摘要
主要研究嗜热链球菌发酵乳对全蛋液起泡性的影响。随着发酵乳含量的增加(0%~50%w/w),ST5-24 h发酵乳与全蛋液混合物的黏度逐渐增加(17.9~197.3 m Pa·s),pH值逐渐降低(7.75~4.95);Zeta电位先降低再增加,且在25%左右达到最小值;表面张力整体呈下降趋势。全蛋液与发酵乳混合物的起泡能力在发酵乳含量小于30%时有降低的趋势但变化较小;混合物的泡性稳定性整体呈先上升(38~71 min)后下降(71~30 min)趋势,且在25%时达到最大值71 min(全蛋液的1.9倍)。此外,由泡沫微观结构的变化也可以看出,添加一定量的发酵乳可以增加液膜的弹性,从而显著提高全蛋液的泡沫稳定性。研究发现,在无蔗糖等稳泡剂添加的情况下,发酵乳的添加可以显著增加全蛋液泡沫的稳定性,且在一定量的添加范围内对起泡能力影响不大。
Egg has been extensively used in aerated food because of its functional properties of foaming. This study aimed at investigating the effect of fermented milk cultured for 24 hours with Streptococcus thermophilus （ST5- 24 h fermented milk） on the foaming properties of liquid whole egg. Increasing fermented milk concentration （0% w/ w-50% w/w） gradually increased solution viscosity （17.9 - 197.3 mPa s） and decreased pH values （7.75 -4. 95 ） and the interfacial pressure presented a decrease as a whole. The Zeta values decreased at the earlier and then in- creased, the minimum was reached when the content of fermented milk was about 25%. The foam ability presented a slightly decrease when its concentration was less than 30%. Incorporation of fermented milk enhanced the foam stabil- ity and the half-life of foam drainage increased rapidly from 38 min to 71 min （1.9 times compared to liquid whole egg） at 25% and then decreased to 30 min. Moreover, microstructures at different time indicated that addition of fer- mented milk could possibly improve the bubbles elasticity and the stability of foams. In conclusion, the fermented milk had a significant impact on the foaming properties of liquid whole egg and little impact on the foaming ability without foam stabilizer.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2017年第4期119-124,共6页
Food and Fermentation Industries
关键词
发酵乳
全蛋液
起泡性
黏度
fermented milk
liquid whole egg
foam properties
viscosity
