Development of a whey-based beverage with enhanced levels of conjugated linoleic acid (CLA) as facilitated by endogenous walnut lipase

In this study, optimization of fermentation conditions, and applying endogenous walnut lipase were investigated for the manufacture of a fermented, whey-based beverage containing conjugated linoleic acid (CLA). Among different commercial starter and probiotic cultures, the culture containing Lactobacillus delbrueckii subsp. bul-garicus and Streptococcus thermophilus showed high potency for CLA synthesis. The fermentation time and the type of walnut oil (lipolyzed or non-lipolyzed) had significant effects on CLA production, as the highest CLA content (36 mg/g fat) was synthesized in the sample containing 1 % lipolyzed walnut oil fermented at 42 degrees C for 24 h. Moreover, fermentation time had the highest contribution on viable cell counts, proteolysis, DPPH scav-enging activity, and final pH. A significant and positive correlation between cell counts and CLA content was also observed (r = +0.823, p < 0.05). This study establishes a cost effective approach for converting cheese whey to a value added beverage enriched with CLA.

Automated summary

This study investigated the optimization of fermentation conditions and the use of endogenous walnut lipase for the production of a whey-based beverage enriched with conjugated linoleic acid (CLA). Among different commercial starter and probiotic cultures, the combination of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus showed the highest potential for CLA synthesis. The fermentation time and the type of walnut oil used had significant effects on the production of CLA, with the highest content synthesized in the sample fermented with 1% lipolyzed walnut oil at 42 degrees C for 24 h. This study presents a cost-effective approach for converting cheese whey into a value-added beverage enriched with CLA.