To solve the difficulty of storing and transporting yak butter, yak butter microcapsule powders were prepared using a mixture of maltodextrin and sodium caseinate as the wall material, a mixture of molecular distilled monoglycerides and sucrose ester as the emulsifier and guar gum as the stabilizer by vacuum freeze-drying or spray drying. The basic physicochemical properties (moisture content, solubility, rheology, surface oil content, encapsulation efficiency, and yield), microscopic structure, and thermal stability of the two as-prepared samples were compared. The results showed that the microencapsulated powders prepared by the two methods were milky white in color and free of impurities, and had a fresh aroma. Both of them exhibited high encapsulation efficiency, (90.17 ± 1.07)% and (92.12 ± 0.32)%, respectively. The yield of freeze-dried microcapsule powders, (98.42 ± 0.38)%, was significantly higher than that of spray-dried microcapsule powders, (25.77 ± 1.34)%, and the average particle size (D[4,3] = 16.695 μm) was smaller than that of spray-dried powder (D[4,3] = 24.945 μm). The solubility and fluidity of the spray-dried powder were superior to those of the freeze-dried powder. Under a scanning electron microscope (SEM), the surface of spray-dried powder was smooth and spherical in shape, while the freeze-dried powder was irregular. The thermal stability of the spray-dried powder was better. In summary, when considering economic benefits, the spray-dried powder holds greater significance for industrial production.

Yak milk is a characteristic resource in the Qinghai-Tibet Plateau of China. It has incomparable characteristics with other milks and has the potential to be developed into high-quality dairy products. In recent years, intensive research efforts have been made to investigate yak milk, but the development and utilization of yak dairy products in China is not perfect yet. This paper summarizes the latest progress in the development of processed yak milk products such as fermented milk, Qula, whey, cheese and butter, aiming to clarify the existing framework system of yak milk processing, find out the potential research directions and develop new yak dairy products. It is expected to provide scientific reference for the further development and utilization of yak milk resources and promoting economic development in the Qinghai-Tibet Plateau.

The effect of microwave power, irradiation time and temperature on the detoxification efficiency of linseed meal was addressed by one-factor-at-a-time and orthogonal array design methods. Further, the effect of fermentation time, starter culture concentration and fermentation temperature on the content of cyanide in yogurt with added detoxified linseed meal was investigated by one-factor-at-a-time and orthogonal array design methods. The results showed that the optimum detoxification conditions that provided the lowest cyanide content of linseed meal of 14.02 mg/kg were as follows: microwave irradiation time 60 s, microwave power 640 W, and temperature 70 ℃. The optimum fermentation conditions that provided the lowest cyanide content of yogurt with added detoxified linseed meal of 8.45 mg/kg were as follows: fermentation time 9 h, fermentation temperature 41 ℃, and starter culture concentration 1.50 g/100 mL. In conclusion, yogurt fermentation could further reduce the cyanide content in flaxseed meal.

In recent years, consumers have shown a rising demand for a healthy and nutritious diet, and cheese has become a new favorite of Chinese consumers because of its good nutritional and health-promoting characteristics. In 2005, the sales and import volume of cheese in China increased by 27.08% and 27.4% year-on-year compared with those in 2016, respectively. China’s cheese market size has maintained an upward trend. At present, the production of cheese in China is mainly concentrated in Xinjiang, Tibet and other ethnic minority areas, where different ethnic groups use sheep milk, yak milk or buffalo milk to produce cheese according to their own living habits and regional characteristics. However, the production of these ethnic cheeses have not been standardized and industrialized, resulting in high production cost. In addition, the quality is highly variable and the taste is generally poor. Therefore, improvements should be made according to the market demands.