Fresh-keeping effects of three types of modified atmosphere packaging of pine-mushrooms

Highlights

• Five pine-mushroom storage stages were advised according to the sensory dynamics.

• Texture changes and browning were most efficiently delayed by PE packaging.

• Tissue senescence was most efficiently delayed by PE and PVC packaging.

• Odor changes were most efficiently delayed by SW packaging.

• Water vapor and gas transmission properties of packaging affect sensory dynamics.

Abstract

Pine-mushrooms are one of the most prized mushrooms. They are difficult to store. Modified atmosphere packaging has been widely used in mushroom storage, but few reports are associated with pine-mushrooms. The effects of polyvinyl chloride (PVC), silicon windows (SW) and polyethylene (PE) packaging materials on the sensory of texture, senescence, browning and odor changes have been evaluated and the preliminary mechanisms have been studied. Texture changes were most efficiently delayed by PE as a result of the lowest respiration rates and weight loss. Senescence was most efficiently delayed by PE and PVC as a result of the raised CAT activities and ascorbic acid contents. Browning was most efficiently delayed by PE as a result of the decreased PPO activities. Odor changes were most efficiently delayed by SW, the decreased ammonia contents may be important reason. Different water vapor and gas transmission properties of packaging may determine the different pine-mushroom sensory.

Introduction

Pine-mushrooms (Tricholoma matsutake Sing.) are one of the most prized mushroom species and still remain wild and can't be cultivated (Murata et al., 2015). Pine-mushrooms are commonly found in northeast Asia, southwestern China and parts of central and northern Europe (Endo et al., 2015). In oriental countries, pine-mushrooms have long been consumed either raw or cooked as a top-grade food for their abundant aroma and flavor (Cho et al., 2010, Cho et al., 2006b). Pine-mushrooms have also been used as traditional Chinese medicine for the prevention and treatment of diseases for several thousands of years (Ishihara et al., 2003, Yang et al., 2009). Recently, polysaccharides isolated from pine-mushrooms have been proven to have antimicrobiological, antioxidant, antitumor and immune activities (Ding et al., 2010, Li et al., 2015, You et al., 2013). Because of the nutritional and delicious features of T. matsutake, the prices are inflated up to 50–400 USD/kg according to their grades (Lim et al., 2007). The data from China Customs show that the annual exported sales of pine-mushrooms in China were estimated at 5.9 × 10⁹ USD (Data, 2015).

Although pine-mushrooms are favored and expensive, they are very difficult to store. They lose edibility in 1–2 days at ambient temperature because of their thin epidermal structure, high respiration rate and high moisture content, features also observed in other wild mushrooms (Mahajan et al., 2008). Even at low temperatures, aroma and edible qualities of pine mushrooms decreased fast and deteriorate in about 10 days in general. In China, the separate origins (rural mountain area in the southwest) and markets (coastal city in the east or overseas) further create new conflicts related to the short storage life.

MAP has been widely used for the storage of mushrooms such as Lactarius deliciosus, Lentinus edodes, Lentinus edodes and Pleurotus florida, but there are few studies associated with T. matsutake (Andrés et al., 2014, Jafri et al., 2013, Li et al., 2014). Different MAP packaging materials, such as PVC, PE and PP, modulate different transmission rates of water vapor, CO₂ and O₂, MAP controls the respiration rate of mushrooms, thus preserving the quality and extending the storage time of mushrooms. Because of the diversity of mushroom’s physiological characteristics, appropriate materials must be designed to keep suitable O₂ and CO₂ level and maintain proper humidity (Montanez et al., 2010).

The objectives of this work are to compare the fresh keeping effects of three MAP materials (PVC, SW and PE) and investigate the relation between separate quality traits (texture, senescence, browning, odors) and the packaging features in pine mushrooms under 2 °C.