Orange flour for gluten-free bread

Mar 11, 2013
Orange pomace.

During the processing of fruit and vegetables one third is discarded as 'waste'. The waste or by-product can be described as the core, pips and peel of the fruit or vegetable. This waste can be costly for the manufacturer to dispose of and it may also have hazardous effects on the environment.

Research has shown that a high quantity of nutrients such as dietary fibre and bio-actives are present in these by-products, thus the full potential of the fruit or vegetable is not fulfilled. For example, orange pomace, a by-product from the smoothie and juice industry, has proven to have good nutritional attributes; it is low in fat (2% dry matter) and high in dietary fibre (40% dry matter) and has the potential to be used as a food ingredient.

Researchers at Teagasc Food Research Centre and University College Cork have been looking in to possible uses for this discard, for example, the use of orange flour in gluten-free bread formulations.

Orange flour.

Presently in Ireland, approximately one in a hundred people suffer from coeliac disease. Coeliac disease can be explained as an to the prolamin fraction of the gluten protein, which causes damage to the villi in the . The only treatment for coeliac disease is lifelong avoidance of foods containing wheat, barley, spelt, rye and some oats. Many gluten-free products available on the market are calorie dense, lacking in flavour, mouthfeel and nutrients, and are costly to buy.

Gluten-free formulations

Dr Eimear Gallagher, Teagasc Food Research Centre, explains: "Developing gluten-free formulations can be challenging for the cereal technologist, as the structure-building protein (i.e., gluten) is absent. In the present study, a response surface design was created to statistically calculate the optimal level of orange pomace addition, water addition and ideal proofing time to produce an optimal bread formulation. This study investigated the effects of these three factors in different combinations on bread parameters such as loaf volume, crumb structure, crumb colour, texture, microstructure, nutritional and sensory properties and the optimised samples were assessed using sensory panellists.

"Sensory panellists scored the bread favourably with respect to appearance, flavour, texture and overall acceptability," says Norah O'Shea, a PhD student of Dr Gallagher.

"The inclusion of orange pomace as a novel structure-building and nutritious ingredient in a gluten-free formulation was illustrated in this study. Using response surface methodology as a tool, successfully created bread with favourable baking characteristics and enhanced . pomace proved to be a viable, low cost food by-product for improving the physical and nutritional characteristics of gluten-free breads," explains Dr Gallagher.

"The addition of this ingredient is not limited to gluten-free ; it has potential to be used in both gluten-containing and gluten-free breads and confectionary," adds Dr Gallagher.

Explore further: New technique reveals immune cell motion through variety of tissues

More information: O'Shea, N. et al. (2012). Dietary fibre and phytochemical characteristics of fruit & vegetable by-products & their recent applications as novel ingredients in food products. Innovative Food Science and Emerging Technologies, 16: 1-10.

add to favorites email to friend print save as pdf

Related Stories

Some 'low-gluten' beer contains high levels of gluten

Dec 21, 2011

Beer tested in a new study, including some brands labeled "low-gluten," contains levels of hordein, the form of gluten present in barley, that could cause symptoms in patients with celiac disease (CD), the ...

Going gluten-free: Is the diet a good fit for everyone?

Jun 28, 2012

(Medical Xpress) -- One of the latest trends in the food market and among celebrities is going gluten-free. Snack giant Frito-Lay has announced it will introduce new gluten-free labels and products, and Miley Cyrus has credited ...

Recommended for you

'Global positioning' for molecules

Dec 19, 2014

In everyday life, the global positioning system (GPS) can be employed to reliably determine the momentary location of one en route to the desired destination. Scientists from the Institute of Physical and ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

c0smosis
not rated yet Mar 15, 2013
Fruit peels contain extraordinarily high levels of pesticides. While this might be a step in the right direction, perhaps it needs to be rethought a little bit. At the very least, the raw materials used need to be washed in soapy water.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.