浙江2个主栽枇杷品种加工果膏的品质性状比较

为延长枇杷产业链、提高其附加值,对浙江主栽的软条白沙、大红袍枇杷果实进行果膏加工适应性和品质性状比较研究,筛选适宜品种,并研究果浆加酶处理和浓缩程度对该品种果实出汁率,果膏出膏率,总酸、总酚和总黄酮含量,自由基清除能力,色度值和感官评分的影响,确定果膏加工的关键工艺。结果表明,软条白沙枇杷的出汁率为53.18%,出膏率为20.54%,果膏总酸含量为6.70 g·L^-1;大红袍枇杷的出汁率为39.88%,出膏率为15.23%,果膏总酸含量为7.64 g·L^-1,故软条白沙枇杷的加工适应性较好。软条白沙枇杷打浆后加果胶酶和纤维素酶出膏率可提高6.35百分点;果膏中总酚和总黄酮含量、自由基清除能力随可溶性固形物含量增加而提高,从50%浓缩至80%,总酚和总黄酮含量分别提高了242%和211%,1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)和2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), ABTS]自由基清除能力分别提高了1.88、15.26百分点。综合考虑品质性状、产率和节能,建议枇杷果膏加工宜选择软条白沙枇杷为原料,榨汁前加酶处理,将果膏浓缩至可溶性固形物含量为70%。

Comparison on qualitative characters of fruit paste processed using two main loquat varieties cultivated in Zhejiang Province,China

To extend industry chains of loquat Eriobotrya japonica (Thunb.) Lindl] and improve its added value, fruits of two main varieties cultivated in Zhejiang Province (i.e. soft strip Baisha and Dahongpao) were used to compare the process adaptability and qualitative characters of fruit paste to screen suitable variety. The key processes of fruit paste manufactured by the selected variety were determined by investigating the influence of pulp enzymatic treatment and concentrated degree on the juice yield of fruit and yield, total acid contents, total phenols and total flavonoids contents, free radical scavenging abilities, chromaticity values, and sensory scores of the finished fruit paste. The results showed that juice yield and paste yield of strip Baisha loquat were 53.18% and 20.54%, while those of Dahongpao loquat were 39.88% and 15.23%; the total acid content in strip Baisha loquat fruit paste was 6.70 g·L^-1, while that in Dahongpao loquat was 7.64 g·L^-1, so the processing adaptability of soft strip Baisha loquat was better than that of Dahongpao fruit. The treatment of pectinase and cellulase on soft strip Baisha loquat pulp after pulping could increase the paste yield by 6.35 percentage point. The total phenols and total flavonoids contents, free radicals scavenging capacities of loquat fruit paste increased with improved total soluble solids (TSS) contents. When the paste was concentrated from 50% to 80% in TSS, the contents of total phenols and total flavonoids were increased by 242% and 211%, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging capacities were increased by 1.88 and 15.26 percentage point, respectively. Jointly considering qualitative traits result as well as yield and energy-saving views, it was suggested that soft strip Baisha loquat be suitable to process into loquat fruit paste with enzyme treated for pulp before juicing and the juice is concentrated till its TSS content being 70%.