Enzymatic hydrolysis of oilseeds prior to extraction has recently been shown to enhance the extractable oil in oilseeds and its recovery. This paper presents the results of optimizing the combination of enzymatic hydrolysis with one or more conventional pretreatments to soybean and of optimizing the hydrolysis parameters as they determine the mechanical extractability as well as the solvent extractability. Enzymatic hydrolysis in conjunction with flaking (dehulling inherent) and steam conditioning offered statistically the best pretreament combination for soybean at a 5% level of significance, enhancing the extractable oil content by about 4.8% of moisturefree sample. The optimal hydrolysis parameter values based on response surface analysis were: hydrolysis moisture content 23.22% wet basis, enzyme concentration 11.99 vol/wt, and incubation period 13.79 h. Over 99% of the total extractable oil released after hydrolysis was extractable within 16 h on a Soxhlet extractor. JAOCS 74, 1543-1547 (1997). KEY WORDS:Enzymatic hydrolysis, extraction, hexane extraction, oilseeds pretreatment, soybean, soybean pretreatment.Soybeans are now well established as a major oilseed crop in India, more so because they are a valuable source of proteinrich food as well. Conventionally, soybeans are deoiled by solvent extraction. Mechanical deoiling of soybeans, though not practiced commercially, is possible and has been proposed particularly under Indian conditions (1). Deoiling requires certain pretreatments. These include unit operations like dehulling, splitting, cracking/breaking, grinding or flaking, and cooking or steam conditioning (2). The purpose of pretreatments is to break the seed walls and release the oil for extraction.Enzymatic hydrolysis has recently been shown to be another option for pretreatment. It opens up the cell walls through biodegradation and releases oil, thus serving the same purpose as the conventional pretreatments. In addition, it breaks up the complex lipoprotein and lipopolysaccharide molecules into simpler molecules, releasing extra oil which was otherwise nonextractable. Fullbrook (3) first observed this phenomenon in crude protein isolates from melon seeds and demonstrated its usefulness in ground soybean and rapeseed extraction. Enzymatic hydrolysis was later shown to enhance oil availability and/or recovery in various oilseeds pretreated through different combinations of conventional pretreatments, viz., crushed and autoclaved soybean, sunflower, castor and cottonseeds (4), autoclaved canola flakes and seeds (5,6), broken soybean seed (7,8), soyflakes (8), soybean grits (9), and sunflower kernel halves (9). Further, enzymatic hydrolysis was shown to reduce the extraction time by Sosulski et al. (5) in canola flakes and by Kashyap et al. (8) in soyflakes and broken soybean seeds. Better oil recovery from mechanical deoiling of broken soybean seeds has been demonstrated by Smith et al. (7) using enzymatic hydrolysis. However, use of one or more conventional pretreatments along with the enzymatic...

Purpose The purpose of this paper is to discuss the relevance and evolution of adaptive markets hypothesis (AMH) that has gained traction in the recent years, as it provides a dynamic perspective to the concept of informational efficiency. Design/methodology/approach This paper discusses several issues related to the concept of informationally efficient markets that have indicated efficient market hypothesis to be an incomplete portrayal of stock market behavior. Findings The authors find that a strict and perpetual adherence to informational efficiency is highly unlikely, and AMH provides a much more plausible description of the behavior of stock markets. Originality/value The authors provide a description of studies that examine the testable implications of AMH.

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