Benucci Ilaria, Lombardelli Claudio, Muganu Massimo, Mazzocchi Caterina, Esti Marco
Department of Agriculture and Forest Sciences (DAFNE), Tuscia University, Via S. Camillo de Lellis snc, 01100 Viterbo, Italy.
Foods. 2022 Jul 28;11(15):2246. doi: 10.3390/foods11152246.
Protein stability in bottled white wine is an essential organoleptic property considered by consumers. In this paper, the effectiveness of an early enzymatic treatment was investigated by adding a food-grade microbial protease at two different stages of winemaking: (i) at cold settling, for a short-term and low temperature (10 °C) action prior to alcoholic fermentation (AF); (ii) at yeast inoculum, for a long-lasting and medium temperature (18 °C) action during AF. The results reveal that protease sufficiently preserved its catalytic activity at both operational conditions: 10 °C (during cold settling) and 18 °C (during AF). Furthermore, protease addition (dosage 50-150 μL/L) raised the alcoholic fermentation rate. The treatment at yeast inoculum (dosage 50 μL/L) had a remarkable effect in preventing haze formation, as revealed by its impact on protein instability and haze-active proteins. This minimally invasive, time and resource-saving enzymatic treatment, integrated into the winemaking process, could produce stable white wine without affecting color quality and phenol content.
瓶装白葡萄酒中的蛋白质稳定性是消费者所考虑的一项重要感官特性。本文通过在酿酒的两个不同阶段添加食品级微生物蛋白酶来研究早期酶处理的效果：（i）在冷沉降阶段，在酒精发酵（AF）之前进行短期低温（10°C）作用；（ii）在酵母接种时，在AF期间进行长期中温（18°C）作用。结果表明，蛋白酶在两种操作条件下（10°C（冷沉降期间）和18°C（AF期间））都充分保留了其催化活性。此外，添加蛋白酶（剂量为50 - 150μL/L）提高了酒精发酵速率。酵母接种时的处理（剂量为50μL/L）对防止浑浊形成有显著效果，这从其对蛋白质不稳定性和浑浊活性蛋白的影响中可以看出。这种微创、节省时间和资源的酶处理方法融入酿酒过程中，可以生产出稳定的白葡萄酒，而不影响颜色质量和酚类含量。
