Medical Affairs and Innovation, Héma-Québec, Québec, QC, Canada.
J Pediatr Gastroenterol Nutr. 2021 May 1;72(5):756-762. doi: 10.1097/MPG.0000000000003065.
This project aims at comparing the impact of Holder pasteurization (HoP) and high-pressure processing (HPP) on bacterial load and retention of immunological components in human milk.
Human milk samples discarded by the Public Mothers' milk bank (Montreal, Canada) for bacterial purpose were pooled (n = 6) and pasteurized either by heating in a water bath (62.5°C, 30 minutes) or by HPP treatment (425 MPa, four cycles of 6 minutes, initial milk temperature of 4°C or 37°C). Bacterial load, lysozyme activity, and levels of immunoglobulins, lactoferrin, lipase, and 26 cytokines were analyzed. Untreated milk samples from same pools served as control.
HPP treatment of milk allows a similar elimination of bacteria than HoP; bacterial counts were under the detection limit [<3 colony-forming units (CFU)/mL] in 50% of milk pools after HPP treatment, compared to 17% for HoP. With initial heating of samples to 37°C before HPP treatment, inactivation to an extent under the detection limit was reached in 67% of pools. There is no significant difference in IgA, lysozyme, and cytokines concentrations between untreated milk and all treatment methods. While no significant difference was observed in the amount of lipase (P > 0.07) and IgG (P > 0.11) between untreated milk and HPP-treated milk samples, HoP seems to be damaging for these factors (P < 0.04). IgM is well preserved in HPP-4°C samples compared to untreated milk (P = 0.07) whereas a decrease is observed for this immunoglobulin levels in HPP-37°C and HoP samples (P < 0.01). Lactoferrin activity, is well maintained in HPP-37°C milk samples in comparison to untreated milk samples (P = 0.52). A decrease in activity of this molecule is noted for samples treated with HPP at 4°C (P = 0.02) and this decrease is even more pronounced for HoP samples (P = 0.004).
HPP is a promising alternative to HoP for treatment of human milk intended to preterm babies. Our results demonstrate that HPP treatment of human milk provides safe milk with less detrimental effects on the biochemically and immunologically active milk components than HoP.
本项目旨在比较Holder 巴氏消毒法（HoP）和高压处理（HPP）对母乳中细菌负荷和免疫成分保留的影响。
从蒙特利尔公共母乳银行（加拿大）丢弃的母乳样本（n=6）用于 pooled，并通过水浴加热（62.5°C，30 分钟）或 HPP 处理（425 MPa，4 个周期 6 分钟，初始牛奶温度为 4°C 或 37°C）进行巴氏消毒。分析细菌负荷、溶菌酶活性以及免疫球蛋白、乳铁蛋白、脂肪酶和 26 种细胞因子的水平。来自同一 pool 的未经处理的牛奶样本作为对照。
与 HoP 相比，HPP 处理的牛奶可达到类似的杀菌效果；在 HPP 处理后，50%的牛奶 pool 中细菌计数低于检测限（<3 菌落形成单位（CFU）/mL），而 HoP 处理的则为 17%。在 HPP 处理前将样品初始加热至 37°C，67%的 pool 可达到检测限以下的失活程度。未经处理的牛奶与所有处理方法之间的 IgA、溶菌酶和细胞因子浓度无显著差异。未经处理的牛奶与 HPP 处理的牛奶样本之间的脂肪酶量（P>0.07）和 IgG（P>0.11）无显著差异，但 HoP 似乎对这些因素造成损害（P<0.04）。与未经处理的牛奶相比，HPP-4°C 样品中的 IgM 得到很好的保存（P=0.07），而 HPP-37°C 和 HoP 样品中的这种免疫球蛋白水平下降（P<0.01）。与未经处理的牛奶样本相比，HPP-37°C 牛奶样本中的乳铁蛋白活性得到很好的维持（P=0.52）。HPP 处理的 4°C 牛奶样本中观察到该分子活性下降（P=0.02），而 HoP 样品中的下降更为明显（P=0.004）。
HPP 是替代 HoP 用于治疗早产儿母乳的有前途的方法。我们的结果表明，与 HoP 相比，HPP 处理母乳可提供安全的牛奶，对生物化学和免疫活性牛奶成分的不利影响较小。
