Ministry of Agriculture and Forestry, National Food Reference Laboratory, Yenimahalle, 06560 Ankara, Turkey.
Institute of Food Safety, Ankara University, Dışkapı, 06110 Ankara, Turkey.
Food Chem. 2020 Oct 1;326:126977. doi: 10.1016/j.foodchem.2020.126977. Epub 2020 May 5.
Changes in sensorial, chemical and microbiological qualities of kefirs fortified with black carrot (KBCJ), black mulberry (KBMJ), pomegranate (KPJ), and strawberry (KSJ) juices at different concentrations (10, 25 and 50%, w/w) were monitored throughout storage at 4 °C for 12 weeks. The most preferred kefirs by the sensorial panel were KSJ and KPJ, followed by KBMJ and KBCJ. KBMJ was associated with the highest anthocyanin stability, followed by KPJ, KSJ, and KBCJ. Lactic acid [r = (-0.688)-(-0.970)], glucose [r = (-0.563)-(-0.793)] and microorganisms [r = (-0.633)-(-0.961)] in kefirs had significant effect on anthocyanin stability and colour (p < 0.05). Copigmentation between lactic acid and anthocyanins were observed. Fortification with 25% juices led to an increase (1.8-4.8 times) in antioxidant activity (AA). Shelf-lives of samples, except for KPJ, ended after 12 weeks of storage, due to low sensorial scores. Additions of SJ, PJ and BMJ at 25% concentration are recommended for the production of more palatable kefir with high AA.
在 4°C 下储存 12 周期间，监测了不同浓度（10%、25%和 50%，w/w）的黑胡萝卜（KBCJ）、黑桑椹（KBMJ）、石榴（KPJ）和草莓（KSJ）汁强化的开菲尔的感官、化学和微生物质量变化。感官小组最喜欢的开菲尔是 KSJ 和 KPJ，其次是 KBMJ 和 KBCJ。KBMJ 与最高的花青素稳定性相关，其次是 KPJ、KSJ 和 KBCJ。开菲尔中的乳酸（r=（-0.688）-（-0.970））、葡萄糖（r=（-0.563）-（-0.793））和微生物（r=（-0.633）-（-0.961））对花青素稳定性和颜色有显著影响（p<0.05）。观察到乳酸与花青素之间的共色作用。25%果汁的强化导致抗氧化活性（AA）增加（1.8-4.8 倍）。除 KPJ 外，所有样品的货架期在储存 12 周后结束，原因是感官评分较低。建议在 25%浓度下添加 SJ、PJ 和 BMJ，以生产更可口、AA 更高的开菲尔。
