Pectinase treated Apple pomace: An improved medium for xanthan gum production by Xanthomonas campestris

The use of low cost material especially agricultural wastes or by-products of food processing systems is an important factor in decreasing the cost of xanthan gum production. Apple pomace is a by-product of juice extraction and a rich source of nutrients specially pectin. In the previous work we showed that API (Apple Pomace Infusion) is a suitable medium for growth of Xanthomonas campestris. In this lab-scale study, we tried to treat apple pomace with pectinase to increase simple carbohydrates and used it as preculture and production medium in xanthan gum production after sterilization with two different methods of heating and filtration. When pectinase treated Apple pomace (PTAP) was used as preculture and sterilized by membrane filtration, xanthan yield increased for 3 times (as much as YMB) in comparison with not treated API and also showed faster growth rate. In the next step, different concentratios of PTAP (5, 10, 25% w/v) were steam sterilized and used as production medium. Although 25% PTAP gave the highest sugar content, xanthan yield was very low because of non-enzymic browning. However filtered 10% PTAP gave good xanthan yield of 12 g/l, almost as much as YMB. Thus using apple pomace as an inexpensive medium for xanthan gum production is promising.

کلیدواژه ها:

pectinase treated Apple Pomace (PTAP) ، phenolics ، xanthan gum ، Xanthomonas campestris