Harratt Ashley, Wu Wenyuan, Strube Peyton, Ceravolo Joseph, Beattie David, Pukala Tara, Krasowska Marta, Blencowe Anton
Applied Chemistry and Translational Biomaterials (ACTB) Group, Centre for Pharmaceutical Innovation (CPI), UniSA Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia.
Future Industries Institute (FII), UniSA Science Technology Engineering and Mathematics (STEM), University of South Australia, Mawson Lakes, SA 5098, Australia.
Foods. 2025 Jul 10;14(14):2438. doi: 10.3390/foods14142438.
Apple pomace, a by-product from the production of concentrated juice, is a major contributor to global food waste. Despite its beneficial nutritional profile, apple pomace is predominantly disposed of in landfills. Rapid fermentation and spoilage caused by microorganisms are compounding factors in this demise, despite significant research into upcycling strategies. Thus, there is an unmet need for economical approaches that allow for the preservation of pomace during storage and transportation to centralized processing facilities from regional hubs. To address this challenge, we investigated the potential of different preservatives for preventing microbial growth and the spoilage of apple pomace, including antimicrobials (natamycin and iodine), polysaccharides (chitosan and fucoidan), and acetic acid. Spread plates for total microbial and fungal counts were employed to assess the effectiveness of the treatments. High concentrations (10,000 ppm) of chitosan were effective at reducing the microbial load and inhibiting growth, and in combination with antimicrobials, eliminated all microbes below detectable levels. Nevertheless, acetic acid at an equivalent concentration to commercial vinegar displayed the highest economic potential. Apple pomace submerged in 0.8 M acetic acid (3 kg pomace per liter) resulted in a five-log reduction in the microbial colony-forming units (CFUs) out to 14 days and prevented fermentation and ethanol production. These results provide a foundation for the short-term storage and preservation of apple pomace that could contribute to its upcycling.
苹果渣是浓缩果汁生产过程中的副产品，是全球食物浪费的主要来源。尽管苹果渣具有有益的营养成分，但主要还是被丢弃在垃圾填埋场。尽管对升级利用策略进行了大量研究，但微生物引起的快速发酵和变质仍是导致其被弃用的复合因素。因此，迫切需要经济可行的方法，以便在从区域中心向集中处理设施储存和运输苹果渣的过程中对其进行保存。为应对这一挑战，我们研究了不同防腐剂对防止苹果渣微生物生长和变质的潜力，包括抗菌剂（纳他霉素和碘）、多糖（壳聚糖和岩藻依聚糖）以及乙酸。采用平板计数法对总微生物和真菌数量进行评估，以确定处理方法的有效性。高浓度（10000 ppm）的壳聚糖能有效降低微生物负荷并抑制其生长，与抗菌剂联合使用时，可将所有微生物数量降至检测水平以下。然而，与商业醋浓度相当的乙酸显示出最高的经济潜力。将苹果渣浸泡在0.8 M乙酸中（每升3千克苹果渣），可使微生物菌落形成单位（CFU）在14天内减少五个对数，并防止发酵和乙醇产生。这些结果为苹果渣的短期储存和保存奠定了基础，有助于其升级利用。
