Greener grass or sour grapes? How people value future goals after initial failure

Across six experiments (N=1,304), people dealt with failure by dismissing the value of future goals. Participants were randomly assigned to receive good or poor feedback on a practice trial of a cognitive test (Studies 1-3, 5-6) or their academic performance (Study 4). Those who received poor (vs. good) feedback predicted that they would feel less happy about a future top performance. However, when all participants received a top score on the actual test they became equally happy, regardless of initial feedback. That is, initial failure made people underestimate how good it would feel to succeed in the future. Inspired by Aesop’s fable of the fox and the grapes, we term this phenomenon the “sour-grape effect”: A systematic tendency to downplay the value of unattainable goals and rewards. Mediation analyses suggest that the low happiness predictions were a self-protective maneuver, indicated by apparent denial of the personal and future relevance of their performance. Moderation analysis showed that people high in achievement motivation constituted the main exception, as they predicted (correctly) that a big improvement would bring them joy. In a final and high-powered experiment, the effect generalized from predicted happiness to predicted pride and gratitude. Crucially, the sour-grape effect was found repeatedly across two different countries (USA and Norway) and multiple settings (lab, field, online), including two pre-registered replications. In line with the principle of "adaptive preferences" from philosophy and cognitive dissonance theory from psychology, the results suggest that what people want is restricted by what they can get.

Alterations on phenolic compounds and antioxidant activity during sour grape juice concentrate processing

The alterations of phenolic compounds and antioxidant capacity of sour grape juice were investigated during the concentration process stages. Phenolics and antioxidant properties of the samples changed more at the vacuum evaporation stage than that of the other stages. After evaporation, the antioxidant capacity of the samples decreased approximately between 14.2 and 17.0 % for DPPH and ABTS methods, respectively. Besides, phenolic contents also decreased approximately as 14.8%. HPLC data on phenolics of sour grape juice during concentrate processing gave 12 polyphenols, including gallic acid, (+)-catechin, (-)-epigallocatechin, vanillic acid, (-)-epigallocatechin gallate, (-)-epicatechin, caftaric acid, caffeic acid and p-coumaric acid, which were determined as 1.05-1.83 mg/100 g, 5.40-7.83 mg/100 g, 6.35-9.21 mg/100 g, 3.01-5.18 mg/100 g, 0- 1.95 mg/100 g, 2.33-3.54 mg/100 g, 12.40-37.60 mg/100 g, 1.44-2.26 mg/100 g and 0.27-0.44 mg/100 g, respectively. Ferulic, sinapic acids and quercetin were only detected at concentrate step of the sour grape juice processing and were found as 0.18 mg/100 g, 0.28 mg/100 g and 0.76 mg/100 g, respectively.