CN112210103A - 一种食品包装膜及其制备方法 - Google Patents
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Abstract
本发明涉及一种食品包装膜及其制备方法,该食品包装膜由kappa型卡拉胶与改性刺槐豆胶作为凝胶剂成分,与成膜剂、助凝剂和增塑剂共同制备而得,改善了天然刺槐豆胶作为凝胶成分在成膜过程中粘度大、不易除泡、交联时间长等缺陷,本发明的食品包装膜成膜厚度易控制,膜的机械强度和弹性好、阻水性高,同时具有保鲜效果。
Description
技术领域
本发明属于食品包装领域,具体涉及一种食品包装膜及其制备方法。
技术背景
食用包装膜通常是由可食用性物质包括蛋白质、脂质类、多糖类、纤维衍生物以及淀粉等一种或者多种物质为基质,通过交联形成大分子网状结构并具有生物可降解性的薄膜,与传统人工合成聚合物作为包装材料相比,基于天然生物基质材料能够快速降解,减轻环境污染,并可对食品增加其特有营养和风味等优势。
kappa型卡拉胶作为一种凝胶性能极好的生物成膜材料被广泛的在食品日用品等领域,其具有金属钾离子的高敏感性,使得泌水性增大,且其形成凝胶后刚性较大,凝胶易碎,因此通常需与其他多糖进行复配以改善其机械性能。天然刺槐豆胶与kappa型卡拉胶有较好复配效果,形成的凝胶弹性好,可降低单一kappa型卡拉胶形成的脆性凝胶,但由于其分子量大,水溶液粘度高,水不溶物较多,成膜后容易吸水,阻水性能差,影响其在食品功能产品中的应用,使用范围和储存条件局限性大。
发明内容
为了解决以上的不足,本发明的一个目的在于提供一种kappa型卡拉胶-改性刺槐豆胶作为凝胶剂成分;本发明的另一个目的在于提供一种食品包装膜及其制备方法,提高了食品包装膜的机械性能、阻水性和保鲜效果。
本发明提供一种食品包装膜及其制备方法,所述的食品包装膜由成膜剂、凝胶剂、助凝剂和增塑剂组成;
所述的成膜剂为羟丙甲纤维素、羧甲基纤维素、羟丙基淀粉中的一种或组合;
所述的凝胶剂为kappa型卡拉胶-改性刺槐豆胶;
所述的助凝剂为氯化钾、柠檬酸钾、山梨酸钾中的一种或组合;
所述的增塑剂为甘油、聚乙二醇(PEG200、PEG400)中的一种或组合;
所述的改性刺槐豆胶结构式如(I)所示:
所述的改性刺槐豆胶的制备步骤为:
1.0~10g天然刺槐豆胶溶于50~100mL异丙醇溶液中,并加入20~50mL20%(w/w)的NaOH溶液,然后放入室温的水浴锅中磁力搅拌2h,加入1.0~10g季铵盐搅拌均匀,调节pH=8,50~80℃下继续搅拌6~10h,反应结束后将得到的溶液倒入含有20~50mL35%(w/w)HCl的甲醇100~500mL中,抽滤得到沉淀物,用甲醇水溶液洗涤沉淀物并过滤,减压下干燥得到。
所述的食品包装膜的制备步骤为:
将0.2~0.5g助凝剂加入至90~150mL蒸馏水中磁力搅拌溶解,凝胶剂和成膜剂以1:3~1:7添加量比加入并搅拌分散均匀,逐渐加热升温至80~90℃,保温1.0h,使胶液充分溶胀,待用;将0.2~0.5g的增塑剂加入至10~50mL蒸馏水中,磁力搅拌加热并保持80~90℃,过滤,将滤液加入至待用胶液中磁力搅拌混合均匀,采用真空脱气装置对其进行高温脱气、除泡0.5h,降温至50~60℃,静置24h,让胶液进一步交联;将5g交联好的胶液倒置在50~60℃平板(10×12cm)模具上用另一块干净的平板模具进行压板,使胶液均匀平铺于模具上,置于25℃、30%RH恒温干燥箱中,干燥2~4h后,脱模,即可。
其中凝胶剂与成膜剂添加量比优选为1:5。
与现有技术相比,本发明具有如下有益效果:
(1)本发明通过kappa型卡拉胶-改性刺槐豆胶作为凝胶剂组成部分,膜的拉伸强度、断裂伸长率提高了10~50%;
(2)本发明一种食品包装膜的阻水系数可达0.0852g·mm·m-2·h-1·kPa-1,延长猪肉保鲜时间。
附图说明
图1为一种食品包装膜实物图。
具体实施方式
