Tate & Lyle was the standout gainer on the FTSE 250 after Liberum upgraded the stock to 'buy' from 'sell' and lifted its price target to 670p from 505p.
"While history is disappointing - four profit warnings and a collapse of around 40% in pre-tax profits since full-year 2014 - we see early signs of change and scope for significant upside," it said.
Liberum said the key question is whether management's strategy can deliver visible, sustainable earnings growth beyond FY17.
In order to determine the potential, it benchmarked Tate's operations with US-based Ingredion, which is the group's closest peer. It said the results are reassuring.
"As we suspected, many facets of Tate's operations compare favourably to Ingredion. In our view, Tate's historical difficulties are grounded in execution and strategic ambition, areas that management is working to address."
Liberum upgraded ASOS to 'buy' from 'hold', saying three things have changed its view of the stock.
Firstly, it believes that the investment in infrastructure coming on stream should drive operating leverage over the next few years.
Secondly, it pointed to the recent sharp fall in the shares
and said this tilts the risk/reward balance back towards reward. It noted the shares have dropped 39% since their April 2015 highs, meaning they now trade at a 16% discount to the long-term price-to-earnings average.
Finally, Liberum said that with easing comps over the next few reporting periods, it expects the company to report strong sales growth, which has historically been the main driver of the share price.
Premier Farnell was under pressure after Citigroup downgraded the stock to 'sell' from 'neutral' and cut its price target to 90p from 140p following the company's profit warning last week.
The bank said it was downgrading its full-year 2016 earnings before interest and amortisation estimate to £74m, in line with management guidance, which implies a 20% contraction in second-half EBITA year-on-year.
Citi said that given uncertainty over its ability to deliver sales growth and operating leverage, earnings risk remains on the downside as management struggles to offset ongoing gross margin erosion.