Vaquero Cristian, Loira Iris, Raso Javier, Álvarez Ignacio, Delso Carlota, Morata Antonio
enotecUPM, Chemistry and Food Technology Department, ETSIAAB, Universidad Politécnica de Madrid, Avenida Puerta de Hierro 2, 28040 Madrid, Spain.
Tecnología de los Alimentos, Facultad de Veterinaria, Instituto Agroalimentario de Aragón-IA2, Universidad de Zaragoza-CITA, c/Miguel Servet, 177, 50013 Zaragoza, Spain.
Foods. 2021 Jun 25;10(7):1472. doi: 10.3390/foods10071472.
New nonthermal technologies, including pulsed electric fields (PEF), open a new way to generate more natural foods while respecting their organoleptic qualities. PEF can reduce wild yeasts to improve the implantation of other yeasts and generate more desired metabolites. Two PEF treatments were applied; one with an intensity of 5 kV/cm was applied continuously to the must for further colour extraction, and a second treatment only to the must (without skins) after a 24-hour maceration of 17.5 kV/cm intensity, reducing its wild yeast load by up to 2 log CFU/mL, thus comparing the implantation and fermentation of inoculated non- yeasts. In general, those treated with PEF preserved more total esters and formed more anthocyanins, including vitisin A, due to better implantation of the inoculated yeasts. It should be noted that the yeast that had received PEF treatment produced four-fold more lactic acid (3.62 ± 0.84 g/L) than the control of the same yeast, and with PEF produced almost three-fold more 2-phenylethyl acetate than the rest. On the other hand, 3-ethoxy-1-propanol was not observed at the end of the fermentation with a (Td) control but in the Td PEF, it was observed (3.17 ± 0.58 mg/L).
包括脉冲电场(PEF)在内的新型非热技术,为生产更天然的食品开辟了一条新途径,同时又能保留其感官品质。脉冲电场可以减少野生酵母,以促进其他酵母的定植,并产生更多所需的代谢产物。进行了两次脉冲电场处理;一次以5 kV/cm的强度持续施加于葡萄汁以进一步提取色素,另一次在对葡萄汁(不带皮)进行17.5 kV/cm强度的24小时浸渍后施加,将其野生酵母负载量降低了多达2 log CFU/mL,从而比较接种的非酵母的定植和发酵情况。总体而言,由于接种酵母的定植情况更好,经过脉冲电场处理的葡萄汁保留了更多的总酯,并形成了更多的花青素,包括葡萄素A。应当指出的是,经过脉冲电场处理的酵母产生的乳酸(3.62±0.84 g/L)是相同酵母对照组的四倍,并且经过脉冲电场处理产生的乙酸苯乙酯比其他组几乎多三倍。另一方面,在(Td)对照组发酵结束时未检测到3-乙氧基-1-丙醇,但在Td PEF组中检测到了(3.17±0.58 mg/L)。