeasts and moulds and colorimetric ...
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Macaroni is one of the favorite dishes in Iranian,s family food program. In this study, effects of using different level of curcumin as a natural and functional component extracted from Curcuma Longa plant, against total count , total coliforms, psychrotrophic bacteria, yeasts and moulds and colorimetric properties of macaroni in comparison with beta carotene and turmeric as commercial color additives has been investigated. Treatments were five different level of curcumin, C1:0/005, C2:0/01, C3:0/03, C4:0/05, C5:0/07, 0/07 turmeric and 0/01 beta carotene as positive controls and sample with no color additive as a negative control. PCA, VRBA and MEA mediums were used for microbial analysis. Colorimetric properties of macaroni in two form (powdered and non powdered ) was measured with a Hunter Lab Colorimeter and the color differences were recorded as CIE-LAB L*(lightness), a* (redness–greenness) and b* (yellowness–blueness) values and the colorimetric difference (ΔE) for each sample was calculated. Results showed that there is a linear relationship between %curcumin and total count, yeasts and moulds, so with increasing curcumin level in samples, total count, yeasts and moulds were decreased. Also, samples containing curcumin in comparison with the samples containing the same percent of beta carotene were lighter, less red and have the same yellowness. In fact, using %0/03 curcumin in macaroni formulation, produces the same ΔE as %0/07 turmeric and %0/01 beta carotene in comparison with non color additive samples. Also, by increasing the amount of curcumin in formulation, macaroni were being less light, redder and more yellow.
Keywords: Macaroni, Curcumin, Antimicrobial, Hunterlab, Turmeric
