slight differences are observed between citric acid – Ca lactate
combination treatments frozen directly and after cooling for
overnight. Adhering 0.4% citric acid in Ca lactate dips prefreezing
treatments lead to relative improvement in quality
indices, where drip loss reduced by 61–132% relative to
untreated and by around 12–19% compared to Ca lactate
treatments and by around 44–105% for 0.4% citric acid treatment
while firmness raised by around 34–69%, 14–18% and
39–64% for untreated, Ca lactate and 0.4% citric acid treatments,
respectively. A considerable reduction in browning
index was also observed. The retention of both ascorbic acid
and anthocyanin content was noticeably increased by 46–
57% and 34–37% compared to untreated and by around 25–
27% and 21–31% relative to Ca lactate treatments and by
around 21–37% and 3–8% for 0.04% citric acid treatment,
respectively. In a study on improving quality of home frozen
strawberries, Hudson et al. (1975) added calcium lactate,
ascorbic acid, citric acid and tartaric acid alone or in combination
to a 60 (w/V) sugar syrup held in storage for up to
3 months. Citric acid gave the best color and overall rating
whereas calcium lactate and ascorbic acid improved firmness,
suggesting that combinations might be best (see Fig. 2).