The Study Of The Pollen Mead

Honey with abundant of nutritious value and high economical value, is a sweetening agent with health-care function. Pollen also has full of nutrients. So pollen mead can be obtained by yeast's fermenting the mixture of honey and pollen, with honey as the main ingredient. Now there are many studies on wine both in and out of China, but we haven't seen a report on pollen mead. So this paper was made a study on it. First the yeast was mutated by ultraviolet ray, and the pertinent capability of yeast was measured. A research on breaking the pollen wall was made and a suitable method for breaking the pollen wall was found, and the rate of wall-broken was counted. Then a study on the fermentation of pollen mead was made and the optimum fermentation conditions were obtained. Capillary electrophoresis chromatography was used to analyze the kinds and contents of amino acids in the mead and to find a suitable method for breaking the pollen wall, and the relative physical and chemical marks of pollen mead in the process of fermentation were surveyed. The sensory evaluation and microbial marks of pollen mead were determined. Finally the aroma components of mead were analyzed by GC-MS. All the experiments were provided in a view to theoretical foundation and scientific basis for further study of pollen mead.The results are as follows:1. A initial strain was got by a series of purification of wine yeast. Several numbers of mutant yeast strains, obtained from the initial strain by UV irradiating for different time and different distance, were screened. Then a survey on the pertinent capability of mutant strain was determined. The results showed that the optimum mutant conditions were the irradiating dosage of 15 w, the irradiating distance of 20 cm and the irradiating time of 60 s.2. Capillary electrophoresis chromatography was used to analyze the kinds and contents of amino acids in the pollen mead and to analyze a suitable method for breaking the pollen wall. In the period of active fermentation, 0.5% rape pollen whose wall was broken by the temperature fluctuation was added into the fermented honey. After 10 days of the period of main fermentation, the pollen mead produced in this way was rich in amino acids with good quality.3. This test used several different methods for breaking the rape pollen wall: ultrasonic method, enzyme based method, and temperature fluctuation. The haemacytometer was used to count the rate of wall-breaking of pollen, and the morphologic changes of the wall-broken pollen were observed under the light microscope. We found that temperature fluctuation had the highest wall-breaking rate of pollen, and the rate was high to 74.3%.4. In order to get the optimum fermenting conditions, a study on pollen mead was made. The results showed that: with honey as the main ingredient, adding water into the honey to adjust the initial sugar concentration of 20%, and adding the nutrient salts of 0.25g/L MgCl2 and 0.25g/L CaCl2 , the SO2 addition was 90 mg/ L, the inoculation of yeast was 9%, the fermenting temperature was 25℃, in the period of growing abundantly and lively of the fermentation, 0.5% rape pollen whose wall was broken by the temperature fluctuation was added into the fermented honey, after 10 days of the period of main fermentation, the pollen mead with high quality can be obtained.5. Aroma components in the pollen mead were extracted by solvent extraction. According to the analysis of gas chromatography/mass spectrometry, 12 peaks were separated and 7 components were identified. The main components were phenethyl alcohol, ethyl caproate, n-decanoic acid, 4-hydroxy phenethyl alcohol, 3,7,11-Trimethyl-2,6,10-dodecatrien-1-ol, 7-anisyl-2,2,4,8-tetramethyltricyclo undecane, 1,2-Benzenedicarboxylic acid-2-Methyl- propyl ester.