The Chinese Waxberry or Bayberry (Myrica rubra Sieb. et Zucc. Family: Myricaceae) or Yangmei is a small evergreen tree found in much of south-east Asia and China that produces small fruit with the potential to provide excellent colour in product development applications. It also appears to have properties that would make it a part of any antioxidant story and reinforce the healthy benefits of eating fruit.
In China, the fruit is an important produce with production exceeding 300,000 tonnes in the province of Zhejiang alone. It has been known for 7,000 years but started to be cultivated some 2,000 years ago (Chen, 1996). Some of the more important cultivars are cv. Wandao, cv. Biji, cv. Ding-ao and cv. Shuimei. It is usually eaten fresh but one of its main drawbacks has been its very short shelf-life. As a fresh fruit, it decays quickly at ambient temperature, having a shelf-life of just 1 or 2 days (Yang et al., 2009). This reduces its viability as a marketable product. It can be prepared as a sauce, syrup or jam which extends its commercial potential.
The aroma of the fruit has been characterised using gas chromatography-mass spectrometry (GC-MS) coupled with olfactometry (GC-O) (Kang et al., 2012) which is a very powerful method of identifying key aroma compounds. The volatiles were extracted from the fruit using liquid-liquid extraction, solvent-assisted flavour evaporation and headspace solid-phase microextraction (HS-SPME). Differences in aroma profile using principal component analysis (PCA) were characterised. The authors identified the major aroma componentry to be terpenes such as caryophyllene, menthol, 4-terpineol, linalool and linalool oxide. The flavour is said to be acidic and sour.
The major anthocyanin is cyanidin-3-glucoside which amounts to 95% of the available pigment and produces such a vivid red colour in the fruit (Ye et al., 1994; Bao et al., 2005). It possesses a potent polyphenol oxidase (PPO)which has been purified and readily degrades this colour however, but indirectly when gallic acid is added to the pulp (Fang et al., 2007). A method using HPLC (high performance liquid chromatography) coupled to photodiode-array spectrophotometry and electrospray ionization-mass spectrometry (HPLC-PDA-ESI-MS) has been tested on ethyl acetate extracts and four phenolic acids identified – ferulic, caffeic, sinapic and salicylic acids (Wang et al., 2012).
A processing regimen similar to that adopted for blueberries and blackcurrants is suitable. To minimise colour loss from enzymic browning requires either fruit blanching at a pre-pressing stage or pasteurisation of the juice immediately following mashing but before enzyming. Addition of sulphur dioxide to above 50 ppm is also effective, not only in suppressing the PPO (polyphenol oxidase) but also endogenous yeasts.
To maximise the value of colour and other componentry from processed waste, the seed kernels of 5 bayberry cultivars were assessed for their protein and lipid componentry which is high, their amino acid profile and mineral contents (Cheng et al. 2008). The kernels attracted interest because of the possibility of using a waste resource which contained unknown compounds which could induce cell death (apoptosis) or inhibit some stomach cancer cell lines (Zhang et al., 1993). It might also be possible to extract a food-grade oil and some fat-soluble antioxidants from the same source (Zou, 1995).
Extracts of Bayberry have been widely used in Chinese folk medicine for the treatment of gastric intestinal disorders (Chen, 1996), and with benefits in both antimicrobial and antiviral arenas (Xia et al., 2004; Yang et al., 2011). Clearly, this is a fruit which is worth investigating further for its attractiveness in beverage product development.
References
Bao, J., Y. Cai, M. Sun, G. Wang and H. Corke, (2005) Anthocyanins, flavonols, and free radical scavenging activity of Chinese bayberry (Myrica rubra) extracts and their color properties and stability. J. Agric. Food Chem. 53 pp. 2327–2332.
Chen, Z. (1996). The history of bayberries. J. Fruit Sci. 13 pp. 59–61.
Cheng, J., Ye, X., Chen, J., Liu, D., Zhou, S. (2008). Nutritional composition of underutilized bayberry (Myrica rubra Sieb. et Zucc.) kernels. Food Chem. 107(4) pp. 1674–80.
Fang, Z. X., Zhang, M., Sun, Y. F., & Sun, J. C. (2006). How to improve bayberry (Myrica rubra Sieb. et Zucc.) juice colour quality: The effect of juice processing on bayberry anthocyanins and polyphenolics. J. Agric. Food Chem., 54, pp. 99–106.
Fang, Z., Zhang, M., Sun, Y., Sun, J. (2007) Polyphenol oxidase from bayberry (Myrica rubra Sieb. et Zucc.) and its role in anthocyanin degradation. Food Chem. 103(2) pp. 268-273
Fang, Z., Zhang, Y., Lü, Y., Ma, G., Chen, J., Liu, D., Ye, X. (2009) Phenolic compounds and antioxidant capacities of bayberry juices. Food Chem. 113 pp. 884–8.
Kang, W., Li, Y., Jiang, W., Tao,Y. (2012) Characterization of Aroma Compounds in Chinese Bayberry (Myrica rubra Sieb. et Zucc.) by Gas Chromatography mass Spectrometry (GC-MS) and Olfactometry (GC-O). J. Food Sci., 77 (10) C1030- C1035
Wang, C., Zhao, J., Chen, F., Cheng, Y., Guo, A. (2012) Separation, Identification, and Quantitation of Phenolic Acids in Chinese Waxberry (Myrica rubra) Juice by HPLC-PDA-ESI-MS. Publ. Online DOI: 10.1111/j.1750-3841.2011.02563.x accessed 13/02/2012
Xia Q., Chen, J., Wu, D. (2004). Study on scavenging efficacy of phenols extraction of Myrica rubra leaf. Food Sci. 25 pp. 80–3.
Yang, Z., Cao, S., Zheng, Y. (2011) Chinese bayberry fruit extract alleviates oxidative stress and prevents 1,2-dimethylhydrazine-induced aberrant crypt foci development in rat colon carcinogenesis. Food Chem. 125: pp. 701–5.
Yang, Z. F.; Zheng, Y. H.; Cao, S. F. (2009) Effect of high oxygen atmosphere storage on quality, antioxidant enzymes, and DPPH radical scavenging actvity of Chinese bayberry fruit. J. Agric. Food Chem. 57, pp. 176−181.
Ye, X.Q. Chen, J.C. and Su, P. (1994) Identification of the constituent of anthocyanin in Yan-Mei (Myrica rubra cv. Biqi), J. Zhejiang Agricultural Univ. 20(2), pp. 188–190. (in Chinese & translated by colleague 02/03/12).
Zhang, W. M., Wang, L. M., Zhang, S. R., & Xu, J. Y. (1993). A preliminary study on use of red bayberry stones kill or constrain gastric cancer cells. Acta Chinese Medicine and Pharmacology, 3, pp. 38 (in Chinese & translated by colleague 13/09/12).
Zou, Y. H. (1995). Study on the antioxidant ingredients of edible oils in the fruit kernel of Myrica. Chemistry and Industry of Forest Products, 15(2), pp. 13–17 (in Chinese & translated by colleague 08/09/12).
Hello, Just wondered if you had ever thought about our feathered friends in the garden who love berries like this. Over in Oregon, USA, we have a garden which literally just has berries and we have grown nothing else simply to help the robins and other birds through the winter. Worth considering as you discuss food reserves for us humans, I’d like to know more about what these fruits are doing for birds and animals.