Lignin - An underutilized, renewable and valuable material for food industry.

Lignin is the second most abundant biorenewable polymers only next to cellulose and is ubiquitous in various plant foods. In food industry, lignin often presented as a major component of by-products from plant foods. In the last decade, the food and nutritional interests of lignin attracted more and more attentions and great progresses have been accomplished. In the present review, the structure, physicochemical properties, dietary occurrence and preparation methods of lignin from food resources were summarized. Then, the versatile activities of food lignin were introduced under the subtitles of antioxidant, antimicrobial, antiviral, antidiabetic and other activities. Finally, the potential applications of food lignin were proposed as a food bioactive ingredient, an improver of food package films and a novel material in fabricating drug delivery vehicles and contaminant passivators. Hopefully, this review could bring new insights in exploiting lignin from nutrition- and food-directed views.