Encapsulated black garlic: Comparison with black garlic extract in terms of physicochemical properties, biological activities, production efficiency and storage stability

Abstract

In this paper, the convenience of encapsulation technique was investigated in terms of characterization of capsule, changing the volatile compounds and preservation biological activity throughout six months for black garlic (BG) by comparison with the aqueous extract which prepared from BG (stored at 4 °C) each analysis period. Besides, the genotoxic and antigenotoxic aspects of aqueous black garlic extract (BGE) and black garlic capsule (BGC) developed as a novel promising product were also researched. The S-allyl-L-cysteine (SAC) content, which is mostly known to be responsible for biological activity, was preserved in BGC during six months. The variety of volatile compound of BGC (2 compounds) was significantly reduced compared to BG (17 compounds) and BGE (7 compounds), which indicates that the extraction and encapsulation traps the undesirable odor. A significant decrease was observed for total phenolic content and antioxidant capacity (performed with DPPH and CUPric Reducing Antioxidant Capacity (CUPRAC)) of BGC with storage like BGE. In contrast, the values obtained with the ABTS method remained constant with storage. The antimicrobial activity (carried out on five Gram-positive bacteria, three Gram-negative bacteria and three yeasts) of BGC was preserved better than BGE. The treatment concentrations (50, 100, 200 μg/mL) of both BGE and BGC did not have a genotoxic effect and moreover they have antigenotoxic effects against mitomycin C on human lymphocyte cells. All these results implied that BGC can be good a candidate to increase the consumption of BG providing health benefits and functional supplement for food.