Comparison of Biochemical Changes in Kefirs Produced from Organic and Conventional Milk at Different Inoculation Rates of Kefir Grains

Abstract

The purpose of this study was to assess effects of milk variety (organic and conventional) and the inoculation rate (0.2 g 100 g -1 and 0.5 g 100 g ) and benzene-containing components (0.066 g kg -1) were higher in conventional milk kefi r than those (9.54 g kg , respectively) in organic milk kefi r. Increase in inoculation rate of kefi r grains was directly proportional to increases in succinic and lactic acids, VOCs acetaldehyde, ethanol, ethyl acetate, benzene derivatives, free fatty acids C 4 , C 6 and total FAAs especially proline, tyrosine, cysteine and valine amino acids. As a result, the most biochemical changes in kefi r samples showed considerably differences depending on the both inoculation rate of grains and milk origin, and panelists liked kefi r made from organic milk with 0.2% inoculation rate as grains due to probably the low lactic acid (6.43 g kg ) and the high carbohydrate (54.84 g kg -1 ) concentrations.

Chemical, Microbiological, and Functional Characterization of Kefir Produced from Cow’s Milk and Soy Milk

“…e total free amino acid concentration for cow's milk kefir differs between the reports. Total free amino acids in this study were 20.92 mg 100 mL −1 , but three previous reports described variable concentrations from 7 to 76 mg 100 mL −1 [29][30][31]. is difference could arise from a combination of factors such as proteolytic activity, assimilation, and release from the cells [32].…”

“…It has also been reported that the nutritional composition of kefir is influenced by milk type, fermentation conditions, kefir grain origin, and storage conditions [4]. e composition of major free amino acids differs between this and other studies [29][30][31], with the variability likely arising from the aforementioned factors. A significant concentration of Glu was detected in both cow's milk and soy milk kefir in our study, indicating that these beverages could have rich umami-related amino acid properties.…”

Kefir Tanesi ve Yoğurt Kültürü ile Organik Sütten Üretilen Süzme Süt Ürününün Soğuk Depolanması Sırasında Kimyasal Değişimler

“…1. Organic cow milk is used for strained product manufacturing since kefir grains display a good activity in organic milk compared with conventional milk also organic milk kefir is more aromatic [15]. Kefir grains were inoculated at the rate of 0.2 g/100 g milk to organic cow milk at 25°C.…”

Çilek ve Kayısı Aromalı Kefirlerin Depolanması Sırasında Mikrobiyolojik Özelliklerindeki Değişim

“…ve 10 5 kob/g düzeyinde asetik asit bakterileri (Acetobacter sp. gibi) bulunmaktadır [4,5,9,10,11]. Bu nedenle, kefir, laktik asit ve maya fermantasyonu ile karakterize edilir [3].…”

“…Geleneksel kefirin tat ve aroması, kefir tanesinin doğal starter kültürleri olan simbiyotik metabolik aktiviteye sahip çok sayıda bakteri ve mayadan kaynaklanır [6,11]. Bu mikroorganizmaların faaliyeti sonucu kefirde hem laktik asit ve hem de alkol fermantasyonu bir arada gerçekleşir.…”