The overall objectives of food processing are to promote the consumption of staple and new crops, to increase the value of agricultural products, and to enhance the development of agro-industry. Research focuses on the development of food processing technology and the production of healthy foods, using special crops, citruses, legumes, and tropical fruits as raw materials. Various processing methods, such as fermentation, extraction, concentration, dehydration, and fining, have been used to produce innovative food products that meet consumers’ need and preference.

● Supercritical carbon dioxide fluid extraction and LC-MS technologies

　Advances have been made in developing healthy products. Flavonoids, known to show high physiological activities, were successfully extracted from the rinds of Citrus depressa Hayata and Citrus mitis Blanco using a supercritical carbon dioxide fluid extraction technology. The extracts can be used in the production of different types of healthy foods. The technology of supercritical carbon dioxide fluid extraction has also been applied for extracting pumpkin seed oil and bitter melon seed oil, both are good sources of unsaturated fatty acids. Another technology, liquid chromatography/tandem mass spectrometry (LC-MS), was used to identify 31 flavonoids in the Citrus mitis Blanco rind and 13 phenolics in Penghu Fongru herb. With the ability of characterizing unknown compounds, the LC-MS technique can be used as a rapid selection tool for identifying special crops that have the potential of becoming natural he althy products.

     
       The Citrus depressa Hayata product              The pumpkin seed product made using
         made using the supercritical carbon                 the supercritical carbon dioxide fluid
          dioxide fluid extraction technology                            extraction technology

● A wide range of healthy food products

　Several processed products have been developed using legumes and fruits as ingredients. Adzuki natto, containing higher amounts of antioxidants and lower amounts of purine than soybean natto, was developed by inoculating Bacillus subtilis natto on Adzuki bean grains. To increase the output values of pineapple and plum, new fruit vinegar beverages were developed following a modified method of using pure then mixed strains of bacteria for alcohol fermentation and acetic acid fermentation.

　The leaves of guava are rich in flavonoids (rutin, kaempferol, quercetin, etc). The flavonoids have been reported to be effective in reducing blood glucose level. Efforts have been put into screening of varieties that can provide higher anti-bacterial activity and more flavonoids contents. Guava leaf tea, supplied in a tea bag form, is manufactured using a processing technique designed to preserve the flavonoids.

　The drying processing techniquefor Indian jujube was successfully developed. The dried candied jujube is a seedless and low-sugar product with no unpleasant odor. The dried jujube can be stored at room temperature without the addition of preservatives. It is a good snack food with a chewy texture appropriate for consumers of all ages.

　Vacuum concentrationis a dominant method for preparing lemon juice in the current food industry in Taiwan. However, nutrients, colors, and flavors deteriorate due to the long processing time in the vacuum concentration conditions (i.e. heating at 40~50℃). We invented a combined concentration technique to solve the challenge. This new technique prevents the deterioration of most of the functional ingredients (Vitamin C and polyphenols) as well as the flavors and colors in the 5 times concentrated lemon juice.

　Submerged vinegar fermentationis an energy-saving procedure (meets global carbon reduction trends) that requires longer processing time and provides more aroma and flavor compounds compared to fast fermentation for industrial vinegar. We have successfully developed a pineapple vinegar fermentation technique through Industry-University Collaboration Projects to provide a new health and safety fruit juice vinegar for consumers. This submerged fermentation technique has been transferred to the industry in 2012. The product produced by our submerged fermentation is high in nutrients and has a rich and unique flavor. The development of the submerged fermentation technique for producing various fruit vinegar beverages will creates new avenues for farmers.

     
                      Adzuki bean natto                                           Pineapple vinegar drink

     
                      Guava leaf tea                                            Candied Jujube Products

       
                Diluted, reconstituted, and                       Homemade concentrated lemon juice 
                concentrated lemon juice