Physicochemical and sensory characteristics of sheep kefir during storage

• Autorzy: Cais-Sokolinska D. , Dankow R. , Pikul J.

Warianty tytułu

PL

Charakterystyka cech fizykochemicznych i sensorycznych kefiru owczego podczas jego przechowywania

• Języki publikacji: EN

Abstrakty

EN

The aim of the study was physicochemical and sensory characterization of kefir manufactured from sheep milk following its production and storage at refrigerated conditions. Sheep milk inoculated with different starter cultures was incubated at the temperature of 23°C (culture DA) and 26°C (culture DC) for the period of 16-18 h until it reached pH of 4.6. The obtained kefir was assessed on the basis of: the extent of its acidification, the content of taste and smell substances and the results of sensory evaluation. The initial titratable acidity of the kefir manufactured with the assistance of the DA culture reached 48.2°SH and was by 14% higher than that of the kefir manufactured with the DC culture. After 21 days of storage, the titrable acidity of the kefir was by 6.5°SH higher in comparison with the values obtained directly after its manufacture. With the passage of storage time, the amount of free fatty acids (FFA) in the examined kefir samples increased significantly. Higher quantities of FFA were found in the kefir with the DA culture than with the DC culture. Kefir obtained with the assistance of the DA culture contained less acetaldehyde and diacetyl directly after manufacture. The quantities of these compounds underwent significant changes during storage. Kefirs manufactured using the DC cultures were more desirable from the sensory point of view than those manufactured using the DA culture. Irrespective of the applied starter culture, the highest overall acceptability scores were awarded to the kefir on the 7th day of storage.

PL

Celem pracy była charakterystyka fizykochemiczna i sensoryczna kefiru wytworzonego z mleka owczego, po jego wyprodukowaniu i przechowywaniu w warunkach chłodniczych. Mleko owcze zaszczepione różnymi kulturami starterowymi inkubowano w temp. 23°C (kultura DA) i w temp. 26°C (kultura DC) przez okres 16-18 h do momentu uzyskania pH = 4,6. Wytworzony kefir oceniono na podstawie stopnia jego ukwaszenia, zawartości substancji smakowo-zapachowych oraz wyników oceny sensorycznej. Początkowa kwasowość miareczkowa kefiru wytworzonego z udziałem kultury DA wyniosła 48.2°SH i była o 14% większa niż kefiru wytworzonego z kulturą DC. Po 21 dniach przechowywania kwasowość miareczkowa kefiru była o 6.5°SH większa w porównaniu z wartościami uzyskanymi bezpośrednio po jego wytworzeniu. Wraz z upływem czasu przechowywania istotnie wzrosła ilość wolnych kwasów tłuszczowych (FFA, free fatty acid) w badanych próbach kefiru. Więcej FFA oznaczono w kefirze z kulturą DA niż z kulturą DC. Kefir otrzymany na bazie kultury DA bezpośrednio po wytworzeniu zawierał mniej aldehydu octowego i diacetylu. Ilość tych związków podczas przechowywania ulegała istotnym zmianom. Bardziej pożądanymi sensorycznie były kefiry wytworzone z kulturą DC niż DA. Niezależnie od rodzaju użytej kultury starterowej najwyższe oceny ogólnej pożądalności uzyskał kefir w 7 dniu przechowywania.

Słowa kluczowe

EN

sheep milk; kefir; physicochemical parameter; sensory characteristics; storage; sensory analysis; starter culture; temperature; pH; acidification; storage time; free fatty acid; quality

• Wydawca: -
• Czasopismo: Acta Scientiarum Polonorum. Technologia Alimentaria
• Rocznik: 2008
• Tom: 07
• Numer: 2
• Opis fizyczny: p.63-73,fig.,ref.

Twórcy

autor

Cais-Sokolinska D.

• University of Life Sciences in Poznan, Wojska Polskiego 31, 60-624 Poznan, Poland

autor

Dankow R.

autor

Pikul J.

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