Morphological, physico-chemical and functional properties of underutilized starches in China Mocang Deng a,1 , Chagam Koteswara Reddy b,1 , Baojun Xu a, ⁎ a Food Science and Technology Program, Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai, Guangdong 519087, China b Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, South Korea abstract article info Article history: Received 11 January 2020 Received in revised form 30 April 2020 Accepted 4 May 2020 Available online 07 May 2020 Keywords: Non-conventional starches Morphology Pasting property In this study, starches were isolated from different non-conventional sources (acorn, black wheat, buckwheat, coix seed, jiaoyu, kuzhu, longya lily, and naked oat) cultivated in China, and their morphological, physico- chemical, and functional properties were analyzed. Among isolated starches, significant differences (p b 0.05) were observed in morphology, pasting, crystallinity, physico-chemical, and functional properties. After a compar- ison with commercial corn starch, all these isolated starches presented promising and unique characteristics. The XRD profile of isolated starches presented A-type (naked oat, buckwheat, coix seed, and black wheat), B-type (longya lily, acorn and jiaoyu) and C-type (kuzhu) polymorphic structures. SEM analysis revealed that the starches isolated from different sources showed distinct shapes exclusively globular, elliptic, and polygonal shapes. The high viscosity of jiaoyu and kuzhu starch pastes can be utilized to have an advantage in instant soups and sauces. Hence, the present study will improve the scientific basis on starches from different non- conventional sources, facilitate their utilization in a variety of applications. © 2020 Elsevier B.V. All rights reserved. 1. Introduction Starch is a semi-crystalline and biodegradable biopolymer, widely used as a gelling, thickening, stabilizing, blending, and coating agent for various food and non-food products [1]. To date, numerous studies have been performed on the isolation, structure, physico-chemical and functional properties of mainstream starches (maize, potato, wheat, and rice), due to their easy accessibility and their extensive usage in a variety of applications [2–5]. Commonly, the starch characteristics iso- lated from different sources differ, primarily in their composition, mo- lecular structure, morphology, and some of functional quality characteristics [6,7]. Furthermore, starch properties have been deter- mined by the starch components, chain length, and the ratio of amylose and amylopectin [7,8]. Besides, starches isolated from different botani- cal sources have been categorized by amylose content and crystalline pattern [9]. To date, the literature covers a little evidence on the isola- tion and properties of starches from non-conventional and underutilized sources cultivated in China. Naked oat (Avena chinensis) is one of the important members of oat species. It is commonly grown and consumed in Mongolia and Northern China and used as a traditional Chinese medicine [10]. Naked oat grains can reduce serum lipids and blood pressure, and controls postprandial blood sugar [11]. As well, starch is the major glycemic carbohydrate component in naked oat grains and accounts for above 60% of the dry matter [12]. Buckwheat (Fagopyrum esculentum L.) is a nonglutinous pseudo-cereal crop, commonly grown in Asian countries and used as a traditional food. Buckwheat is a rich source of starch (60–70%), min- erals, essential amino acids, and phenolic compounds [13,14]. Coix seed is the mature kernel of Coix lachryma jobi L.; it is a perennial herba- ceous plant in the family of Gramineae. It is commonly grown in China, Korea, Thailand, Burma and Japan, as well as is planted in most of the provinces of China [15]. Coix seed is rich in starch (around 61%), protein, polyphenols and trace elements [16]. Longya lily (Lilium browni) be- longs to the genus Lilium of the family; it is widely distributed in Hunan and Jiangxi provinces of China. Longya lily is used as a functional ingredient in Chinese traditional medicine [17]. The bulbs of longya lily comprises a high quantity of starch (around 69%, dry basis) and used in the development of traditional foods [18]. Edible canna (Canna edulis) is a perennial herb, which is commonly known as jiaoyu, and belongs to the family of Cannaceae. It is widely dis- tributed in Asian countries, including China, Thailand, and Vietnam. The rhizome of jiaoyu rich in starch and nutrients and used for the develop- ment of traditional foods [19]. Kuzhu (Castanopsis sclerophylla), a mem- ber of Fagaceae family and is widely cultivated in the south of the Yangtz River of China. Kuzhu fruit is used as a traditional medicine for treating indigestion, diarrhea, and quenching thirst [20]. The acorn is an edible International Journal of Biological Macromolecules 158 (2020) 648–655 ⁎ Corresponding author at: Programme of Food Science and Technology, Beijing Normal University-Hong Kong Baptist University United International College, 2000, Jintong Road, Tangjiawan, Zhuhai, Guangdong 519087, China. E-mail address: baojunxu@uic.edu.hk (B. Xu). 1 Two authors have equal contribution to this paper. https://doi.org/10.1016/j.ijbiomac.2020.05.031 0141-8130/© 2020 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect International Journal of Biological Macromolecules journal homepage: http://www.elsevier.com/locate/ijbiomac