Effects of co-fermentation and sequential malolactic fermentation on antioxidant activities and phenolic components of red-fleshed apple cider

Abstract

Red-fleshed apple (Malus niedzwetzkyana dieck) was used as the fermentation material, and the fermentation mode of red-fleshed apple cider was studied by using alcohol fermentation as control (CK), simultaneous malolactic fermentation (SIM) and sequential MLF (SEQ). The main chemical parameters, antioxidant activities and sensory quality were analyzed to evaluate the quality of red-fleshed apple cider. Compared with the cider without lactic acid bacteria, the total phenolics contents (TPC) and total anthocyanins contents (TAC) in MLF apple cider were significantly decreased, while the total flavonoids content (TFC) were significantly increased. Among them, the TPC and TAC in apple cider obtained by SIM were the highest, while the TFC in apple cider obtained by SEQ. In addition, compared with the control group, the pH of cider obtained by SEQ and SIM was significantly increased by about 0.25 units, while the total acidity was significantly decreased. Therefore the taste of cider obtained from SIM and SEQ were significantly improved, and the cider obtained by SIM got the highest score by sensory analysis, which scored the highest for floral and fruitiness notes. These results indicated that SIM was an effective way to produce red-fleshed apple cider.