Abstract Deer apple (Malus trilobata) fruit is present naturally in the Mediterranean region and can be used for many different purposes, such as consuming as fresh and dried fruits, using as herbal tea flavorings, making vinegar, and pickle. Also, it is traditionally used against various health problems like cholesterol, shortness of breath, diabetes, and hypertension. Many researchers have studied some properties of deer apple fruit, such as the ecology of the species, fruit and seed properties, body form, and phenology. In this study, besides pomological properties, the organic acid, phenolic compound, sugar, and aroma composition of the deer apple fruit were determined for the first time. Malic acid (27.5 mg/g) is the most abundant organic acid in deer apple, while fructose (351 mg/g) is the most abundant sugar. It was determined that the deer apple contains various phenolic compounds such as protocatechuic acid, chlorogenic acid, caffeic acid, epicatechin, rutin, and quercetin. Acetic acid, nonanal, hexanal, acetoin, acetaldehyde, n-octanal, hept-2(E)-enal are the most abundant aroma compounds.

Abstract In this study, the effects of frozen storage (for six months at -30 °C) and cooking on total phenolic, antioxidant activity and color characteristics of Polygonum cognatum Meissn. were determined. In addition, the antibacterial activity of the ethanol extract of the plant against Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus, Bacillus subtilis, and B. cereus was investigated. Both frozen storage and cooking have been found to cause significant decreases in the total phenolics. During the storage, differences among DPPH radical scavenging activities were statistically insignificant. However, the DPPH activity has been found to increase significantly with cooking. Copper-reducing antioxidant capacity has started to decrease considerably after four months of storage. Cooking process slightly increased the copper-reducing capacity. Various changes were detected in the color properties of both frozen stored and cooked samples. The ethanol extract of the plant was effective against all the tested bacteria at different ratios.