Free fatty acid profiles of fermented beverages made from ewe’s milk

Abstract

-The aim of the present study was to estimate the level of the free fatty acids (FFA) in fermented beverages (yogurt, bioyogurt, sour milk and kefir) made from ewe's milk. Identification and quantification of FFA were performed by gas chromatography. It was found that FFA content in the fermented beverages was significantly affected by the kind of starter culture. Yogurt, as well as bioyogurt, possessed more lauric, myristic, palmitic, stearic and oleic acids than kefir and sour milk. The inverse trend was found for acetic acid level. In the beverages produced using mesophilic cultures the amount of this compound was higher than in beverages containing thermophilic bacteria. Due to the fact that acetic acid was predominant among FFA, the highest total FFA was found for kefir and sour milk. It was also observed that the amount of most of the FFA on the last day of the storage period was lower than on the first day of analysis. Résumé -Profils des acides gras libres dans les laits fermentés au lait de brebis. Le but de la présente étude était d'estimer le niveau des acides gras libres (AGL) dans des boissons fermentées (yaourt, bioyogourt, lait caillé et kéfir) au lait de brebis. L'identification et la quantification de AGL ont été réalisées par chromatographie en phase gazeuse. On a constaté que le type de ferment lactique affectait de manière significative le contenu en AGL dans les boissons fermentées. Le yaourt aussi bien que le bioyogourt présentait une quantité plus importante d'acides laurique, myristique, palmitique, stéarique et oléique que le kéfir et le lait caillé. La tendance inverse a été trouvée pour le niveau d'acide acétique. Dans les boissons qui ont été produites en utilisant la culture mésophile, la quantité de ce composé était plus élevée que dans les boissons qui contenaient les bactéries thermophiles. Étant donné que l'acide acétique était prédominant parmi les AGL, la quantité la plus importante d'AGL a été trouvée pour le kéfir et le lait caillé. On a également observé que la plupart des AGL était trouvée en plus faible quantité le dernier jour de la période de stockage par rapport au premier jour de l'analyse.

Evaluation of volatile compounds and free fatty acids in set types yogurts made of ewes’, goats’ milk and their mixture using two different commercial starter cultures during refrigerated storage

“…No specific changes in free fatty acids C 4 and C 6 were observed at 7 and 14 days of storage whereas a maximum level was reached at day 21. Similar results were obtained by other researchers (Bonczar et al, 2002;Reguła, 2007). Increase in volatile free fatty acids (C 4 -C 8 ) may be related to the increase in activity of L. delbrueckii subsp.…”

“…This could be attributed to high tetradecanoic acid content in ewes' milk in comparison with goats' milk, which was observed by others (Kondyli & Katsiari, 2001;Kondyli & Katsiari, 2002). MCFFAs (C 10 -C 12 ) levels of the yogurts were significantly (P < 0.05) affected by storage time, which was similar to the finding of Reguła (2007) for ewes' yogurt.…”

“…Similar results were obtained in previous studies (Rašić & Vučurović , 1973;Regula, 2007). Both medium-(C 10 -C 14 ) and long-(C 16 -C 18:1 ) chain free fatty acids in this study were slightly lower than results obtained by Reguła (2007). Long-chain free fatty acids showed an opposite relationship with short chain free fatty acids C 4 -C 8 during storage.…”

Kualitas Kimia, Fisik Dan Sensori Kefir Susu Kambing Yang Disimpan Pada Suhu Dan Lama Penyimpanan Berbeda

“…Terjadi peningkatan kadar FFA dalam kefir selama penyimpanan dan bertambahnya temperatur penyimpanan (Reguła, 2007) (-5)). Faktor-faktor yang mempengaruhi viskositas pada curd kefir dihasilkan oleh BAL dalam memfermentasi susu menyebabkan viskositas meningkat.…”

Patterns of survival and volatile metabolites of selected Lactobacillus strains during long-term incubation in milk

“…The greatest differences were observed between the L. crispatus L800 which was producing the highest amount of that acid, and the L. acidophilus K55/81 and L. acidophilus 2B strains, which were generating concentrations of acetic acid accounted for 98.1 and 289.7 Pg/ml, respectively. The presence of acetic acid in cultured milk is likely to result from the hydrolysis of saccharides coupled with transformations of pyruvate (Reguãa, 2007). The production of acetic acid is determined by the presence of oxygen in the medium, while the acetaldehyde may be formed alternatively in the same pathway under anaerobic conditions (Fernandez-Mugara et al, 1998).…”