为使本发明的目的、技术方案和优点更加清楚明了,下面结合具体实施方式,对本发明进一步详细说明。应该理解,这些描述只是示例性的,而并非要限制本发明的范围。此外,在以下说明中,省略了对公知结构和技术的描述,以避免不必要地混淆本发明的概念。
实施例1
将0.2g助凝剂加入至100mL蒸馏水中磁力搅拌溶解,凝胶剂和成膜剂以1:3~1:7添加量比加入并搅拌分散均匀,逐渐加热升温至80~90℃,保温1.0h,使胶液充分溶胀,待用;将0.2g的增塑剂加入至10mL蒸馏水中,磁力搅拌加热并保持80~90℃,过滤,将滤液加入待用胶液中磁力搅拌混合均匀,采用真空脱气装置对其进行高温脱气、除泡0.5h,降温至50~60℃,静置24h,让胶液进一步交联,将5g交联好的胶液倒置在50~60℃平板(10×12cm)模具上用另一块干净的平板模具进行压板,使胶液均匀平铺于模具上,置于25℃、30%RH恒温干燥箱中,干燥2~4h后,脱模,即可。
其中凝胶剂与成膜剂的投料比如表1所示:
表1为凝胶剂与成膜剂的投料比
实施例2空白组
将0.2g助凝剂加入至100mL蒸馏水中磁力搅拌溶解,凝胶剂和成膜剂以1:5添加量比加入并搅拌分散均匀,逐渐加热升温至80~90℃,保温1.0h,使胶液充分溶胀,待用;将0.2g的增塑剂加入至10mL蒸馏水中,磁力搅拌加热并保持80~90℃,过滤,将滤液加入至待用胶液中磁力搅拌混合均匀,采用真空脱气装置对其进行高温脱气、除泡0.5h,降温至50~60℃,静置24h,让胶液进一步交联;将5g交联好的胶液倒置在50~60℃平板(10×12cm)模具上用另一块干净的平板模具进行压板,使胶液均匀平铺于模具上,置于25℃、30%RH恒温干燥箱中,干燥2~4h后,脱模,即可。
实施例中成分说明:
所述的成膜剂为羟丙甲纤维素、羧甲基纤维素、羟丙基淀粉中的一种或组合;
所述的凝胶剂为kappa型卡拉胶-改性刺槐豆胶;
所述的助凝剂为氯化钾、柠檬酸钾、山梨酸钾中的一种或组合;
所述的增塑剂为甘油、聚乙二醇(PEG200、PEG400)中的一种或组合。
实施例3
食品包装膜性能考察方法:经由实施例1和2得到的食用包装膜厚度控制在0.12±0.02mm(GB6673-2001),薄膜拉伸性能测定(GB13022-91)、阻水性能WVP(GB1037-1988)和保鲜效果(观察膜包裹的猪肉在4℃下30天内色泽的变化,0~10分代表色泽度加深)。
上述实施例1和2样品理化性质考察结果见表2;实施例1中样品1-3见附图1。
表2:食品包装膜的性能测定结果
对比实施例1和2,由表1结果可知改性刺槐豆胶相比天然刺槐豆胶制备的食品包装膜的拉伸强度、断裂伸长率等机械性能提高了10~50%,膜的刚性和弹性都增加;对比实施例1中的5组样品,凝胶剂与成膜剂比值为1:5时,阻水系数可达0.0852g·mm·m-2·h-1·kPa-1,阻水效果好;保鲜效果测试表明,实施例1中的样品1-3储存的猪肉色泽变化最小,表明抗菌效果最好,可延长猪肉的储存时间,同时表明天然刺槐豆胶无抗菌性。另外,本发明的食品包装膜厚度为0.12±0.02mm,由附图1看出,膜气泡少,透明度高。
Claims (3)
2.一种食品包装膜的制备方法,其特征在于,包括如下步骤:
将0.2~0.5g助凝剂加入至90~150mL蒸馏水中磁力搅拌溶解,凝胶剂和成膜剂以1:3~1:7添加量比加入并搅拌分散均匀,逐渐加热升温至80~90℃,保温1.0h,使胶液充分溶胀,待用;将0.2~0.5g的增塑剂加入至10~50mL蒸馏水中,磁力搅拌加热并保持80~90℃,过滤,将滤液加入至待用胶液中磁力搅拌混合均匀,采用真空脱气装置对其进行高温脱气、除泡0.5h,降温至50~60℃,静置24h,让胶液进一步交联;将5g交联好的胶液倒置在50~60℃平板(10×12cm)模具上用另一块干净的平板模具进行压板,使胶液均匀平铺于模具上,置于25℃、30%RH恒温干燥箱中,干燥2~4h后,脱模,即可。
3.根据权利要求2所述的一种食品包装膜的制备方法,其特征在于,所述食品包装膜制备步骤中的凝胶剂与成膜剂添加量比为1:5。
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