Effect of sulfur fumigation on the nutritional quality of dry lily (Lilium davidii Duch) bulb

corresponding

TAO GUO, LI-YANG WEI, TONG-TONG SONG, DONG WANG, JIAN-PING MA, YA WANG*, AI-HONG ZHAO
*Corresponding author 
School of Life and Engineering, Lanzhou University of Technology Langongping Street 287, Lanzhou 730050, China

Abstract

The study evaluated the effect of sulfur fumigation (SF) on nutritional quality of dry lily bulb with non-treatment and blanching dry bulbs as controls. The results showed that SF treatment can decrease reducing sugar content, total sugar content and some kinds of amino acids such as alanine and arginine in comparison to the non-treatment dry bulbs, and also reduce the pH value with a SF dose-dependent manner. Moreover, SF treatment can slightly increase total amino acids contents, and improve the contents of part of amino acids content to some extent such as cystine. While, Free amino acids contents of all SF dry bulbs hadn’t significant change after SF. Compared to blanching dry bulbs, the SF ones showed more complex change of amino acids. All of these results confirmed that the SF had a significant impact on the nutritional quality of lily.


INTRODUCTION

The genus Lilium consists of approximately 100 species, and China is the diversity center of wild Lilium in the world (1). Lily (Lilium L.) is an edible, medicinal and ornamental plant. There are about 39 species in China, mainly distributing in southwest and central China (2), and there are four producing area for cultivation lily in China including Lanzhou, Yixing, Shaoyang and Huzhou. Among which, Lilium davidii Duch in Lanzhou producing area is thought to be a high-quality variety because of its hypertrophy bulbs, sweet taste and less fiber, and it is the only sweet lily in China (3).

Dry lily is the most main way of consumption for lily products (4). Sulfur fumigation (SF) was often used in Chinese herbs and agricultural products drying process due to its sterilization and bleaching effects, and the sulphur-fumigated products often have a better appearance and longer shelf life (5). SF is a traditional processing method of edible lily. The appearance of sulphur-fumigated lily is very attractive, and extremely superior to ones of lily products using the other processing method. However, the met ...