This work attempted to recover high-value substances such as free fatty acids, tocopherols, sterols, and squalene by investigating a supercritical fluid CO 2 (SF CO 2 ) distillation-extraction processing of soybean oil deodorizer distillate. Experimental conditions varied between 50 and 90 °C, at 24.1 and 31.0 MPa. Reverse-phase high-performance liquid chromatography analysis was performed to analyze 14 components in the extracts after SF CO 2 treatment. Experimental results indicated that when tocopherols were extracted at 31.0 MPa, 90 (top) to 70 (bottom) °C, and 1000-L STP CO 2 usage, their recovery reached 83.6% and the average value of the concentration factor was 1.38. Furthermore, the concentration factor of tocopherols grew to 1.70 when the extracts collected in the top exceeded 400-L STP CO 2 . The concentration factors of fatty acids, squalene, and stereols were 1.37, 1.26, and 0.60, respectively. This investigation also found that the percentage of total fatty acids decreased, while polyunsaturated fatty acids increased, with an increase in the CO 2 volume given the same extraction condition.

Supercritical Carbon Dioxide Extraction of High-Value Substances from Soybean Oil Deodorizer Distillate

Deodorizer distillates are waste products of edible oil processing industries obtained during deodorization process of vegetable oils. It is very cheap source of several health beneficial components such as tocopherols, sterols, squalene as well as free fatty acids which have numerous industrial applications. These valuable components are being used in different foods, pharmaceutical formulations and cosmetics. Traditional sources of these useful components are vegetable oils, fruits, vegetables and nuts. Global need of these important components has been exceeded than their availability. The deodorizer distillates of various vegetable oils are considered to be a rich source of several valuable components. Present review will cover brief introduction of common processing stages involved in all vegetable oil processing, analytical methods for characterization of deodorizer distillates by instrumental techniques, importance and commercial value of deodorizer distillates. Future prospective of current field may leads to cost efficient processes and increased attention on the nutritional quality of deodorized oil and commercial applications of deodorizer distillates as well as their valuable components.

Vegetable Oil Deodorizer Distillate : A Rich Source of the Natural Bioactive Components

The enzymatic esterification of free fatty acids from soybean oil deodoriser distillate with ethanol, catalysed by immobilised fungal lipase, was studied. The extent of conversion of free fatty acids to ethyl esters was optimised using a response surface methodology obtained through a second-order factorial experimental design. The variables studied were reaction temperature (30-70°C), enzyme concentration (7-23%) and ethanol/free fatty acid molar ratio (0.3-3.7:1). The optimal reaction conditions achieved were temperature from 46.4 to 53.6°C, enzyme concentration from 13.6 to 16.5% and ethanol/free fatty acid molar ratio from 1.7 to 2.3:1, with conversions above 88%. No significant tocopherol losses were observed during the process. In conclusion, enzymatic fatty acid esterification was shown to be a technically viable process. Le distillat de desodorisation d'huile de soja est un sous-produit valorisable: C'est un melange complexe d'acides gras libres, de sterols et de leurs esters, de tocopherols, de glycerides et d'autres composes. Il est ainsi la matiere premiere principale pour la production de vitamine E. Pour concentrer les tocopherols et le sterol, le procede enzymatique, par une lipase, d'esterification des acides gras presents est plus interessant que le procede chimique. Dans cette etude, les conditions du procede d'esterification enzymatique sont optimisees pour la production d'esters ethyliques par la methode des surfaces de reponses. Les resultats montrent que l'esterification enzymatique des acides gras est un procede techniquement viable.

Optimisation of enzymatic esterification of soybean oil deodoriser distillate

A soybean processing facility, in which refined oil, soy protein concentrate and soy protein isolate are produced, generates residues that if undergo additional industrial operations may result in new products with commercial value. The biorefinery concept is a topic widely discussed by governments, industry, and academics, considering it as a possible path to more sustainable economic development. Total biomass utilization is part of this concept. Therefore, this review aims to present the residues generated during soybean processing, the main composition and possible applications for each one of them, in order to better take advantage of soybean biomass. To do so, first, the process, products and residues were identified using academic material. Next, using Scopus database, a search for each residue was performed and possible applications for it were identified from scientific studies presented in the articles included in this databank. It was verified that, for every residue generated during soybean processing, more than one application was already studied, and they are here presented and discussed. Many interesting opportunities are emerging, such as the use of most of the residues for the production of several types of energy and chemicals that may serve as precursors for the production of many other valuable products, such as lactic acid and nanofibers. The production of enzymes, adsorbents and many other products was also found. However, most studies do not attain to economic or environmental performance of the proposed processes.

Possibilities for Producing Energy, Fuels, and Chemicals from Soybean: A Biorefinery Concept

This experiment was designed to evaluate the effects of selected soybean (SB) processing byproducts (gums, oil, soapstock, weeds/trash) when added back to soybean meal (SBM) during processing on the resulting nutrient composition, protein quality, nutrient digestibility by swine, and true metabolizable energy (TMEn) content and standardized AA digestibility by poultry. To measure ileal DM and nutrient digestibility, pigs were surgically fitted with a T-cannula in the distal ileum. The concentration of TMEn and the standardized AA digestibility by poultry were determined using the precision fed cecectomized rooster assay. Treatments in the swine experiment included SBM with no by-products; SBM with 1% gum; SBM with 3% gum; SBM with 0.5% soapstock; SBM with 1.5% soapstock; SBM with 2% weeds/trash; SBM with a combination of 3% gum, 1.5% soapstock, and 2% weeds/trash; SBM with 5.4% soybean oil; and roasted SB. A 10 x 10 Latin square design was utilized. The experiment was conducted at the University of Illinois, Urbana-Champaign, and at The Ohio State University, Columbus. In the swine experiment, apparent ileal DM, OM, CP, and AA digestibilities were reduced (P < 0.05) when pigs consumed the combination by-product diet compared with the diet containing no by-products. Apparent ileal digestibilities of DM, CP, and total essential, total nonessential, and total AA were lower (P < 0.05) for any diet containing by-products compared with the diet with no by-products. Apparent ileal digestibilities of DM, OM, CP, and AA were lower (P < 0.05) for the roasted SB-compared with the SB oil-containing diet. In the rooster experiment, TMEn values were greater (P < 0.05) for roasted SB compared with SBM with no by-products and increased linearly as the addition of soapstock increased. Individual, total essential, total nonessential, and total AA digestibilities were lower (P < 0.05) for roosters fed roasted SB versus SBM devoid of by-products. Gums, soapstock, and weeds/trash reduce the nutritive value of the resultant meal when they are added back during processing.

Evaluation of the inclusion of soybean oil and soybean processing by-products to soybean meal on nutrient composition and digestibility in swine and poultry

Crude soybean oil contains a number of materials which must be removed to produce a neutral, bland-flavored and light-colored refined oil. While at times these materials may have been considered waste constituting a disposal problem, they are, in fact, valuable byproducts when efficiently recovered and processed. Methods of recovery and processing lecithin, soapstock and deodorizer distillate at the refinery level are reviewed. Process and analytical control are discussed. Some of the important end uses are listed.

J. B. Woerfel

Papers

Processing and utilization of by‐products from soy oil processing