# Flavor Differences of Edible Parts of Grass Carp between Jingpo Lake and Commercial Market
## 1 Introduction  
Grass carp (_Ctenopharnygodon idellus_), typically a freshwater fish, is an important economic freshwater fish in China. In 2020, global carp production was 550 million tonnes, with 21% of the total freshwater aquaculture produced by China [1]. The main edible part of the fish meat provides high nutrient content and is a major contributor to the flavor of grass carp. Generally, the commercial grass carp (CGC) is bred in a high-density culture mode, and microorganisms in the water environment could easily cause the accumulation of undesirable flavors in the fish, thereby affecting consumers' acceptance of cultured grass carp [2]. However, the meat quality of aquatic products, including grass carp, is affected by the different anatomical parts and region of origin, besides the growing environment [3, 4]. Nowadays, wild grass carp is favored by consumers for its excellent sensory characteristics, such as its unique flavor and delicious taste. Jingpo Lake is a lava-dammed lake in China that supports a high abundance of wild grass carp. The lake is a national AAAAA-level tourist attraction in China, popular for sightseeing, and its annual winter fishing festival provides opportunities to sample some authentic local fish dishes. In recent years, wild grass carp from Jingpo Lake (JPGC) has been considered a local specialty. However, few studies have focused on the flavor differences between JPGC and CGC. Flavor, including taste and odors, is an important quality characteristic in evaluating aquatic products. Some previous studies have reported methods for evaluating the non-volatile taste-active compounds in aquatic products, such as free amino acids (FAAs) and nucleotides, and odor-active volatile organic compounds (VOCs), such as alcohols, aldehydes, acids, ketones, esters, and hydrocarbons [5; 6; 7; 8]. Moreover, the human olfactory and taste sensory systems are simulated by the electronic nose (E-nose) and electronic tongue (E-tongue) mechanisms to distinguish aromatic, hydrogen, broad-alcohol, sourness, bitterness, and saltiness, although these electronic sensors cannot detect specific compounds. By contrast, gas chromatography-mass spectrometry (GC-MS) can be used to analyze the specific substances but cannot identify specific tastes and odors. Therefore, several studies used an E-nose to detect the overall odor of foods, solid-phase microextraction (SPME) coupled with GC-MS to analyze the specific compounds [7], E-tongue to detect the overall taste of food, high-performance liquid chromatography to determine the FAAs, and ATP-associated compounds to identify individual taste compounds [9]. Numerous studies have outlined various differences in sensory value between Armed and wild fish, and farmed fish are generally considered less tasty [10; 11; 12; 13]. [PERSON] et al. [14] characterized the difference in nutritional value and flavor among bighead carp raised in the cold-water reservoir (XHK), natural lake (PY), and common culture pond (NC) and found that the strongest fishy odor was detected in cultured walleye; the pleasant plant-like odor was detected in natural lakes and cold-water reservoirs walleye. [PERSON] et al. [15] found that the volatile compounds of largemouth bass cultured in an aquaculture system using a land-based container with recycling water imparted a strong, intense fruity flavor, whereas largemouth bass cultured in a traditional pond system had a strong and pungent flavor. [PERSON] et al. [16] clarified the physical characteristics and volatile matter of muscle of the Yellow River carp (_Cyprinus carpio haematopterus_) grown in the wild, as well as the different farming systems, and found that the best muscle quality and flavor of the Yellow River carp were grown in the wild. However, few studies have examined the flavor differences in different edible parts of grass carp between Jingpo Lake and commercial market.